| /* Integrated Register Allocator (IRA) entry point. |
| Copyright (C) 2006-2014 Free Software Foundation, Inc. |
| Contributed by Vladimir Makarov <vmakarov@redhat.com>. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* The integrated register allocator (IRA) is a |
| regional register allocator performing graph coloring on a top-down |
| traversal of nested regions. Graph coloring in a region is based |
| on Chaitin-Briggs algorithm. It is called integrated because |
| register coalescing, register live range splitting, and choosing a |
| better hard register are done on-the-fly during coloring. Register |
| coalescing and choosing a cheaper hard register is done by hard |
| register preferencing during hard register assigning. The live |
| range splitting is a byproduct of the regional register allocation. |
| |
| Major IRA notions are: |
| |
| o *Region* is a part of CFG where graph coloring based on |
| Chaitin-Briggs algorithm is done. IRA can work on any set of |
| nested CFG regions forming a tree. Currently the regions are |
| the entire function for the root region and natural loops for |
| the other regions. Therefore data structure representing a |
| region is called loop_tree_node. |
| |
| o *Allocno class* is a register class used for allocation of |
| given allocno. It means that only hard register of given |
| register class can be assigned to given allocno. In reality, |
| even smaller subset of (*profitable*) hard registers can be |
| assigned. In rare cases, the subset can be even smaller |
| because our modification of Chaitin-Briggs algorithm requires |
| that sets of hard registers can be assigned to allocnos forms a |
| forest, i.e. the sets can be ordered in a way where any |
| previous set is not intersected with given set or is a superset |
| of given set. |
| |
| o *Pressure class* is a register class belonging to a set of |
| register classes containing all of the hard-registers available |
| for register allocation. The set of all pressure classes for a |
| target is defined in the corresponding machine-description file |
| according some criteria. Register pressure is calculated only |
| for pressure classes and it affects some IRA decisions as |
| forming allocation regions. |
| |
| o *Allocno* represents the live range of a pseudo-register in a |
| region. Besides the obvious attributes like the corresponding |
| pseudo-register number, allocno class, conflicting allocnos and |
| conflicting hard-registers, there are a few allocno attributes |
| which are important for understanding the allocation algorithm: |
| |
| - *Live ranges*. This is a list of ranges of *program points* |
| where the allocno lives. Program points represent places |
| where a pseudo can be born or become dead (there are |
| approximately two times more program points than the insns) |
| and they are represented by integers starting with 0. The |
| live ranges are used to find conflicts between allocnos. |
| They also play very important role for the transformation of |
| the IRA internal representation of several regions into a one |
| region representation. The later is used during the reload |
| pass work because each allocno represents all of the |
| corresponding pseudo-registers. |
| |
| - *Hard-register costs*. This is a vector of size equal to the |
| number of available hard-registers of the allocno class. The |
| cost of a callee-clobbered hard-register for an allocno is |
| increased by the cost of save/restore code around the calls |
| through the given allocno's life. If the allocno is a move |
| instruction operand and another operand is a hard-register of |
| the allocno class, the cost of the hard-register is decreased |
| by the move cost. |
| |
| When an allocno is assigned, the hard-register with minimal |
| full cost is used. Initially, a hard-register's full cost is |
| the corresponding value from the hard-register's cost vector. |
| If the allocno is connected by a *copy* (see below) to |
| another allocno which has just received a hard-register, the |
| cost of the hard-register is decreased. Before choosing a |
| hard-register for an allocno, the allocno's current costs of |
| the hard-registers are modified by the conflict hard-register |
| costs of all of the conflicting allocnos which are not |
| assigned yet. |
| |
| - *Conflict hard-register costs*. This is a vector of the same |
| size as the hard-register costs vector. To permit an |
| unassigned allocno to get a better hard-register, IRA uses |
| this vector to calculate the final full cost of the |
| available hard-registers. Conflict hard-register costs of an |
| unassigned allocno are also changed with a change of the |
| hard-register cost of the allocno when a copy involving the |
| allocno is processed as described above. This is done to |
| show other unassigned allocnos that a given allocno prefers |
| some hard-registers in order to remove the move instruction |
| corresponding to the copy. |
| |
| o *Cap*. If a pseudo-register does not live in a region but |
| lives in a nested region, IRA creates a special allocno called |
| a cap in the outer region. A region cap is also created for a |
| subregion cap. |
| |
| o *Copy*. Allocnos can be connected by copies. Copies are used |
| to modify hard-register costs for allocnos during coloring. |
| Such modifications reflects a preference to use the same |
| hard-register for the allocnos connected by copies. Usually |
| copies are created for move insns (in this case it results in |
| register coalescing). But IRA also creates copies for operands |
| of an insn which should be assigned to the same hard-register |
| due to constraints in the machine description (it usually |
| results in removing a move generated in reload to satisfy |
| the constraints) and copies referring to the allocno which is |
| the output operand of an instruction and the allocno which is |
| an input operand dying in the instruction (creation of such |
| copies results in less register shuffling). IRA *does not* |
| create copies between the same register allocnos from different |
| regions because we use another technique for propagating |
| hard-register preference on the borders of regions. |
| |
| Allocnos (including caps) for the upper region in the region tree |
| *accumulate* information important for coloring from allocnos with |
| the same pseudo-register from nested regions. This includes |
| hard-register and memory costs, conflicts with hard-registers, |
| allocno conflicts, allocno copies and more. *Thus, attributes for |
| allocnos in a region have the same values as if the region had no |
| subregions*. It means that attributes for allocnos in the |
| outermost region corresponding to the function have the same values |
| as though the allocation used only one region which is the entire |
| function. It also means that we can look at IRA work as if the |
| first IRA did allocation for all function then it improved the |
| allocation for loops then their subloops and so on. |
| |
| IRA major passes are: |
| |
| o Building IRA internal representation which consists of the |
| following subpasses: |
| |
| * First, IRA builds regions and creates allocnos (file |
| ira-build.c) and initializes most of their attributes. |
| |
| * Then IRA finds an allocno class for each allocno and |
| calculates its initial (non-accumulated) cost of memory and |
| each hard-register of its allocno class (file ira-cost.c). |
| |
| * IRA creates live ranges of each allocno, calulates register |
| pressure for each pressure class in each region, sets up |
| conflict hard registers for each allocno and info about calls |
| the allocno lives through (file ira-lives.c). |
| |
| * IRA removes low register pressure loops from the regions |
| mostly to speed IRA up (file ira-build.c). |
| |
| * IRA propagates accumulated allocno info from lower region |
| allocnos to corresponding upper region allocnos (file |
| ira-build.c). |
| |
| * IRA creates all caps (file ira-build.c). |
| |
| * Having live-ranges of allocnos and their classes, IRA creates |
| conflicting allocnos for each allocno. Conflicting allocnos |
| are stored as a bit vector or array of pointers to the |
| conflicting allocnos whatever is more profitable (file |
| ira-conflicts.c). At this point IRA creates allocno copies. |
| |
| o Coloring. Now IRA has all necessary info to start graph coloring |
| process. It is done in each region on top-down traverse of the |
| region tree (file ira-color.c). There are following subpasses: |
| |
| * Finding profitable hard registers of corresponding allocno |
| class for each allocno. For example, only callee-saved hard |
| registers are frequently profitable for allocnos living |
| through colors. If the profitable hard register set of |
| allocno does not form a tree based on subset relation, we use |
| some approximation to form the tree. This approximation is |
| used to figure out trivial colorability of allocnos. The |
| approximation is a pretty rare case. |
| |
| * Putting allocnos onto the coloring stack. IRA uses Briggs |
| optimistic coloring which is a major improvement over |
| Chaitin's coloring. Therefore IRA does not spill allocnos at |
| this point. There is some freedom in the order of putting |
| allocnos on the stack which can affect the final result of |
| the allocation. IRA uses some heuristics to improve the |
| order. The major one is to form *threads* from colorable |
| allocnos and push them on the stack by threads. Thread is a |
| set of non-conflicting colorable allocnos connected by |
| copies. The thread contains allocnos from the colorable |
| bucket or colorable allocnos already pushed onto the coloring |
| stack. Pushing thread allocnos one after another onto the |
| stack increases chances of removing copies when the allocnos |
| get the same hard reg. |
| |
| We also use a modification of Chaitin-Briggs algorithm which |
| works for intersected register classes of allocnos. To |
| figure out trivial colorability of allocnos, the mentioned |
| above tree of hard register sets is used. To get an idea how |
| the algorithm works in i386 example, let us consider an |
| allocno to which any general hard register can be assigned. |
| If the allocno conflicts with eight allocnos to which only |
| EAX register can be assigned, given allocno is still |
| trivially colorable because all conflicting allocnos might be |
| assigned only to EAX and all other general hard registers are |
| still free. |
| |
| To get an idea of the used trivial colorability criterion, it |
| is also useful to read article "Graph-Coloring Register |
| Allocation for Irregular Architectures" by Michael D. Smith |
| and Glen Holloway. Major difference between the article |
| approach and approach used in IRA is that Smith's approach |
| takes register classes only from machine description and IRA |
| calculate register classes from intermediate code too |
| (e.g. an explicit usage of hard registers in RTL code for |
| parameter passing can result in creation of additional |
| register classes which contain or exclude the hard |
| registers). That makes IRA approach useful for improving |
| coloring even for architectures with regular register files |
| and in fact some benchmarking shows the improvement for |
| regular class architectures is even bigger than for irregular |
| ones. Another difference is that Smith's approach chooses |
| intersection of classes of all insn operands in which a given |
| pseudo occurs. IRA can use bigger classes if it is still |
| more profitable than memory usage. |
| |
| * Popping the allocnos from the stack and assigning them hard |
| registers. If IRA can not assign a hard register to an |
| allocno and the allocno is coalesced, IRA undoes the |
| coalescing and puts the uncoalesced allocnos onto the stack in |
| the hope that some such allocnos will get a hard register |
| separately. If IRA fails to assign hard register or memory |
| is more profitable for it, IRA spills the allocno. IRA |
| assigns the allocno the hard-register with minimal full |
| allocation cost which reflects the cost of usage of the |
| hard-register for the allocno and cost of usage of the |
| hard-register for allocnos conflicting with given allocno. |
| |
| * Chaitin-Briggs coloring assigns as many pseudos as possible |
| to hard registers. After coloringh we try to improve |
| allocation with cost point of view. We improve the |
| allocation by spilling some allocnos and assigning the freed |
| hard registers to other allocnos if it decreases the overall |
| allocation cost. |
| |
| * After allono assigning in the region, IRA modifies the hard |
| register and memory costs for the corresponding allocnos in |
| the subregions to reflect the cost of possible loads, stores, |
| or moves on the border of the region and its subregions. |
| When default regional allocation algorithm is used |
| (-fira-algorithm=mixed), IRA just propagates the assignment |
| for allocnos if the register pressure in the region for the |
| corresponding pressure class is less than number of available |
| hard registers for given pressure class. |
| |
| o Spill/restore code moving. When IRA performs an allocation |
| by traversing regions in top-down order, it does not know what |
| happens below in the region tree. Therefore, sometimes IRA |
| misses opportunities to perform a better allocation. A simple |
| optimization tries to improve allocation in a region having |
| subregions and containing in another region. If the |
| corresponding allocnos in the subregion are spilled, it spills |
| the region allocno if it is profitable. The optimization |
| implements a simple iterative algorithm performing profitable |
| transformations while they are still possible. It is fast in |
| practice, so there is no real need for a better time complexity |
| algorithm. |
| |
| o Code change. After coloring, two allocnos representing the |
| same pseudo-register outside and inside a region respectively |
| may be assigned to different locations (hard-registers or |
| memory). In this case IRA creates and uses a new |
| pseudo-register inside the region and adds code to move allocno |
| values on the region's borders. This is done during top-down |
| traversal of the regions (file ira-emit.c). In some |
| complicated cases IRA can create a new allocno to move allocno |
| values (e.g. when a swap of values stored in two hard-registers |
| is needed). At this stage, the new allocno is marked as |
| spilled. IRA still creates the pseudo-register and the moves |
| on the region borders even when both allocnos were assigned to |
| the same hard-register. If the reload pass spills a |
| pseudo-register for some reason, the effect will be smaller |
| because another allocno will still be in the hard-register. In |
| most cases, this is better then spilling both allocnos. If |
| reload does not change the allocation for the two |
| pseudo-registers, the trivial move will be removed by |
| post-reload optimizations. IRA does not generate moves for |
| allocnos assigned to the same hard register when the default |
| regional allocation algorithm is used and the register pressure |
| in the region for the corresponding pressure class is less than |
| number of available hard registers for given pressure class. |
| IRA also does some optimizations to remove redundant stores and |
| to reduce code duplication on the region borders. |
| |
| o Flattening internal representation. After changing code, IRA |
| transforms its internal representation for several regions into |
| one region representation (file ira-build.c). This process is |
| called IR flattening. Such process is more complicated than IR |
| rebuilding would be, but is much faster. |
| |
| o After IR flattening, IRA tries to assign hard registers to all |
| spilled allocnos. This is impelemented by a simple and fast |
| priority coloring algorithm (see function |
| ira_reassign_conflict_allocnos::ira-color.c). Here new allocnos |
| created during the code change pass can be assigned to hard |
| registers. |
| |
| o At the end IRA calls the reload pass. The reload pass |
| communicates with IRA through several functions in file |
| ira-color.c to improve its decisions in |
| |
| * sharing stack slots for the spilled pseudos based on IRA info |
| about pseudo-register conflicts. |
| |
| * reassigning hard-registers to all spilled pseudos at the end |
| of each reload iteration. |
| |
| * choosing a better hard-register to spill based on IRA info |
| about pseudo-register live ranges and the register pressure |
| in places where the pseudo-register lives. |
| |
| IRA uses a lot of data representing the target processors. These |
| data are initilized in file ira.c. |
| |
| If function has no loops (or the loops are ignored when |
| -fira-algorithm=CB is used), we have classic Chaitin-Briggs |
| coloring (only instead of separate pass of coalescing, we use hard |
| register preferencing). In such case, IRA works much faster |
| because many things are not made (like IR flattening, the |
| spill/restore optimization, and the code change). |
| |
| Literature is worth to read for better understanding the code: |
| |
| o Preston Briggs, Keith D. Cooper, Linda Torczon. Improvements to |
| Graph Coloring Register Allocation. |
| |
| o David Callahan, Brian Koblenz. Register allocation via |
| hierarchical graph coloring. |
| |
| o Keith Cooper, Anshuman Dasgupta, Jason Eckhardt. Revisiting Graph |
| Coloring Register Allocation: A Study of the Chaitin-Briggs and |
| Callahan-Koblenz Algorithms. |
| |
| o Guei-Yuan Lueh, Thomas Gross, and Ali-Reza Adl-Tabatabai. Global |
| Register Allocation Based on Graph Fusion. |
| |
| o Michael D. Smith and Glenn Holloway. Graph-Coloring Register |
| Allocation for Irregular Architectures |
| |
| o Vladimir Makarov. The Integrated Register Allocator for GCC. |
| |
| o Vladimir Makarov. The top-down register allocator for irregular |
| register file architectures. |
| |
| */ |
| |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "tm.h" |
| #include "regs.h" |
| #include "tree.h" |
| #include "rtl.h" |
| #include "tm_p.h" |
| #include "target.h" |
| #include "flags.h" |
| #include "obstack.h" |
| #include "bitmap.h" |
| #include "hard-reg-set.h" |
| #include "basic-block.h" |
| #include "df.h" |
| #include "expr.h" |
| #include "recog.h" |
| #include "params.h" |
| #include "tree-pass.h" |
| #include "output.h" |
| #include "except.h" |
| #include "reload.h" |
| #include "diagnostic-core.h" |
| #include "function.h" |
| #include "ggc.h" |
| #include "ira-int.h" |
| #include "lra.h" |
| #include "dce.h" |
| #include "dbgcnt.h" |
| |
| struct target_ira default_target_ira; |
| struct target_ira_int default_target_ira_int; |
| #if SWITCHABLE_TARGET |
| struct target_ira *this_target_ira = &default_target_ira; |
| struct target_ira_int *this_target_ira_int = &default_target_ira_int; |
| #endif |
| |
| /* A modified value of flag `-fira-verbose' used internally. */ |
| int internal_flag_ira_verbose; |
| |
| /* Dump file of the allocator if it is not NULL. */ |
| FILE *ira_dump_file; |
| |
| /* The number of elements in the following array. */ |
| int ira_spilled_reg_stack_slots_num; |
| |
| /* The following array contains info about spilled pseudo-registers |
| stack slots used in current function so far. */ |
| struct ira_spilled_reg_stack_slot *ira_spilled_reg_stack_slots; |
| |
| /* Correspondingly overall cost of the allocation, overall cost before |
| reload, cost of the allocnos assigned to hard-registers, cost of |
| the allocnos assigned to memory, cost of loads, stores and register |
| move insns generated for pseudo-register live range splitting (see |
| ira-emit.c). */ |
| int ira_overall_cost, overall_cost_before; |
| int ira_reg_cost, ira_mem_cost; |
| int ira_load_cost, ira_store_cost, ira_shuffle_cost; |
| int ira_move_loops_num, ira_additional_jumps_num; |
| |
| /* All registers that can be eliminated. */ |
| |
| HARD_REG_SET eliminable_regset; |
| |
| /* Value of max_reg_num () before IRA work start. This value helps |
| us to recognize a situation when new pseudos were created during |
| IRA work. */ |
| static int max_regno_before_ira; |
| |
| /* Temporary hard reg set used for a different calculation. */ |
| static HARD_REG_SET temp_hard_regset; |
| |
| #define last_mode_for_init_move_cost \ |
| (this_target_ira_int->x_last_mode_for_init_move_cost) |
| |
| |
| /* The function sets up the map IRA_REG_MODE_HARD_REGSET. */ |
| static void |
| setup_reg_mode_hard_regset (void) |
| { |
| int i, m, hard_regno; |
| |
| for (m = 0; m < NUM_MACHINE_MODES; m++) |
| for (hard_regno = 0; hard_regno < FIRST_PSEUDO_REGISTER; hard_regno++) |
| { |
| CLEAR_HARD_REG_SET (ira_reg_mode_hard_regset[hard_regno][m]); |
| for (i = hard_regno_nregs[hard_regno][m] - 1; i >= 0; i--) |
| if (hard_regno + i < FIRST_PSEUDO_REGISTER) |
| SET_HARD_REG_BIT (ira_reg_mode_hard_regset[hard_regno][m], |
| hard_regno + i); |
| } |
| } |
| |
| |
| #define no_unit_alloc_regs \ |
| (this_target_ira_int->x_no_unit_alloc_regs) |
| |
| /* The function sets up the three arrays declared above. */ |
| static void |
| setup_class_hard_regs (void) |
| { |
| int cl, i, hard_regno, n; |
| HARD_REG_SET processed_hard_reg_set; |
| |
| ira_assert (SHRT_MAX >= FIRST_PSEUDO_REGISTER); |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| CLEAR_HARD_REG_SET (processed_hard_reg_set); |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| { |
| ira_non_ordered_class_hard_regs[cl][i] = -1; |
| ira_class_hard_reg_index[cl][i] = -1; |
| } |
| for (n = 0, i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| { |
| #ifdef REG_ALLOC_ORDER |
| hard_regno = reg_alloc_order[i]; |
| #else |
| hard_regno = i; |
| #endif |
| if (TEST_HARD_REG_BIT (processed_hard_reg_set, hard_regno)) |
| continue; |
| SET_HARD_REG_BIT (processed_hard_reg_set, hard_regno); |
| if (! TEST_HARD_REG_BIT (temp_hard_regset, hard_regno)) |
| ira_class_hard_reg_index[cl][hard_regno] = -1; |
| else |
| { |
| ira_class_hard_reg_index[cl][hard_regno] = n; |
| ira_class_hard_regs[cl][n++] = hard_regno; |
| } |
| } |
| ira_class_hard_regs_num[cl] = n; |
| for (n = 0, i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| if (TEST_HARD_REG_BIT (temp_hard_regset, i)) |
| ira_non_ordered_class_hard_regs[cl][n++] = i; |
| ira_assert (ira_class_hard_regs_num[cl] == n); |
| } |
| } |
| |
| /* Set up global variables defining info about hard registers for the |
| allocation. These depend on USE_HARD_FRAME_P whose TRUE value means |
| that we can use the hard frame pointer for the allocation. */ |
| static void |
| setup_alloc_regs (bool use_hard_frame_p) |
| { |
| #ifdef ADJUST_REG_ALLOC_ORDER |
| ADJUST_REG_ALLOC_ORDER; |
| #endif |
| COPY_HARD_REG_SET (no_unit_alloc_regs, fixed_reg_set); |
| if (! use_hard_frame_p) |
| SET_HARD_REG_BIT (no_unit_alloc_regs, HARD_FRAME_POINTER_REGNUM); |
| setup_class_hard_regs (); |
| } |
| |
| |
| |
| #define alloc_reg_class_subclasses \ |
| (this_target_ira_int->x_alloc_reg_class_subclasses) |
| |
| /* Initialize the table of subclasses of each reg class. */ |
| static void |
| setup_reg_subclasses (void) |
| { |
| int i, j; |
| HARD_REG_SET temp_hard_regset2; |
| |
| for (i = 0; i < N_REG_CLASSES; i++) |
| for (j = 0; j < N_REG_CLASSES; j++) |
| alloc_reg_class_subclasses[i][j] = LIM_REG_CLASSES; |
| |
| for (i = 0; i < N_REG_CLASSES; i++) |
| { |
| if (i == (int) NO_REGS) |
| continue; |
| |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[i]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| if (hard_reg_set_empty_p (temp_hard_regset)) |
| continue; |
| for (j = 0; j < N_REG_CLASSES; j++) |
| if (i != j) |
| { |
| enum reg_class *p; |
| |
| COPY_HARD_REG_SET (temp_hard_regset2, reg_class_contents[j]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, no_unit_alloc_regs); |
| if (! hard_reg_set_subset_p (temp_hard_regset, |
| temp_hard_regset2)) |
| continue; |
| p = &alloc_reg_class_subclasses[j][0]; |
| while (*p != LIM_REG_CLASSES) p++; |
| *p = (enum reg_class) i; |
| } |
| } |
| } |
| |
| |
| |
| /* Set up IRA_MEMORY_MOVE_COST and IRA_MAX_MEMORY_MOVE_COST. */ |
| static void |
| setup_class_subset_and_memory_move_costs (void) |
| { |
| int cl, cl2, mode, cost; |
| HARD_REG_SET temp_hard_regset2; |
| |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| ira_memory_move_cost[mode][NO_REGS][0] |
| = ira_memory_move_cost[mode][NO_REGS][1] = SHRT_MAX; |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| { |
| if (cl != (int) NO_REGS) |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| { |
| ira_max_memory_move_cost[mode][cl][0] |
| = ira_memory_move_cost[mode][cl][0] |
| = memory_move_cost ((enum machine_mode) mode, |
| (reg_class_t) cl, false); |
| ira_max_memory_move_cost[mode][cl][1] |
| = ira_memory_move_cost[mode][cl][1] |
| = memory_move_cost ((enum machine_mode) mode, |
| (reg_class_t) cl, true); |
| /* Costs for NO_REGS are used in cost calculation on the |
| 1st pass when the preferred register classes are not |
| known yet. In this case we take the best scenario. */ |
| if (ira_memory_move_cost[mode][NO_REGS][0] |
| > ira_memory_move_cost[mode][cl][0]) |
| ira_max_memory_move_cost[mode][NO_REGS][0] |
| = ira_memory_move_cost[mode][NO_REGS][0] |
| = ira_memory_move_cost[mode][cl][0]; |
| if (ira_memory_move_cost[mode][NO_REGS][1] |
| > ira_memory_move_cost[mode][cl][1]) |
| ira_max_memory_move_cost[mode][NO_REGS][1] |
| = ira_memory_move_cost[mode][NO_REGS][1] |
| = ira_memory_move_cost[mode][cl][1]; |
| } |
| } |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| for (cl2 = (int) N_REG_CLASSES - 1; cl2 >= 0; cl2--) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| COPY_HARD_REG_SET (temp_hard_regset2, reg_class_contents[cl2]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, no_unit_alloc_regs); |
| ira_class_subset_p[cl][cl2] |
| = hard_reg_set_subset_p (temp_hard_regset, temp_hard_regset2); |
| if (! hard_reg_set_empty_p (temp_hard_regset2) |
| && hard_reg_set_subset_p (reg_class_contents[cl2], |
| reg_class_contents[cl])) |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| { |
| cost = ira_memory_move_cost[mode][cl2][0]; |
| if (cost > ira_max_memory_move_cost[mode][cl][0]) |
| ira_max_memory_move_cost[mode][cl][0] = cost; |
| cost = ira_memory_move_cost[mode][cl2][1]; |
| if (cost > ira_max_memory_move_cost[mode][cl][1]) |
| ira_max_memory_move_cost[mode][cl][1] = cost; |
| } |
| } |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| { |
| ira_memory_move_cost[mode][cl][0] |
| = ira_max_memory_move_cost[mode][cl][0]; |
| ira_memory_move_cost[mode][cl][1] |
| = ira_max_memory_move_cost[mode][cl][1]; |
| } |
| setup_reg_subclasses (); |
| } |
| |
| |
| |
| /* Define the following macro if allocation through malloc if |
| preferable. */ |
| #define IRA_NO_OBSTACK |
| |
| #ifndef IRA_NO_OBSTACK |
| /* Obstack used for storing all dynamic data (except bitmaps) of the |
| IRA. */ |
| static struct obstack ira_obstack; |
| #endif |
| |
| /* Obstack used for storing all bitmaps of the IRA. */ |
| static struct bitmap_obstack ira_bitmap_obstack; |
| |
| /* Allocate memory of size LEN for IRA data. */ |
| void * |
| ira_allocate (size_t len) |
| { |
| void *res; |
| |
| #ifndef IRA_NO_OBSTACK |
| res = obstack_alloc (&ira_obstack, len); |
| #else |
| res = xmalloc (len); |
| #endif |
| return res; |
| } |
| |
| /* Free memory ADDR allocated for IRA data. */ |
| void |
| ira_free (void *addr ATTRIBUTE_UNUSED) |
| { |
| #ifndef IRA_NO_OBSTACK |
| /* do nothing */ |
| #else |
| free (addr); |
| #endif |
| } |
| |
| |
| /* Allocate and returns bitmap for IRA. */ |
| bitmap |
| ira_allocate_bitmap (void) |
| { |
| return BITMAP_ALLOC (&ira_bitmap_obstack); |
| } |
| |
| /* Free bitmap B allocated for IRA. */ |
| void |
| ira_free_bitmap (bitmap b ATTRIBUTE_UNUSED) |
| { |
| /* do nothing */ |
| } |
| |
| |
| |
| /* Output information about allocation of all allocnos (except for |
| caps) into file F. */ |
| void |
| ira_print_disposition (FILE *f) |
| { |
| int i, n, max_regno; |
| ira_allocno_t a; |
| basic_block bb; |
| |
| fprintf (f, "Disposition:"); |
| max_regno = max_reg_num (); |
| for (n = 0, i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) |
| for (a = ira_regno_allocno_map[i]; |
| a != NULL; |
| a = ALLOCNO_NEXT_REGNO_ALLOCNO (a)) |
| { |
| if (n % 4 == 0) |
| fprintf (f, "\n"); |
| n++; |
| fprintf (f, " %4d:r%-4d", ALLOCNO_NUM (a), ALLOCNO_REGNO (a)); |
| if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL) |
| fprintf (f, "b%-3d", bb->index); |
| else |
| fprintf (f, "l%-3d", ALLOCNO_LOOP_TREE_NODE (a)->loop_num); |
| if (ALLOCNO_HARD_REGNO (a) >= 0) |
| fprintf (f, " %3d", ALLOCNO_HARD_REGNO (a)); |
| else |
| fprintf (f, " mem"); |
| } |
| fprintf (f, "\n"); |
| } |
| |
| /* Outputs information about allocation of all allocnos into |
| stderr. */ |
| void |
| ira_debug_disposition (void) |
| { |
| ira_print_disposition (stderr); |
| } |
| |
| |
| |
| /* Set up ira_stack_reg_pressure_class which is the biggest pressure |
| register class containing stack registers or NO_REGS if there are |
| no stack registers. To find this class, we iterate through all |
| register pressure classes and choose the first register pressure |
| class containing all the stack registers and having the biggest |
| size. */ |
| static void |
| setup_stack_reg_pressure_class (void) |
| { |
| ira_stack_reg_pressure_class = NO_REGS; |
| #ifdef STACK_REGS |
| { |
| int i, best, size; |
| enum reg_class cl; |
| HARD_REG_SET temp_hard_regset2; |
| |
| CLEAR_HARD_REG_SET (temp_hard_regset); |
| for (i = FIRST_STACK_REG; i <= LAST_STACK_REG; i++) |
| SET_HARD_REG_BIT (temp_hard_regset, i); |
| best = 0; |
| for (i = 0; i < ira_pressure_classes_num; i++) |
| { |
| cl = ira_pressure_classes[i]; |
| COPY_HARD_REG_SET (temp_hard_regset2, temp_hard_regset); |
| AND_HARD_REG_SET (temp_hard_regset2, reg_class_contents[cl]); |
| size = hard_reg_set_size (temp_hard_regset2); |
| if (best < size) |
| { |
| best = size; |
| ira_stack_reg_pressure_class = cl; |
| } |
| } |
| } |
| #endif |
| } |
| |
| /* Find pressure classes which are register classes for which we |
| calculate register pressure in IRA, register pressure sensitive |
| insn scheduling, and register pressure sensitive loop invariant |
| motion. |
| |
| To make register pressure calculation easy, we always use |
| non-intersected register pressure classes. A move of hard |
| registers from one register pressure class is not more expensive |
| than load and store of the hard registers. Most likely an allocno |
| class will be a subset of a register pressure class and in many |
| cases a register pressure class. That makes usage of register |
| pressure classes a good approximation to find a high register |
| pressure. */ |
| static void |
| setup_pressure_classes (void) |
| { |
| int cost, i, n, curr; |
| int cl, cl2; |
| enum reg_class pressure_classes[N_REG_CLASSES]; |
| int m; |
| HARD_REG_SET temp_hard_regset2; |
| bool insert_p; |
| |
| n = 0; |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| { |
| if (ira_class_hard_regs_num[cl] == 0) |
| continue; |
| if (ira_class_hard_regs_num[cl] != 1 |
| /* A register class without subclasses may contain a few |
| hard registers and movement between them is costly |
| (e.g. SPARC FPCC registers). We still should consider it |
| as a candidate for a pressure class. */ |
| && alloc_reg_class_subclasses[cl][0] < cl) |
| { |
| /* Check that the moves between any hard registers of the |
| current class are not more expensive for a legal mode |
| than load/store of the hard registers of the current |
| class. Such class is a potential candidate to be a |
| register pressure class. */ |
| for (m = 0; m < NUM_MACHINE_MODES; m++) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, |
| ira_prohibited_class_mode_regs[cl][m]); |
| if (hard_reg_set_empty_p (temp_hard_regset)) |
| continue; |
| ira_init_register_move_cost_if_necessary ((enum machine_mode) m); |
| cost = ira_register_move_cost[m][cl][cl]; |
| if (cost <= ira_max_memory_move_cost[m][cl][1] |
| || cost <= ira_max_memory_move_cost[m][cl][0]) |
| break; |
| } |
| if (m >= NUM_MACHINE_MODES) |
| continue; |
| } |
| curr = 0; |
| insert_p = true; |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| /* Remove so far added pressure classes which are subset of the |
| current candidate class. Prefer GENERAL_REGS as a pressure |
| register class to another class containing the same |
| allocatable hard registers. We do this because machine |
| dependent cost hooks might give wrong costs for the latter |
| class but always give the right cost for the former class |
| (GENERAL_REGS). */ |
| for (i = 0; i < n; i++) |
| { |
| cl2 = pressure_classes[i]; |
| COPY_HARD_REG_SET (temp_hard_regset2, reg_class_contents[cl2]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, no_unit_alloc_regs); |
| if (hard_reg_set_subset_p (temp_hard_regset, temp_hard_regset2) |
| && (! hard_reg_set_equal_p (temp_hard_regset, temp_hard_regset2) |
| || cl2 == (int) GENERAL_REGS)) |
| { |
| pressure_classes[curr++] = (enum reg_class) cl2; |
| insert_p = false; |
| continue; |
| } |
| if (hard_reg_set_subset_p (temp_hard_regset2, temp_hard_regset) |
| && (! hard_reg_set_equal_p (temp_hard_regset2, temp_hard_regset) |
| || cl == (int) GENERAL_REGS)) |
| continue; |
| if (hard_reg_set_equal_p (temp_hard_regset2, temp_hard_regset)) |
| insert_p = false; |
| pressure_classes[curr++] = (enum reg_class) cl2; |
| } |
| /* If the current candidate is a subset of a so far added |
| pressure class, don't add it to the list of the pressure |
| classes. */ |
| if (insert_p) |
| pressure_classes[curr++] = (enum reg_class) cl; |
| n = curr; |
| } |
| #ifdef ENABLE_IRA_CHECKING |
| { |
| HARD_REG_SET ignore_hard_regs; |
| |
| /* Check pressure classes correctness: here we check that hard |
| registers from all register pressure classes contains all hard |
| registers available for the allocation. */ |
| CLEAR_HARD_REG_SET (temp_hard_regset); |
| CLEAR_HARD_REG_SET (temp_hard_regset2); |
| COPY_HARD_REG_SET (ignore_hard_regs, no_unit_alloc_regs); |
| for (cl = 0; cl < LIM_REG_CLASSES; cl++) |
| { |
| /* For some targets (like MIPS with MD_REGS), there are some |
| classes with hard registers available for allocation but |
| not able to hold value of any mode. */ |
| for (m = 0; m < NUM_MACHINE_MODES; m++) |
| if (contains_reg_of_mode[cl][m]) |
| break; |
| if (m >= NUM_MACHINE_MODES) |
| { |
| IOR_HARD_REG_SET (ignore_hard_regs, reg_class_contents[cl]); |
| continue; |
| } |
| for (i = 0; i < n; i++) |
| if ((int) pressure_classes[i] == cl) |
| break; |
| IOR_HARD_REG_SET (temp_hard_regset2, reg_class_contents[cl]); |
| if (i < n) |
| IOR_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| } |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| /* Some targets (like SPARC with ICC reg) have alocatable regs |
| for which no reg class is defined. */ |
| if (REGNO_REG_CLASS (i) == NO_REGS) |
| SET_HARD_REG_BIT (ignore_hard_regs, i); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, ignore_hard_regs); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, ignore_hard_regs); |
| ira_assert (hard_reg_set_subset_p (temp_hard_regset2, temp_hard_regset)); |
| } |
| #endif |
| ira_pressure_classes_num = 0; |
| for (i = 0; i < n; i++) |
| { |
| cl = (int) pressure_classes[i]; |
| ira_reg_pressure_class_p[cl] = true; |
| ira_pressure_classes[ira_pressure_classes_num++] = (enum reg_class) cl; |
| } |
| setup_stack_reg_pressure_class (); |
| } |
| |
| /* Set up IRA_UNIFORM_CLASS_P. Uniform class is a register class |
| whose register move cost between any registers of the class is the |
| same as for all its subclasses. We use the data to speed up the |
| 2nd pass of calculations of allocno costs. */ |
| static void |
| setup_uniform_class_p (void) |
| { |
| int i, cl, cl2, m; |
| |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| { |
| ira_uniform_class_p[cl] = false; |
| if (ira_class_hard_regs_num[cl] == 0) |
| continue; |
| /* We can not use alloc_reg_class_subclasses here because move |
| cost hooks does not take into account that some registers are |
| unavailable for the subtarget. E.g. for i686, INT_SSE_REGS |
| is element of alloc_reg_class_subclasses for GENERAL_REGS |
| because SSE regs are unavailable. */ |
| for (i = 0; (cl2 = reg_class_subclasses[cl][i]) != LIM_REG_CLASSES; i++) |
| { |
| if (ira_class_hard_regs_num[cl2] == 0) |
| continue; |
| for (m = 0; m < NUM_MACHINE_MODES; m++) |
| if (contains_reg_of_mode[cl][m] && contains_reg_of_mode[cl2][m]) |
| { |
| ira_init_register_move_cost_if_necessary ((enum machine_mode) m); |
| if (ira_register_move_cost[m][cl][cl] |
| != ira_register_move_cost[m][cl2][cl2]) |
| break; |
| } |
| if (m < NUM_MACHINE_MODES) |
| break; |
| } |
| if (cl2 == LIM_REG_CLASSES) |
| ira_uniform_class_p[cl] = true; |
| } |
| } |
| |
| /* Set up IRA_ALLOCNO_CLASSES, IRA_ALLOCNO_CLASSES_NUM, |
| IRA_IMPORTANT_CLASSES, and IRA_IMPORTANT_CLASSES_NUM. |
| |
| Target may have many subtargets and not all target hard regiters can |
| be used for allocation, e.g. x86 port in 32-bit mode can not use |
| hard registers introduced in x86-64 like r8-r15). Some classes |
| might have the same allocatable hard registers, e.g. INDEX_REGS |
| and GENERAL_REGS in x86 port in 32-bit mode. To decrease different |
| calculations efforts we introduce allocno classes which contain |
| unique non-empty sets of allocatable hard-registers. |
| |
| Pseudo class cost calculation in ira-costs.c is very expensive. |
| Therefore we are trying to decrease number of classes involved in |
| such calculation. Register classes used in the cost calculation |
| are called important classes. They are allocno classes and other |
| non-empty classes whose allocatable hard register sets are inside |
| of an allocno class hard register set. From the first sight, it |
| looks like that they are just allocno classes. It is not true. In |
| example of x86-port in 32-bit mode, allocno classes will contain |
| GENERAL_REGS but not LEGACY_REGS (because allocatable hard |
| registers are the same for the both classes). The important |
| classes will contain GENERAL_REGS and LEGACY_REGS. It is done |
| because a machine description insn constraint may refers for |
| LEGACY_REGS and code in ira-costs.c is mostly base on investigation |
| of the insn constraints. */ |
| static void |
| setup_allocno_and_important_classes (void) |
| { |
| int i, j, n, cl; |
| bool set_p; |
| HARD_REG_SET temp_hard_regset2; |
| static enum reg_class classes[LIM_REG_CLASSES + 1]; |
| |
| n = 0; |
| /* Collect classes which contain unique sets of allocatable hard |
| registers. Prefer GENERAL_REGS to other classes containing the |
| same set of hard registers. */ |
| for (i = 0; i < LIM_REG_CLASSES; i++) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[i]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| for (j = 0; j < n; j++) |
| { |
| cl = classes[j]; |
| COPY_HARD_REG_SET (temp_hard_regset2, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, |
| no_unit_alloc_regs); |
| if (hard_reg_set_equal_p (temp_hard_regset, |
| temp_hard_regset2)) |
| break; |
| } |
| if (j >= n) |
| classes[n++] = (enum reg_class) i; |
| else if (i == GENERAL_REGS) |
| /* Prefer general regs. For i386 example, it means that |
| we prefer GENERAL_REGS over INDEX_REGS or LEGACY_REGS |
| (all of them consists of the same available hard |
| registers). */ |
| classes[j] = (enum reg_class) i; |
| } |
| classes[n] = LIM_REG_CLASSES; |
| |
| /* Set up classes which can be used for allocnos as classes |
| conatining non-empty unique sets of allocatable hard |
| registers. */ |
| ira_allocno_classes_num = 0; |
| for (i = 0; (cl = classes[i]) != LIM_REG_CLASSES; i++) |
| if (ira_class_hard_regs_num[cl] > 0) |
| ira_allocno_classes[ira_allocno_classes_num++] = (enum reg_class) cl; |
| ira_important_classes_num = 0; |
| /* Add non-allocno classes containing to non-empty set of |
| allocatable hard regs. */ |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| if (ira_class_hard_regs_num[cl] > 0) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| set_p = false; |
| for (j = 0; j < ira_allocno_classes_num; j++) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset2, |
| reg_class_contents[ira_allocno_classes[j]]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset2, no_unit_alloc_regs); |
| if ((enum reg_class) cl == ira_allocno_classes[j]) |
| break; |
| else if (hard_reg_set_subset_p (temp_hard_regset, |
| temp_hard_regset2)) |
| set_p = true; |
| } |
| if (set_p && j >= ira_allocno_classes_num) |
| ira_important_classes[ira_important_classes_num++] |
| = (enum reg_class) cl; |
| } |
| /* Now add allocno classes to the important classes. */ |
| for (j = 0; j < ira_allocno_classes_num; j++) |
| ira_important_classes[ira_important_classes_num++] |
| = ira_allocno_classes[j]; |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| { |
| ira_reg_allocno_class_p[cl] = false; |
| ira_reg_pressure_class_p[cl] = false; |
| } |
| for (j = 0; j < ira_allocno_classes_num; j++) |
| ira_reg_allocno_class_p[ira_allocno_classes[j]] = true; |
| setup_pressure_classes (); |
| setup_uniform_class_p (); |
| } |
| |
| /* Setup translation in CLASS_TRANSLATE of all classes into a class |
| given by array CLASSES of length CLASSES_NUM. The function is used |
| make translation any reg class to an allocno class or to an |
| pressure class. This translation is necessary for some |
| calculations when we can use only allocno or pressure classes and |
| such translation represents an approximate representation of all |
| classes. |
| |
| The translation in case when allocatable hard register set of a |
| given class is subset of allocatable hard register set of a class |
| in CLASSES is pretty simple. We use smallest classes from CLASSES |
| containing a given class. If allocatable hard register set of a |
| given class is not a subset of any corresponding set of a class |
| from CLASSES, we use the cheapest (with load/store point of view) |
| class from CLASSES whose set intersects with given class set */ |
| static void |
| setup_class_translate_array (enum reg_class *class_translate, |
| int classes_num, enum reg_class *classes) |
| { |
| int cl, mode; |
| enum reg_class aclass, best_class, *cl_ptr; |
| int i, cost, min_cost, best_cost; |
| |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| class_translate[cl] = NO_REGS; |
| |
| for (i = 0; i < classes_num; i++) |
| { |
| aclass = classes[i]; |
| for (cl_ptr = &alloc_reg_class_subclasses[aclass][0]; |
| (cl = *cl_ptr) != LIM_REG_CLASSES; |
| cl_ptr++) |
| if (class_translate[cl] == NO_REGS) |
| class_translate[cl] = aclass; |
| class_translate[aclass] = aclass; |
| } |
| /* For classes which are not fully covered by one of given classes |
| (in other words covered by more one given class), use the |
| cheapest class. */ |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| { |
| if (cl == NO_REGS || class_translate[cl] != NO_REGS) |
| continue; |
| best_class = NO_REGS; |
| best_cost = INT_MAX; |
| for (i = 0; i < classes_num; i++) |
| { |
| aclass = classes[i]; |
| COPY_HARD_REG_SET (temp_hard_regset, |
| reg_class_contents[aclass]); |
| AND_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| if (! hard_reg_set_empty_p (temp_hard_regset)) |
| { |
| min_cost = INT_MAX; |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| { |
| cost = (ira_memory_move_cost[mode][aclass][0] |
| + ira_memory_move_cost[mode][aclass][1]); |
| if (min_cost > cost) |
| min_cost = cost; |
| } |
| if (best_class == NO_REGS || best_cost > min_cost) |
| { |
| best_class = aclass; |
| best_cost = min_cost; |
| } |
| } |
| } |
| class_translate[cl] = best_class; |
| } |
| } |
| |
| /* Set up array IRA_ALLOCNO_CLASS_TRANSLATE and |
| IRA_PRESSURE_CLASS_TRANSLATE. */ |
| static void |
| setup_class_translate (void) |
| { |
| setup_class_translate_array (ira_allocno_class_translate, |
| ira_allocno_classes_num, ira_allocno_classes); |
| setup_class_translate_array (ira_pressure_class_translate, |
| ira_pressure_classes_num, ira_pressure_classes); |
| } |
| |
| /* Order numbers of allocno classes in original target allocno class |
| array, -1 for non-allocno classes. */ |
| static int allocno_class_order[N_REG_CLASSES]; |
| |
| /* The function used to sort the important classes. */ |
| static int |
| comp_reg_classes_func (const void *v1p, const void *v2p) |
| { |
| enum reg_class cl1 = *(const enum reg_class *) v1p; |
| enum reg_class cl2 = *(const enum reg_class *) v2p; |
| enum reg_class tcl1, tcl2; |
| int diff; |
| |
| tcl1 = ira_allocno_class_translate[cl1]; |
| tcl2 = ira_allocno_class_translate[cl2]; |
| if (tcl1 != NO_REGS && tcl2 != NO_REGS |
| && (diff = allocno_class_order[tcl1] - allocno_class_order[tcl2]) != 0) |
| return diff; |
| return (int) cl1 - (int) cl2; |
| } |
| |
| /* For correct work of function setup_reg_class_relation we need to |
| reorder important classes according to the order of their allocno |
| classes. It places important classes containing the same |
| allocatable hard register set adjacent to each other and allocno |
| class with the allocatable hard register set right after the other |
| important classes with the same set. |
| |
| In example from comments of function |
| setup_allocno_and_important_classes, it places LEGACY_REGS and |
| GENERAL_REGS close to each other and GENERAL_REGS is after |
| LEGACY_REGS. */ |
| static void |
| reorder_important_classes (void) |
| { |
| int i; |
| |
| for (i = 0; i < N_REG_CLASSES; i++) |
| allocno_class_order[i] = -1; |
| for (i = 0; i < ira_allocno_classes_num; i++) |
| allocno_class_order[ira_allocno_classes[i]] = i; |
| qsort (ira_important_classes, ira_important_classes_num, |
| sizeof (enum reg_class), comp_reg_classes_func); |
| for (i = 0; i < ira_important_classes_num; i++) |
| ira_important_class_nums[ira_important_classes[i]] = i; |
| } |
| |
| /* Set up IRA_REG_CLASS_SUBUNION, IRA_REG_CLASS_SUPERUNION, |
| IRA_REG_CLASS_SUPER_CLASSES, IRA_REG_CLASSES_INTERSECT, and |
| IRA_REG_CLASSES_INTERSECT_P. For the meaning of the relations, |
| please see corresponding comments in ira-int.h. */ |
| static void |
| setup_reg_class_relations (void) |
| { |
| int i, cl1, cl2, cl3; |
| HARD_REG_SET intersection_set, union_set, temp_set2; |
| bool important_class_p[N_REG_CLASSES]; |
| |
| memset (important_class_p, 0, sizeof (important_class_p)); |
| for (i = 0; i < ira_important_classes_num; i++) |
| important_class_p[ira_important_classes[i]] = true; |
| for (cl1 = 0; cl1 < N_REG_CLASSES; cl1++) |
| { |
| ira_reg_class_super_classes[cl1][0] = LIM_REG_CLASSES; |
| for (cl2 = 0; cl2 < N_REG_CLASSES; cl2++) |
| { |
| ira_reg_classes_intersect_p[cl1][cl2] = false; |
| ira_reg_class_intersect[cl1][cl2] = NO_REGS; |
| ira_reg_class_subset[cl1][cl2] = NO_REGS; |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl1]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| COPY_HARD_REG_SET (temp_set2, reg_class_contents[cl2]); |
| AND_COMPL_HARD_REG_SET (temp_set2, no_unit_alloc_regs); |
| if (hard_reg_set_empty_p (temp_hard_regset) |
| && hard_reg_set_empty_p (temp_set2)) |
| { |
| /* The both classes have no allocatable hard registers |
| -- take all class hard registers into account and use |
| reg_class_subunion and reg_class_superunion. */ |
| for (i = 0;; i++) |
| { |
| cl3 = reg_class_subclasses[cl1][i]; |
| if (cl3 == LIM_REG_CLASSES) |
| break; |
| if (reg_class_subset_p (ira_reg_class_intersect[cl1][cl2], |
| (enum reg_class) cl3)) |
| ira_reg_class_intersect[cl1][cl2] = (enum reg_class) cl3; |
| } |
| ira_reg_class_subunion[cl1][cl2] = reg_class_subunion[cl1][cl2]; |
| ira_reg_class_superunion[cl1][cl2] = reg_class_superunion[cl1][cl2]; |
| continue; |
| } |
| ira_reg_classes_intersect_p[cl1][cl2] |
| = hard_reg_set_intersect_p (temp_hard_regset, temp_set2); |
| if (important_class_p[cl1] && important_class_p[cl2] |
| && hard_reg_set_subset_p (temp_hard_regset, temp_set2)) |
| { |
| /* CL1 and CL2 are important classes and CL1 allocatable |
| hard register set is inside of CL2 allocatable hard |
| registers -- make CL1 a superset of CL2. */ |
| enum reg_class *p; |
| |
| p = &ira_reg_class_super_classes[cl1][0]; |
| while (*p != LIM_REG_CLASSES) |
| p++; |
| *p++ = (enum reg_class) cl2; |
| *p = LIM_REG_CLASSES; |
| } |
| ira_reg_class_subunion[cl1][cl2] = NO_REGS; |
| ira_reg_class_superunion[cl1][cl2] = NO_REGS; |
| COPY_HARD_REG_SET (intersection_set, reg_class_contents[cl1]); |
| AND_HARD_REG_SET (intersection_set, reg_class_contents[cl2]); |
| AND_COMPL_HARD_REG_SET (intersection_set, no_unit_alloc_regs); |
| COPY_HARD_REG_SET (union_set, reg_class_contents[cl1]); |
| IOR_HARD_REG_SET (union_set, reg_class_contents[cl2]); |
| AND_COMPL_HARD_REG_SET (union_set, no_unit_alloc_regs); |
| for (cl3 = 0; cl3 < N_REG_CLASSES; cl3++) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl3]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| if (hard_reg_set_subset_p (temp_hard_regset, intersection_set)) |
| { |
| /* CL3 allocatable hard register set is inside of |
| intersection of allocatable hard register sets |
| of CL1 and CL2. */ |
| if (important_class_p[cl3]) |
| { |
| COPY_HARD_REG_SET |
| (temp_set2, |
| reg_class_contents |
| [(int) ira_reg_class_intersect[cl1][cl2]]); |
| AND_COMPL_HARD_REG_SET (temp_set2, no_unit_alloc_regs); |
| if (! hard_reg_set_subset_p (temp_hard_regset, temp_set2) |
| /* If the allocatable hard register sets are |
| the same, prefer GENERAL_REGS or the |
| smallest class for debugging |
| purposes. */ |
| || (hard_reg_set_equal_p (temp_hard_regset, temp_set2) |
| && (cl3 == GENERAL_REGS |
| || ((ira_reg_class_intersect[cl1][cl2] |
| != GENERAL_REGS) |
| && hard_reg_set_subset_p |
| (reg_class_contents[cl3], |
| reg_class_contents |
| [(int) |
| ira_reg_class_intersect[cl1][cl2]]))))) |
| ira_reg_class_intersect[cl1][cl2] = (enum reg_class) cl3; |
| } |
| COPY_HARD_REG_SET |
| (temp_set2, |
| reg_class_contents[(int) ira_reg_class_subset[cl1][cl2]]); |
| AND_COMPL_HARD_REG_SET (temp_set2, no_unit_alloc_regs); |
| if (! hard_reg_set_subset_p (temp_hard_regset, temp_set2) |
| /* Ignore unavailable hard registers and prefer |
| smallest class for debugging purposes. */ |
| || (hard_reg_set_equal_p (temp_hard_regset, temp_set2) |
| && hard_reg_set_subset_p |
| (reg_class_contents[cl3], |
| reg_class_contents |
| [(int) ira_reg_class_subset[cl1][cl2]]))) |
| ira_reg_class_subset[cl1][cl2] = (enum reg_class) cl3; |
| } |
| if (important_class_p[cl3] |
| && hard_reg_set_subset_p (temp_hard_regset, union_set)) |
| { |
| /* CL3 allocatbale hard register set is inside of |
| union of allocatable hard register sets of CL1 |
| and CL2. */ |
| COPY_HARD_REG_SET |
| (temp_set2, |
| reg_class_contents[(int) ira_reg_class_subunion[cl1][cl2]]); |
| AND_COMPL_HARD_REG_SET (temp_set2, no_unit_alloc_regs); |
| if (ira_reg_class_subunion[cl1][cl2] == NO_REGS |
| || (hard_reg_set_subset_p (temp_set2, temp_hard_regset) |
| |
| && (! hard_reg_set_equal_p (temp_set2, |
| temp_hard_regset) |
| || cl3 == GENERAL_REGS |
| /* If the allocatable hard register sets are the |
| same, prefer GENERAL_REGS or the smallest |
| class for debugging purposes. */ |
| || (ira_reg_class_subunion[cl1][cl2] != GENERAL_REGS |
| && hard_reg_set_subset_p |
| (reg_class_contents[cl3], |
| reg_class_contents |
| [(int) ira_reg_class_subunion[cl1][cl2]]))))) |
| ira_reg_class_subunion[cl1][cl2] = (enum reg_class) cl3; |
| } |
| if (hard_reg_set_subset_p (union_set, temp_hard_regset)) |
| { |
| /* CL3 allocatable hard register set contains union |
| of allocatable hard register sets of CL1 and |
| CL2. */ |
| COPY_HARD_REG_SET |
| (temp_set2, |
| reg_class_contents[(int) ira_reg_class_superunion[cl1][cl2]]); |
| AND_COMPL_HARD_REG_SET (temp_set2, no_unit_alloc_regs); |
| if (ira_reg_class_superunion[cl1][cl2] == NO_REGS |
| || (hard_reg_set_subset_p (temp_hard_regset, temp_set2) |
| |
| && (! hard_reg_set_equal_p (temp_set2, |
| temp_hard_regset) |
| || cl3 == GENERAL_REGS |
| /* If the allocatable hard register sets are the |
| same, prefer GENERAL_REGS or the smallest |
| class for debugging purposes. */ |
| || (ira_reg_class_superunion[cl1][cl2] != GENERAL_REGS |
| && hard_reg_set_subset_p |
| (reg_class_contents[cl3], |
| reg_class_contents |
| [(int) ira_reg_class_superunion[cl1][cl2]]))))) |
| ira_reg_class_superunion[cl1][cl2] = (enum reg_class) cl3; |
| } |
| } |
| } |
| } |
| } |
| |
| /* Output all unifrom and important classes into file F. */ |
| static void |
| print_unform_and_important_classes (FILE *f) |
| { |
| static const char *const reg_class_names[] = REG_CLASS_NAMES; |
| int i, cl; |
| |
| fprintf (f, "Uniform classes:\n"); |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| if (ira_uniform_class_p[cl]) |
| fprintf (f, " %s", reg_class_names[cl]); |
| fprintf (f, "\nImportant classes:\n"); |
| for (i = 0; i < ira_important_classes_num; i++) |
| fprintf (f, " %s", reg_class_names[ira_important_classes[i]]); |
| fprintf (f, "\n"); |
| } |
| |
| /* Output all possible allocno or pressure classes and their |
| translation map into file F. */ |
| static void |
| print_translated_classes (FILE *f, bool pressure_p) |
| { |
| int classes_num = (pressure_p |
| ? ira_pressure_classes_num : ira_allocno_classes_num); |
| enum reg_class *classes = (pressure_p |
| ? ira_pressure_classes : ira_allocno_classes); |
| enum reg_class *class_translate = (pressure_p |
| ? ira_pressure_class_translate |
| : ira_allocno_class_translate); |
| static const char *const reg_class_names[] = REG_CLASS_NAMES; |
| int i; |
| |
| fprintf (f, "%s classes:\n", pressure_p ? "Pressure" : "Allocno"); |
| for (i = 0; i < classes_num; i++) |
| fprintf (f, " %s", reg_class_names[classes[i]]); |
| fprintf (f, "\nClass translation:\n"); |
| for (i = 0; i < N_REG_CLASSES; i++) |
| fprintf (f, " %s -> %s\n", reg_class_names[i], |
| reg_class_names[class_translate[i]]); |
| } |
| |
| /* Output all possible allocno and translation classes and the |
| translation maps into stderr. */ |
| void |
| ira_debug_allocno_classes (void) |
| { |
| print_unform_and_important_classes (stderr); |
| print_translated_classes (stderr, false); |
| print_translated_classes (stderr, true); |
| } |
| |
| /* Set up different arrays concerning class subsets, allocno and |
| important classes. */ |
| static void |
| find_reg_classes (void) |
| { |
| setup_allocno_and_important_classes (); |
| setup_class_translate (); |
| reorder_important_classes (); |
| setup_reg_class_relations (); |
| } |
| |
| |
| |
| /* Set up the array above. */ |
| static void |
| setup_hard_regno_aclass (void) |
| { |
| int i; |
| |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| { |
| #if 1 |
| ira_hard_regno_allocno_class[i] |
| = (TEST_HARD_REG_BIT (no_unit_alloc_regs, i) |
| ? NO_REGS |
| : ira_allocno_class_translate[REGNO_REG_CLASS (i)]); |
| #else |
| int j; |
| enum reg_class cl; |
| ira_hard_regno_allocno_class[i] = NO_REGS; |
| for (j = 0; j < ira_allocno_classes_num; j++) |
| { |
| cl = ira_allocno_classes[j]; |
| if (ira_class_hard_reg_index[cl][i] >= 0) |
| { |
| ira_hard_regno_allocno_class[i] = cl; |
| break; |
| } |
| } |
| #endif |
| } |
| } |
| |
| |
| |
| /* Form IRA_REG_CLASS_MAX_NREGS and IRA_REG_CLASS_MIN_NREGS maps. */ |
| static void |
| setup_reg_class_nregs (void) |
| { |
| int i, cl, cl2, m; |
| |
| for (m = 0; m < MAX_MACHINE_MODE; m++) |
| { |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| ira_reg_class_max_nregs[cl][m] |
| = ira_reg_class_min_nregs[cl][m] |
| = targetm.class_max_nregs ((reg_class_t) cl, (enum machine_mode) m); |
| for (cl = 0; cl < N_REG_CLASSES; cl++) |
| for (i = 0; |
| (cl2 = alloc_reg_class_subclasses[cl][i]) != LIM_REG_CLASSES; |
| i++) |
| if (ira_reg_class_min_nregs[cl2][m] |
| < ira_reg_class_min_nregs[cl][m]) |
| ira_reg_class_min_nregs[cl][m] = ira_reg_class_min_nregs[cl2][m]; |
| } |
| } |
| |
| |
| |
| /* Set up IRA_PROHIBITED_CLASS_MODE_REGS and IRA_CLASS_SINGLETON. |
| This function is called once IRA_CLASS_HARD_REGS has been initialized. */ |
| static void |
| setup_prohibited_class_mode_regs (void) |
| { |
| int j, k, hard_regno, cl, last_hard_regno, count; |
| |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| { |
| COPY_HARD_REG_SET (temp_hard_regset, reg_class_contents[cl]); |
| AND_COMPL_HARD_REG_SET (temp_hard_regset, no_unit_alloc_regs); |
| for (j = 0; j < NUM_MACHINE_MODES; j++) |
| { |
| count = 0; |
| last_hard_regno = -1; |
| CLEAR_HARD_REG_SET (ira_prohibited_class_mode_regs[cl][j]); |
| for (k = ira_class_hard_regs_num[cl] - 1; k >= 0; k--) |
| { |
| hard_regno = ira_class_hard_regs[cl][k]; |
| if (! HARD_REGNO_MODE_OK (hard_regno, (enum machine_mode) j)) |
| SET_HARD_REG_BIT (ira_prohibited_class_mode_regs[cl][j], |
| hard_regno); |
| else if (in_hard_reg_set_p (temp_hard_regset, |
| (enum machine_mode) j, hard_regno)) |
| { |
| last_hard_regno = hard_regno; |
| count++; |
| } |
| } |
| ira_class_singleton[cl][j] = (count == 1 ? last_hard_regno : -1); |
| } |
| } |
| } |
| |
| /* Clarify IRA_PROHIBITED_CLASS_MODE_REGS by excluding hard registers |
| spanning from one register pressure class to another one. It is |
| called after defining the pressure classes. */ |
| static void |
| clarify_prohibited_class_mode_regs (void) |
| { |
| int j, k, hard_regno, cl, pclass, nregs; |
| |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| for (j = 0; j < NUM_MACHINE_MODES; j++) |
| { |
| CLEAR_HARD_REG_SET (ira_useful_class_mode_regs[cl][j]); |
| for (k = ira_class_hard_regs_num[cl] - 1; k >= 0; k--) |
| { |
| hard_regno = ira_class_hard_regs[cl][k]; |
| if (TEST_HARD_REG_BIT (ira_prohibited_class_mode_regs[cl][j], hard_regno)) |
| continue; |
| nregs = hard_regno_nregs[hard_regno][j]; |
| if (hard_regno + nregs > FIRST_PSEUDO_REGISTER) |
| { |
| SET_HARD_REG_BIT (ira_prohibited_class_mode_regs[cl][j], |
| hard_regno); |
| continue; |
| } |
| pclass = ira_pressure_class_translate[REGNO_REG_CLASS (hard_regno)]; |
| for (nregs-- ;nregs >= 0; nregs--) |
| if (((enum reg_class) pclass |
| != ira_pressure_class_translate[REGNO_REG_CLASS |
| (hard_regno + nregs)])) |
| { |
| SET_HARD_REG_BIT (ira_prohibited_class_mode_regs[cl][j], |
| hard_regno); |
| break; |
| } |
| if (!TEST_HARD_REG_BIT (ira_prohibited_class_mode_regs[cl][j], |
| hard_regno)) |
| add_to_hard_reg_set (&ira_useful_class_mode_regs[cl][j], |
| (enum machine_mode) j, hard_regno); |
| } |
| } |
| } |
| |
| /* Allocate and initialize IRA_REGISTER_MOVE_COST, IRA_MAY_MOVE_IN_COST |
| and IRA_MAY_MOVE_OUT_COST for MODE. */ |
| void |
| ira_init_register_move_cost (enum machine_mode mode) |
| { |
| static unsigned short last_move_cost[N_REG_CLASSES][N_REG_CLASSES]; |
| bool all_match = true; |
| unsigned int cl1, cl2; |
| |
| ira_assert (ira_register_move_cost[mode] == NULL |
| && ira_may_move_in_cost[mode] == NULL |
| && ira_may_move_out_cost[mode] == NULL); |
| ira_assert (have_regs_of_mode[mode]); |
| for (cl1 = 0; cl1 < N_REG_CLASSES; cl1++) |
| for (cl2 = 0; cl2 < N_REG_CLASSES; cl2++) |
| { |
| int cost; |
| if (!contains_reg_of_mode[cl1][mode] |
| || !contains_reg_of_mode[cl2][mode]) |
| { |
| if ((ira_reg_class_max_nregs[cl1][mode] |
| > ira_class_hard_regs_num[cl1]) |
| || (ira_reg_class_max_nregs[cl2][mode] |
| > ira_class_hard_regs_num[cl2])) |
| cost = 65535; |
| else |
| cost = (ira_memory_move_cost[mode][cl1][0] |
| + ira_memory_move_cost[mode][cl2][1]) * 2; |
| } |
| else |
| { |
| cost = register_move_cost (mode, (enum reg_class) cl1, |
| (enum reg_class) cl2); |
| ira_assert (cost < 65535); |
| } |
| all_match &= (last_move_cost[cl1][cl2] == cost); |
| last_move_cost[cl1][cl2] = cost; |
| } |
| if (all_match && last_mode_for_init_move_cost != -1) |
| { |
| ira_register_move_cost[mode] |
| = ira_register_move_cost[last_mode_for_init_move_cost]; |
| ira_may_move_in_cost[mode] |
| = ira_may_move_in_cost[last_mode_for_init_move_cost]; |
| ira_may_move_out_cost[mode] |
| = ira_may_move_out_cost[last_mode_for_init_move_cost]; |
| return; |
| } |
| last_mode_for_init_move_cost = mode; |
| ira_register_move_cost[mode] = XNEWVEC (move_table, N_REG_CLASSES); |
| ira_may_move_in_cost[mode] = XNEWVEC (move_table, N_REG_CLASSES); |
| ira_may_move_out_cost[mode] = XNEWVEC (move_table, N_REG_CLASSES); |
| for (cl1 = 0; cl1 < N_REG_CLASSES; cl1++) |
| for (cl2 = 0; cl2 < N_REG_CLASSES; cl2++) |
| { |
| int cost; |
| enum reg_class *p1, *p2; |
| |
| if (last_move_cost[cl1][cl2] == 65535) |
| { |
| ira_register_move_cost[mode][cl1][cl2] = 65535; |
| ira_may_move_in_cost[mode][cl1][cl2] = 65535; |
| ira_may_move_out_cost[mode][cl1][cl2] = 65535; |
| } |
| else |
| { |
| cost = last_move_cost[cl1][cl2]; |
| |
| for (p2 = ®_class_subclasses[cl2][0]; |
| *p2 != LIM_REG_CLASSES; p2++) |
| if (ira_class_hard_regs_num[*p2] > 0 |
| && (ira_reg_class_max_nregs[*p2][mode] |
| <= ira_class_hard_regs_num[*p2])) |
| cost = MAX (cost, ira_register_move_cost[mode][cl1][*p2]); |
| |
| for (p1 = ®_class_subclasses[cl1][0]; |
| *p1 != LIM_REG_CLASSES; p1++) |
| if (ira_class_hard_regs_num[*p1] > 0 |
| && (ira_reg_class_max_nregs[*p1][mode] |
| <= ira_class_hard_regs_num[*p1])) |
| cost = MAX (cost, ira_register_move_cost[mode][*p1][cl2]); |
| |
| ira_assert (cost <= 65535); |
| ira_register_move_cost[mode][cl1][cl2] = cost; |
| |
| if (ira_class_subset_p[cl1][cl2]) |
| ira_may_move_in_cost[mode][cl1][cl2] = 0; |
| else |
| ira_may_move_in_cost[mode][cl1][cl2] = cost; |
| |
| if (ira_class_subset_p[cl2][cl1]) |
| ira_may_move_out_cost[mode][cl1][cl2] = 0; |
| else |
| ira_may_move_out_cost[mode][cl1][cl2] = cost; |
| } |
| } |
| } |
| |
| |
| |
| /* This is called once during compiler work. It sets up |
| different arrays whose values don't depend on the compiled |
| function. */ |
| void |
| ira_init_once (void) |
| { |
| ira_init_costs_once (); |
| lra_init_once (); |
| } |
| |
| /* Free ira_max_register_move_cost, ira_may_move_in_cost and |
| ira_may_move_out_cost for each mode. */ |
| static void |
| free_register_move_costs (void) |
| { |
| int mode, i; |
| |
| /* Reset move_cost and friends, making sure we only free shared |
| table entries once. */ |
| for (mode = 0; mode < MAX_MACHINE_MODE; mode++) |
| if (ira_register_move_cost[mode]) |
| { |
| for (i = 0; |
| i < mode && (ira_register_move_cost[i] |
| != ira_register_move_cost[mode]); |
| i++) |
| ; |
| if (i == mode) |
| { |
| free (ira_register_move_cost[mode]); |
| free (ira_may_move_in_cost[mode]); |
| free (ira_may_move_out_cost[mode]); |
| } |
| } |
| memset (ira_register_move_cost, 0, sizeof ira_register_move_cost); |
| memset (ira_may_move_in_cost, 0, sizeof ira_may_move_in_cost); |
| memset (ira_may_move_out_cost, 0, sizeof ira_may_move_out_cost); |
| last_mode_for_init_move_cost = -1; |
| } |
| |
| /* This is called every time when register related information is |
| changed. */ |
| void |
| ira_init (void) |
| { |
| free_register_move_costs (); |
| setup_reg_mode_hard_regset (); |
| setup_alloc_regs (flag_omit_frame_pointer != 0 |
| || flag_shrink_wrap_frame_pointer); |
| setup_class_subset_and_memory_move_costs (); |
| setup_reg_class_nregs (); |
| setup_prohibited_class_mode_regs (); |
| find_reg_classes (); |
| clarify_prohibited_class_mode_regs (); |
| setup_hard_regno_aclass (); |
| ira_init_costs (); |
| lra_init (); |
| } |
| |
| /* Function called once at the end of compiler work. */ |
| void |
| ira_finish_once (void) |
| { |
| ira_finish_costs_once (); |
| free_register_move_costs (); |
| lra_finish_once (); |
| } |
| |
| |
| #define ira_prohibited_mode_move_regs_initialized_p \ |
| (this_target_ira_int->x_ira_prohibited_mode_move_regs_initialized_p) |
| |
| /* Set up IRA_PROHIBITED_MODE_MOVE_REGS. */ |
| static void |
| setup_prohibited_mode_move_regs (void) |
| { |
| int i, j; |
| rtx test_reg1, test_reg2, move_pat, move_insn; |
| |
| if (ira_prohibited_mode_move_regs_initialized_p) |
| return; |
| ira_prohibited_mode_move_regs_initialized_p = true; |
| test_reg1 = gen_rtx_REG (VOIDmode, 0); |
| test_reg2 = gen_rtx_REG (VOIDmode, 0); |
| move_pat = gen_rtx_SET (VOIDmode, test_reg1, test_reg2); |
| move_insn = gen_rtx_INSN (VOIDmode, 0, 0, 0, 0, move_pat, 0, -1, 0); |
| for (i = 0; i < NUM_MACHINE_MODES; i++) |
| { |
| SET_HARD_REG_SET (ira_prohibited_mode_move_regs[i]); |
| for (j = 0; j < FIRST_PSEUDO_REGISTER; j++) |
| { |
| if (! HARD_REGNO_MODE_OK (j, (enum machine_mode) i)) |
| continue; |
| SET_REGNO_RAW (test_reg1, j); |
| PUT_MODE (test_reg1, (enum machine_mode) i); |
| SET_REGNO_RAW (test_reg2, j); |
| PUT_MODE (test_reg2, (enum machine_mode) i); |
| INSN_CODE (move_insn) = -1; |
| recog_memoized (move_insn); |
| if (INSN_CODE (move_insn) < 0) |
| continue; |
| extract_insn (move_insn); |
| if (! constrain_operands (1)) |
| continue; |
| CLEAR_HARD_REG_BIT (ira_prohibited_mode_move_regs[i], j); |
| } |
| } |
| } |
| |
| |
| |
| /* Return TRUE if the operand constraint STR is commutative. */ |
| static bool |
| commutative_constraint_p (const char *str) |
| { |
| int curr_alt, c; |
| bool ignore_p; |
| |
| for (ignore_p = false, curr_alt = 0;;) |
| { |
| c = *str; |
| if (c == '\0') |
| break; |
| str += CONSTRAINT_LEN (c, str); |
| if (c == '#' || !recog_data.alternative_enabled_p[curr_alt]) |
| ignore_p = true; |
| else if (c == ',') |
| { |
| curr_alt++; |
| ignore_p = false; |
| } |
| else if (! ignore_p) |
| { |
| /* Usually `%' is the first constraint character but the |
| documentation does not require this. */ |
| if (c == '%') |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /* Setup possible alternatives in ALTS for INSN. */ |
| void |
| ira_setup_alts (rtx insn, HARD_REG_SET &alts) |
| { |
| /* MAP nalt * nop -> start of constraints for given operand and |
| alternative */ |
| static vec<const char *> insn_constraints; |
| int nop, nalt; |
| bool curr_swapped; |
| const char *p; |
| rtx op; |
| int commutative = -1; |
| |
| extract_insn (insn); |
| CLEAR_HARD_REG_SET (alts); |
| insn_constraints.release (); |
| insn_constraints.safe_grow_cleared (recog_data.n_operands |
| * recog_data.n_alternatives + 1); |
| /* Check that the hard reg set is enough for holding all |
| alternatives. It is hard to imagine the situation when the |
| assertion is wrong. */ |
| ira_assert (recog_data.n_alternatives |
| <= (int) MAX (sizeof (HARD_REG_ELT_TYPE) * CHAR_BIT, |
| FIRST_PSEUDO_REGISTER)); |
| for (curr_swapped = false;; curr_swapped = true) |
| { |
| /* Calculate some data common for all alternatives to speed up the |
| function. */ |
| for (nop = 0; nop < recog_data.n_operands; nop++) |
| { |
| for (nalt = 0, p = recog_data.constraints[nop]; |
| nalt < recog_data.n_alternatives; |
| nalt++) |
| { |
| insn_constraints[nop * recog_data.n_alternatives + nalt] = p; |
| while (*p && *p != ',') |
| p++; |
| if (*p) |
| p++; |
| } |
| } |
| for (nalt = 0; nalt < recog_data.n_alternatives; nalt++) |
| { |
| if (! recog_data.alternative_enabled_p[nalt] || TEST_HARD_REG_BIT (alts, nalt)) |
| continue; |
| |
| for (nop = 0; nop < recog_data.n_operands; nop++) |
| { |
| int c, len; |
| |
| op = recog_data.operand[nop]; |
| p = insn_constraints[nop * recog_data.n_alternatives + nalt]; |
| if (*p == 0 || *p == ',') |
| continue; |
| |
| do |
| switch (c = *p, len = CONSTRAINT_LEN (c, p), c) |
| { |
| case '#': |
| case ',': |
| c = '\0'; |
| case '\0': |
| len = 0; |
| break; |
| |
| case '?': case '!': case '*': case '=': case '+': |
| break; |
| |
| case '%': |
| /* We only support one commutative marker, the |
| first one. We already set commutative |
| above. */ |
| if (commutative < 0) |
| commutative = nop; |
| break; |
| |
| case '&': |
| break; |
| |
| case '0': case '1': case '2': case '3': case '4': |
| case '5': case '6': case '7': case '8': case '9': |
| goto op_success; |
| break; |
| |
| case 'p': |
| case 'g': |
| case 'X': |
| case TARGET_MEM_CONSTRAINT: |
| goto op_success; |
| break; |
| |
| case '<': |
| if (MEM_P (op) |
| && (GET_CODE (XEXP (op, 0)) == PRE_DEC |
| || GET_CODE (XEXP (op, 0)) == POST_DEC)) |
| goto op_success; |
| break; |
| |
| case '>': |
| if (MEM_P (op) |
| && (GET_CODE (XEXP (op, 0)) == PRE_INC |
| || GET_CODE (XEXP (op, 0)) == POST_INC)) |
| goto op_success; |
| break; |
| |
| case 'E': |
| case 'F': |
| if (CONST_DOUBLE_AS_FLOAT_P (op) |
| || (GET_CODE (op) == CONST_VECTOR |
| && GET_MODE_CLASS (GET_MODE (op)) == MODE_VECTOR_FLOAT)) |
| goto op_success; |
| break; |
| |
| case 'G': |
| case 'H': |
| if (CONST_DOUBLE_AS_FLOAT_P (op) |
| && CONST_DOUBLE_OK_FOR_CONSTRAINT_P (op, c, p)) |
| goto op_success; |
| break; |
| |
| case 's': |
| if (CONST_SCALAR_INT_P (op)) |
| break; |
| case 'i': |
| if (CONSTANT_P (op)) |
| goto op_success; |
| break; |
| |
| case 'n': |
| if (CONST_SCALAR_INT_P (op)) |
| goto op_success; |
| break; |
| |
| case 'I': |
| case 'J': |
| case 'K': |
| case 'L': |
| case 'M': |
| case 'N': |
| case 'O': |
| case 'P': |
| if (CONST_INT_P (op) |
| && CONST_OK_FOR_CONSTRAINT_P (INTVAL (op), c, p)) |
| goto op_success; |
| break; |
| |
| case 'V': |
| if (MEM_P (op) && ! offsettable_memref_p (op)) |
| goto op_success; |
| break; |
| |
| case 'o': |
| goto op_success; |
| break; |
| |
| default: |
| { |
| enum reg_class cl; |
| |
| cl = (c == 'r' ? GENERAL_REGS : REG_CLASS_FROM_CONSTRAINT (c, p)); |
| if (cl != NO_REGS) |
| goto op_success; |
| #ifdef EXTRA_CONSTRAINT_STR |
| else if (EXTRA_CONSTRAINT_STR (op, c, p)) |
| goto op_success; |
| else if (EXTRA_MEMORY_CONSTRAINT (c, p)) |
| goto op_success; |
| else if (EXTRA_ADDRESS_CONSTRAINT (c, p)) |
| goto op_success; |
| #endif |
| break; |
| } |
| } |
| while (p += len, c); |
| break; |
| op_success: |
| ; |
| } |
| if (nop >= recog_data.n_operands) |
| SET_HARD_REG_BIT (alts, nalt); |
| } |
| if (commutative < 0) |
| break; |
| if (curr_swapped) |
| break; |
| op = recog_data.operand[commutative]; |
| recog_data.operand[commutative] = recog_data.operand[commutative + 1]; |
| recog_data.operand[commutative + 1] = op; |
| |
| } |
| } |
| |
| /* Return the number of the output non-early clobber operand which |
| should be the same in any case as operand with number OP_NUM (or |
| negative value if there is no such operand). The function takes |
| only really possible alternatives into consideration. */ |
| int |
| ira_get_dup_out_num (int op_num, HARD_REG_SET &alts) |
| { |
| int curr_alt, c, original, dup; |
| bool ignore_p, use_commut_op_p; |
| const char *str; |
| #ifdef EXTRA_CONSTRAINT_STR |
| rtx op; |
| #endif |
| |
| if (op_num < 0 || recog_data.n_alternatives == 0) |
| return -1; |
| use_commut_op_p = false; |
| str = recog_data.constraints[op_num]; |
| for (;;) |
| { |
| #ifdef EXTRA_CONSTRAINT_STR |
| op = recog_data.operand[op_num]; |
| #endif |
| |
| for (ignore_p = false, original = -1, curr_alt = 0;;) |
| { |
| c = *str; |
| if (c == '\0') |
| break; |
| if (c == '#' || !TEST_HARD_REG_BIT (alts, curr_alt)) |
| ignore_p = true; |
| else if (c == ',') |
| { |
| curr_alt++; |
| ignore_p = false; |
| } |
| else if (! ignore_p) |
| switch (c) |
| { |
| /* We should find duplications only for input operands. */ |
| case '=': |
| case '+': |
| goto fail; |
| case 'X': |
| case 'p': |
| case 'g': |
| goto fail; |
| case 'r': |
| case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': |
| case 'h': case 'j': case 'k': case 'l': |
| case 'q': case 't': case 'u': |
| case 'v': case 'w': case 'x': case 'y': case 'z': |
| case 'A': case 'B': case 'C': case 'D': |
| case 'Q': case 'R': case 'S': case 'T': case 'U': |
| case 'W': case 'Y': case 'Z': |
| { |
| enum reg_class cl; |
| |
| cl = (c == 'r' |
| ? GENERAL_REGS : REG_CLASS_FROM_CONSTRAINT (c, str)); |
| if (cl != NO_REGS) |
| { |
| if (! targetm.class_likely_spilled_p (cl)) |
| goto fail; |
| } |
| #ifdef EXTRA_CONSTRAINT_STR |
| else if (EXTRA_CONSTRAINT_STR (op, c, str)) |
| goto fail; |
| #endif |
| break; |
| } |
| |
| case '0': case '1': case '2': case '3': case '4': |
| case '5': case '6': case '7': case '8': case '9': |
| if (original != -1 && original != c) |
| goto fail; |
| original = c; |
| break; |
| } |
| str += CONSTRAINT_LEN (c, str); |
| } |
| if (original == -1) |
| goto fail; |
| dup = -1; |
| for (ignore_p = false, str = recog_data.constraints[original - '0']; |
| *str != 0; |
| str++) |
| if (ignore_p) |
| { |
| if (*str == ',') |
| ignore_p = false; |
| } |
| else if (*str == '#') |
| ignore_p = true; |
| else if (! ignore_p) |
| { |
| if (*str == '=') |
| dup = original - '0'; |
| /* It is better ignore an alternative with early clobber. */ |
| else if (*str == '&') |
| goto fail; |
| } |
| if (dup >= 0) |
| return dup; |
| fail: |
| if (use_commut_op_p) |
| break; |
| use_commut_op_p = true; |
| if (commutative_constraint_p (recog_data.constraints[op_num])) |
| str = recog_data.constraints[op_num + 1]; |
| else if (op_num > 0 && commutative_constraint_p (recog_data.constraints |
| [op_num - 1])) |
| str = recog_data.constraints[op_num - 1]; |
| else |
| break; |
| } |
| return -1; |
| } |
| |
| |
| |
| /* Search forward to see if the source register of a copy insn dies |
| before either it or the destination register is modified, but don't |
| scan past the end of the basic block. If so, we can replace the |
| source with the destination and let the source die in the copy |
| insn. |
| |
| This will reduce the number of registers live in that range and may |
| enable the destination and the source coalescing, thus often saving |
| one register in addition to a register-register copy. */ |
| |
| static void |
| decrease_live_ranges_number (void) |
| { |
| basic_block bb; |
| rtx insn, set, src, dest, dest_death, p, q, note; |
| int sregno, dregno; |
| |
| if (! flag_expensive_optimizations) |
| return; |
| |
| if (ira_dump_file) |
| fprintf (ira_dump_file, "Starting decreasing number of live ranges...\n"); |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| FOR_BB_INSNS (bb, insn) |
| { |
| set = single_set (insn); |
| if (! set) |
| continue; |
| src = SET_SRC (set); |
| dest = SET_DEST (set); |
| if (! REG_P (src) || ! REG_P (dest) |
| || find_reg_note (insn, REG_DEAD, src)) |
| continue; |
| sregno = REGNO (src); |
| dregno = REGNO (dest); |
| |
| /* We don't want to mess with hard regs if register classes |
| are small. */ |
| if (sregno == dregno |
| || (targetm.small_register_classes_for_mode_p (GET_MODE (src)) |
| && (sregno < FIRST_PSEUDO_REGISTER |
| || dregno < FIRST_PSEUDO_REGISTER)) |
| /* We don't see all updates to SP if they are in an |
| auto-inc memory reference, so we must disallow this |
| optimization on them. */ |
| || sregno == STACK_POINTER_REGNUM |
| || dregno == STACK_POINTER_REGNUM) |
| continue; |
| |
| dest_death = NULL_RTX; |
| |
| for (p = NEXT_INSN (insn); p; p = NEXT_INSN (p)) |
| { |
| if (! INSN_P (p)) |
| continue; |
| if (BLOCK_FOR_INSN (p) != bb) |
| break; |
| |
| if (reg_set_p (src, p) || reg_set_p (dest, p) |
| /* If SRC is an asm-declared register, it must not be |
| replaced in any asm. Unfortunately, the REG_EXPR |
| tree for the asm variable may be absent in the SRC |
| rtx, so we can't check the actual register |
| declaration easily (the asm operand will have it, |
| though). To avoid complicating the test for a rare |
| case, we just don't perform register replacement |
| for a hard reg mentioned in an asm. */ |
| || (sregno < FIRST_PSEUDO_REGISTER |
| && asm_noperands (PATTERN (p)) >= 0 |
| && reg_overlap_mentioned_p (src, PATTERN (p))) |
| /* Don't change hard registers used by a call. */ |
| || (CALL_P (p) && sregno < FIRST_PSEUDO_REGISTER |
| && find_reg_fusage (p, USE, src)) |
| /* Don't change a USE of a register. */ |
| || (GET_CODE (PATTERN (p)) == USE |
| && reg_overlap_mentioned_p (src, XEXP (PATTERN (p), 0)))) |
| break; |
| |
| /* See if all of SRC dies in P. This test is slightly |
| more conservative than it needs to be. */ |
| if ((note = find_regno_note (p, REG_DEAD, sregno)) |
| && GET_MODE (XEXP (note, 0)) == GET_MODE (src)) |
| { |
| int failed = 0; |
| |
| /* We can do the optimization. Scan forward from INSN |
| again, replacing regs as we go. Set FAILED if a |
| replacement can't be done. In that case, we can't |
| move the death note for SRC. This should be |
| rare. */ |
| |
| /* Set to stop at next insn. */ |
| for (q = next_real_insn (insn); |
| q != next_real_insn (p); |
| q = next_real_insn (q)) |
| { |
| if (reg_overlap_mentioned_p (src, PATTERN (q))) |
| { |
| /* If SRC is a hard register, we might miss |
| some overlapping registers with |
| validate_replace_rtx, so we would have to |
| undo it. We can't if DEST is present in |
| the insn, so fail in that combination of |
| cases. */ |
| if (sregno < FIRST_PSEUDO_REGISTER |
| && reg_mentioned_p (dest, PATTERN (q))) |
| failed = 1; |
| |
| /* Attempt to replace all uses. */ |
| else if (!validate_replace_rtx (src, dest, q)) |
| failed = 1; |
| |
| /* If this succeeded, but some part of the |
| register is still present, undo the |
| replacement. */ |
| else if (sregno < FIRST_PSEUDO_REGISTER |
| && reg_overlap_mentioned_p (src, PATTERN (q))) |
| { |
| validate_replace_rtx (dest, src, q); |
| failed = 1; |
| } |
| } |
| |
| /* If DEST dies here, remove the death note and |
| save it for later. Make sure ALL of DEST dies |
| here; again, this is overly conservative. */ |
| if (! dest_death |
| && (dest_death = find_regno_note (q, REG_DEAD, dregno))) |
| { |
| if (GET_MODE (XEXP (dest_death, 0)) == GET_MODE (dest)) |
| remove_note (q, dest_death); |
| else |
| { |
| failed = 1; |
| dest_death = 0; |
| } |
| } |
| } |
| |
| if (! failed) |
| { |
| /* Move death note of SRC from P to INSN. */ |
| remove_note (p, note); |
| XEXP (note, 1) = REG_NOTES (insn); |
| REG_NOTES (insn) = note; |
| } |
| |
| /* DEST is also dead if INSN has a REG_UNUSED note for |
| DEST. */ |
| if (! dest_death |
| && (dest_death |
| = find_regno_note (insn, REG_UNUSED, dregno))) |
| { |
| PUT_REG_NOTE_KIND (dest_death, REG_DEAD); |
| remove_note (insn, dest_death); |
| } |
| |
| /* Put death note of DEST on P if we saw it die. */ |
| if (dest_death) |
| { |
| XEXP (dest_death, 1) = REG_NOTES (p); |
| REG_NOTES (p) = dest_death; |
| } |
| break; |
| } |
| |
| /* If SRC is a hard register which is set or killed in |
| some other way, we can't do this optimization. */ |
| else if (sregno < FIRST_PSEUDO_REGISTER && dead_or_set_p (p, src)) |
| break; |
| } |
| } |
| } |
| |
| |
| |
| /* Return nonzero if REGNO is a particularly bad choice for reloading X. */ |
| static bool |
| ira_bad_reload_regno_1 (int regno, rtx x) |
| { |
| int x_regno, n, i; |
| ira_allocno_t a; |
| enum reg_class pref; |
| |
| /* We only deal with pseudo regs. */ |
| if (! x || GET_CODE (x) != REG) |
| return false; |
| |
| x_regno = REGNO (x); |
| if (x_regno < FIRST_PSEUDO_REGISTER) |
| return false; |
| |
| /* If the pseudo prefers REGNO explicitly, then do not consider |
| REGNO a bad spill choice. */ |
| pref = reg_preferred_class (x_regno); |
| if (reg_class_size[pref] == 1) |
| return !TEST_HARD_REG_BIT (reg_class_contents[pref], regno); |
| |
| /* If the pseudo conflicts with REGNO, then we consider REGNO a |
| poor choice for a reload regno. */ |
| a = ira_regno_allocno_map[x_regno]; |
| n = ALLOCNO_NUM_OBJECTS (a); |
| for (i = 0; i < n; i++) |
| { |
| ira_object_t obj = ALLOCNO_OBJECT (a, i); |
| if (TEST_HARD_REG_BIT (OBJECT_TOTAL_CONFLICT_HARD_REGS (obj), regno)) |
| return true; |
| } |
| return false; |
| } |
| |
| /* Return nonzero if REGNO is a particularly bad choice for reloading |
| IN or OUT. */ |
| bool |
| ira_bad_reload_regno (int regno, rtx in, rtx out) |
| { |
| return (ira_bad_reload_regno_1 (regno, in) |
| || ira_bad_reload_regno_1 (regno, out)); |
| } |
| |
| /* Return TRUE if *LOC contains an asm. */ |
| static int |
| insn_contains_asm_1 (rtx *loc, void *data ATTRIBUTE_UNUSED) |
| { |
| if ( !*loc) |
| return FALSE; |
| if (GET_CODE (*loc) == ASM_OPERANDS) |
| return TRUE; |
| return FALSE; |
| } |
| |
| |
| /* Return TRUE if INSN contains an ASM. */ |
| static bool |
| insn_contains_asm (rtx insn) |
| { |
| return for_each_rtx (&insn, insn_contains_asm_1, NULL); |
| } |
| |
| /* Add register clobbers from asm statements. */ |
| static void |
| compute_regs_asm_clobbered (void) |
| { |
| basic_block bb; |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| rtx insn; |
| FOR_BB_INSNS_REVERSE (bb, insn) |
| { |
| df_ref *def_rec; |
| |
| if (insn_contains_asm (insn)) |
| for (def_rec = DF_INSN_DEFS (insn); *def_rec; def_rec++) |
| { |
| df_ref def = *def_rec; |
| unsigned int dregno = DF_REF_REGNO (def); |
| if (HARD_REGISTER_NUM_P (dregno)) |
| add_to_hard_reg_set (&crtl->asm_clobbers, |
| GET_MODE (DF_REF_REAL_REG (def)), |
| dregno); |
| } |
| } |
| } |
| } |
| |
| |
| /* Set up ELIMINABLE_REGSET, IRA_NO_ALLOC_REGS, and |
| REGS_EVER_LIVE. */ |
| void |
| ira_setup_eliminable_regset (void) |
| { |
| #ifdef ELIMINABLE_REGS |
| int i; |
| static const struct {const int from, to; } eliminables[] = ELIMINABLE_REGS; |
| #endif |
| bool can_omit_leaf_frame_pointer = targetm.can_omit_leaf_frame_pointer (); |
| frame_pointer_partially_needed = flag_shrink_wrap_frame_pointer |
| && crtl->sp_is_unchanging |
| && !can_omit_leaf_frame_pointer; |
| |
| /* FIXME: If EXIT_IGNORE_STACK is set, we will not save and restore |
| sp for alloca. So we can't eliminate the frame pointer in that |
| case. At some point, we should improve this by emitting the |
| sp-adjusting insns for this case. */ |
| frame_pointer_needed |
| = ((!flag_omit_frame_pointer |
| && !frame_pointer_partially_needed |
| && !can_omit_leaf_frame_pointer) |
| || (cfun->calls_alloca && EXIT_IGNORE_STACK) |
| /* We need the frame pointer to catch stack overflow exceptions |
| if the stack pointer is moving. */ |
| || (flag_stack_check && STACK_CHECK_MOVING_SP) |
| || crtl->accesses_prior_frames |
| || (SUPPORTS_STACK_ALIGNMENT && crtl->stack_realign_needed) |
| /* We need a frame pointer for all Cilk Plus functions that use |
| Cilk keywords. */ |
| || (flag_cilkplus && cfun->is_cilk_function) |
| || targetm.frame_pointer_required ()); |
| |
| /* The chance that FRAME_POINTER_NEEDED is changed from inspecting |
| RTL is very small. So if we use frame pointer for RA and RTL |
| actually prevents this, we will spill pseudos assigned to the |
| frame pointer in LRA. */ |
| |
| if (frame_pointer_needed) |
| df_set_regs_ever_live (HARD_FRAME_POINTER_REGNUM, true); |
| |
| COPY_HARD_REG_SET (ira_no_alloc_regs, no_unit_alloc_regs); |
| CLEAR_HARD_REG_SET (eliminable_regset); |
| |
| compute_regs_asm_clobbered (); |
| |
| /* Build the regset of all eliminable registers and show we can't |
| use those that we already know won't be eliminated. */ |
| #ifdef ELIMINABLE_REGS |
| for (i = 0; i < (int) ARRAY_SIZE (eliminables); i++) |
| { |
| bool cannot_elim |
| = (! targetm.can_eliminate (eliminables[i].from, eliminables[i].to) |
| || (eliminables[i].to == STACK_POINTER_REGNUM && frame_pointer_needed)); |
| |
| if (!TEST_HARD_REG_BIT (crtl->asm_clobbers, eliminables[i].from)) |
| { |
| SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from); |
| |
| if (cannot_elim) |
| SET_HARD_REG_BIT (ira_no_alloc_regs, eliminables[i].from); |
| } |
| else if (cannot_elim) |
| error ("%s cannot be used in asm here", |
| reg_names[eliminables[i].from]); |
| else |
| df_set_regs_ever_live (eliminables[i].from, true); |
| } |
| #if !HARD_FRAME_POINTER_IS_FRAME_POINTER |
| if (!TEST_HARD_REG_BIT (crtl->asm_clobbers, HARD_FRAME_POINTER_REGNUM)) |
| { |
| SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM); |
| if (frame_pointer_needed) |
| SET_HARD_REG_BIT (ira_no_alloc_regs, HARD_FRAME_POINTER_REGNUM); |
| } |
| else if (frame_pointer_needed) |
| error ("%s cannot be used in asm here", |
| reg_names[HARD_FRAME_POINTER_REGNUM]); |
| else |
| df_set_regs_ever_live (HARD_FRAME_POINTER_REGNUM, true); |
| #endif |
| |
| #else |
| if (!TEST_HARD_REG_BIT (crtl->asm_clobbers, HARD_FRAME_POINTER_REGNUM)) |
| { |
| SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM); |
| if (frame_pointer_needed) |
| SET_HARD_REG_BIT (ira_no_alloc_regs, FRAME_POINTER_REGNUM); |
| } |
| else if (frame_pointer_needed) |
| error ("%s cannot be used in asm here", reg_names[FRAME_POINTER_REGNUM]); |
| else |
| df_set_regs_ever_live (FRAME_POINTER_REGNUM, true); |
| #endif |
| } |
| |
| /* Adjust frame pointer's alloc order. ALLOC_FIRST means giving fp |
| reg first allocation order. !ALLOC_FIRST means giving fp reg last |
| allocation order. */ |
| |
| void |
| adjust_fp_alloc_order (bool alloc_first) |
| { |
| int cl, i, hard_regno; |
| |
| hard_regno = HARD_FRAME_POINTER_REGNUM; |
| for (cl = (int) N_REG_CLASSES - 1; cl >= 0; cl--) |
| { |
| int fp_index; |
| |
| if (!TEST_HARD_REG_BIT (reg_class_contents[cl], hard_regno)) |
| continue; |
| |
| fp_index = ira_class_hard_reg_index[cl][hard_regno]; |
| if (alloc_first) |
| { |
| for (i = fp_index; i > 0; i--) |
| { |
| int hard_reg_tmp; |
| hard_reg_tmp = ira_class_hard_regs[cl][i-1]; |
| ira_class_hard_regs[cl][i] = hard_reg_tmp; |
| ira_class_hard_reg_index[cl][hard_reg_tmp] = i; |
| } |
| ira_class_hard_regs[cl][0] = hard_regno; |
| ira_class_hard_reg_index[cl][hard_regno] = 0; |
| } |
| else |
| { |
| int class_size = ira_class_hard_regs_num[cl]; |
| for (i = fp_index; i < class_size - 1; i++) |
| { |
| int hard_reg_tmp; |
| hard_reg_tmp = ira_class_hard_regs[cl][i+1]; |
| ira_class_hard_regs[cl][i] = hard_reg_tmp; |
| ira_class_hard_reg_index[cl][hard_reg_tmp] = i; |
| } |
| ira_class_hard_regs[cl][class_size - 1] = hard_regno; |
| ira_class_hard_reg_index[cl][hard_regno] = class_size - 1; |
| } |
| } |
| /* Do we have to reorder reg_alloc_order to make it consistent |
| with ira_class_hard_regs? */ |
| } |
| |
| /* Set frame pointer to be call used. */ |
| static void |
| set_fp_to_call_used () |
| { |
| int fp = HARD_FRAME_POINTER_REGNUM; |
| call_used_regs[fp] = true; |
| SET_HARD_REG_BIT (call_used_reg_set, fp); |
| } |
| |
| /* Reset frame pointer to be call used. */ |
| static void |
| reset_fp_to_call_used () |
| { |
| int fp = HARD_FRAME_POINTER_REGNUM; |
| call_used_regs[fp] = false; |
| CLEAR_HARD_REG_BIT (call_used_reg_set, fp); |
| } |
| |
| /* FP shrinkwrapping optimization: |
| Between -fomit-frame-pointer and -fno-omit-frame-pointer, |
| -fpartial-omit-frame-pointer is introduced to do fp shrinkwrapping. |
| In -fno-omit-frame-pointer case, fp is dedicately used to keep the |
| stack frame chain from caller to callee and enable fast stack |
| backtracing. In -fomit-frame-pointer case, fp is dedicately used as |
| a free callee-saved register. In -fpartial-omit-frame-pointer case, |
| fp has two fold usages: it is not only used as the register to pass |
| frame address of caller to callee, but also used as a caller-saved |
| register, so we can achieve of the best of both worlds. But these |
| two usages are conflicted with each other -- using fp as a free |
| register in a hot loop could inhibit frame address saving insn |
| (called as fp setting later) before a call inside the loop from being |
| promoted to the loop preheader. So loop regions in a function should |
| be partitioned for different fp usages. In IRA phase, there is a cost |
| evaluation function to partition all the loops to two sets: either use |
| fp freely or not. LRA will follow the evaluation decision in IRA. In |
| pro_and_epilogue phase, fp setting will be inserted immediately before |
| each call initially, and if IRA and LRA don't generate any normal fp |
| usage in a loop, fp shrinkwrapping could reduce the fp setting cost |
| by promoting it outside of the loop. */ |
| |
| void |
| ira_init_partial_omit_fp () |
| { |
| /* If frame_pointer_needed is true, give up fp-shrinkwrapping. */ |
| if (frame_pointer_needed) |
| frame_pointer_partially_needed = false; |
| |
| if (frame_pointer_partially_needed) |
| { |
| set_fp_to_call_used (); |
| #ifdef REG_ALLOC_ORDER |
| /* In fp shrinkwrapping, fp is expected to be used in |
| the lowest priority in GENERAL_REGS. */ |
| adjust_fp_alloc_order (false); |
| #endif |
| } |
| else |
| { |
| reset_fp_to_call_used (); |
| return; |
| } |
| } |
| |
| /* Vector of substitutions of register numbers, |
| used to map pseudo regs into hardware regs. |
| This is set up as a result of register allocation. |
| Element N is the hard reg assigned to pseudo reg N, |
| or is -1 if no hard reg was assigned. |
| If N is a hard reg number, element N is N. */ |
| short *reg_renumber; |
| |
| /* Set up REG_RENUMBER and CALLER_SAVE_NEEDED (used by reload) from |
| the allocation found by IRA. */ |
| static void |
| setup_reg_renumber (void) |
| { |
| int regno, hard_regno; |
| ira_allocno_t a; |
| ira_allocno_iterator ai; |
| |
| caller_save_needed = 0; |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| if (ira_use_lra_p && ALLOCNO_CAP_MEMBER (a) != NULL) |
| continue; |
| /* There are no caps at this point. */ |
| ira_assert (ALLOCNO_CAP_MEMBER (a) == NULL); |
| if (! ALLOCNO_ASSIGNED_P (a)) |
| /* It can happen if A is not referenced but partially anticipated |
| somewhere in a region. */ |
| ALLOCNO_ASSIGNED_P (a) = true; |
| ira_free_allocno_updated_costs (a); |
| hard_regno = ALLOCNO_HARD_REGNO (a); |
| regno = ALLOCNO_REGNO (a); |
| reg_renumber[regno] = (hard_regno < 0 ? -1 : hard_regno); |
| if (hard_regno >= 0) |
| { |
| int i, nwords; |
| enum reg_class pclass; |
| ira_object_t obj; |
| |
| pclass = ira_pressure_class_translate[REGNO_REG_CLASS (hard_regno)]; |
| nwords = ALLOCNO_NUM_OBJECTS (a); |
| for (i = 0; i < nwords; i++) |
| { |
| obj = ALLOCNO_OBJECT (a, i); |
| IOR_COMPL_HARD_REG_SET (OBJECT_TOTAL_CONFLICT_HARD_REGS (obj), |
| reg_class_contents[pclass]); |
| } |
| if (ALLOCNO_CALLS_CROSSED_NUM (a) != 0 |
| && ira_hard_reg_set_intersection_p (hard_regno, ALLOCNO_MODE (a), |
| call_used_reg_set)) |
| { |
| ira_assert (!optimize || flag_caller_saves |
| || (ALLOCNO_CALLS_CROSSED_NUM (a) |
| == ALLOCNO_CHEAP_CALLS_CROSSED_NUM (a)) |
| || regno >= ira_reg_equiv_len |
| || ira_equiv_no_lvalue_p (regno)); |
| caller_save_needed = 1; |
| } |
| } |
| } |
| } |
| |
| /* Set up allocno assignment flags for further allocation |
| improvements. */ |
| static void |
| setup_allocno_assignment_flags (void) |
| { |
| int hard_regno; |
| ira_allocno_t a; |
| ira_allocno_iterator ai; |
| |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| if (! ALLOCNO_ASSIGNED_P (a)) |
| /* It can happen if A is not referenced but partially anticipated |
| somewhere in a region. */ |
| ira_free_allocno_updated_costs (a); |
| hard_regno = ALLOCNO_HARD_REGNO (a); |
| /* Don't assign hard registers to allocnos which are destination |
| of removed store at the end of loop. It has no sense to keep |
| the same value in different hard registers. It is also |
| impossible to assign hard registers correctly to such |
| allocnos because the cost info and info about intersected |
| calls are incorrect for them. */ |
| ALLOCNO_ASSIGNED_P (a) = (hard_regno >= 0 |
| || ALLOCNO_EMIT_DATA (a)->mem_optimized_dest_p |
| || (ALLOCNO_MEMORY_COST (a) |
| - ALLOCNO_CLASS_COST (a)) < 0); |
| ira_assert |
| (hard_regno < 0 |
| || ira_hard_reg_in_set_p (hard_regno, ALLOCNO_MODE (a), |
| reg_class_contents[ALLOCNO_CLASS (a)])); |
| } |
| } |
| |
| /* Evaluate overall allocation cost and the costs for using hard |
| registers and memory for allocnos. */ |
| static void |
| calculate_allocation_cost (void) |
| { |
| int hard_regno, cost; |
| ira_allocno_t a; |
| ira_allocno_iterator ai; |
| |
| ira_overall_cost = ira_reg_cost = ira_mem_cost = 0; |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| hard_regno = ALLOCNO_HARD_REGNO (a); |
| ira_assert (hard_regno < 0 |
| || (ira_hard_reg_in_set_p |
| (hard_regno, ALLOCNO_MODE (a), |
| reg_class_contents[ALLOCNO_CLASS (a)]))); |
| if (hard_regno < 0) |
| { |
| cost = ALLOCNO_MEMORY_COST (a); |
| ira_mem_cost += cost; |
| } |
| else if (ALLOCNO_HARD_REG_COSTS (a) != NULL) |
| { |
| cost = (ALLOCNO_HARD_REG_COSTS (a) |
| [ira_class_hard_reg_index |
| [ALLOCNO_CLASS (a)][hard_regno]]); |
| ira_reg_cost += cost; |
| } |
| else |
| { |
| cost = ALLOCNO_CLASS_COST (a); |
| ira_reg_cost += cost; |
| } |
| ira_overall_cost += cost; |
| } |
| |
| if (internal_flag_ira_verbose > 0 && ira_dump_file != NULL) |
| { |
| fprintf (ira_dump_file, |
| "+++Costs: overall %d, reg %d, mem %d, ld %d, st %d, move %d\n", |
| ira_overall_cost, ira_reg_cost, ira_mem_cost, |
| ira_load_cost, ira_store_cost, ira_shuffle_cost); |
| fprintf (ira_dump_file, "+++ move loops %d, new jumps %d\n", |
| ira_move_loops_num, ira_additional_jumps_num); |
| } |
| |
| } |
| |
| #ifdef ENABLE_IRA_CHECKING |
| /* Check the correctness of the allocation. We do need this because |
| of complicated code to transform more one region internal |
| representation into one region representation. */ |
| static void |
| check_allocation (void) |
| { |
| ira_allocno_t a; |
| int hard_regno, nregs, conflict_nregs; |
| ira_allocno_iterator ai; |
| |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| int n = ALLOCNO_NUM_OBJECTS (a); |
| int i; |
| |
| if (ALLOCNO_CAP_MEMBER (a) != NULL |
| || (hard_regno = ALLOCNO_HARD_REGNO (a)) < 0) |
| continue; |
| nregs = hard_regno_nregs[hard_regno][ALLOCNO_MODE (a)]; |
| if (nregs == 1) |
| /* We allocated a single hard register. */ |
| n = 1; |
| else if (n > 1) |
| /* We allocated multiple hard registers, and we will test |
| conflicts in a granularity of single hard regs. */ |
| nregs = 1; |
| |
| for (i = 0; i < n; i++) |
| { |
| ira_object_t obj = ALLOCNO_OBJECT (a, i); |
| ira_object_t conflict_obj; |
| ira_object_conflict_iterator oci; |
| int this_regno = hard_regno; |
| if (n > 1) |
| { |
| if (REG_WORDS_BIG_ENDIAN) |
| this_regno += n - i - 1; |
| else |
| this_regno += i; |
| } |
| FOR_EACH_OBJECT_CONFLICT (obj, conflict_obj, oci) |
| { |
| ira_allocno_t conflict_a = OBJECT_ALLOCNO (conflict_obj); |
| int conflict_hard_regno = ALLOCNO_HARD_REGNO (conflict_a); |
| if (conflict_hard_regno < 0) |
| continue; |
| |
| conflict_nregs |
| = (hard_regno_nregs |
| [conflict_hard_regno][ALLOCNO_MODE (conflict_a)]); |
| |
| if (ALLOCNO_NUM_OBJECTS (conflict_a) > 1 |
| && conflict_nregs == ALLOCNO_NUM_OBJECTS (conflict_a)) |
| { |
| if (REG_WORDS_BIG_ENDIAN) |
| conflict_hard_regno += (ALLOCNO_NUM_OBJECTS (conflict_a) |
| - OBJECT_SUBWORD (conflict_obj) - 1); |
| else |
| conflict_hard_regno += OBJECT_SUBWORD (conflict_obj); |
| conflict_nregs = 1; |
| } |
| |
| if ((conflict_hard_regno <= this_regno |
| && this_regno < conflict_hard_regno + conflict_nregs) |
| || (this_regno <= conflict_hard_regno |
| && conflict_hard_regno < this_regno + nregs)) |
| { |
| fprintf (stderr, "bad allocation for %d and %d\n", |
| ALLOCNO_REGNO (a), ALLOCNO_REGNO (conflict_a)); |
| gcc_unreachable (); |
| } |
| } |
| } |
| } |
| } |
| #endif |
| |
| /* Allocate REG_EQUIV_INIT. Set up it from IRA_REG_EQUIV which should |
| be already calculated. */ |
| static void |
| setup_reg_equiv_init (void) |
| { |
| int i; |
| int max_regno = max_reg_num (); |
| |
| for (i = 0; i < max_regno; i++) |
| reg_equiv_init (i) = ira_reg_equiv[i].init_insns; |
| } |
| |
| /* Update equiv regno from movement of FROM_REGNO to TO_REGNO. INSNS |
| are insns which were generated for such movement. It is assumed |
| that FROM_REGNO and TO_REGNO always have the same value at the |
| point of any move containing such registers. This function is used |
| to update equiv info for register shuffles on the region borders |
| and for caller save/restore insns. */ |
| void |
| ira_update_equiv_info_by_shuffle_insn (int to_regno, int from_regno, rtx insns) |
| { |
| rtx insn, x, note; |
| |
| if (! ira_reg_equiv[from_regno].defined_p |
| && (! ira_reg_equiv[to_regno].defined_p |
| || ((x = ira_reg_equiv[to_regno].memory) != NULL_RTX |
| && ! MEM_READONLY_P (x)))) |
| return; |
| insn = insns; |
| if (NEXT_INSN (insn) != NULL_RTX) |
| { |
| if (! ira_reg_equiv[to_regno].defined_p) |
| { |
| ira_assert (ira_reg_equiv[to_regno].init_insns == NULL_RTX); |
| return; |
| } |
| ira_reg_equiv[to_regno].defined_p = false; |
| ira_reg_equiv[to_regno].memory |
| = ira_reg_equiv[to_regno].constant |
| = ira_reg_equiv[to_regno].invariant |
| = ira_reg_equiv[to_regno].init_insns = NULL_RTX; |
| if (internal_flag_ira_verbose > 3 && ira_dump_file != NULL) |
| fprintf (ira_dump_file, |
| " Invalidating equiv info for reg %d\n", to_regno); |
| return; |
| } |
| /* It is possible that FROM_REGNO still has no equivalence because |
| in shuffles to_regno<-from_regno and from_regno<-to_regno the 2nd |
| insn was not processed yet. */ |
| if (ira_reg_equiv[from_regno].defined_p) |
| { |
| ira_reg_equiv[to_regno].defined_p = true; |
| if ((x = ira_reg_equiv[from_regno].memory) != NULL_RTX) |
| { |
| ira_assert (ira_reg_equiv[from_regno].invariant == NULL_RTX |
| && ira_reg_equiv[from_regno].constant == NULL_RTX); |
| ira_assert (ira_reg_equiv[to_regno].memory == NULL_RTX |
| || rtx_equal_p (ira_reg_equiv[to_regno].memory, x)); |
| ira_reg_equiv[to_regno].memory = x; |
| if (! MEM_READONLY_P (x)) |
| /* We don't add the insn to insn init list because memory |
| equivalence is just to say what memory is better to use |
| when the pseudo is spilled. */ |
| return; |
| } |
| else if ((x = ira_reg_equiv[from_regno].constant) != NULL_RTX) |
| { |
| ira_assert (ira_reg_equiv[from_regno].invariant == NULL_RTX); |
| ira_assert (ira_reg_equiv[to_regno].constant == NULL_RTX |
| || rtx_equal_p (ira_reg_equiv[to_regno].constant, x)); |
| ira_reg_equiv[to_regno].constant = x; |
| } |
| else |
| { |
| x = ira_reg_equiv[from_regno].invariant; |
| ira_assert (x != NULL_RTX); |
| ira_assert (ira_reg_equiv[to_regno].invariant == NULL_RTX |
| || rtx_equal_p (ira_reg_equiv[to_regno].invariant, x)); |
| ira_reg_equiv[to_regno].invariant = x; |
| } |
| if (find_reg_note (insn, REG_EQUIV, x) == NULL_RTX) |
| { |
| note = set_unique_reg_note (insn, REG_EQUIV, x); |
| gcc_assert (note != NULL_RTX); |
| if (internal_flag_ira_verbose > 3 && ira_dump_file != NULL) |
| { |
| fprintf (ira_dump_file, |
| " Adding equiv note to insn %u for reg %d ", |
| INSN_UID (insn), to_regno); |
| dump_value_slim (ira_dump_file, x, 1); |
| fprintf (ira_dump_file, "\n"); |
| } |
| } |
| } |
| ira_reg_equiv[to_regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, insn, |
| ira_reg_equiv[to_regno].init_insns); |
| if (internal_flag_ira_verbose > 3 && ira_dump_file != NULL) |
| fprintf (ira_dump_file, |
| " Adding equiv init move insn %u to reg %d\n", |
| INSN_UID (insn), to_regno); |
| } |
| |
| /* Fix values of array REG_EQUIV_INIT after live range splitting done |
| by IRA. */ |
| static void |
| fix_reg_equiv_init (void) |
| { |
| int max_regno = max_reg_num (); |
| int i, new_regno, max; |
| rtx x, prev, next, insn, set; |
| |
| if (max_regno_before_ira < max_regno) |
| { |
| max = vec_safe_length (reg_equivs); |
| grow_reg_equivs (); |
| for (i = FIRST_PSEUDO_REGISTER; i < max; i++) |
| for (prev = NULL_RTX, x = reg_equiv_init (i); |
| x != NULL_RTX; |
| x = next) |
| { |
| next = XEXP (x, 1); |
| insn = XEXP (x, 0); |
| set = single_set (insn); |
| ira_assert (set != NULL_RTX |
| && (REG_P (SET_DEST (set)) || REG_P (SET_SRC (set)))); |
| if (REG_P (SET_DEST (set)) |
| && ((int) REGNO (SET_DEST (set)) == i |
| || (int) ORIGINAL_REGNO (SET_DEST (set)) == i)) |
| new_regno = REGNO (SET_DEST (set)); |
| else if (REG_P (SET_SRC (set)) |
| && ((int) REGNO (SET_SRC (set)) == i |
| || (int) ORIGINAL_REGNO (SET_SRC (set)) == i)) |
| new_regno = REGNO (SET_SRC (set)); |
| else |
| gcc_unreachable (); |
| if (new_regno == i) |
| prev = x; |
| else |
| { |
| /* Remove the wrong list element. */ |
| if (prev == NULL_RTX) |
| reg_equiv_init (i) = next; |
| else |
| XEXP (prev, 1) = next; |
| XEXP (x, 1) = reg_equiv_init (new_regno); |
| reg_equiv_init (new_regno) = x; |
| } |
| } |
| } |
| } |
| |
| #ifdef ENABLE_IRA_CHECKING |
| /* Print redundant memory-memory copies. */ |
| static void |
| print_redundant_copies (void) |
| { |
| int hard_regno; |
| ira_allocno_t a; |
| ira_copy_t cp, next_cp; |
| ira_allocno_iterator ai; |
| |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| if (ALLOCNO_CAP_MEMBER (a) != NULL) |
| /* It is a cap. */ |
| continue; |
| hard_regno = ALLOCNO_HARD_REGNO (a); |
| if (hard_regno >= 0) |
| continue; |
| for (cp = ALLOCNO_COPIES (a); cp != NULL; cp = next_cp) |
| if (cp->first == a) |
| next_cp = cp->next_first_allocno_copy; |
| else |
| { |
| next_cp = cp->next_second_allocno_copy; |
| if (internal_flag_ira_verbose > 4 && ira_dump_file != NULL |
| && cp->insn != NULL_RTX |
| && ALLOCNO_HARD_REGNO (cp->first) == hard_regno) |
| fprintf (ira_dump_file, |
| " Redundant move from %d(freq %d):%d\n", |
| INSN_UID (cp->insn), cp->freq, hard_regno); |
| } |
| } |
| } |
| #endif |
| |
| /* Setup preferred and alternative classes for new pseudo-registers |
| created by IRA starting with START. */ |
| static void |
| setup_preferred_alternate_classes_for_new_pseudos (int start) |
| { |
| int i, old_regno; |
| int max_regno = max_reg_num (); |
| |
| for (i = start; i < max_regno; i++) |
| { |
| old_regno = ORIGINAL_REGNO (regno_reg_rtx[i]); |
| ira_assert (i != old_regno); |
| setup_reg_classes (i, reg_preferred_class (old_regno), |
| reg_alternate_class (old_regno), |
| reg_allocno_class (old_regno)); |
| if (internal_flag_ira_verbose > 2 && ira_dump_file != NULL) |
| fprintf (ira_dump_file, |
| " New r%d: setting preferred %s, alternative %s\n", |
| i, reg_class_names[reg_preferred_class (old_regno)], |
| reg_class_names[reg_alternate_class (old_regno)]); |
| } |
| } |
| |
| |
| /* The number of entries allocated in teg_info. */ |
| static int allocated_reg_info_size; |
| |
| /* Regional allocation can create new pseudo-registers. This function |
| expands some arrays for pseudo-registers. */ |
| static void |
| expand_reg_info (void) |
| { |
| int i; |
| int size = max_reg_num (); |
| |
| resize_reg_info (); |
| for (i = allocated_reg_info_size; i < size; i++) |
| setup_reg_classes (i, GENERAL_REGS, ALL_REGS, GENERAL_REGS); |
| setup_preferred_alternate_classes_for_new_pseudos (allocated_reg_info_size); |
| allocated_reg_info_size = size; |
| } |
| |
| /* Return TRUE if there is too high register pressure in the function. |
| It is used to decide when stack slot sharing is worth to do. */ |
| static bool |
| too_high_register_pressure_p (void) |
| { |
| int i; |
| enum reg_class pclass; |
| |
| for (i = 0; i < ira_pressure_classes_num; i++) |
| { |
| pclass = ira_pressure_classes[i]; |
| if (ira_loop_tree_root->reg_pressure[pclass] > 10000) |
| return true; |
| } |
| return false; |
| } |
| |
| |
| |
| /* Indicate that hard register number FROM was eliminated and replaced with |
| an offset from hard register number TO. The status of hard registers live |
| at the start of a basic block is updated by replacing a use of FROM with |
| a use of TO. */ |
| |
| void |
| mark_elimination (int from, int to) |
| { |
| basic_block bb; |
| bitmap r; |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| r = DF_LR_IN (bb); |
| if (bitmap_bit_p (r, from)) |
| { |
| bitmap_clear_bit (r, from); |
| bitmap_set_bit (r, to); |
| } |
| if (! df_live) |
| continue; |
| r = DF_LIVE_IN (bb); |
| if (bitmap_bit_p (r, from)) |
| { |
| bitmap_clear_bit (r, from); |
| bitmap_set_bit (r, to); |
| } |
| } |
| } |
| |
| |
| |
| /* The length of the following array. */ |
| int ira_reg_equiv_len; |
| |
| /* Info about equiv. info for each register. */ |
| struct ira_reg_equiv_s *ira_reg_equiv; |
| |
| /* Expand ira_reg_equiv if necessary. */ |
| void |
| ira_expand_reg_equiv (void) |
| { |
| int old = ira_reg_equiv_len; |
| |
| if (ira_reg_equiv_len > max_reg_num ()) |
| return; |
| ira_reg_equiv_len = max_reg_num () * 3 / 2 + 1; |
| ira_reg_equiv |
| = (struct ira_reg_equiv_s *) xrealloc (ira_reg_equiv, |
| ira_reg_equiv_len |
| * sizeof (struct ira_reg_equiv_s)); |
| gcc_assert (old < ira_reg_equiv_len); |
| memset (ira_reg_equiv + old, 0, |
| sizeof (struct ira_reg_equiv_s) * (ira_reg_equiv_len - old)); |
| } |
| |
| static void |
| init_reg_equiv (void) |
| { |
| ira_reg_equiv_len = 0; |
| ira_reg_equiv = NULL; |
| ira_expand_reg_equiv (); |
| } |
| |
| static void |
| finish_reg_equiv (void) |
| { |
| free (ira_reg_equiv); |
| } |
| |
| |
| |
| struct equivalence |
| { |
| /* Set when a REG_EQUIV note is found or created. Use to |
| keep track of what memory accesses might be created later, |
| e.g. by reload. */ |
| rtx replacement; |
| rtx *src_p; |
| /* The list of each instruction which initializes this register. */ |
| rtx init_insns; |
| /* Loop depth is used to recognize equivalences which appear |
| to be present within the same loop (or in an inner loop). */ |
| int loop_depth; |
| /* Nonzero if this had a preexisting REG_EQUIV note. */ |
| int is_arg_equivalence; |
| /* Set when an attempt should be made to replace a register |
| with the associated src_p entry. */ |
| char replace; |
| }; |
| |
| /* reg_equiv[N] (where N is a pseudo reg number) is the equivalence |
| structure for that register. */ |
| static struct equivalence *reg_equiv; |
| |
| /* Used for communication between the following two functions: contains |
| a MEM that we wish to ensure remains unchanged. */ |
| static rtx equiv_mem; |
| |
| /* Set nonzero if EQUIV_MEM is modified. */ |
| static int equiv_mem_modified; |
| |
| /* If EQUIV_MEM is modified by modifying DEST, indicate that it is modified. |
| Called via note_stores. */ |
| static void |
| validate_equiv_mem_from_store (rtx dest, const_rtx set ATTRIBUTE_UNUSED, |
| void *data ATTRIBUTE_UNUSED) |
| { |
| if ((REG_P (dest) |
| && reg_overlap_mentioned_p (dest, equiv_mem)) |
| || (MEM_P (dest) |
| && anti_dependence (equiv_mem, dest))) |
| equiv_mem_modified = 1; |
| } |
| |
| /* Verify that no store between START and the death of REG invalidates |
| MEMREF. MEMREF is invalidated by modifying a register used in MEMREF, |
| by storing into an overlapping memory location, or with a non-const |
| CALL_INSN. |
| |
| Return 1 if MEMREF remains valid. */ |
| static int |
| validate_equiv_mem (rtx start, rtx reg, rtx memref) |
| { |
| rtx insn; |
| rtx note; |
| |
| equiv_mem = memref; |
| equiv_mem_modified = 0; |
| |
| /* If the memory reference has side effects or is volatile, it isn't a |
| valid equivalence. */ |
| if (side_effects_p (memref)) |
| return 0; |
| |
| for (insn = start; insn && ! equiv_mem_modified; insn = NEXT_INSN (insn)) |
| { |
| if (! INSN_P (insn)) |
| continue; |
| |
| if (find_reg_note (insn, REG_DEAD, reg)) |
| return 1; |
| |
| /* This used to ignore readonly memory and const/pure calls. The problem |
| is the equivalent form may reference a pseudo which gets assigned a |
| call clobbered hard reg. When we later replace REG with its |
| equivalent form, the value in the call-clobbered reg has been |
| changed and all hell breaks loose. */ |
| if (CALL_P (insn)) |
| return 0; |
| |
| note_stores (PATTERN (insn), validate_equiv_mem_from_store, NULL); |
| |
| /* If a register mentioned in MEMREF is modified via an |
| auto-increment, we lose the equivalence. Do the same if one |
| dies; although we could extend the life, it doesn't seem worth |
| the trouble. */ |
| |
| for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) |
| if ((REG_NOTE_KIND (note) == REG_INC |
| || REG_NOTE_KIND (note) == REG_DEAD) |
| && REG_P (XEXP (note, 0)) |
| && reg_overlap_mentioned_p (XEXP (note, 0), memref)) |
| return 0; |
| } |
| |
| return 0; |
| } |
| |
| /* Returns zero if X is known to be invariant. */ |
| static int |
| equiv_init_varies_p (rtx x) |
| { |
| RTX_CODE code = GET_CODE (x); |
| int i; |
| const char *fmt; |
| |
| switch (code) |
| { |
| case MEM: |
| return !MEM_READONLY_P (x) || equiv_init_varies_p (XEXP (x, 0)); |
| |
| case CONST: |
| CASE_CONST_ANY: |
| case SYMBOL_REF: |
| case LABEL_REF: |
| return 0; |
| |
| case REG: |
| return reg_equiv[REGNO (x)].replace == 0 && rtx_varies_p (x, 0); |
| |
| case ASM_OPERANDS: |
| if (MEM_VOLATILE_P (x)) |
| return 1; |
| |
| /* Fall through. */ |
| |
| default: |
| break; |
| } |
| |
| fmt = GET_RTX_FORMAT (code); |
| for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| if (fmt[i] == 'e') |
| { |
| if (equiv_init_varies_p (XEXP (x, i))) |
| return 1; |
| } |
| else if (fmt[i] == 'E') |
| { |
| int j; |
| for (j = 0; j < XVECLEN (x, i); j++) |
| if (equiv_init_varies_p (XVECEXP (x, i, j))) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| /* Returns nonzero if X (used to initialize register REGNO) is movable. |
| X is only movable if the registers it uses have equivalent initializations |
| which appear to be within the same loop (or in an inner loop) and movable |
| or if they are not candidates for local_alloc and don't vary. */ |
| static int |
| equiv_init_movable_p (rtx x, int regno) |
| { |
| int i, j; |
| const char *fmt; |
| enum rtx_code code = GET_CODE (x); |
| |
| switch (code) |
| { |
| case SET: |
| return equiv_init_movable_p (SET_SRC (x), regno); |
| |
| case CC0: |
| case CLOBBER: |
| return 0; |
| |
| case PRE_INC: |
| case PRE_DEC: |
| case POST_INC: |
| case POST_DEC: |
| case PRE_MODIFY: |
| case POST_MODIFY: |
| return 0; |
| |
| case REG: |
| return ((reg_equiv[REGNO (x)].loop_depth >= reg_equiv[regno].loop_depth |
| && reg_equiv[REGNO (x)].replace) |
| || (REG_BASIC_BLOCK (REGNO (x)) < NUM_FIXED_BLOCKS |
| && ! rtx_varies_p (x, 0))); |
| |
| case UNSPEC_VOLATILE: |
| return 0; |
| |
| case ASM_OPERANDS: |
| if (MEM_VOLATILE_P (x)) |
| return 0; |
| |
| /* Fall through. */ |
| |
| default: |
| break; |
| } |
| |
| fmt = GET_RTX_FORMAT (code); |
| for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| switch (fmt[i]) |
| { |
| case 'e': |
| if (! equiv_init_movable_p (XEXP (x, i), regno)) |
| return 0; |
| break; |
| case 'E': |
| for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| if (! equiv_init_movable_p (XVECEXP (x, i, j), regno)) |
| return 0; |
| break; |
| } |
| |
| return 1; |
| } |
| |
| /* TRUE if X uses any registers for which reg_equiv[REGNO].replace is |
| true. */ |
| static int |
| contains_replace_regs (rtx x) |
| { |
| int i, j; |
| const char *fmt; |
| enum rtx_code code = GET_CODE (x); |
| |
| switch (code) |
| { |
| case CONST: |
| case LABEL_REF: |
| case SYMBOL_REF: |
| CASE_CONST_ANY: |
| case PC: |
| case CC0: |
| case HIGH: |
| return 0; |
| |
| case REG: |
| return reg_equiv[REGNO (x)].replace; |
| |
| default: |
| break; |
| } |
| |
| fmt = GET_RTX_FORMAT (code); |
| for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| switch (fmt[i]) |
| { |
| case 'e': |
| if (contains_replace_regs (XEXP (x, i))) |
| return 1; |
| break; |
| case 'E': |
| for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| if (contains_replace_regs (XVECEXP (x, i, j))) |
| return 1; |
| break; |
| } |
| |
| return 0; |
| } |
| |
| /* TRUE if X references a memory location that would be affected by a store |
| to MEMREF. */ |
| static int |
| memref_referenced_p (rtx memref, rtx x) |
| { |
| int i, j; |
| const char *fmt; |
| enum rtx_code code = GET_CODE (x); |
| |
| switch (code) |
| { |
| case CONST: |
| case LABEL_REF: |
| case SYMBOL_REF: |
| CASE_CONST_ANY: |
| case PC: |
| case CC0: |
| case HIGH: |
| case LO_SUM: |
| return 0; |
| |
| case REG: |
| return (reg_equiv[REGNO (x)].replacement |
| && memref_referenced_p (memref, |
| reg_equiv[REGNO (x)].replacement)); |
| |
| case MEM: |
| if (true_dependence (memref, VOIDmode, x)) |
| return 1; |
| break; |
| |
| case SET: |
| /* If we are setting a MEM, it doesn't count (its address does), but any |
| other SET_DEST that has a MEM in it is referencing the MEM. */ |
| if (MEM_P (SET_DEST (x))) |
| { |
| if (memref_referenced_p (memref, XEXP (SET_DEST (x), 0))) |
| return 1; |
| } |
| else if (memref_referenced_p (memref, SET_DEST (x))) |
| return 1; |
| |
| return memref_referenced_p (memref, SET_SRC (x)); |
| |
| default: |
| break; |
| } |
| |
| fmt = GET_RTX_FORMAT (code); |
| for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| switch (fmt[i]) |
| { |
| case 'e': |
| if (memref_referenced_p (memref, XEXP (x, i))) |
| return 1; |
| break; |
| case 'E': |
| for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| if (memref_referenced_p (memref, XVECEXP (x, i, j))) |
| return 1; |
| break; |
| } |
| |
| return 0; |
| } |
| |
| /* TRUE if some insn in the range (START, END] references a memory location |
| that would be affected by a store to MEMREF. */ |
| static int |
| memref_used_between_p (rtx memref, rtx start, rtx end) |
| { |
| rtx insn; |
| |
| for (insn = NEXT_INSN (start); insn != NEXT_INSN (end); |
| insn = NEXT_INSN (insn)) |
| { |
| if (!NONDEBUG_INSN_P (insn)) |
| continue; |
| |
| if (memref_referenced_p (memref, PATTERN (insn))) |
| return 1; |
| |
| /* Nonconst functions may access memory. */ |
| if (CALL_P (insn) && (! RTL_CONST_CALL_P (insn))) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| /* Mark REG as having no known equivalence. |
| Some instructions might have been processed before and furnished |
| with REG_EQUIV notes for this register; these notes will have to be |
| removed. |
| STORE is the piece of RTL that does the non-constant / conflicting |
| assignment - a SET, CLOBBER or REG_INC note. It is currently not used, |
| but needs to be there because this function is called from note_stores. */ |
| static void |
| no_equiv (rtx reg, const_rtx store ATTRIBUTE_UNUSED, |
| void *data ATTRIBUTE_UNUSED) |
| { |
| int regno; |
| rtx list; |
| |
| if (!REG_P (reg)) |
| return; |
| regno = REGNO (reg); |
| list = reg_equiv[regno].init_insns; |
| if (list == const0_rtx) |
| return; |
| reg_equiv[regno].init_insns = const0_rtx; |
| reg_equiv[regno].replacement = NULL_RTX; |
| /* This doesn't matter for equivalences made for argument registers, we |
| should keep their initialization insns. */ |
| if (reg_equiv[regno].is_arg_equivalence) |
| return; |
| ira_reg_equiv[regno].defined_p = false; |
| ira_reg_equiv[regno].init_insns = NULL_RTX; |
| for (; list; list = XEXP (list, 1)) |
| { |
| rtx insn = XEXP (list, 0); |
| remove_note (insn, find_reg_note (insn, REG_EQUIV, NULL_RTX)); |
| } |
| } |
| |
| /* Check whether the SUBREG is a paradoxical subreg and set the result |
| in PDX_SUBREGS. */ |
| |
| static int |
| set_paradoxical_subreg (rtx *subreg, void *pdx_subregs) |
| { |
| rtx reg; |
| |
| if ((*subreg) == NULL_RTX) |
| return 1; |
| if (GET_CODE (*subreg) != SUBREG) |
| return 0; |
| reg = SUBREG_REG (*subreg); |
| if (!REG_P (reg)) |
| return 0; |
| |
| if (paradoxical_subreg_p (*subreg)) |
| ((bool *)pdx_subregs)[REGNO (reg)] = true; |
| |
| return 0; |
| } |
| |
| /* In DEBUG_INSN location adjust REGs from CLEARED_REGS bitmap to the |
| equivalent replacement. */ |
| |
| static rtx |
| adjust_cleared_regs (rtx loc, const_rtx old_rtx ATTRIBUTE_UNUSED, void *data) |
| { |
| if (REG_P (loc)) |
| { |
| bitmap cleared_regs = (bitmap) data; |
| if (bitmap_bit_p (cleared_regs, REGNO (loc))) |
| return simplify_replace_fn_rtx (copy_rtx (*reg_equiv[REGNO (loc)].src_p), |
| NULL_RTX, adjust_cleared_regs, data); |
| } |
| return NULL_RTX; |
| } |
| |
| /* Nonzero if we recorded an equivalence for a LABEL_REF. */ |
| static int recorded_label_ref; |
| |
| /* Find registers that are equivalent to a single value throughout the |
| compilation (either because they can be referenced in memory or are |
| set once from a single constant). Lower their priority for a |
| register. |
| |
| If such a register is only referenced once, try substituting its |
| value into the using insn. If it succeeds, we can eliminate the |
| register completely. |
| |
| Initialize init_insns in ira_reg_equiv array. |
| |
| Return non-zero if jump label rebuilding should be done. */ |
| static int |
| update_equiv_regs (void) |
| { |
| rtx insn; |
| basic_block bb; |
| int loop_depth; |
| bitmap cleared_regs; |
| bool *pdx_subregs; |
| |
| /* We need to keep track of whether or not we recorded a LABEL_REF so |
| that we know if the jump optimizer needs to be rerun. */ |
| recorded_label_ref = 0; |
| |
| /* Use pdx_subregs to show whether a reg is used in a paradoxical |
| subreg. */ |
| pdx_subregs = XCNEWVEC (bool, max_regno); |
| |
| reg_equiv = XCNEWVEC (struct equivalence, max_regno); |
| grow_reg_equivs (); |
| |
| init_alias_analysis (); |
| |
| /* Scan insns and set pdx_subregs[regno] if the reg is used in a |
| paradoxical subreg. Don't set such reg sequivalent to a mem, |
| because lra will not substitute such equiv memory in order to |
| prevent access beyond allocated memory for paradoxical memory subreg. */ |
| FOR_EACH_BB_FN (bb, cfun) |
| FOR_BB_INSNS (bb, insn) |
| if (NONDEBUG_INSN_P (insn)) |
| for_each_rtx (&insn, set_paradoxical_subreg, (void *) pdx_subregs); |
| |
| /* Scan the insns and find which registers have equivalences. Do this |
| in a separate scan of the insns because (due to -fcse-follow-jumps) |
| a register can be set below its use. */ |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| loop_depth = bb_loop_depth (bb); |
| |
| for (insn = BB_HEAD (bb); |
| insn != NEXT_INSN (BB_END (bb)); |
| insn = NEXT_INSN (insn)) |
| { |
| rtx note; |
| rtx set; |
| rtx dest, src; |
| int regno; |
| |
| if (! INSN_P (insn)) |
| continue; |
| |
| for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) |
| if (REG_NOTE_KIND (note) == REG_INC) |
| no_equiv (XEXP (note, 0), note, NULL); |
| |
| set = single_set (insn); |
| |
| /* If this insn contains more (or less) than a single SET, |
| only mark all destinations as having no known equivalence. */ |
| if (set == 0) |
| { |
| note_stores (PATTERN (insn), no_equiv, NULL); |
| continue; |
| } |
| else if (GET_CODE (PATTERN (insn)) == PARALLEL) |
| { |
| int i; |
| |
| for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) |
| { |
| rtx part = XVECEXP (PATTERN (insn), 0, i); |
| if (part != set) |
| note_stores (part, no_equiv, NULL); |
| } |
| } |
| |
| dest = SET_DEST (set); |
| src = SET_SRC (set); |
| |
| /* See if this is setting up the equivalence between an argument |
| register and its stack slot. */ |
| note = find_reg_note (insn, REG_EQUIV, NULL_RTX); |
| if (note) |
| { |
| gcc_assert (REG_P (dest)); |
| regno = REGNO (dest); |
| |
| /* Note that we don't want to clear init_insns in |
| ira_reg_equiv even if there are multiple sets of this |
| register. */ |
| reg_equiv[regno].is_arg_equivalence = 1; |
| |
| /* The insn result can have equivalence memory although |
| the equivalence is not set up by the insn. We add |
| this insn to init insns as it is a flag for now that |
| regno has an equivalence. We will remove the insn |
| from init insn list later. */ |
| if (rtx_equal_p (src, XEXP (note, 0)) || MEM_P (XEXP (note, 0))) |
| ira_reg_equiv[regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, insn, |
| ira_reg_equiv[regno].init_insns); |
| |
| /* Continue normally in case this is a candidate for |
| replacements. */ |
| } |
| |
| if (!optimize) |
| continue; |
| |
| /* We only handle the case of a pseudo register being set |
| once, or always to the same value. */ |
| /* ??? The mn10200 port breaks if we add equivalences for |
| values that need an ADDRESS_REGS register and set them equivalent |
| to a MEM of a pseudo. The actual problem is in the over-conservative |
| handling of INPADDR_ADDRESS / INPUT_ADDRESS / INPUT triples in |
| calculate_needs, but we traditionally work around this problem |
| here by rejecting equivalences when the destination is in a register |
| that's likely spilled. This is fragile, of course, since the |
| preferred class of a pseudo depends on all instructions that set |
| or use it. */ |
| |
| if (!REG_P (dest) |
| || (regno = REGNO (dest)) < FIRST_PSEUDO_REGISTER |
| || reg_equiv[regno].init_insns == const0_rtx |
| || (targetm.class_likely_spilled_p (reg_preferred_class (regno)) |
| && MEM_P (src) && ! reg_equiv[regno].is_arg_equivalence)) |
| { |
| /* This might be setting a SUBREG of a pseudo, a pseudo that is |
| also set somewhere else to a constant. */ |
| note_stores (set, no_equiv, NULL); |
| continue; |
| } |
| |
| /* Don't set reg (if pdx_subregs[regno] == true) equivalent to a mem. */ |
| if (MEM_P (src) && pdx_subregs[regno]) |
| { |
| note_stores (set, no_equiv, NULL); |
| continue; |
| } |
| |
| note = find_reg_note (insn, REG_EQUAL, NULL_RTX); |
| |
| /* cse sometimes generates function invariants, but doesn't put a |
| REG_EQUAL note on the insn. Since this note would be redundant, |
| there's no point creating it earlier than here. */ |
| if (! note && ! rtx_varies_p (src, 0)) |
| note = set_unique_reg_note (insn, REG_EQUAL, copy_rtx (src)); |
| |
| /* Don't bother considering a REG_EQUAL note containing an EXPR_LIST |
| since it represents a function call */ |
| if (note && GET_CODE (XEXP (note, 0)) == EXPR_LIST) |
| note = NULL_RTX; |
| |
| if (DF_REG_DEF_COUNT (regno) != 1 |
| && (! note |
| || rtx_varies_p (XEXP (note, 0), 0) |
| || (reg_equiv[regno].replacement |
| && ! rtx_equal_p (XEXP (note, 0), |
| reg_equiv[regno].replacement)))) |
| { |
| no_equiv (dest, set, NULL); |
| continue; |
| } |
| /* Record this insn as initializing this register. */ |
| reg_equiv[regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, insn, reg_equiv[regno].init_insns); |
| |
| /* If this register is known to be equal to a constant, record that |
| it is always equivalent to the constant. */ |
| if (DF_REG_DEF_COUNT (regno) == 1 |
| && note && ! rtx_varies_p (XEXP (note, 0), 0)) |
| { |
| rtx note_value = XEXP (note, 0); |
| remove_note (insn, note); |
| set_unique_reg_note (insn, REG_EQUIV, note_value); |
| } |
| |
| /* If this insn introduces a "constant" register, decrease the priority |
| of that register. Record this insn if the register is only used once |
| more and the equivalence value is the same as our source. |
| |
| The latter condition is checked for two reasons: First, it is an |
| indication that it may be more efficient to actually emit the insn |
| as written (if no registers are available, reload will substitute |
| the equivalence). Secondly, it avoids problems with any registers |
| dying in this insn whose death notes would be missed. |
| |
| If we don't have a REG_EQUIV note, see if this insn is loading |
| a register used only in one basic block from a MEM. If so, and the |
| MEM remains unchanged for the life of the register, add a REG_EQUIV |
| note. */ |
| |
| note = find_reg_note (insn, REG_EQUIV, NULL_RTX); |
| |
| if (note == 0 && REG_BASIC_BLOCK (regno) >= NUM_FIXED_BLOCKS |
| && MEM_P (SET_SRC (set)) |
| && validate_equiv_mem (insn, dest, SET_SRC (set))) |
| note = set_unique_reg_note (insn, REG_EQUIV, copy_rtx (SET_SRC (set))); |
| |
| if (note) |
| { |
| int regno = REGNO (dest); |
| rtx x = XEXP (note, 0); |
| |
| /* If we haven't done so, record for reload that this is an |
| equivalencing insn. */ |
| if (!reg_equiv[regno].is_arg_equivalence) |
| ira_reg_equiv[regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, insn, |
| ira_reg_equiv[regno].init_insns); |
| |
| /* Record whether or not we created a REG_EQUIV note for a LABEL_REF. |
| We might end up substituting the LABEL_REF for uses of the |
| pseudo here or later. That kind of transformation may turn an |
| indirect jump into a direct jump, in which case we must rerun the |
| jump optimizer to ensure that the JUMP_LABEL fields are valid. */ |
| if (GET_CODE (x) == LABEL_REF |
| || (GET_CODE (x) == CONST |
| && GET_CODE (XEXP (x, 0)) == PLUS |
| && (GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF))) |
| recorded_label_ref = 1; |
| |
| reg_equiv[regno].replacement = x; |
| reg_equiv[regno].src_p = &SET_SRC (set); |
| reg_equiv[regno].loop_depth = loop_depth; |
| |
| /* Don't mess with things live during setjmp. */ |
| if (REG_LIVE_LENGTH (regno) >= 0 && optimize) |
| { |
| /* Note that the statement below does not affect the priority |
| in local-alloc! */ |
| REG_LIVE_LENGTH (regno) *= 2; |
| |
| /* If the register is referenced exactly twice, meaning it is |
| set once and used once, indicate that the reference may be |
| replaced by the equivalence we computed above. Do this |
| even if the register is only used in one block so that |
| dependencies can be handled where the last register is |
| used in a different block (i.e. HIGH / LO_SUM sequences) |
| and to reduce the number of registers alive across |
| calls. */ |
| |
| if (REG_N_REFS (regno) == 2 |
| && (rtx_equal_p (x, src) |
| || ! equiv_init_varies_p (src)) |
| && NONJUMP_INSN_P (insn) |
| && equiv_init_movable_p (PATTERN (insn), regno)) |
| reg_equiv[regno].replace = 1; |
| } |
| } |
| } |
| } |
| |
| if (!optimize) |
| goto out; |
| |
| /* A second pass, to gather additional equivalences with memory. This needs |
| to be done after we know which registers we are going to replace. */ |
| |
| for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
| { |
| rtx set, src, dest; |
| unsigned regno; |
| |
| if (! INSN_P (insn)) |
| continue; |
| |
| set = single_set (insn); |
| if (! set) |
| continue; |
| |
| dest = SET_DEST (set); |
| src = SET_SRC (set); |
| |
| /* If this sets a MEM to the contents of a REG that is only used |
| in a single basic block, see if the register is always equivalent |
| to that memory location and if moving the store from INSN to the |
| insn that set REG is safe. If so, put a REG_EQUIV note on the |
| initializing insn. |
| |
| Don't add a REG_EQUIV note if the insn already has one. The existing |
| REG_EQUIV is likely more useful than the one we are adding. |
| |
| If one of the regs in the address has reg_equiv[REGNO].replace set, |
| then we can't add this REG_EQUIV note. The reg_equiv[REGNO].replace |
| optimization may move the set of this register immediately before |
| insn, which puts it after reg_equiv[REGNO].init_insns, and hence |
| the mention in the REG_EQUIV note would be to an uninitialized |
| pseudo. */ |
| |
| if (MEM_P (dest) && REG_P (src) |
| && (regno = REGNO (src)) >= FIRST_PSEUDO_REGISTER |
| && REG_BASIC_BLOCK (regno) >= NUM_FIXED_BLOCKS |
| && DF_REG_DEF_COUNT (regno) == 1 |
| && reg_equiv[regno].init_insns != 0 |
| && reg_equiv[regno].init_insns != const0_rtx |
| && ! find_reg_note (XEXP (reg_equiv[regno].init_insns, 0), |
| REG_EQUIV, NULL_RTX) |
| && ! contains_replace_regs (XEXP (dest, 0)) |
| && ! pdx_subregs[regno]) |
| { |
| rtx init_insn = XEXP (reg_equiv[regno].init_insns, 0); |
| if (validate_equiv_mem (init_insn, src, dest) |
| && ! memref_used_between_p (dest, init_insn, insn) |
| /* Attaching a REG_EQUIV note will fail if INIT_INSN has |
| multiple sets. */ |
| && set_unique_reg_note (init_insn, REG_EQUIV, copy_rtx (dest))) |
| { |
| /* This insn makes the equivalence, not the one initializing |
| the register. */ |
| ira_reg_equiv[regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, insn, NULL_RTX); |
| df_notes_rescan (init_insn); |
| } |
| } |
| } |
| |
| cleared_regs = BITMAP_ALLOC (NULL); |
| /* Now scan all regs killed in an insn to see if any of them are |
| registers only used that once. If so, see if we can replace the |
| reference with the equivalent form. If we can, delete the |
| initializing reference and this register will go away. If we |
| can't replace the reference, and the initializing reference is |
| within the same loop (or in an inner loop), then move the register |
| initialization just before the use, so that they are in the same |
| basic block. */ |
| FOR_EACH_BB_REVERSE_FN (bb, cfun) |
| { |
| loop_depth = bb_loop_depth (bb); |
| for (insn = BB_END (bb); |
| insn != PREV_INSN (BB_HEAD (bb)); |
| insn = PREV_INSN (insn)) |
| { |
| rtx link; |
| |
| if (! INSN_P (insn)) |
| continue; |
| |
| /* Don't substitute into a non-local goto, this confuses CFG. */ |
| if (JUMP_P (insn) |
| && find_reg_note (insn, REG_NON_LOCAL_GOTO, NULL_RTX)) |
| continue; |
| |
| for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) |
| { |
| if (REG_NOTE_KIND (link) == REG_DEAD |
| /* Make sure this insn still refers to the register. */ |
| && reg_mentioned_p (XEXP (link, 0), PATTERN (insn))) |
| { |
| int regno = REGNO (XEXP (link, 0)); |
| rtx equiv_insn; |
| |
| if (! reg_equiv[regno].replace |
| || reg_equiv[regno].loop_depth < loop_depth |
| /* There is no sense to move insns if live range |
| shrinkage or register pressure-sensitive |
| scheduling were done because it will not |
| improve allocation but worsen insn schedule |
| with a big probability. */ |
| || flag_live_range_shrinkage |
| || (flag_sched_pressure && flag_schedule_insns)) |
| continue; |
| |
| /* reg_equiv[REGNO].replace gets set only when |
| REG_N_REFS[REGNO] is 2, i.e. the register is set |
| once and used once. (If it were only set, but |
| not used, flow would have deleted the setting |
| insns.) Hence there can only be one insn in |
| reg_equiv[REGNO].init_insns. */ |
| gcc_assert (reg_equiv[regno].init_insns |
| && !XEXP (reg_equiv[regno].init_insns, 1)); |
| equiv_insn = XEXP (reg_equiv[regno].init_insns, 0); |
| |
| /* We may not move instructions that can throw, since |
| that changes basic block boundaries and we are not |
| prepared to adjust the CFG to match. */ |
| if (can_throw_internal (equiv_insn)) |
| continue; |
| |
| if (asm_noperands (PATTERN (equiv_insn)) < 0 |
| && validate_replace_rtx (regno_reg_rtx[regno], |
| *(reg_equiv[regno].src_p), insn)) |
| { |
| rtx equiv_link; |
| rtx last_link; |
| rtx note; |
| |
| /* Find the last note. */ |
| for (last_link = link; XEXP (last_link, 1); |
| last_link = XEXP (last_link, 1)) |
| ; |
| |
| /* Append the REG_DEAD notes from equiv_insn. */ |
| equiv_link = REG_NOTES (equiv_insn); |
| while (equiv_link) |
| { |
| note = equiv_link; |
| equiv_link = XEXP (equiv_link, 1); |
| if (REG_NOTE_KIND (note) == REG_DEAD) |
| { |
| remove_note (equiv_insn, note); |
| XEXP (last_link, 1) = note; |
| XEXP (note, 1) = NULL_RTX; |
| last_link = note; |
| } |
| } |
| |
| remove_death (regno, insn); |
| SET_REG_N_REFS (regno, 0); |
| REG_FREQ (regno) = 0; |
| delete_insn (equiv_insn); |
| |
| reg_equiv[regno].init_insns |
| = XEXP (reg_equiv[regno].init_insns, 1); |
| |
| ira_reg_equiv[regno].init_insns = NULL_RTX; |
| bitmap_set_bit (cleared_regs, regno); |
| } |
| /* Move the initialization of the register to just before |
| INSN. Update the flow information. */ |
| else if (prev_nondebug_insn (insn) != equiv_insn) |
| { |
| rtx new_insn; |
| |
| new_insn = emit_insn_before (PATTERN (equiv_insn), insn); |
| REG_NOTES (new_insn) = REG_NOTES (equiv_insn); |
| REG_NOTES (equiv_insn) = 0; |
| /* Rescan it to process the notes. */ |
| df_insn_rescan (new_insn); |
| |
| /* Make sure this insn is recognized before |
| reload begins, otherwise |
| eliminate_regs_in_insn will die. */ |
| INSN_CODE (new_insn) = INSN_CODE (equiv_insn); |
| |
| delete_insn (equiv_insn); |
| |
| XEXP (reg_equiv[regno].init_insns, 0) = new_insn; |
| |
| REG_BASIC_BLOCK (regno) = bb->index; |
| REG_N_CALLS_CROSSED (regno) = 0; |
| REG_FREQ_CALLS_CROSSED (regno) = 0; |
| REG_N_THROWING_CALLS_CROSSED (regno) = 0; |
| REG_LIVE_LENGTH (regno) = 2; |
| |
| if (insn == BB_HEAD (bb)) |
| BB_HEAD (bb) = PREV_INSN (insn); |
| |
| ira_reg_equiv[regno].init_insns |
| = gen_rtx_INSN_LIST (VOIDmode, new_insn, NULL_RTX); |
| bitmap_set_bit (cleared_regs, regno); |
| } |
| } |
| } |
| } |
| } |
| |
| if (!bitmap_empty_p (cleared_regs)) |
| { |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| bitmap_and_compl_into (DF_LR_IN (bb), cleared_regs); |
| bitmap_and_compl_into (DF_LR_OUT (bb), cleared_regs); |
| if (! df_live) |
| continue; |
| bitmap_and_compl_into (DF_LIVE_IN (bb), cleared_regs); |
| bitmap_and_compl_into (DF_LIVE_OUT (bb), cleared_regs); |
| } |
| |
| /* Last pass - adjust debug insns referencing cleared regs. */ |
| if (MAY_HAVE_DEBUG_INSNS) |
| for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
| if (DEBUG_INSN_P (insn)) |
| { |
| rtx old_loc = INSN_VAR_LOCATION_LOC (insn); |
| INSN_VAR_LOCATION_LOC (insn) |
| = simplify_replace_fn_rtx (old_loc, NULL_RTX, |
| adjust_cleared_regs, |
| (void *) cleared_regs); |
| if (old_loc != INSN_VAR_LOCATION_LOC (insn)) |
| df_insn_rescan (insn); |
| } |
| } |
| |
| BITMAP_FREE (cleared_regs); |
| |
| out: |
| /* Clean up. */ |
| |
| end_alias_analysis (); |
| free (reg_equiv); |
| free (pdx_subregs); |
| return recorded_label_ref; |
| } |
| |
| |
| |
| /* Set up fields memory, constant, and invariant from init_insns in |
| the structures of array ira_reg_equiv. */ |
| static void |
| setup_reg_equiv (void) |
| { |
| int i; |
| rtx elem, prev_elem, next_elem, insn, set, x; |
| |
| for (i = FIRST_PSEUDO_REGISTER; i < ira_reg_equiv_len; i++) |
| for (prev_elem = NULL, elem = ira_reg_equiv[i].init_insns; |
| elem; |
| prev_elem = elem, elem = next_elem) |
| { |
| next_elem = XEXP (elem, 1); |
| insn = XEXP (elem, 0); |
| set = single_set (insn); |
| |
| /* Init insns can set up equivalence when the reg is a destination or |
| a source (in this case the destination is memory). */ |
| if (set != 0 && (REG_P (SET_DEST (set)) || REG_P (SET_SRC (set)))) |
| { |
| if ((x = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != NULL) |
| { |
| x = XEXP (x, 0); |
| if (REG_P (SET_DEST (set)) |
| && REGNO (SET_DEST (set)) == (unsigned int) i |
| && ! rtx_equal_p (SET_SRC (set), x) && MEM_P (x)) |
| { |
| /* This insn reporting the equivalence but |
| actually not setting it. Remove it from the |
| list. */ |
| if (prev_elem == NULL) |
| ira_reg_equiv[i].init_insns = next_elem; |
| else |
| XEXP (prev_elem, 1) = next_elem; |
| elem = prev_elem; |
| } |
| } |
| else if (REG_P (SET_DEST (set)) |
| && REGNO (SET_DEST (set)) == (unsigned int) i) |
| x = SET_SRC (set); |
| else |
| { |
| gcc_assert (REG_P (SET_SRC (set)) |
| && REGNO (SET_SRC (set)) == (unsigned int) i); |
| x = SET_DEST (set); |
| } |
| if (! function_invariant_p (x) |
| || ! flag_pic |
| /* A function invariant is often CONSTANT_P but may |
| include a register. We promise to only pass |
| CONSTANT_P objects to LEGITIMATE_PIC_OPERAND_P. */ |
| || (CONSTANT_P (x) && LEGITIMATE_PIC_OPERAND_P (x))) |
| { |
| /* It can happen that a REG_EQUIV note contains a MEM |
| that is not a legitimate memory operand. As later |
| stages of reload assume that all addresses found in |
| the lra_regno_equiv_* arrays were originally |
| legitimate, we ignore such REG_EQUIV notes. */ |
| if (memory_operand (x, VOIDmode)) |
| { |
| ira_reg_equiv[i].defined_p = true; |
| ira_reg_equiv[i].memory = x; |
| continue; |
| } |
| else if (function_invariant_p (x)) |
| { |
| enum machine_mode mode; |
| |
| mode = GET_MODE (SET_DEST (set)); |
| if (GET_CODE (x) == PLUS |
| || x == frame_pointer_rtx || x == arg_pointer_rtx) |
| /* This is PLUS of frame pointer and a constant, |
| or fp, or argp. */ |
| ira_reg_equiv[i].invariant = x; |
| else if (targetm.legitimate_constant_p (mode, x)) |
| ira_reg_equiv[i].constant = x; |
| else |
| { |
| ira_reg_equiv[i].memory = force_const_mem (mode, x); |
| if (ira_reg_equiv[i].memory == NULL_RTX) |
| { |
| ira_reg_equiv[i].defined_p = false; |
| ira_reg_equiv[i].init_insns = NULL_RTX; |
| break; |
| } |
| } |
| ira_reg_equiv[i].defined_p = true; |
| continue; |
| } |
| } |
| } |
| ira_reg_equiv[i].defined_p = false; |
| ira_reg_equiv[i].init_insns = NULL_RTX; |
| break; |
| } |
| } |
| |
| |
| |
| /* Print chain C to FILE. */ |
| static void |
| print_insn_chain (FILE *file, struct insn_chain *c) |
| { |
| fprintf (file, "insn=%d, ", INSN_UID (c->insn)); |
| bitmap_print (file, &c->live_throughout, "live_throughout: ", ", "); |
| bitmap_print (file, &c->dead_or_set, "dead_or_set: ", "\n"); |
| } |
| |
| |
| /* Print all reload_insn_chains to FILE. */ |
| static void |
| print_insn_chains (FILE *file) |
| { |
| struct insn_chain *c; |
| for (c = reload_insn_chain; c ; c = c->next) |
| print_insn_chain (file, c); |
| } |
| |
| /* Return true if pseudo REGNO should be added to set live_throughout |
| or dead_or_set of the insn chains for reload consideration. */ |
| static bool |
| pseudo_for_reload_consideration_p (int regno) |
| { |
| /* Consider spilled pseudos too for IRA because they still have a |
| chance to get hard-registers in the reload when IRA is used. */ |
| return (reg_renumber[regno] >= 0 || ira_conflicts_p); |
| } |
| |
| /* Init LIVE_SUBREGS[ALLOCNUM] and LIVE_SUBREGS_USED[ALLOCNUM] using |
| REG to the number of nregs, and INIT_VALUE to get the |
| initialization. ALLOCNUM need not be the regno of REG. */ |
| static void |
| init_live_subregs (bool init_value, sbitmap *live_subregs, |
| bitmap live_subregs_used, int allocnum, rtx reg) |
| { |
| unsigned int regno = REGNO (SUBREG_REG (reg)); |
| int size = GET_MODE_SIZE (GET_MODE (regno_reg_rtx[regno])); |
| |
| gcc_assert (size > 0); |
| |
| /* Been there, done that. */ |
| if (bitmap_bit_p (live_subregs_used, allocnum)) |
| return; |
| |
| /* Create a new one. */ |
| if (live_subregs[allocnum] == NULL) |
| live_subregs[allocnum] = sbitmap_alloc (size); |
| |
| /* If the entire reg was live before blasting into subregs, we need |
| to init all of the subregs to ones else init to 0. */ |
| if (init_value) |
| bitmap_ones (live_subregs[allocnum]); |
| else |
| bitmap_clear (live_subregs[allocnum]); |
| |
| bitmap_set_bit (live_subregs_used, allocnum); |
| } |
| |
| /* Walk the insns of the current function and build reload_insn_chain, |
| and record register life information. */ |
| static void |
| build_insn_chain (void) |
| { |
| unsigned int i; |
| struct insn_chain **p = &reload_insn_chain; |
| basic_block bb; |
| struct insn_chain *c = NULL; |
| struct insn_chain *next = NULL; |
| bitmap live_relevant_regs = BITMAP_ALLOC (NULL); |
| bitmap elim_regset = BITMAP_ALLOC (NULL); |
| /* live_subregs is a vector used to keep accurate information about |
| which hardregs are live in multiword pseudos. live_subregs and |
| live_subregs_used are indexed by pseudo number. The live_subreg |
| entry for a particular pseudo is only used if the corresponding |
| element is non zero in live_subregs_used. The sbitmap size of |
| live_subreg[allocno] is number of bytes that the pseudo can |
| occupy. */ |
| sbitmap *live_subregs = XCNEWVEC (sbitmap, max_regno); |
| bitmap live_subregs_used = BITMAP_ALLOC (NULL); |
| |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| if (TEST_HARD_REG_BIT (eliminable_regset, i)) |
| bitmap_set_bit (elim_regset, i); |
| FOR_EACH_BB_REVERSE_FN (bb, cfun) |
| { |
| bitmap_iterator bi; |
| rtx insn; |
| |
| CLEAR_REG_SET (live_relevant_regs); |
| bitmap_clear (live_subregs_used); |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_get_live_out (bb), 0, i, bi) |
| { |
| if (i >= FIRST_PSEUDO_REGISTER) |
| break; |
| bitmap_set_bit (live_relevant_regs, i); |
| } |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_get_live_out (bb), |
| FIRST_PSEUDO_REGISTER, i, bi) |
| { |
| if (pseudo_for_reload_consideration_p (i)) |
| bitmap_set_bit (live_relevant_regs, i); |
| } |
| |
| FOR_BB_INSNS_REVERSE (bb, insn) |
| { |
| if (!NOTE_P (insn) && !BARRIER_P (insn)) |
| { |
| unsigned int uid = INSN_UID (insn); |
| df_ref *def_rec; |
| df_ref *use_rec; |
| |
| c = new_insn_chain (); |
| c->next = next; |
| next = c; |
| *p = c; |
| p = &c->prev; |
| |
| c->insn = insn; |
| c->block = bb->index; |
| |
| if (NONDEBUG_INSN_P (insn)) |
| for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++) |
| { |
| df_ref def = *def_rec; |
| unsigned int regno = DF_REF_REGNO (def); |
| |
| /* Ignore may clobbers because these are generated |
| from calls. However, every other kind of def is |
| added to dead_or_set. */ |
| if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER)) |
| { |
| if (regno < FIRST_PSEUDO_REGISTER) |
| { |
| if (!fixed_regs[regno]) |
| bitmap_set_bit (&c->dead_or_set, regno); |
| } |
| else if (pseudo_for_reload_consideration_p (regno)) |
| bitmap_set_bit (&c->dead_or_set, regno); |
| } |
| |
| if ((regno < FIRST_PSEUDO_REGISTER |
| || reg_renumber[regno] >= 0 |
| || ira_conflicts_p) |
| && (!DF_REF_FLAGS_IS_SET (def, DF_REF_CONDITIONAL))) |
| { |
| rtx reg = DF_REF_REG (def); |
| |
| /* We can model subregs, but not if they are |
| wrapped in ZERO_EXTRACTS. */ |
| if (GET_CODE (reg) == SUBREG |
| && !DF_REF_FLAGS_IS_SET (def, DF_REF_ZERO_EXTRACT)) |
| { |
| unsigned int start = SUBREG_BYTE (reg); |
| unsigned int last = start |
| + GET_MODE_SIZE (GET_MODE (reg)); |
| |
| init_live_subregs |
| (bitmap_bit_p (live_relevant_regs, regno), |
| live_subregs, live_subregs_used, regno, reg); |
| |
| if (!DF_REF_FLAGS_IS_SET |
| (def, DF_REF_STRICT_LOW_PART)) |
| { |
| /* Expand the range to cover entire words. |
| Bytes added here are "don't care". */ |
| start |
| = start / UNITS_PER_WORD * UNITS_PER_WORD; |
| last = ((last + UNITS_PER_WORD - 1) |
| / UNITS_PER_WORD * UNITS_PER_WORD); |
| } |
| |
| /* Ignore the paradoxical bits. */ |
| if (last > SBITMAP_SIZE (live_subregs[regno])) |
| last = SBITMAP_SIZE (live_subregs[regno]); |
| |
| while (start < last) |
| { |
| bitmap_clear_bit (live_subregs[regno], start); |
| start++; |
| } |
| |
| if (bitmap_empty_p (live_subregs[regno])) |
| { |
| bitmap_clear_bit (live_subregs_used, regno); |
| bitmap_clear_bit (live_relevant_regs, regno); |
| } |
| else |
| /* Set live_relevant_regs here because |
| that bit has to be true to get us to |
| look at the live_subregs fields. */ |
| bitmap_set_bit (live_relevant_regs, regno); |
| } |
| else |
| { |
| /* DF_REF_PARTIAL is generated for |
| subregs, STRICT_LOW_PART, and |
| ZERO_EXTRACT. We handle the subreg |
| case above so here we have to keep from |
| modeling the def as a killing def. */ |
| if (!DF_REF_FLAGS_IS_SET (def, DF_REF_PARTIAL)) |
| { |
| bitmap_clear_bit (live_subregs_used, regno); |
| bitmap_clear_bit (live_relevant_regs, regno); |
| } |
| } |
| } |
| } |
| |
| bitmap_and_compl_into (live_relevant_regs, elim_regset); |
| bitmap_copy (&c->live_throughout, live_relevant_regs); |
| |
| if (NONDEBUG_INSN_P (insn)) |
| for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++) |
| { |
| df_ref use = *use_rec; |
| unsigned int regno = DF_REF_REGNO (use); |
| rtx reg = DF_REF_REG (use); |
| |
| /* DF_REF_READ_WRITE on a use means that this use |
| is fabricated from a def that is a partial set |
| to a multiword reg. Here, we only model the |
| subreg case that is not wrapped in ZERO_EXTRACT |
| precisely so we do not need to look at the |
| fabricated use. */ |
| if (DF_REF_FLAGS_IS_SET (use, DF_REF_READ_WRITE) |
| && !DF_REF_FLAGS_IS_SET (use, DF_REF_ZERO_EXTRACT) |
| && DF_REF_FLAGS_IS_SET (use, DF_REF_SUBREG)) |
| continue; |
| |
| /* Add the last use of each var to dead_or_set. */ |
| if (!bitmap_bit_p (live_relevant_regs, regno)) |
| { |
| if (regno < FIRST_PSEUDO_REGISTER) |
| { |
| if (!fixed_regs[regno]) |
| bitmap_set_bit (&c->dead_or_set, regno); |
| } |
| else if (pseudo_for_reload_consideration_p (regno)) |
| bitmap_set_bit (&c->dead_or_set, regno); |
| } |
| |
| if (regno < FIRST_PSEUDO_REGISTER |
| || pseudo_for_reload_consideration_p (regno)) |
| { |
| if (GET_CODE (reg) == SUBREG |
| && !DF_REF_FLAGS_IS_SET (use, |
| DF_REF_SIGN_EXTRACT |
| | DF_REF_ZERO_EXTRACT)) |
| { |
| unsigned int start = SUBREG_BYTE (reg); |
| unsigned int last = start |
| + GET_MODE_SIZE (GET_MODE (reg)); |
| |
| init_live_subregs |
| (bitmap_bit_p (live_relevant_regs, regno), |
| live_subregs, live_subregs_used, regno, reg); |
| |
| /* Ignore the paradoxical bits. */ |
| if (last > SBITMAP_SIZE (live_subregs[regno])) |
| last = SBITMAP_SIZE (live_subregs[regno]); |
| |
| while (start < last) |
| { |
| bitmap_set_bit (live_subregs[regno], start); |
| start++; |
| } |
| } |
| else |
| /* Resetting the live_subregs_used is |
| effectively saying do not use the subregs |
| because we are reading the whole |
| pseudo. */ |
| bitmap_clear_bit (live_subregs_used, regno); |
| bitmap_set_bit (live_relevant_regs, regno); |
| } |
| } |
| } |
| } |
| |
| /* FIXME!! The following code is a disaster. Reload needs to see the |
| labels and jump tables that are just hanging out in between |
| the basic blocks. See pr33676. */ |
| insn = BB_HEAD (bb); |
| |
| /* Skip over the barriers and cruft. */ |
| while (insn && (BARRIER_P (insn) || NOTE_P (insn) |
| || BLOCK_FOR_INSN (insn) == bb)) |
| insn = PREV_INSN (insn); |
| |
| /* While we add anything except barriers and notes, the focus is |
| to get the labels and jump tables into the |
| reload_insn_chain. */ |
| while (insn) |
| { |
| if (!NOTE_P (insn) && !BARRIER_P (insn)) |
| { |
| if (BLOCK_FOR_INSN (insn)) |
| break; |
| |
| c = new_insn_chain (); |
| c->next = next; |
| next = c; |
| *p = c; |
| p = &c->prev; |
| |
| /* The block makes no sense here, but it is what the old |
| code did. */ |
| c->block = bb->index; |
| c->insn = insn; |
| bitmap_copy (&c->live_throughout, live_relevant_regs); |
| } |
| insn = PREV_INSN (insn); |
| } |
| } |
| |
| reload_insn_chain = c; |
| *p = NULL; |
| |
| for (i = 0; i < (unsigned int) max_regno; i++) |
| if (live_subregs[i] != NULL) |
| sbitmap_free (live_subregs[i]); |
| free (live_subregs); |
| BITMAP_FREE (live_subregs_used); |
| BITMAP_FREE (live_relevant_regs); |
| BITMAP_FREE (elim_regset); |
| |
| if (dump_file) |
| print_insn_chains (dump_file); |
| } |
| |
| /* Examine the rtx found in *LOC, which is read or written to as determined |
| by TYPE. Return false if we find a reason why an insn containing this |
| rtx should not be moved (such as accesses to non-constant memory), true |
| otherwise. */ |
| static bool |
| rtx_moveable_p (rtx *loc, enum op_type type) |
| { |
| const char *fmt; |
| rtx x = *loc; |
| enum rtx_code code = GET_CODE (x); |
| int i, j; |
| |
| code = GET_CODE (x); |
| switch (code) |
| { |
| case CONST: |
| CASE_CONST_ANY: |
| case SYMBOL_REF: |
| case LABEL_REF: |
| return true; |
| |
| case PC: |
| return type == OP_IN; |
| |
| case CC0: |
| return false; |
| |
| case REG: |
| if (x == frame_pointer_rtx) |
| return true; |
| if (HARD_REGISTER_P (x)) |
| return false; |
| |
| return true; |
| |
| case MEM: |
| if (type == OP_IN && MEM_READONLY_P (x)) |
| return rtx_moveable_p (&XEXP (x, 0), OP_IN); |
| return false; |
| |
| case SET: |
| return (rtx_moveable_p (&SET_SRC (x), OP_IN) |
| && rtx_moveable_p (&SET_DEST (x), OP_OUT)); |
| |
| case STRICT_LOW_PART: |
| return rtx_moveable_p (&XEXP (x, 0), OP_OUT); |
| |
| case ZERO_EXTRACT: |
| case SIGN_EXTRACT: |
| return (rtx_moveable_p (&XEXP (x, 0), type) |
| && rtx_moveable_p (&XEXP (x, 1), OP_IN) |
| && rtx_moveable_p (&XEXP (x, 2), OP_IN)); |
| |
| case CLOBBER: |
| return rtx_moveable_p (&SET_DEST (x), OP_OUT); |
| |
| default: |
| break; |
| } |
| |
| fmt = GET_RTX_FORMAT (code); |
| for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| { |
| if (fmt[i] == 'e') |
| { |
| if (!rtx_moveable_p (&XEXP (x, i), type)) |
| return false; |
| } |
| else if (fmt[i] == 'E') |
| for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| { |
| if (!rtx_moveable_p (&XVECEXP (x, i, j), type)) |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /* A wrapper around dominated_by_p, which uses the information in UID_LUID |
| to give dominance relationships between two insns I1 and I2. */ |
| static bool |
| insn_dominated_by_p (rtx i1, rtx i2, int *uid_luid) |
| { |
| basic_block bb1 = BLOCK_FOR_INSN (i1); |
| basic_block bb2 = BLOCK_FOR_INSN (i2); |
| |
| if (bb1 == bb2) |
| return uid_luid[INSN_UID (i2)] < uid_luid[INSN_UID (i1)]; |
| return dominated_by_p (CDI_DOMINATORS, bb1, bb2); |
| } |
| |
| /* Record the range of register numbers added by find_moveable_pseudos. */ |
| int first_moveable_pseudo, last_moveable_pseudo; |
| |
| /* These two vectors hold data for every register added by |
| find_movable_pseudos, with index 0 holding data for the |
| first_moveable_pseudo. */ |
| /* The original home register. */ |
| static vec<rtx> pseudo_replaced_reg; |
| |
| /* Look for instances where we have an instruction that is known to increase |
| register pressure, and whose result is not used immediately. If it is |
| possible to move the instruction downwards to just before its first use, |
| split its lifetime into two ranges. We create a new pseudo to compute the |
| value, and emit a move instruction just before the first use. If, after |
| register allocation, the new pseudo remains unallocated, the function |
| move_unallocated_pseudos then deletes the move instruction and places |
| the computation just before the first use. |
| |
| Such a move is safe and profitable if all the input registers remain live |
| and unchanged between the original computation and its first use. In such |
| a situation, the computation is known to increase register pressure, and |
| moving it is known to at least not worsen it. |
| |
| We restrict moves to only those cases where a register remains unallocated, |
| in order to avoid interfering too much with the instruction schedule. As |
| an exception, we may move insns which only modify their input register |
| (typically induction variables), as this increases the freedom for our |
| intended transformation, and does not limit the second instruction |
| scheduler pass. */ |
| |
| static void |
| find_moveable_pseudos (void) |
| { |
| unsigned i; |
| int max_regs = max_reg_num (); |
| int max_uid = get_max_uid (); |
| basic_block bb; |
| int *uid_luid = XNEWVEC (int, max_uid); |
| rtx *closest_uses = XNEWVEC (rtx, max_regs); |
| /* A set of registers which are live but not modified throughout a block. */ |
| bitmap_head *bb_transp_live = XNEWVEC (bitmap_head, |
| last_basic_block_for_fn (cfun)); |
| /* A set of registers which only exist in a given basic block. */ |
| bitmap_head *bb_local = XNEWVEC (bitmap_head, |
| last_basic_block_for_fn (cfun)); |
| /* A set of registers which are set once, in an instruction that can be |
| moved freely downwards, but are otherwise transparent to a block. */ |
| bitmap_head *bb_moveable_reg_sets = XNEWVEC (bitmap_head, |
| last_basic_block_for_fn (cfun)); |
| bitmap_head live, used, set, interesting, unusable_as_input; |
| bitmap_iterator bi; |
| bitmap_initialize (&interesting, 0); |
| |
| first_moveable_pseudo = max_regs; |
| pseudo_replaced_reg.release (); |
| pseudo_replaced_reg.safe_grow_cleared (max_regs); |
| |
| df_analyze (); |
| calculate_dominance_info (CDI_DOMINATORS); |
| |
| i = 0; |
| bitmap_initialize (&live, 0); |
| bitmap_initialize (&used, 0); |
| bitmap_initialize (&set, 0); |
| bitmap_initialize (&unusable_as_input, 0); |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| rtx insn; |
| bitmap transp = bb_transp_live + bb->index; |
| bitmap moveable = bb_moveable_reg_sets + bb->index; |
| bitmap local = bb_local + bb->index; |
| |
| bitmap_initialize (local, 0); |
| bitmap_initialize (transp, 0); |
| bitmap_initialize (moveable, 0); |
| bitmap_copy (&live, df_get_live_out (bb)); |
| bitmap_and_into (&live, df_get_live_in (bb)); |
| bitmap_copy (transp, &live); |
| bitmap_clear (moveable); |
| bitmap_clear (&live); |
| bitmap_clear (&used); |
| bitmap_clear (&set); |
| FOR_BB_INSNS (bb, insn) |
| if (NONDEBUG_INSN_P (insn)) |
| { |
| df_ref *u_rec, *d_rec; |
| |
| uid_luid[INSN_UID (insn)] = i++; |
| |
| u_rec = DF_INSN_USES (insn); |
| d_rec = DF_INSN_DEFS (insn); |
| if (d_rec[0] != NULL && d_rec[1] == NULL |
| && u_rec[0] != NULL && u_rec[1] == NULL |
| && DF_REF_REGNO (*u_rec) == DF_REF_REGNO (*d_rec) |
| && !bitmap_bit_p (&set, DF_REF_REGNO (*u_rec)) |
| && rtx_moveable_p (&PATTERN (insn), OP_IN)) |
| { |
| unsigned regno = DF_REF_REGNO (*u_rec); |
| bitmap_set_bit (moveable, regno); |
| bitmap_set_bit (&set, regno); |
| bitmap_set_bit (&used, regno); |
| bitmap_clear_bit (transp, regno); |
| continue; |
| } |
| while (*u_rec) |
| { |
| unsigned regno = DF_REF_REGNO (*u_rec); |
| bitmap_set_bit (&used, regno); |
| if (bitmap_clear_bit (moveable, regno)) |
| bitmap_clear_bit (transp, regno); |
| u_rec++; |
| } |
| |
| while (*d_rec) |
| { |
| unsigned regno = DF_REF_REGNO (*d_rec); |
| bitmap_set_bit (&set, regno); |
| bitmap_clear_bit (transp, regno); |
| bitmap_clear_bit (moveable, regno); |
| d_rec++; |
| } |
| } |
| } |
| |
| bitmap_clear (&live); |
| bitmap_clear (&used); |
| bitmap_clear (&set); |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| bitmap local = bb_local + bb->index; |
| rtx insn; |
| |
| FOR_BB_INSNS (bb, insn) |
| if (NONDEBUG_INSN_P (insn)) |
| { |
| rtx def_insn, closest_use, note; |
| df_ref *def_rec, def, use; |
| unsigned regno; |
| bool all_dominated, all_local; |
| enum machine_mode mode; |
| |
| def_rec = DF_INSN_DEFS (insn); |
| /* There must be exactly one def in this insn. */ |
| def = *def_rec; |
| if (!def || def_rec[1] || !single_set (insn)) |
| continue; |
| /* This must be the only definition of the reg. We also limit |
| which modes we deal with so that we can assume we can generate |
| move instructions. */ |
| regno = DF_REF_REGNO (def); |
| mode = GET_MODE (DF_REF_REG (def)); |
| if (DF_REG_DEF_COUNT (regno) != 1 |
| || !DF_REF_INSN_INFO (def) |
| || HARD_REGISTER_NUM_P (regno) |
| || DF_REG_EQ_USE_COUNT (regno) > 0 |
| || (!INTEGRAL_MODE_P (mode) && !FLOAT_MODE_P (mode))) |
| continue; |
| def_insn = DF_REF_INSN (def); |
| |
| for (note = REG_NOTES (def_insn); note; note = XEXP (note, 1)) |
| if (REG_NOTE_KIND (note) == REG_EQUIV && MEM_P (XEXP (note, 0))) |
| break; |
| |
| if (note) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Ignoring reg %d, has equiv memory\n", |
| regno); |
| bitmap_set_bit (&unusable_as_input, regno); |
| continue; |
| } |
| |
| use = DF_REG_USE_CHAIN (regno); |
| all_dominated = true; |
| all_local = true; |
| closest_use = NULL_RTX; |
| for (; use; use = DF_REF_NEXT_REG (use)) |
| { |
| rtx insn; |
| if (!DF_REF_INSN_INFO (use)) |
| { |
| all_dominated = false; |
| all_local = false; |
| break; |
| } |
| insn = DF_REF_INSN (use); |
| if (DEBUG_INSN_P (insn)) |
| continue; |
| if (BLOCK_FOR_INSN (insn) != BLOCK_FOR_INSN (def_insn)) |
| all_local = false; |
| if (!insn_dominated_by_p (insn, def_insn, uid_luid)) |
| all_dominated = false; |
| if (closest_use != insn && closest_use != const0_rtx) |
| { |
| if (closest_use == NULL_RTX) |
| closest_use = insn; |
| else if (insn_dominated_by_p (closest_use, insn, uid_luid)) |
| closest_use = insn; |
| else if (!insn_dominated_by_p (insn, closest_use, uid_luid)) |
| closest_use = const0_rtx; |
| } |
| } |
| if (!all_dominated) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Reg %d not all uses dominated by set\n", |
| regno); |
| continue; |
| } |
| if (all_local) |
| bitmap_set_bit (local, regno); |
| if (closest_use == const0_rtx || closest_use == NULL |
| || next_nonnote_nondebug_insn (def_insn) == closest_use) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Reg %d uninteresting%s\n", regno, |
| closest_use == const0_rtx || closest_use == NULL |
| ? " (no unique first use)" : ""); |
| continue; |
| } |
| #ifdef HAVE_cc0 |
| if (reg_referenced_p (cc0_rtx, PATTERN (closest_use))) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Reg %d: closest user uses cc0\n", |
| regno); |
| continue; |
| } |
| #endif |
| bitmap_set_bit (&interesting, regno); |
| closest_uses[regno] = closest_use; |
| |
| if (dump_file && (all_local || all_dominated)) |
| { |
| fprintf (dump_file, "Reg %u:", regno); |
| if (all_local) |
| fprintf (dump_file, " local to bb %d", bb->index); |
| if (all_dominated) |
| fprintf (dump_file, " def dominates all uses"); |
| if (closest_use != const0_rtx) |
| fprintf (dump_file, " has unique first use"); |
| fputs ("\n", dump_file); |
| } |
| } |
| } |
| |
| EXECUTE_IF_SET_IN_BITMAP (&interesting, 0, i, bi) |
| { |
| df_ref def = DF_REG_DEF_CHAIN (i); |
| rtx def_insn = DF_REF_INSN (def); |
| basic_block def_block = BLOCK_FOR_INSN (def_insn); |
| bitmap def_bb_local = bb_local + def_block->index; |
| bitmap def_bb_moveable = bb_moveable_reg_sets + def_block->index; |
| bitmap def_bb_transp = bb_transp_live + def_block->index; |
| bool local_to_bb_p = bitmap_bit_p (def_bb_local, i); |
| rtx use_insn = closest_uses[i]; |
| df_ref *def_insn_use_rec = DF_INSN_USES (def_insn); |
| bool all_ok = true; |
| bool all_transp = true; |
| |
| if (!REG_P (DF_REF_REG (def))) |
| continue; |
| |
| if (!local_to_bb_p) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Reg %u not local to one basic block\n", |
| i); |
| continue; |
| } |
| if (reg_equiv_init (i) != NULL_RTX) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Ignoring reg %u with equiv init insn\n", |
| i); |
| continue; |
| } |
| if (!rtx_moveable_p (&PATTERN (def_insn), OP_IN)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Found def insn %d for %d to be not moveable\n", |
| INSN_UID (def_insn), i); |
| continue; |
| } |
| if (dump_file) |
| fprintf (dump_file, "Examining insn %d, def for %d\n", |
| INSN_UID (def_insn), i); |
| while (*def_insn_use_rec != NULL) |
| { |
| df_ref use = *def_insn_use_rec; |
| unsigned regno = DF_REF_REGNO (use); |
| if (bitmap_bit_p (&unusable_as_input, regno)) |
| { |
| all_ok = false; |
| if (dump_file) |
| fprintf (dump_file, " found unusable input reg %u.\n", regno); |
| break; |
| } |
| if (!bitmap_bit_p (def_bb_transp, regno)) |
| { |
| if (bitmap_bit_p (def_bb_moveable, regno) |
| && !control_flow_insn_p (use_insn) |
| #ifdef HAVE_cc0 |
| && !sets_cc0_p (use_insn) |
| #endif |
| ) |
| { |
| if (modified_between_p (DF_REF_REG (use), def_insn, use_insn)) |
| { |
| rtx x = NEXT_INSN (def_insn); |
| while (!modified_in_p (DF_REF_REG (use), x)) |
| { |
| gcc_assert (x != use_insn); |
| x = NEXT_INSN (x); |
| } |
| if (dump_file) |
| fprintf (dump_file, " input reg %u modified but insn %d moveable\n", |
| regno, INSN_UID (x)); |
| emit_insn_after (PATTERN (x), use_insn); |
| set_insn_deleted (x); |
| } |
| else |
| { |
| if (dump_file) |
| fprintf (dump_file, " input reg %u modified between def and use\n", |
| regno); |
| all_transp = false; |
| } |
| } |
| else |
| all_transp = false; |
| } |
| |
| def_insn_use_rec++; |
| } |
| if (!all_ok) |
| continue; |
| if (!dbg_cnt (ira_move)) |
| break; |
| if (dump_file) |
| fprintf (dump_file, " all ok%s\n", all_transp ? " and transp" : ""); |
| |
| if (all_transp) |
| { |
| rtx def_reg = DF_REF_REG (def); |
| rtx newreg = ira_create_new_reg (def_reg); |
| if (validate_change (def_insn, DF_REF_REAL_LOC (def), newreg, 0)) |
| { |
| unsigned nregno = REGNO (newreg); |
| emit_insn_before (gen_move_insn (def_reg, newreg), use_insn); |
| nregno -= max_regs; |
| pseudo_replaced_reg[nregno] = def_reg; |
| } |
| } |
| } |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| bitmap_clear (bb_local + bb->index); |
| bitmap_clear (bb_transp_live + bb->index); |
| bitmap_clear (bb_moveable_reg_sets + bb->index); |
| } |
| bitmap_clear (&interesting); |
| bitmap_clear (&unusable_as_input); |
| free (uid_luid); |
| free (closest_uses); |
| free (bb_local); |
| free (bb_transp_live); |
| free (bb_moveable_reg_sets); |
| |
| last_moveable_pseudo = max_reg_num (); |
| |
| fix_reg_equiv_init (); |
| expand_reg_info (); |
| regstat_free_n_sets_and_refs (); |
| regstat_free_ri (); |
| regstat_init_n_sets_and_refs (); |
| regstat_compute_ri (); |
| free_dominance_info (CDI_DOMINATORS); |
| } |
| |
| /* If SET pattern SET is an assignment from a hard register to a pseudo which |
| is live at CALL_DOM (if non-NULL, otherwise this check is omitted), return |
| the destination. Otherwise return NULL. */ |
| |
| static rtx |
| interesting_dest_for_shprep_1 (rtx set, basic_block call_dom) |
| { |
| rtx src = SET_SRC (set); |
| rtx dest = SET_DEST (set); |
| if (!REG_P (src) || !HARD_REGISTER_P (src) |
| || !REG_P (dest) || HARD_REGISTER_P (dest) |
| || (call_dom && !bitmap_bit_p (df_get_live_in (call_dom), REGNO (dest)))) |
| return NULL; |
| return dest; |
| } |
| |
| /* If insn is interesting for parameter range-splitting shring-wrapping |
| preparation, i.e. it is a single set from a hard register to a pseudo, which |
| is live at CALL_DOM (if non-NULL, otherwise this check is omitted), or a |
| parallel statement with only one such statement, return the destination. |
| Otherwise return NULL. */ |
| |
| static rtx |
| interesting_dest_for_shprep (rtx insn, basic_block call_dom) |
| { |
| if (!INSN_P (insn)) |
| return NULL; |
| rtx pat = PATTERN (insn); |
| if (GET_CODE (pat) == SET) |
| return interesting_dest_for_shprep_1 (pat, call_dom); |
| |
| if (GET_CODE (pat) != PARALLEL) |
| return NULL; |
| rtx ret = NULL; |
| for (int i = 0; i < XVECLEN (pat, 0); i++) |
| { |
| rtx sub = XVECEXP (pat, 0, i); |
| if (GET_CODE (sub) == USE || GET_CODE (sub) == CLOBBER) |
| continue; |
| if (GET_CODE (sub) != SET |
| || side_effects_p (sub)) |
| return NULL; |
| rtx dest = interesting_dest_for_shprep_1 (sub, call_dom); |
| if (dest && ret) |
| return NULL; |
| if (dest) |
| ret = dest; |
| } |
| return ret; |
| } |
| |
| /* Split live ranges of pseudos that are loaded from hard registers in the |
| first BB in a BB that dominates all non-sibling call if such a BB can be |
| found and is not in a loop. Return true if the function has made any |
| changes. */ |
| |
| static bool |
| split_live_ranges_for_shrink_wrap (void) |
| { |
| basic_block bb, call_dom = NULL; |
| basic_block first = single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun)); |
| rtx insn, last_interesting_insn = NULL; |
| bitmap_head need_new, reachable; |
| vec<basic_block> queue; |
| |
| if (!flag_shrink_wrap) |
| return false; |
| |
| bitmap_initialize (&need_new, 0); |
| bitmap_initialize (&reachable, 0); |
| queue.create (n_basic_blocks_for_fn (cfun)); |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| FOR_BB_INSNS (bb, insn) |
| if (CALL_P (insn) && !SIBLING_CALL_P (insn)) |
| { |
| if (bb == first) |
| { |
| bitmap_clear (&need_new); |
| bitmap_clear (&reachable); |
| queue.release (); |
| return false; |
| } |
| |
| bitmap_set_bit (&need_new, bb->index); |
| bitmap_set_bit (&reachable, bb->index); |
| queue.quick_push (bb); |
| break; |
| } |
| |
| if (queue.is_empty ()) |
| { |
| bitmap_clear (&need_new); |
| bitmap_clear (&reachable); |
| queue.release (); |
| return false; |
| } |
| |
| while (!queue.is_empty ()) |
| { |
| edge e; |
| edge_iterator ei; |
| |
| bb = queue.pop (); |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
| && bitmap_set_bit (&reachable, e->dest->index)) |
| queue.quick_push (e->dest); |
| } |
| queue.release (); |
| |
| FOR_BB_INSNS (first, insn) |
| { |
| rtx dest = interesting_dest_for_shprep (insn, NULL); |
| if (!dest) |
| continue; |
| |
| if (DF_REG_DEF_COUNT (REGNO (dest)) > 1) |
| { |
| bitmap_clear (&need_new); |
| bitmap_clear (&reachable); |
| return false; |
| } |
| |
| for (df_ref use = DF_REG_USE_CHAIN (REGNO(dest)); |
| use; |
| use = DF_REF_NEXT_REG (use)) |
| { |
| if (NONDEBUG_INSN_P (DF_REF_INSN (use)) |
| && GET_CODE (DF_REF_REG (use)) == SUBREG) |
| { |
| /* This is necessary to avoid hitting an assert at |
| postreload.c:2294 in libstc++ testcases on x86_64-linux. I'm |
| not really sure what the probblem actually is there. */ |
| bitmap_clear (&need_new); |
| bitmap_clear (&reachable); |
| return false; |
| } |
| |
| int ubbi = DF_REF_BB (use)->index; |
| if (bitmap_bit_p (&reachable, ubbi)) |
| bitmap_set_bit (&need_new, ubbi); |
| } |
| last_interesting_insn = insn; |
| } |
| |
| bitmap_clear (&reachable); |
| if (!last_interesting_insn) |
| { |
| bitmap_clear (&need_new); |
| return false; |
| } |
| |
| call_dom = nearest_common_dominator_for_set (CDI_DOMINATORS, &need_new); |
| bitmap_clear (&need_new); |
| if (call_dom == first) |
| return false; |
| |
| loop_optimizer_init (AVOID_CFG_MODIFICATIONS); |
| while (bb_loop_depth (call_dom) > 0) |
| call_dom = get_immediate_dominator (CDI_DOMINATORS, call_dom); |
| loop_optimizer_finalize (); |
| |
| if (call_dom == first) |
| return false; |
| |
| calculate_dominance_info (CDI_POST_DOMINATORS); |
| if (dominated_by_p (CDI_POST_DOMINATORS, first, call_dom)) |
| { |
| free_dominance_info (CDI_POST_DOMINATORS); |
| return false; |
| } |
| free_dominance_info (CDI_POST_DOMINATORS); |
| |
| if (dump_file) |
| fprintf (dump_file, "Will split live ranges of parameters at BB %i\n", |
| call_dom->index); |
| |
| bool ret = false; |
| FOR_BB_INSNS (first, insn) |
| { |
| rtx dest = interesting_dest_for_shprep (insn, call_dom); |
| if (!dest) |
| continue; |
| |
| rtx newreg = NULL_RTX; |
| df_ref use, next; |
| for (use = DF_REG_USE_CHAIN (REGNO (dest)); use; use = next) |
| { |
| rtx uin = DF_REF_INSN (use); |
| next = DF_REF_NEXT_REG (use); |
| |
| basic_block ubb = BLOCK_FOR_INSN (uin); |
| if (ubb == call_dom |
| || dominated_by_p (CDI_DOMINATORS, ubb, call_dom)) |
| { |
| if (!newreg) |
| newreg = ira_create_new_reg (dest); |
| validate_change (uin, DF_REF_REAL_LOC (use), newreg, true); |
| } |
| } |
| |
| if (newreg) |
| { |
| rtx new_move = gen_move_insn (newreg, dest); |
| emit_insn_after (new_move, bb_note (call_dom)); |
| if (dump_file) |
| { |
| fprintf (dump_file, "Split live-range of register "); |
| print_rtl_single (dump_file, dest); |
| } |
| ret = true; |
| } |
| |
| if (insn == last_interesting_insn) |
| break; |
| } |
| apply_change_group (); |
| return ret; |
| } |
| |
| /* Perform the second half of the transformation started in |
| find_moveable_pseudos. We look for instances where the newly introduced |
| pseudo remains unallocated, and remove it by moving the definition to |
| just before its use, replacing the move instruction generated by |
| find_moveable_pseudos. */ |
| static void |
| move_unallocated_pseudos (void) |
| { |
| int i; |
| for (i = first_moveable_pseudo; i < last_moveable_pseudo; i++) |
| if (reg_renumber[i] < 0) |
| { |
| int idx = i - first_moveable_pseudo; |
| rtx other_reg = pseudo_replaced_reg[idx]; |
| rtx def_insn = DF_REF_INSN (DF_REG_DEF_CHAIN (i)); |
| /* The use must follow all definitions of OTHER_REG, so we can |
| insert the new definition immediately after any of them. */ |
| df_ref other_def = DF_REG_DEF_CHAIN (REGNO (other_reg)); |
| rtx move_insn = DF_REF_INSN (other_def); |
| rtx newinsn = emit_insn_after (PATTERN (def_insn), move_insn); |
| rtx set; |
| int success; |
| |
| if (dump_file) |
| fprintf (dump_file, "moving def of %d (insn %d now) ", |
| REGNO (other_reg), INSN_UID (def_insn)); |
| |
| delete_insn (move_insn); |
| while ((other_def = DF_REG_DEF_CHAIN (REGNO (other_reg)))) |
| delete_insn (DF_REF_INSN (other_def)); |
| delete_insn (def_insn); |
| |
| set = single_set (newinsn); |
| success = validate_change (newinsn, &SET_DEST (set), other_reg, 0); |
| gcc_assert (success); |
| if (dump_file) |
| fprintf (dump_file, " %d) rather than keep unallocated replacement %d\n", |
| INSN_UID (newinsn), i); |
| SET_REG_N_REFS (i, 0); |
| } |
| } |
| |
| /* If the backend knows where to allocate pseudos for hard |
| register initial values, register these allocations now. */ |
| static void |
| allocate_initial_values (void) |
| { |
| if (targetm.allocate_initial_value) |
| { |
| rtx hreg, preg, x; |
| int i, regno; |
| |
| for (i = 0; HARD_REGISTER_NUM_P (i); i++) |
| { |
| if (! initial_value_entry (i, &hreg, &preg)) |
| break; |
| |
| x = targetm.allocate_initial_value (hreg); |
| regno = REGNO (preg); |
| if (x && REG_N_SETS (regno) <= 1) |
| { |
| if (MEM_P (x)) |
| reg_equiv_memory_loc (regno) = x; |
| else |
| { |
| basic_block bb; |
| int new_regno; |
| |
| gcc_assert (REG_P (x)); |
| new_regno = REGNO (x); |
| reg_renumber[regno] = new_regno; |
| /* Poke the regno right into regno_reg_rtx so that even |
| fixed regs are accepted. */ |
| SET_REGNO (preg, new_regno); |
| /* Update global register liveness information. */ |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| if (REGNO_REG_SET_P (df_get_live_in (bb), regno)) |
| SET_REGNO_REG_SET (df_get_live_in (bb), new_regno); |
| if (REGNO_REG_SET_P (df_get_live_out (bb), regno)) |
| SET_REGNO_REG_SET (df_get_live_out (bb), new_regno); |
| } |
| } |
| } |
| } |
| |
| gcc_checking_assert (! initial_value_entry (FIRST_PSEUDO_REGISTER, |
| &hreg, &preg)); |
| } |
| } |
| |
| |
| /* True when we use LRA instead of reload pass for the current |
| function. */ |
| bool ira_use_lra_p; |
| |
| /* True if we have allocno conflicts. It is false for non-optimized |
| mode or when the conflict table is too big. */ |
| bool ira_conflicts_p; |
| |
| /* Saved between IRA and reload. */ |
| static int saved_flag_ira_share_spill_slots; |
| |
| /* This is the main entry of IRA. */ |
| static void |
| ira (FILE *f) |
| { |
| bool loops_p; |
| int ira_max_point_before_emit; |
| int rebuild_p; |
| bool saved_flag_caller_saves = flag_caller_saves; |
| enum ira_region saved_flag_ira_region = flag_ira_region; |
| |
| ira_conflicts_p = optimize > 0; |
| |
| ira_use_lra_p = targetm.lra_p (); |
| /* If there are too many pseudos and/or basic blocks (e.g. 10K |
| pseudos and 10K blocks or 100K pseudos and 1K blocks), we will |
| use simplified and faster algorithms in LRA. */ |
| lra_simple_p |
| = (ira_use_lra_p |
| && max_reg_num () >= (1 << 26) / last_basic_block_for_fn (cfun)); |
| if (lra_simple_p) |
| { |
| /* It permits to skip live range splitting in LRA. */ |
| flag_caller_saves = false; |
| /* There is no sense to do regional allocation when we use |
| simplified LRA. */ |
| flag_ira_region = IRA_REGION_ONE; |
| ira_conflicts_p = false; |
| } |
| |
| #ifndef IRA_NO_OBSTACK |
| gcc_obstack_init (&ira_obstack); |
| #endif |
| bitmap_obstack_initialize (&ira_bitmap_obstack); |
| |
| if (flag_caller_saves) |
| init_caller_save (); |
| |
| if (flag_ira_verbose < 10) |
| { |
| internal_flag_ira_verbose = flag_ira_verbose; |
| ira_dump_file = f; |
| } |
| else |
| { |
| internal_flag_ira_verbose = flag_ira_verbose - 10; |
| ira_dump_file = stderr; |
| } |
| |
| setup_prohibited_mode_move_regs (); |
| decrease_live_ranges_number (); |
| df_note_add_problem (); |
| |
| /* DF_LIVE can't be used in the register allocator, too many other |
| parts of the compiler depend on using the "classic" liveness |
| interpretation of the DF_LR problem. See PR38711. |
| Remove the problem, so that we don't spend time updating it in |
| any of the df_analyze() calls during IRA/LRA. */ |
| if (optimize > 1) |
| df_remove_problem (df_live); |
| gcc_checking_assert (df_live == NULL); |
| |
| #ifdef ENABLE_CHECKING |
| df->changeable_flags |= DF_VERIFY_SCHEDULED; |
| #endif |
| df_analyze (); |
| |
| init_reg_equiv (); |
| if (ira_conflicts_p) |
| { |
| calculate_dominance_info (CDI_DOMINATORS); |
| |
| if (split_live_ranges_for_shrink_wrap ()) |
| df_analyze (); |
| |
| free_dominance_info (CDI_DOMINATORS); |
| } |
| |
| df_clear_flags (DF_NO_INSN_RESCAN); |
| |
| regstat_init_n_sets_and_refs (); |
| regstat_compute_ri (); |
| |
| /* If we are not optimizing, then this is the only place before |
| register allocation where dataflow is done. And that is needed |
| to generate these warnings. */ |
| if (warn_clobbered) |
| generate_setjmp_warnings (); |
| |
| /* Determine if the current function is a leaf before running IRA |
| since this can impact optimizations done by the prologue and |
| epilogue thus changing register elimination offsets. */ |
| crtl->is_leaf = leaf_function_p (); |
| |
| if (resize_reg_info () && flag_ira_loop_pressure) |
| ira_set_pseudo_classes (true, ira_dump_file); |
| |
| rebuild_p = update_equiv_regs (); |
| setup_reg_equiv (); |
| setup_reg_equiv_init (); |
| |
| if (optimize && rebuild_p) |
| { |
| timevar_push (TV_JUMP); |
| rebuild_jump_labels (get_insns ()); |
| if (purge_all_dead_edges ()) |
| delete_unreachable_blocks (); |
| timevar_pop (TV_JUMP); |
| } |
| |
| allocated_reg_info_size = max_reg_num (); |
| |
| if (delete_trivially_dead_insns (get_insns (), max_reg_num ())) |
| df_analyze (); |
| |
| /* It is not worth to do such improvement when we use a simple |
| allocation because of -O0 usage or because the function is too |
| big. */ |
| if (ira_conflicts_p) |
| find_moveable_pseudos (); |
| |
| max_regno_before_ira = max_reg_num (); |
| ira_setup_eliminable_regset (); |
| if (flag_shrink_wrap_frame_pointer) |
| ira_init_partial_omit_fp (); |
| |
| ira_overall_cost = ira_reg_cost = ira_mem_cost = 0; |
| ira_load_cost = ira_store_cost = ira_shuffle_cost = 0; |
| ira_move_loops_num = ira_additional_jumps_num = 0; |
| |
| ira_assert (current_loops == NULL); |
| if (flag_ira_region == IRA_REGION_ALL || flag_ira_region == IRA_REGION_MIXED) |
| loop_optimizer_init (AVOID_CFG_MODIFICATIONS | LOOPS_HAVE_RECORDED_EXITS); |
| |
| if (internal_flag_ira_verbose > 0 && ira_dump_file != NULL) |
| fprintf (ira_dump_file, "Building IRA IR\n"); |
| loops_p = ira_build (); |
| |
| ira_assert (ira_conflicts_p || !loops_p); |
| |
| saved_flag_ira_share_spill_slots = flag_ira_share_spill_slots; |
| if (too_high_register_pressure_p () || cfun->calls_setjmp) |
| /* It is just wasting compiler's time to pack spilled pseudos into |
| stack slots in this case -- prohibit it. We also do this if |
| there is setjmp call because a variable not modified between |
| setjmp and longjmp the compiler is required to preserve its |
| value and sharing slots does not guarantee it. */ |
| flag_ira_share_spill_slots = FALSE; |
| |
| ira_color (); |
| |
| ira_max_point_before_emit = ira_max_point; |
| |
| ira_initiate_emit_data (); |
| |
| ira_emit (loops_p); |
| |
| max_regno = max_reg_num (); |
| if (ira_conflicts_p) |
| { |
| if (! loops_p) |
| { |
| if (! ira_use_lra_p) |
| ira_initiate_assign (); |
| } |
| else |
| { |
| expand_reg_info (); |
| |
| if (ira_use_lra_p) |
| { |
| ira_allocno_t a; |
| ira_allocno_iterator ai; |
| |
| FOR_EACH_ALLOCNO (a, ai) |
| { |
| int old_regno = ALLOCNO_REGNO (a); |
| int new_regno = REGNO (ALLOCNO_EMIT_DATA (a)->reg); |
| |
| ALLOCNO_REGNO (a) = new_regno; |
| |
| if (old_regno != new_regno) |
| setup_reg_classes (new_regno, reg_preferred_class (old_regno), |
| reg_alternate_class (old_regno), |
| reg_allocno_class (old_regno)); |
| } |
| |
| } |
| else |
| { |
| if (internal_flag_ira_verbose > 0 && ira_dump_file != NULL) |
| fprintf (ira_dump_file, "Flattening IR\n"); |
| ira_flattening (max_regno_before_ira, ira_max_point_before_emit); |
| } |
| /* New insns were generated: add notes and recalculate live |
| info. */ |
| df_analyze (); |
| |
| /* ??? Rebuild the loop tree, but why? Does the loop tree |
| change if new insns were generated? Can that be handled |
| by updating the loop tree incrementally? */ |
| loop_optimizer_finalize (); |
| free_dominance_info (CDI_DOMINATORS); |
| loop_optimizer_init (AVOID_CFG_MODIFICATIONS |
| | LOOPS_HAVE_RECORDED_EXITS); |
| |
| if (! ira_use_lra_p) |
| { |
| setup_allocno_assignment_flags (); |
| ira_initiate_assign (); |
| ira_reassign_conflict_allocnos (max_regno); |
| } |
| } |
| } |
| |
| ira_finish_emit_data (); |
| |
| setup_reg_renumber (); |
| |
| calculate_allocation_cost (); |
| |
| #ifdef ENABLE_IRA_CHECKING |
| if (ira_conflicts_p) |
| check_allocation (); |
| #endif |
| |
| if (max_regno != max_regno_before_ira) |
| { |
| regstat_free_n_sets_and_refs (); |
| regstat_free_ri (); |
| regstat_init_n_sets_and_refs (); |
| regstat_compute_ri (); |
| } |
| |
| overall_cost_before = ira_overall_cost; |
| if (! ira_conflicts_p) |
| grow_reg_equivs (); |
| else |
| { |
| fix_reg_equiv_init (); |
| |
| #ifdef ENABLE_IRA_CHECKING |
| print_redundant_copies (); |
| #endif |
| |
| ira_spilled_reg_stack_slots_num = 0; |
| ira_spilled_reg_stack_slots |
| = ((struct ira_spilled_reg_stack_slot *) |
| ira_allocate (max_regno |
| * sizeof (struct ira_spilled_reg_stack_slot))); |
| memset (ira_spilled_reg_stack_slots, 0, |
| max_regno * sizeof (struct ira_spilled_reg_stack_slot)); |
| } |
| allocate_initial_values (); |
| |
| /* See comment for find_moveable_pseudos call. */ |
| if (ira_conflicts_p) |
| move_unallocated_pseudos (); |
| |
| /* Restore original values. */ |
| if (lra_simple_p) |
| { |
| flag_caller_saves = saved_flag_caller_saves; |
| flag_ira_region = saved_flag_ira_region; |
| } |
| } |
| |
| static void |
| do_reload (void) |
| { |
| basic_block bb; |
| bool need_dce; |
| |
| if (flag_ira_verbose < 10) |
| ira_dump_file = dump_file; |
| |
| timevar_push (TV_RELOAD); |
| if (ira_use_lra_p) |
| { |
| if (current_loops != NULL) |
| { |
| loop_optimizer_finalize (); |
| free_dominance_info (CDI_DOMINATORS); |
| } |
| FOR_ALL_BB_FN (bb, cfun) |
| bb->loop_father = NULL; |
| current_loops = NULL; |
| |
| if (ira_conflicts_p) |
| ira_free (ira_spilled_reg_stack_slots); |
| |
| ira_destroy (); |
| |
| lra (ira_dump_file); |
| /* ???!!! Move it before lra () when we use ira_reg_equiv in |
| LRA. */ |
| vec_free (reg_equivs); |
| reg_equivs = NULL; |
| need_dce = false; |
| } |
| else |
| { |
| df_set_flags (DF_NO_INSN_RESCAN); |
| build_insn_chain (); |
| |
| need_dce = reload (get_insns (), ira_conflicts_p); |
| |
| } |
| |
| timevar_pop (TV_RELOAD); |
| |
| timevar_push (TV_IRA); |
| |
| if (ira_conflicts_p && ! ira_use_lra_p) |
| { |
| ira_free (ira_spilled_reg_stack_slots); |
| ira_finish_assign (); |
| } |
| |
| if (internal_flag_ira_verbose > 0 && ira_dump_file != NULL |
| && overall_cost_before != ira_overall_cost) |
| fprintf (ira_dump_file, "+++Overall after reload %d\n", ira_overall_cost); |
| |
| flag_ira_share_spill_slots = saved_flag_ira_share_spill_slots; |
| |
| if (! ira_use_lra_p) |
| { |
| ira_destroy (); |
| if (current_loops != NULL) |
| { |
| loop_optimizer_finalize (); |
| free_dominance_info (CDI_DOMINATORS); |
| } |
| FOR_ALL_BB_FN (bb, cfun) |
| bb->loop_father = NULL; |
| current_loops = NULL; |
| |
| regstat_free_ri (); |
| regstat_free_n_sets_and_refs (); |
| } |
| |
| if (optimize) |
| cleanup_cfg (CLEANUP_EXPENSIVE); |
| |
| finish_reg_equiv (); |
| |
| bitmap_obstack_release (&ira_bitmap_obstack); |
| #ifndef IRA_NO_OBSTACK |
| obstack_free (&ira_obstack, NULL); |
| #endif |
| |
| if (frame_pointer_partially_needed) |
| SET_HARD_REG_BIT (regs_invalidated_by_call, HARD_FRAME_POINTER_REGNUM); |
| |
| /* The code after the reload has changed so much that at this point |
| we might as well just rescan everything. Note that |
| df_rescan_all_insns is not going to help here because it does not |
| touch the artificial uses and defs. */ |
| df_finish_pass (true); |
| df_scan_alloc (NULL); |
| df_scan_blocks (); |
| |
| if (optimize > 1) |
| { |
| df_live_add_problem (); |
| df_live_set_all_dirty (); |
| } |
| |
| if (optimize) |
| df_analyze (); |
| |
| if (need_dce && optimize) |
| run_fast_dce (); |
| |
| /* Diagnose uses of the hard frame pointer when it is used as a global |
| register. Often we can get away with letting the user appropriate |
| the frame pointer, but we should let them know when code generation |
| makes that impossible. */ |
| if (global_regs[HARD_FRAME_POINTER_REGNUM] && frame_pointer_needed) |
| { |
| tree decl = global_regs_decl[HARD_FRAME_POINTER_REGNUM]; |
| error_at (DECL_SOURCE_LOCATION (current_function_decl), |
| "frame pointer required, but reserved"); |
| inform (DECL_SOURCE_LOCATION (decl), "for %qD", decl); |
| } |
| |
| timevar_pop (TV_IRA); |
| } |
| |
| /* Run the integrated register allocator. */ |
| static unsigned int |
| rest_of_handle_ira (void) |
| { |
| ira (dump_file); |
| return 0; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_ira = |
| { |
| RTL_PASS, /* type */ |
| "ira", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| false, /* has_gate */ |
| true, /* has_execute */ |
| TV_IRA, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| TODO_do_not_ggc_collect, /* todo_flags_finish */ |
| }; |
| |
| class pass_ira : public rtl_opt_pass |
| { |
| public: |
| pass_ira (gcc::context *ctxt) |
| : rtl_opt_pass (pass_data_ira, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| unsigned int execute () { return rest_of_handle_ira (); } |
| |
| }; // class pass_ira |
| |
| } // anon namespace |
| |
| rtl_opt_pass * |
| make_pass_ira (gcc::context *ctxt) |
| { |
| return new pass_ira (ctxt); |
| } |
| |
| static unsigned int |
| rest_of_handle_reload (void) |
| { |
| do_reload (); |
| return 0; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_reload = |
| { |
| RTL_PASS, /* type */ |
| "reload", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| false, /* has_gate */ |
| true, /* has_execute */ |
| TV_RELOAD, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0, /* todo_flags_finish */ |
| }; |
| |
| class pass_reload : public rtl_opt_pass |
| { |
| public: |
| pass_reload (gcc::context *ctxt) |
| : rtl_opt_pass (pass_data_reload, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| unsigned int execute () { return rest_of_handle_reload (); } |
| |
| }; // class pass_reload |
| |
| } // anon namespace |
| |
| rtl_opt_pass * |
| make_pass_reload (gcc::context *ctxt) |
| { |
| return new pass_reload (ctxt); |
| } |