blob: cb8190b027a6e9d2c34b9bbf9183e6d0c4e03de6 [file] [log] [blame]
 /* Global, SSA-based optimizations using mathematical identities. Copyright (C) 2005, 2006, 2007, 2008 Free Software Foundation, Inc. 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 . */ /* Currently, the only mini-pass in this file tries to CSE reciprocal operations. These are common in sequences such as this one: modulus = sqrt(x*x + y*y + z*z); x = x / modulus; y = y / modulus; z = z / modulus; that can be optimized to modulus = sqrt(x*x + y*y + z*z); rmodulus = 1.0 / modulus; x = x * rmodulus; y = y * rmodulus; z = z * rmodulus; We do this for loop invariant divisors, and with this pass whenever we notice that a division has the same divisor multiple times. Of course, like in PRE, we don't insert a division if a dominator already has one. However, this cannot be done as an extension of PRE for several reasons. First of all, with some experiments it was found out that the transformation is not always useful if there are only two divisions hy the same divisor. This is probably because modern processors can pipeline the divisions; on older, in-order processors it should still be effective to optimize two divisions by the same number. We make this a param, and it shall be called N in the remainder of this comment. Second, if trapping math is active, we have less freedom on where to insert divisions: we can only do so in basic blocks that already contain one. (If divisions don't trap, instead, we can insert divisions elsewhere, which will be in blocks that are common dominators of those that have the division). We really don't want to compute the reciprocal unless a division will be found. To do this, we won't insert the division in a basic block that has less than N divisions *post-dominating* it. The algorithm constructs a subset of the dominator tree, holding the blocks containing the divisions and the common dominators to them, and walk it twice. The first walk is in post-order, and it annotates each block with the number of divisions that post-dominate it: this gives information on where divisions can be inserted profitably. The second walk is in pre-order, and it inserts divisions as explained above, and replaces divisions by multiplications. In the best case, the cost of the pass is O(n_statements). In the worst-case, the cost is due to creating the dominator tree subset, with a cost of O(n_basic_blocks ^ 2); however this can only happen for n_statements / n_basic_blocks statements. So, the amortized cost of creating the dominator tree subset is O(n_basic_blocks) and the worst-case cost of the pass is O(n_statements * n_basic_blocks). More practically, the cost will be small because there are few divisions, and they tend to be in the same basic block, so insert_bb is called very few times. If we did this using domwalk.c, an efficient implementation would have to work on all the variables in a single pass, because we could not work on just a subset of the dominator tree, as we do now, and the cost would also be something like O(n_statements * n_basic_blocks). The data structures would be more complex in order to work on all the variables in a single pass. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "flags.h" #include "tree.h" #include "tree-flow.h" #include "real.h" #include "timevar.h" #include "tree-pass.h" #include "alloc-pool.h" #include "basic-block.h" #include "target.h" /* This structure represents one basic block that either computes a division, or is a common dominator for basic block that compute a division. */ struct occurrence { /* The basic block represented by this structure. */ basic_block bb; /* If non-NULL, the SSA_NAME holding the definition for a reciprocal inserted in BB. */ tree recip_def; /* If non-NULL, the GIMPLE_ASSIGN for a reciprocal computation that was inserted in BB. */ gimple recip_def_stmt; /* Pointer to a list of "struct occurrence"s for blocks dominated by BB. */ struct occurrence *children; /* Pointer to the next "struct occurrence"s in the list of blocks sharing a common dominator. */ struct occurrence *next; /* The number of divisions that are in BB before compute_merit. The number of divisions that are in BB or post-dominate it after compute_merit. */ int num_divisions; /* True if the basic block has a division, false if it is a common dominator for basic blocks that do. If it is false and trapping math is active, BB is not a candidate for inserting a reciprocal. */ bool bb_has_division; }; /* The instance of "struct occurrence" representing the highest interesting block in the dominator tree. */ static struct occurrence *occ_head; /* Allocation pool for getting instances of "struct occurrence". */ static alloc_pool occ_pool; /* Allocate and return a new struct occurrence for basic block BB, and whose children list is headed by CHILDREN. */ static struct occurrence * occ_new (basic_block bb, struct occurrence *children) { struct occurrence *occ; bb->aux = occ = (struct occurrence *) pool_alloc (occ_pool); memset (occ, 0, sizeof (struct occurrence)); occ->bb = bb; occ->children = children; return occ; } /* Insert NEW_OCC into our subset of the dominator tree. P_HEAD points to a list of "struct occurrence"s, one per basic block, having IDOM as their common dominator. We try to insert NEW_OCC as deep as possible in the tree, and we also insert any other block that is a common dominator for BB and one block already in the tree. */ static void insert_bb (struct occurrence *new_occ, basic_block idom, struct occurrence **p_head) { struct occurrence *occ, **p_occ; for (p_occ = p_head; (occ = *p_occ) != NULL; ) { basic_block bb = new_occ->bb, occ_bb = occ->bb; basic_block dom = nearest_common_dominator (CDI_DOMINATORS, occ_bb, bb); if (dom == bb) { /* BB dominates OCC_BB. OCC becomes NEW_OCC's child: remove OCC from its list. */ *p_occ = occ->next; occ->next = new_occ->children; new_occ->children = occ; /* Try the next block (it may as well be dominated by BB). */ } else if (dom == occ_bb) { /* OCC_BB dominates BB. Tail recurse to look deeper. */ insert_bb (new_occ, dom, &occ->children); return; } else if (dom != idom) { gcc_assert (!dom->aux); /* There is a dominator between IDOM and BB, add it and make two children out of NEW_OCC and OCC. First, remove OCC from its list. */ *p_occ = occ->next; new_occ->next = occ; occ->next = NULL; /* None of the previous blocks has DOM as a dominator: if we tail recursed, we would reexamine them uselessly. Just switch BB with DOM, and go on looking for blocks dominated by DOM. */ new_occ = occ_new (dom, new_occ); } else { /* Nothing special, go on with the next element. */ p_occ = &occ->next; } } /* No place was found as a child of IDOM. Make BB a sibling of IDOM. */ new_occ->next = *p_head; *p_head = new_occ; } /* Register that we found a division in BB. */ static inline void register_division_in (basic_block bb) { struct occurrence *occ; occ = (struct occurrence *) bb->aux; if (!occ) { occ = occ_new (bb, NULL); insert_bb (occ, ENTRY_BLOCK_PTR, &occ_head); } occ->bb_has_division = true; occ->num_divisions++; } /* Compute the number of divisions that postdominate each block in OCC and its children. */ static void compute_merit (struct occurrence *occ) { struct occurrence *occ_child; basic_block dom = occ->bb; for (occ_child = occ->children; occ_child; occ_child = occ_child->next) { basic_block bb; if (occ_child->children) compute_merit (occ_child); if (flag_exceptions) bb = single_noncomplex_succ (dom); else bb = dom; if (dominated_by_p (CDI_POST_DOMINATORS, bb, occ_child->bb)) occ->num_divisions += occ_child->num_divisions; } } /* Return whether USE_STMT is a floating-point division by DEF. */ static inline bool is_division_by (gimple use_stmt, tree def) { return is_gimple_assign (use_stmt) && gimple_assign_rhs_code (use_stmt) == RDIV_EXPR && gimple_assign_rhs2 (use_stmt) == def /* Do not recognize x / x as valid division, as we are getting confused later by replacing all immediate uses x in such a stmt. */ && gimple_assign_rhs1 (use_stmt) != def; } /* Walk the subset of the dominator tree rooted at OCC, setting the RECIP_DEF field to a definition of 1.0 / DEF that can be used in the given basic block. The field may be left NULL, of course, if it is not possible or profitable to do the optimization. DEF_BSI is an iterator pointing at the statement defining DEF. If RECIP_DEF is set, a dominator already has a computation that can be used. */ static void insert_reciprocals (gimple_stmt_iterator *def_gsi, struct occurrence *occ, tree def, tree recip_def, int threshold) { tree type; gimple new_stmt; gimple_stmt_iterator gsi; struct occurrence *occ_child; if (!recip_def && (occ->bb_has_division || !flag_trapping_math) && occ->num_divisions >= threshold) { /* Make a variable with the replacement and substitute it. */ type = TREE_TYPE (def); recip_def = make_rename_temp (type, "reciptmp"); new_stmt = gimple_build_assign_with_ops (RDIV_EXPR, recip_def, build_one_cst (type), def); if (occ->bb_has_division) { /* Case 1: insert before an existing division. */ gsi = gsi_after_labels (occ->bb); while (!gsi_end_p (gsi) && !is_division_by (gsi_stmt (gsi), def)) gsi_next (&gsi); gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); } else if (def_gsi && occ->bb == def_gsi->bb) { /* Case 2: insert right after the definition. Note that this will never happen if the definition statement can throw, because in that case the sole successor of the statement's basic block will dominate all the uses as well. */ gsi_insert_after (def_gsi, new_stmt, GSI_NEW_STMT); } else { /* Case 3: insert in a basic block not containing defs/uses. */ gsi = gsi_after_labels (occ->bb); gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); } occ->recip_def_stmt = new_stmt; } occ->recip_def = recip_def; for (occ_child = occ->children; occ_child; occ_child = occ_child->next) insert_reciprocals (def_gsi, occ_child, def, recip_def, threshold); } /* Replace the division at USE_P with a multiplication by the reciprocal, if possible. */ static inline void replace_reciprocal (use_operand_p use_p) { gimple use_stmt = USE_STMT (use_p); basic_block bb = gimple_bb (use_stmt); struct occurrence *occ = (struct occurrence *) bb->aux; if (optimize_bb_for_speed_p (bb) && occ->recip_def && use_stmt != occ->recip_def_stmt) { gimple_assign_set_rhs_code (use_stmt, MULT_EXPR); SET_USE (use_p, occ->recip_def); fold_stmt_inplace (use_stmt); update_stmt (use_stmt); } } /* Free OCC and return one more "struct occurrence" to be freed. */ static struct occurrence * free_bb (struct occurrence *occ) { struct occurrence *child, *next; /* First get the two pointers hanging off OCC. */ next = occ->next; child = occ->children; occ->bb->aux = NULL; pool_free (occ_pool, occ); /* Now ensure that we don't recurse unless it is necessary. */ if (!child) return next; else { while (next) next = free_bb (next); return child; } } /* Look for floating-point divisions among DEF's uses, and try to replace them by multiplications with the reciprocal. Add as many statements computing the reciprocal as needed. DEF must be a GIMPLE register of a floating-point type. */ static void execute_cse_reciprocals_1 (gimple_stmt_iterator *def_gsi, tree def) { use_operand_p use_p; imm_use_iterator use_iter; struct occurrence *occ; int count = 0, threshold; gcc_assert (FLOAT_TYPE_P (TREE_TYPE (def)) && is_gimple_reg (def)); FOR_EACH_IMM_USE_FAST (use_p, use_iter, def) { gimple use_stmt = USE_STMT (use_p); if (is_division_by (use_stmt, def)) { register_division_in (gimple_bb (use_stmt)); count++; } } /* Do the expensive part only if we can hope to optimize something. */ threshold = targetm.min_divisions_for_recip_mul (TYPE_MODE (TREE_TYPE (def))); if (count >= threshold) { gimple use_stmt; for (occ = occ_head; occ; occ = occ->next) { compute_merit (occ); insert_reciprocals (def_gsi, occ, def, NULL, threshold); } FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, def) { if (is_division_by (use_stmt, def)) { FOR_EACH_IMM_USE_ON_STMT (use_p, use_iter) replace_reciprocal (use_p); } } } for (occ = occ_head; occ; ) occ = free_bb (occ); occ_head = NULL; } static bool gate_cse_reciprocals (void) { return optimize && flag_reciprocal_math; } /* Go through all the floating-point SSA_NAMEs, and call execute_cse_reciprocals_1 on each of them. */ static unsigned int execute_cse_reciprocals (void) { basic_block bb; tree arg; occ_pool = create_alloc_pool ("dominators for recip", sizeof (struct occurrence), n_basic_blocks / 3 + 1); calculate_dominance_info (CDI_DOMINATORS); calculate_dominance_info (CDI_POST_DOMINATORS); #ifdef ENABLE_CHECKING FOR_EACH_BB (bb) gcc_assert (!bb->aux); #endif for (arg = DECL_ARGUMENTS (cfun->decl); arg; arg = TREE_CHAIN (arg)) if (gimple_default_def (cfun, arg) && FLOAT_TYPE_P (TREE_TYPE (arg)) && is_gimple_reg (arg)) execute_cse_reciprocals_1 (NULL, gimple_default_def (cfun, arg)); FOR_EACH_BB (bb) { gimple_stmt_iterator gsi; gimple phi; tree def; for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { phi = gsi_stmt (gsi); def = PHI_RESULT (phi); if (FLOAT_TYPE_P (TREE_TYPE (def)) && is_gimple_reg (def)) execute_cse_reciprocals_1 (NULL, def); } for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); if (gimple_has_lhs (stmt) && (def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF)) != NULL && FLOAT_TYPE_P (TREE_TYPE (def)) && TREE_CODE (def) == SSA_NAME) execute_cse_reciprocals_1 (&gsi, def); } if (optimize_bb_for_size_p (bb)) continue; /* Scan for a/func(b) and convert it to reciprocal a*rfunc(b). */ for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); tree fndecl; if (is_gimple_assign (stmt) && gimple_assign_rhs_code (stmt) == RDIV_EXPR) { tree arg1 = gimple_assign_rhs2 (stmt); gimple stmt1; if (TREE_CODE (arg1) != SSA_NAME) continue; stmt1 = SSA_NAME_DEF_STMT (arg1); if (is_gimple_call (stmt1) && gimple_call_lhs (stmt1) && (fndecl = gimple_call_fndecl (stmt1)) && (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL || DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD)) { enum built_in_function code; bool md_code, fail; imm_use_iterator ui; use_operand_p use_p; code = DECL_FUNCTION_CODE (fndecl); md_code = DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD; fndecl = targetm.builtin_reciprocal (code, md_code, false); if (!fndecl) continue; /* Check that all uses of the SSA name are divisions, otherwise replacing the defining statement will do the wrong thing. */ fail = false; FOR_EACH_IMM_USE_FAST (use_p, ui, arg1) { gimple stmt2 = USE_STMT (use_p); if (!is_gimple_assign (stmt2) || gimple_assign_rhs_code (stmt2) != RDIV_EXPR || gimple_assign_rhs1 (stmt2) == arg1 || gimple_assign_rhs2 (stmt2) != arg1) { fail = true; break; } } if (fail) continue; gimple_call_set_fndecl (stmt1, fndecl); update_stmt (stmt1); FOR_EACH_IMM_USE_STMT (stmt, ui, arg1) { gimple_assign_set_rhs_code (stmt, MULT_EXPR); fold_stmt_inplace (stmt); update_stmt (stmt); } } } } } free_dominance_info (CDI_DOMINATORS); free_dominance_info (CDI_POST_DOMINATORS); free_alloc_pool (occ_pool); return 0; } struct gimple_opt_pass pass_cse_reciprocals = { { GIMPLE_PASS, "recip", /* name */ gate_cse_reciprocals, /* gate */ execute_cse_reciprocals, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ 0, /* tv_id */ PROP_ssa, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ TODO_dump_func | TODO_update_ssa | TODO_verify_ssa | TODO_verify_stmts /* todo_flags_finish */ } }; /* Records an occurrence at statement USE_STMT in the vector of trees STMTS if it is dominated by *TOP_BB or dominates it or this basic block is not yet initialized. Returns true if the occurrence was pushed on the vector. Adjusts *TOP_BB to be the basic block dominating all statements in the vector. */ static bool maybe_record_sincos (VEC(gimple, heap) **stmts, basic_block *top_bb, gimple use_stmt) { basic_block use_bb = gimple_bb (use_stmt); if (*top_bb && (*top_bb == use_bb || dominated_by_p (CDI_DOMINATORS, use_bb, *top_bb))) VEC_safe_push (gimple, heap, *stmts, use_stmt); else if (!*top_bb || dominated_by_p (CDI_DOMINATORS, *top_bb, use_bb)) { VEC_safe_push (gimple, heap, *stmts, use_stmt); *top_bb = use_bb; } else return false; return true; } /* Look for sin, cos and cexpi calls with the same argument NAME and create a single call to cexpi CSEing the result in this case. We first walk over all immediate uses of the argument collecting statements that we can CSE in a vector and in a second pass replace the statement rhs with a REALPART or IMAGPART expression on the result of the cexpi call we insert before the use statement that dominates all other candidates. */ static void execute_cse_sincos_1 (tree name) { gimple_stmt_iterator gsi; imm_use_iterator use_iter; tree fndecl, res, type; gimple def_stmt, use_stmt, stmt; int seen_cos = 0, seen_sin = 0, seen_cexpi = 0; VEC(gimple, heap) *stmts = NULL; basic_block top_bb = NULL; int i; type = TREE_TYPE (name); FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, name) { if (gimple_code (use_stmt) != GIMPLE_CALL || !gimple_call_lhs (use_stmt) || !(fndecl = gimple_call_fndecl (use_stmt)) || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL) continue; switch (DECL_FUNCTION_CODE (fndecl)) { CASE_FLT_FN (BUILT_IN_COS): seen_cos |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0; break; CASE_FLT_FN (BUILT_IN_SIN): seen_sin |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0; break; CASE_FLT_FN (BUILT_IN_CEXPI): seen_cexpi |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0; break; default:; } } if (seen_cos + seen_sin + seen_cexpi <= 1) { VEC_free(gimple, heap, stmts); return; } /* Simply insert cexpi at the beginning of top_bb but not earlier than the name def statement. */ fndecl = mathfn_built_in (type, BUILT_IN_CEXPI); if (!fndecl) return; res = make_rename_temp (TREE_TYPE (TREE_TYPE (fndecl)), "sincostmp"); stmt = gimple_build_call (fndecl, 1, name); gimple_call_set_lhs (stmt, res); def_stmt = SSA_NAME_DEF_STMT (name); if (!SSA_NAME_IS_DEFAULT_DEF (name) && gimple_code (def_stmt) != GIMPLE_PHI && gimple_bb (def_stmt) == top_bb) { gsi = gsi_for_stmt (def_stmt); gsi_insert_after (&gsi, stmt, GSI_SAME_STMT); } else { gsi = gsi_after_labels (top_bb); gsi_insert_before (&gsi, stmt, GSI_SAME_STMT); } update_stmt (stmt); /* And adjust the recorded old call sites. */ for (i = 0; VEC_iterate(gimple, stmts, i, use_stmt); ++i) { tree rhs = NULL; fndecl = gimple_call_fndecl (use_stmt); switch (DECL_FUNCTION_CODE (fndecl)) { CASE_FLT_FN (BUILT_IN_COS): rhs = fold_build1 (REALPART_EXPR, type, res); break; CASE_FLT_FN (BUILT_IN_SIN): rhs = fold_build1 (IMAGPART_EXPR, type, res); break; CASE_FLT_FN (BUILT_IN_CEXPI): rhs = res; break; default:; gcc_unreachable (); } /* Replace call with a copy. */ stmt = gimple_build_assign (gimple_call_lhs (use_stmt), rhs); gsi = gsi_for_stmt (use_stmt); gsi_insert_after (&gsi, stmt, GSI_SAME_STMT); gsi_remove (&gsi, true); } VEC_free(gimple, heap, stmts); } /* Go through all calls to sin, cos and cexpi and call execute_cse_sincos_1 on the SSA_NAME argument of each of them. */ static unsigned int execute_cse_sincos (void) { basic_block bb; calculate_dominance_info (CDI_DOMINATORS); FOR_EACH_BB (bb) { gimple_stmt_iterator gsi; for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); tree fndecl; if (is_gimple_call (stmt) && gimple_call_lhs (stmt) && (fndecl = gimple_call_fndecl (stmt)) && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL) { tree arg; switch (DECL_FUNCTION_CODE (fndecl)) { CASE_FLT_FN (BUILT_IN_COS): CASE_FLT_FN (BUILT_IN_SIN): CASE_FLT_FN (BUILT_IN_CEXPI): arg = gimple_call_arg (stmt, 0); if (TREE_CODE (arg) == SSA_NAME) execute_cse_sincos_1 (arg); break; default:; } } } } free_dominance_info (CDI_DOMINATORS); return 0; } static bool gate_cse_sincos (void) { /* Make sure we have either sincos or cexp. */ return (TARGET_HAS_SINCOS || TARGET_C99_FUNCTIONS) && optimize; } struct gimple_opt_pass pass_cse_sincos = { { GIMPLE_PASS, "sincos", /* name */ gate_cse_sincos, /* gate */ execute_cse_sincos, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ 0, /* tv_id */ PROP_ssa, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ TODO_dump_func | TODO_update_ssa | TODO_verify_ssa | TODO_verify_stmts /* todo_flags_finish */ } }; /* Find all expressions in the form of sqrt(a/b) and convert them to rsqrt(b/a). */ static unsigned int execute_convert_to_rsqrt (void) { basic_block bb; FOR_EACH_BB (bb) { gimple_stmt_iterator gsi; for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); tree fndecl; if (is_gimple_call (stmt) && gimple_call_lhs (stmt) && (fndecl = gimple_call_fndecl (stmt)) && (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL || DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD)) { enum built_in_function code; bool md_code; tree arg1; gimple stmt1; code = DECL_FUNCTION_CODE (fndecl); md_code = DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD; fndecl = targetm.builtin_reciprocal (code, md_code, true); if (!fndecl) continue; arg1 = gimple_call_arg (stmt, 0); if (TREE_CODE (arg1) != SSA_NAME) continue; stmt1 = SSA_NAME_DEF_STMT (arg1); if (is_gimple_assign (stmt1) && gimple_assign_rhs_code (stmt1) == RDIV_EXPR) { tree arg10, arg11; arg10 = gimple_assign_rhs1 (stmt1); arg11 = gimple_assign_rhs2 (stmt1); /* Swap operands of RDIV_EXPR. */ gimple_assign_set_rhs1 (stmt1, arg11); gimple_assign_set_rhs2 (stmt1, arg10); fold_stmt_inplace (stmt1); update_stmt (stmt1); gimple_call_set_fndecl (stmt, fndecl); update_stmt (stmt); } } } } return 0; } static bool gate_convert_to_rsqrt (void) { return flag_unsafe_math_optimizations && optimize; } struct gimple_opt_pass pass_convert_to_rsqrt = { { GIMPLE_PASS, "rsqrt", /* name */ gate_convert_to_rsqrt, /* gate */ execute_convert_to_rsqrt, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ 0, /* tv_id */ PROP_ssa, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ TODO_dump_func | TODO_update_ssa | TODO_verify_ssa | TODO_verify_stmts /* todo_flags_finish */ } };