| /* Target-dependent code for the MIPS architecture running on IRIX, |
| for GDB, the GNU Debugger. |
| |
| Copyright (C) 2002-2013 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program 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 of the License, or |
| (at your option) any later version. |
| |
| This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "defs.h" |
| #include "osabi.h" |
| #include <string.h> |
| #include "solib.h" |
| #include "solib-irix.h" |
| #include "elf-bfd.h" |
| #include "mips-tdep.h" |
| #include "trad-frame.h" |
| #include "tramp-frame.h" |
| |
| static void |
| mips_irix_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect, |
| void *obj) |
| { |
| enum gdb_osabi *os_ident_ptr = obj; |
| const char *name; |
| unsigned int sectsize; |
| |
| name = bfd_get_section_name (abfd, sect); |
| sectsize = bfd_section_size (abfd, sect); |
| |
| if (strncmp (name, ".MIPS.", 6) == 0 && sectsize > 0) |
| { |
| /* The presence of a section named with a ".MIPS." prefix is |
| indicative of an IRIX binary. */ |
| *os_ident_ptr = GDB_OSABI_IRIX; |
| } |
| } |
| |
| static enum gdb_osabi |
| mips_irix_elf_osabi_sniffer (bfd *abfd) |
| { |
| unsigned int elfosabi; |
| enum gdb_osabi osabi = GDB_OSABI_UNKNOWN; |
| |
| /* If the generic sniffer gets a hit, return and let other sniffers |
| get a crack at it. */ |
| bfd_map_over_sections (abfd, |
| generic_elf_osabi_sniff_abi_tag_sections, |
| &osabi); |
| if (osabi != GDB_OSABI_UNKNOWN) |
| return GDB_OSABI_UNKNOWN; |
| |
| elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI]; |
| |
| if (elfosabi == ELFOSABI_NONE) |
| { |
| /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the |
| file are conforming to the base specification for that machine |
| (there are no OS-specific extensions). In order to determine the |
| real OS in use we must look for OS notes that have been added. |
| |
| For IRIX, we simply look for sections named with .MIPS. as |
| prefixes. */ |
| bfd_map_over_sections (abfd, |
| mips_irix_elf_osabi_sniff_abi_tag_sections, |
| &osabi); |
| } |
| return osabi; |
| } |
| |
| /* Unwinding past the signal handler on mips-irix. |
| |
| Note: The following has only been tested with N32, but can probably |
| be made to work with a small number of adjustments. |
| |
| On mips-irix, the sigcontext_t structure is stored at the base |
| of the frame established by the _sigtramp function. The definition |
| of this structure can be found in <sys/signal.h> (comments have been |
| C++'ified to avoid a collision with the C-style comment delimiters |
| used by this comment): |
| |
| typedef struct sigcontext { |
| __uint32_t sc_regmask; // regs to restore in sigcleanup |
| __uint32_t sc_status; // cp0 status register |
| __uint64_t sc_pc; // pc at time of signal |
| // General purpose registers |
| __uint64_t sc_regs[32]; // processor regs 0 to 31 |
| // Floating point coprocessor state |
| __uint64_t sc_fpregs[32]; // fp regs 0 to 31 |
| __uint32_t sc_ownedfp; // fp has been used |
| __uint32_t sc_fpc_csr; // fpu control and status reg |
| __uint32_t sc_fpc_eir; // fpu exception instruction reg |
| // implementation/revision |
| __uint32_t sc_ssflags; // signal stack state to restore |
| __uint64_t sc_mdhi; // Multiplier hi and low regs |
| __uint64_t sc_mdlo; |
| // System coprocessor registers at time of signal |
| __uint64_t sc_cause; // cp0 cause register |
| __uint64_t sc_badvaddr; // cp0 bad virtual address |
| __uint64_t sc_triggersave; // state of graphics trigger (SGI) |
| sigset_t sc_sigset; // signal mask to restore |
| __uint64_t sc_fp_rounded_result; // for Ieee 754 support |
| __uint64_t sc_pad[31]; |
| } sigcontext_t; |
| |
| The following macros provide the offset of some of the fields |
| used to retrieve the value of the registers before the signal |
| was raised. */ |
| |
| /* The size of the sigtramp frame. The sigtramp frame base can then |
| be computed by adding this size to the SP. */ |
| #define SIGTRAMP_FRAME_SIZE 48 |
| /* The offset in sigcontext_t where the PC is saved. */ |
| #define SIGCONTEXT_PC_OFF 8 |
| /* The offset in sigcontext_t where the GP registers are saved. */ |
| #define SIGCONTEXT_REGS_OFF (SIGCONTEXT_PC_OFF + 8) |
| /* The offset in sigcontext_t where the FP regsiters are saved. */ |
| #define SIGCONTEXT_FPREGS_OFF (SIGCONTEXT_REGS_OFF + 32 * 8) |
| /* The offset in sigcontext_t where the FP CSR register is saved. */ |
| #define SIGCONTEXT_FPCSR_OFF (SIGCONTEXT_FPREGS_OFF + 32 * 8 + 4) |
| /* The offset in sigcontext_t where the multiplier hi register is saved. */ |
| #define SIGCONTEXT_HI_OFF (SIGCONTEXT_FPCSR_OFF + 2 * 4) |
| /* The offset in sigcontext_t where the multiplier lo register is saved. */ |
| #define SIGCONTEXT_LO_OFF (SIGCONTEXT_HI_OFF + 4) |
| |
| /* Implement the "init" routine in struct tramp_frame for the N32 ABI |
| on mips-irix. */ |
| static void |
| mips_irix_n32_tramp_frame_init (const struct tramp_frame *self, |
| struct frame_info *this_frame, |
| struct trad_frame_cache *this_cache, |
| CORE_ADDR func) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| const int num_regs = gdbarch_num_regs (gdbarch); |
| int sp_cooked_regno = num_regs + MIPS_SP_REGNUM; |
| const CORE_ADDR sp = get_frame_register_signed (this_frame, sp_cooked_regno); |
| const CORE_ADDR sigcontext_base = sp + 48; |
| const struct mips_regnum *regs = mips_regnum (gdbarch); |
| int ireg; |
| |
| trad_frame_set_reg_addr (this_cache, regs->pc + gdbarch_num_regs (gdbarch), |
| sigcontext_base + SIGCONTEXT_PC_OFF); |
| |
| for (ireg = 1; ireg < 32; ireg++) |
| trad_frame_set_reg_addr (this_cache, ireg + MIPS_ZERO_REGNUM + num_regs, |
| sigcontext_base + SIGCONTEXT_REGS_OFF + ireg * 8); |
| |
| for (ireg = 0; ireg < 32; ireg++) |
| trad_frame_set_reg_addr (this_cache, ireg + regs->fp0 + num_regs, |
| sigcontext_base + SIGCONTEXT_FPREGS_OFF |
| + ireg * 8); |
| |
| trad_frame_set_reg_addr (this_cache, regs->fp_control_status + num_regs, |
| sigcontext_base + SIGCONTEXT_FPCSR_OFF); |
| |
| trad_frame_set_reg_addr (this_cache, regs->hi + num_regs, |
| sigcontext_base + SIGCONTEXT_HI_OFF); |
| |
| trad_frame_set_reg_addr (this_cache, regs->lo + num_regs, |
| sigcontext_base + SIGCONTEXT_LO_OFF); |
| |
| trad_frame_set_id (this_cache, frame_id_build (sigcontext_base, func)); |
| } |
| |
| /* The tramp_frame structure describing sigtramp frames on mips-irix N32. |
| |
| Note that the list of instructions below is pretty much a pure dump |
| of function _sigtramp on mips-irix. A few instructions are actually |
| not tested (mask set to 0), because a portion of these instructions |
| contain an address which changes due to relocation. We could use |
| a smarter mask that checks the instrutction code alone, but given |
| the number of instructions already being checked, this seemed |
| unnecessary. */ |
| |
| static const struct tramp_frame mips_irix_n32_tramp_frame = |
| { |
| SIGTRAMP_FRAME, |
| 4, |
| { |
| { 0x3c0c8000, -1 }, /* lui t0,0x8000 */ |
| { 0x27bdffd0, -1 }, /* addiu sp,sp,-48 */ |
| { 0x008c6024, -1 }, /* and t0,a0,t0 */ |
| { 0xffa40018, -1 }, /* sd a0,24(sp) */ |
| { 0x00000000, 0 }, /* beqz t0,0xfaefcb8 <_sigtramp+40> */ |
| { 0xffa60028, -1 }, /* sd a2,40(sp) */ |
| { 0x01806027, -1 }, /* nor t0,t0,zero */ |
| { 0xffa00020, -1 }, /* sd zero,32(sp) */ |
| { 0x00000000, 0 }, /* b 0xfaefcbc <_sigtramp+44> */ |
| { 0x008c2024, -1 }, /* and a0,a0,t0 */ |
| { 0xffa60020, -1 }, /* sd a2,32(sp) */ |
| { 0x03e0c025, -1 }, /* move t8,ra */ |
| { 0x00000000, 0 }, /* bal 0xfaefcc8 <_sigtramp+56> */ |
| { 0x00000000, -1 }, /* nop */ |
| { 0x3c0c0007, -1 }, /* lui t0,0x7 */ |
| { 0x00e0c825, -1 }, /* move t9,a3 */ |
| { 0x658c80fc, -1 }, /* daddiu t0,t0,-32516 */ |
| { 0x019f602d, -1 }, /* daddu t0,t0,ra */ |
| { 0x0300f825, -1 }, /* move ra,t8 */ |
| { 0x8d8c9880, -1 }, /* lw t0,-26496(t0) */ |
| { 0x8d8c0000, -1 }, /* lw t0,0(t0) */ |
| { 0x8d8d0000, -1 }, /* lw t1,0(t0) */ |
| { 0xffac0008, -1 }, /* sd t0,8(sp) */ |
| { 0x0320f809, -1 }, /* jalr t9 */ |
| { 0xffad0010, -1 }, /* sd t1,16(sp) */ |
| { 0xdfad0010, -1 }, /* ld t1,16(sp) */ |
| { 0xdfac0008, -1 }, /* ld t0,8(sp) */ |
| { 0xad8d0000, -1 }, /* sw t1,0(t0) */ |
| { 0xdfa40020, -1 }, /* ld a0,32(sp) */ |
| { 0xdfa50028, -1 }, /* ld a1,40(sp) */ |
| { 0xdfa60018, -1 }, /* ld a2,24(sp) */ |
| { 0x24020440, -1 }, /* li v0,1088 */ |
| { 0x0000000c, -1 }, /* syscall */ |
| { TRAMP_SENTINEL_INSN, -1 } |
| }, |
| mips_irix_n32_tramp_frame_init |
| }; |
| |
| /* Implement the "init" routine in struct tramp_frame for the stack-based |
| trampolines used on mips-irix. */ |
| |
| static void |
| mips_irix_n32_stack_tramp_frame_init (const struct tramp_frame *self, |
| struct frame_info *this_frame, |
| struct trad_frame_cache *this_cache, |
| CORE_ADDR func) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| const int num_regs = gdbarch_num_regs (gdbarch); |
| int sp_cooked_regno = num_regs + MIPS_SP_REGNUM; |
| const CORE_ADDR sp = get_frame_register_signed (this_frame, sp_cooked_regno); |
| |
| /* The previous frame's PC is stored in RA. */ |
| trad_frame_set_reg_realreg (this_cache, gdbarch_pc_regnum (gdbarch), |
| num_regs + MIPS_RA_REGNUM); |
| |
| trad_frame_set_id (this_cache, frame_id_build (sp, func)); |
| } |
| |
| /* A tramp_frame structure describing the stack-based trampoline |
| used on mips-irix. These trampolines are created on the stack |
| before being called. */ |
| |
| static const struct tramp_frame mips_irix_n32_stack_tramp_frame = |
| { |
| SIGTRAMP_FRAME, |
| 4, |
| { |
| { 0x8f210000, 0xffff0000 }, /* lw at, N(t9) */ |
| { 0x8f2f0000, 0xffff0000 }, /* lw t3, M(t9) */ |
| { 0x00200008, 0xffffffff }, /* jr at */ |
| { 0x0020c82d, 0xffffffff }, /* move t9, at */ |
| { TRAMP_SENTINEL_INSN, -1 } |
| }, |
| mips_irix_n32_stack_tramp_frame_init |
| }; |
| |
| static void |
| mips_irix_init_abi (struct gdbarch_info info, |
| struct gdbarch *gdbarch) |
| { |
| set_solib_ops (gdbarch, &irix_so_ops); |
| tramp_frame_prepend_unwinder (gdbarch, &mips_irix_n32_stack_tramp_frame); |
| tramp_frame_prepend_unwinder (gdbarch, &mips_irix_n32_tramp_frame); |
| } |
| |
| /* Provide a prototype to silence -Wmissing-prototypes. */ |
| extern initialize_file_ftype _initialize_mips_irix_tdep; |
| |
| void |
| _initialize_mips_irix_tdep (void) |
| { |
| /* Register an ELF OS ABI sniffer for IRIX binaries. */ |
| gdbarch_register_osabi_sniffer (bfd_arch_mips, |
| bfd_target_elf_flavour, |
| mips_irix_elf_osabi_sniffer); |
| |
| gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_IRIX, |
| mips_irix_init_abi); |
| } |
