| /* Darwin support for GDB, the GNU debugger. |
| Copyright 1997-2002, 2005, 2008-2012 Free Software Foundation, Inc. |
| |
| Contributed by Apple Computer, 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 "frame.h" |
| #include "inferior.h" |
| #include "gdbcore.h" |
| #include "target.h" |
| #include "floatformat.h" |
| #include "symtab.h" |
| #include "regcache.h" |
| #include "libbfd.h" |
| #include "objfiles.h" |
| |
| #include "i387-tdep.h" |
| #include "i386-tdep.h" |
| #include "osabi.h" |
| #include "ui-out.h" |
| #include "symtab.h" |
| #include "frame.h" |
| #include "gdb_assert.h" |
| #include "i386-darwin-tdep.h" |
| #include "solib.h" |
| #include "solib-darwin.h" |
| #include "dwarf2-frame.h" |
| |
| /* Offsets into the struct i386_thread_state where we'll find the saved regs. |
| From <mach/i386/thread_status.h> and i386-tdep.h. */ |
| int i386_darwin_thread_state_reg_offset[] = |
| { |
| 0 * 4, /* EAX */ |
| 2 * 4, /* ECX */ |
| 3 * 4, /* EDX */ |
| 1 * 4, /* EBX */ |
| 7 * 4, /* ESP */ |
| 6 * 4, /* EBP */ |
| 5 * 4, /* ESI */ |
| 4 * 4, /* EDI */ |
| 10 * 4, /* EIP */ |
| 9 * 4, /* EFLAGS */ |
| 11 * 4, /* CS */ |
| 8 * 4, /* SS */ |
| 12 * 4, /* DS */ |
| 13 * 4, /* ES */ |
| 14 * 4, /* FS */ |
| 15 * 4 /* GS */ |
| }; |
| |
| const int i386_darwin_thread_state_num_regs = |
| ARRAY_SIZE (i386_darwin_thread_state_reg_offset); |
| |
| /* Assuming THIS_FRAME is a Darwin sigtramp routine, return the |
| address of the associated sigcontext structure. */ |
| |
| static CORE_ADDR |
| i386_darwin_sigcontext_addr (struct frame_info *this_frame) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| CORE_ADDR bp; |
| CORE_ADDR si; |
| gdb_byte buf[4]; |
| |
| get_frame_register (this_frame, I386_EBP_REGNUM, buf); |
| bp = extract_unsigned_integer (buf, 4, byte_order); |
| |
| /* A pointer to the ucontext is passed as the fourth argument |
| to the signal handler. */ |
| read_memory (bp + 24, buf, 4); |
| si = extract_unsigned_integer (buf, 4, byte_order); |
| |
| /* The pointer to mcontext is at offset 28. */ |
| read_memory (si + 28, buf, 4); |
| |
| /* First register (eax) is at offset 12. */ |
| return extract_unsigned_integer (buf, 4, byte_order) + 12; |
| } |
| |
| /* Return true if the PC of THIS_FRAME is in a signal trampoline which |
| may have DWARF-2 CFI. |
| |
| On Darwin, signal trampolines have DWARF-2 CFI but it has only one FDE |
| that covers only the indirect call to the user handler. |
| Without this function, the frame is recognized as a normal frame which is |
| not expected. */ |
| |
| int |
| darwin_dwarf_signal_frame_p (struct gdbarch *gdbarch, |
| struct frame_info *this_frame) |
| { |
| return i386_sigtramp_p (this_frame); |
| } |
| |
| /* Check wether TYPE is a 128-bit vector (__m128, __m128d or __m128i). */ |
| |
| static int |
| i386_m128_p (struct type *type) |
| { |
| return (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type) |
| && TYPE_LENGTH (type) == 16); |
| } |
| |
| /* Return the alignment for TYPE when passed as an argument. */ |
| |
| static int |
| i386_darwin_arg_type_alignment (struct type *type) |
| { |
| type = check_typedef (type); |
| /* According to Mac OS X ABI document (passing arguments): |
| 6. The caller places 64-bit vectors (__m64) on the parameter area, |
| aligned to 8-byte boundaries. |
| 7. [...] The caller aligns 128-bit vectors in the parameter area to |
| 16-byte boundaries. */ |
| if (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type)) |
| return TYPE_LENGTH (type); |
| /* 4. The caller places all the fields of structures (or unions) with no |
| vector elements in the parameter area. These structures are 4-byte |
| aligned. |
| 5. The caller places structures with vector elements on the stack, |
| 16-byte aligned. */ |
| if (TYPE_CODE (type) == TYPE_CODE_STRUCT |
| || TYPE_CODE (type) == TYPE_CODE_UNION) |
| { |
| int i; |
| int res = 4; |
| for (i = 0; i < TYPE_NFIELDS (type); i++) |
| res = max (res, |
| i386_darwin_arg_type_alignment (TYPE_FIELD_TYPE (type, i))); |
| return res; |
| } |
| /* 2. The caller aligns nonvector arguments to 4-byte boundaries. */ |
| return 4; |
| } |
| |
| static CORE_ADDR |
| i386_darwin_push_dummy_call (struct gdbarch *gdbarch, struct value *function, |
| struct regcache *regcache, CORE_ADDR bp_addr, |
| int nargs, struct value **args, CORE_ADDR sp, |
| int struct_return, CORE_ADDR struct_addr) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| gdb_byte buf[4]; |
| int i; |
| int write_pass; |
| |
| /* Determine the total space required for arguments and struct |
| return address in a first pass, then push arguments in a second pass. */ |
| |
| for (write_pass = 0; write_pass < 2; write_pass++) |
| { |
| int args_space = 0; |
| int num_m128 = 0; |
| |
| if (struct_return) |
| { |
| if (write_pass) |
| { |
| /* Push value address. */ |
| store_unsigned_integer (buf, 4, byte_order, struct_addr); |
| write_memory (sp, buf, 4); |
| } |
| args_space += 4; |
| } |
| |
| for (i = 0; i < nargs; i++) |
| { |
| struct type *arg_type = value_enclosing_type (args[i]); |
| |
| if (i386_m128_p (arg_type) && num_m128 < 4) |
| { |
| if (write_pass) |
| { |
| const gdb_byte *val = value_contents_all (args[i]); |
| regcache_raw_write |
| (regcache, I387_MM0_REGNUM(tdep) + num_m128, val); |
| } |
| num_m128++; |
| } |
| else |
| { |
| int len = TYPE_LENGTH (arg_type); |
| int align = i386_darwin_arg_type_alignment (arg_type); |
| |
| args_space = align_up (args_space, align); |
| if (write_pass) |
| write_memory (sp + args_space, |
| value_contents_all (args[i]), len); |
| |
| /* The System V ABI says that: |
| |
| "An argument's size is increased, if necessary, to make it a |
| multiple of [32-bit] words. This may require tail padding, |
| depending on the size of the argument." |
| |
| This makes sure the stack stays word-aligned. */ |
| args_space += align_up (len, 4); |
| } |
| } |
| |
| /* Darwin i386 ABI: |
| 1. The caller ensures that the stack is 16-byte aligned at the point |
| of the function call. */ |
| if (!write_pass) |
| sp = align_down (sp - args_space, 16); |
| } |
| |
| /* Store return address. */ |
| sp -= 4; |
| store_unsigned_integer (buf, 4, byte_order, bp_addr); |
| write_memory (sp, buf, 4); |
| |
| /* Finally, update the stack pointer... */ |
| store_unsigned_integer (buf, 4, byte_order, sp); |
| regcache_cooked_write (regcache, I386_ESP_REGNUM, buf); |
| |
| /* ...and fake a frame pointer. */ |
| regcache_cooked_write (regcache, I386_EBP_REGNUM, buf); |
| |
| /* MarkK wrote: This "+ 8" is all over the place: |
| (i386_frame_this_id, i386_sigtramp_frame_this_id, |
| i386_dummy_id). It's there, since all frame unwinders for |
| a given target have to agree (within a certain margin) on the |
| definition of the stack address of a frame. Otherwise frame id |
| comparison might not work correctly. Since DWARF2/GCC uses the |
| stack address *before* the function call as a frame's CFA. On |
| the i386, when %ebp is used as a frame pointer, the offset |
| between the contents %ebp and the CFA as defined by GCC. */ |
| return sp + 8; |
| } |
| |
| static void |
| i386_darwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| /* We support the SSE registers. */ |
| tdep->num_xmm_regs = I386_NUM_XREGS - 1; |
| set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS); |
| |
| dwarf2_frame_set_signal_frame_p (gdbarch, darwin_dwarf_signal_frame_p); |
| set_gdbarch_push_dummy_call (gdbarch, i386_darwin_push_dummy_call); |
| |
| tdep->struct_return = reg_struct_return; |
| |
| tdep->sigtramp_p = i386_sigtramp_p; |
| tdep->sigcontext_addr = i386_darwin_sigcontext_addr; |
| tdep->sc_reg_offset = i386_darwin_thread_state_reg_offset; |
| tdep->sc_num_regs = i386_darwin_thread_state_num_regs; |
| |
| tdep->jb_pc_offset = 48; |
| |
| /* Although the i387 extended floating-point has only 80 significant |
| bits, a `long double' actually takes up 128, probably to enforce |
| alignment. */ |
| set_gdbarch_long_double_bit (gdbarch, 128); |
| |
| set_solib_ops (gdbarch, &darwin_so_ops); |
| } |
| |
| static enum gdb_osabi |
| i386_mach_o_osabi_sniffer (bfd *abfd) |
| { |
| if (!bfd_check_format (abfd, bfd_object)) |
| return GDB_OSABI_UNKNOWN; |
| |
| if (bfd_get_arch (abfd) == bfd_arch_i386) |
| return GDB_OSABI_DARWIN; |
| |
| return GDB_OSABI_UNKNOWN; |
| } |
| |
| /* -Wmissing-prototypes */ |
| extern initialize_file_ftype _initialize_i386_darwin_tdep; |
| |
| void |
| _initialize_i386_darwin_tdep (void) |
| { |
| gdbarch_register_osabi_sniffer (bfd_arch_unknown, bfd_target_mach_o_flavour, |
| i386_mach_o_osabi_sniffer); |
| |
| gdbarch_register_osabi (bfd_arch_i386, bfd_mach_i386_i386, |
| GDB_OSABI_DARWIN, i386_darwin_init_abi); |
| } |
