diff options
Diffstat (limited to 'gdb/i386-darwin-tdep.c')
| -rw-r--r-- | gdb/i386-darwin-tdep.c | 146 |
1 files changed, 145 insertions, 1 deletions
diff --git a/gdb/i386-darwin-tdep.c b/gdb/i386-darwin-tdep.c index 0cd9403..c13788e 100644 --- a/gdb/i386-darwin-tdep.c +++ b/gdb/i386-darwin-tdep.c @@ -109,6 +109,144 @@ darwin_dwarf_signal_frame_p (struct gdbarch *gdbarch, 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) { @@ -119,6 +257,7 @@ i386_darwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) 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; @@ -127,7 +266,12 @@ i386_darwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) tdep->sc_reg_offset = i386_darwin_thread_state_reg_offset; tdep->sc_num_regs = i386_darwin_thread_state_num_regs; - tdep->jb_pc_offset = 20; + 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); } |