| 1 | /* Copyright (C) 2009-2012 Free Software Foundation, Inc. |
| 2 | |
| 3 | This file is part of GDB. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include "defs.h" |
| 19 | #include "osabi.h" |
| 20 | #include "amd64-tdep.h" |
| 21 | #include "solib.h" |
| 22 | #include "solib-target.h" |
| 23 | #include "gdbtypes.h" |
| 24 | #include "gdbcore.h" |
| 25 | #include "regcache.h" |
| 26 | #include "windows-tdep.h" |
| 27 | #include "frame.h" |
| 28 | |
| 29 | /* The registers used to pass integer arguments during a function call. */ |
| 30 | static int amd64_windows_dummy_call_integer_regs[] = |
| 31 | { |
| 32 | AMD64_RCX_REGNUM, /* %rcx */ |
| 33 | AMD64_RDX_REGNUM, /* %rdx */ |
| 34 | 8, /* %r8 */ |
| 35 | 9 /* %r9 */ |
| 36 | }; |
| 37 | |
| 38 | /* Implement the "classify" method in the gdbarch_tdep structure |
| 39 | for amd64-windows. */ |
| 40 | |
| 41 | static void |
| 42 | amd64_windows_classify (struct type *type, enum amd64_reg_class class[2]) |
| 43 | { |
| 44 | switch (TYPE_CODE (type)) |
| 45 | { |
| 46 | case TYPE_CODE_ARRAY: |
| 47 | /* Arrays are always passed by memory. */ |
| 48 | class[0] = class[1] = AMD64_MEMORY; |
| 49 | break; |
| 50 | |
| 51 | case TYPE_CODE_STRUCT: |
| 52 | case TYPE_CODE_UNION: |
| 53 | /* Struct/Union types whose size is 1, 2, 4, or 8 bytes |
| 54 | are passed as if they were integers of the same size. |
| 55 | Types of different sizes are passed by memory. */ |
| 56 | if (TYPE_LENGTH (type) == 1 |
| 57 | || TYPE_LENGTH (type) == 2 |
| 58 | || TYPE_LENGTH (type) == 4 |
| 59 | || TYPE_LENGTH (type) == 8) |
| 60 | { |
| 61 | class[0] = AMD64_INTEGER; |
| 62 | class[1] = AMD64_NO_CLASS; |
| 63 | } |
| 64 | else |
| 65 | class[0] = class[1] = AMD64_MEMORY; |
| 66 | break; |
| 67 | |
| 68 | default: |
| 69 | /* For all the other types, the conventions are the same as |
| 70 | with the System V ABI. */ |
| 71 | amd64_classify (type, class); |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /* Implement the "return_value" gdbarch method for amd64-windows. */ |
| 76 | |
| 77 | static enum return_value_convention |
| 78 | amd64_windows_return_value (struct gdbarch *gdbarch, struct value *function, |
| 79 | struct type *type, struct regcache *regcache, |
| 80 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 81 | { |
| 82 | int len = TYPE_LENGTH (type); |
| 83 | int regnum = -1; |
| 84 | |
| 85 | /* See if our value is returned through a register. If it is, then |
| 86 | store the associated register number in REGNUM. */ |
| 87 | switch (TYPE_CODE (type)) |
| 88 | { |
| 89 | case TYPE_CODE_FLT: |
| 90 | case TYPE_CODE_DECFLOAT: |
| 91 | /* __m128, __m128i, __m128d, floats, and doubles are returned |
| 92 | via XMM0. */ |
| 93 | if (len == 4 || len == 8 || len == 16) |
| 94 | regnum = AMD64_XMM0_REGNUM; |
| 95 | break; |
| 96 | default: |
| 97 | /* All other values that are 1, 2, 4 or 8 bytes long are returned |
| 98 | via RAX. */ |
| 99 | if (len == 1 || len == 2 || len == 4 || len == 8) |
| 100 | regnum = AMD64_RAX_REGNUM; |
| 101 | break; |
| 102 | } |
| 103 | |
| 104 | if (regnum < 0) |
| 105 | { |
| 106 | /* RAX contains the address where the return value has been stored. */ |
| 107 | if (readbuf) |
| 108 | { |
| 109 | ULONGEST addr; |
| 110 | |
| 111 | regcache_raw_read_unsigned (regcache, AMD64_RAX_REGNUM, &addr); |
| 112 | read_memory (addr, readbuf, TYPE_LENGTH (type)); |
| 113 | } |
| 114 | return RETURN_VALUE_ABI_RETURNS_ADDRESS; |
| 115 | } |
| 116 | else |
| 117 | { |
| 118 | /* Extract the return value from the register where it was stored. */ |
| 119 | if (readbuf) |
| 120 | regcache_raw_read_part (regcache, regnum, 0, len, readbuf); |
| 121 | if (writebuf) |
| 122 | regcache_raw_write_part (regcache, regnum, 0, len, writebuf); |
| 123 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | /* Check that the code pointed to by PC corresponds to a call to |
| 128 | __main, skip it if so. Return PC otherwise. */ |
| 129 | |
| 130 | static CORE_ADDR |
| 131 | amd64_skip_main_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 132 | { |
| 133 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 134 | gdb_byte op; |
| 135 | |
| 136 | target_read_memory (pc, &op, 1); |
| 137 | if (op == 0xe8) |
| 138 | { |
| 139 | gdb_byte buf[4]; |
| 140 | |
| 141 | if (target_read_memory (pc + 1, buf, sizeof buf) == 0) |
| 142 | { |
| 143 | struct minimal_symbol *s; |
| 144 | CORE_ADDR call_dest; |
| 145 | |
| 146 | call_dest = pc + 5 + extract_signed_integer (buf, 4, byte_order); |
| 147 | s = lookup_minimal_symbol_by_pc (call_dest); |
| 148 | if (s != NULL |
| 149 | && SYMBOL_LINKAGE_NAME (s) != NULL |
| 150 | && strcmp (SYMBOL_LINKAGE_NAME (s), "__main") == 0) |
| 151 | pc += 5; |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | return pc; |
| 156 | } |
| 157 | |
| 158 | /* Check Win64 DLL jmp trampolines and find jump destination. */ |
| 159 | |
| 160 | static CORE_ADDR |
| 161 | amd64_windows_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) |
| 162 | { |
| 163 | CORE_ADDR destination = 0; |
| 164 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 165 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 166 | |
| 167 | /* Check for jmp *<offset>(%rip) (jump near, absolute indirect (/4)). */ |
| 168 | if (pc && read_memory_unsigned_integer (pc, 2, byte_order) == 0x25ff) |
| 169 | { |
| 170 | /* Get opcode offset and see if we can find a reference in our data. */ |
| 171 | ULONGEST offset |
| 172 | = read_memory_unsigned_integer (pc + 2, 4, byte_order); |
| 173 | |
| 174 | /* Get address of function pointer at end of pc. */ |
| 175 | CORE_ADDR indirect_addr = pc + offset + 6; |
| 176 | |
| 177 | struct minimal_symbol *indsym |
| 178 | = indirect_addr ? lookup_minimal_symbol_by_pc (indirect_addr) : NULL; |
| 179 | const char *symname = indsym ? SYMBOL_LINKAGE_NAME (indsym) : NULL; |
| 180 | |
| 181 | if (symname) |
| 182 | { |
| 183 | if (strncmp (symname, "__imp_", 6) == 0 |
| 184 | || strncmp (symname, "_imp_", 5) == 0) |
| 185 | destination |
| 186 | = read_memory_unsigned_integer (indirect_addr, 8, byte_order); |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | return destination; |
| 191 | } |
| 192 | |
| 193 | static void |
| 194 | amd64_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 195 | { |
| 196 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 197 | |
| 198 | amd64_init_abi (info, gdbarch); |
| 199 | |
| 200 | /* On Windows, "long"s are only 32bit. */ |
| 201 | set_gdbarch_long_bit (gdbarch, 32); |
| 202 | |
| 203 | /* Function calls. */ |
| 204 | tdep->call_dummy_num_integer_regs = |
| 205 | ARRAY_SIZE (amd64_windows_dummy_call_integer_regs); |
| 206 | tdep->call_dummy_integer_regs = amd64_windows_dummy_call_integer_regs; |
| 207 | tdep->classify = amd64_windows_classify; |
| 208 | tdep->memory_args_by_pointer = 1; |
| 209 | tdep->integer_param_regs_saved_in_caller_frame = 1; |
| 210 | set_gdbarch_return_value (gdbarch, amd64_windows_return_value); |
| 211 | set_gdbarch_skip_main_prologue (gdbarch, amd64_skip_main_prologue); |
| 212 | set_gdbarch_skip_trampoline_code (gdbarch, |
| 213 | amd64_windows_skip_trampoline_code); |
| 214 | |
| 215 | set_gdbarch_iterate_over_objfiles_in_search_order |
| 216 | (gdbarch, windows_iterate_over_objfiles_in_search_order); |
| 217 | |
| 218 | set_solib_ops (gdbarch, &solib_target_so_ops); |
| 219 | } |
| 220 | |
| 221 | /* -Wmissing-prototypes */ |
| 222 | extern initialize_file_ftype _initialize_amd64_windows_tdep; |
| 223 | |
| 224 | void |
| 225 | _initialize_amd64_windows_tdep (void) |
| 226 | { |
| 227 | gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, GDB_OSABI_CYGWIN, |
| 228 | amd64_windows_init_abi); |
| 229 | } |
| 230 | |