1# Source (tiny.cc): 2# void a() {} 3# void b() {} 4# int main(int argc, char** argv) { 5# void(*ptr)(); 6# if (argc == 1) 7# ptr = &a; 8# else 9# ptr = &b; 10# ptr(); 11# } 12# Compile with: 13# clang++ -g tiny.cc -S -o tiny.s 14 15 .text 16 .file "tiny.cc" 17 .globl _Z1av # -- Begin function _Z1av 18 .p2align 4, 0x90 19 .type _Z1av,@function 20_Z1av: # @_Z1av 21.Lfunc_begin0: 22 .file 1 "tiny.cc" 23 .loc 1 1 0 # tiny.cc:1:0 24 .cfi_startproc 25# %bb.0: 26 pushq %rbp 27 .cfi_def_cfa_offset 16 28 .cfi_offset %rbp, -16 29 movq %rsp, %rbp 30 .cfi_def_cfa_register %rbp 31.Ltmp0: 32 .loc 1 1 11 prologue_end # tiny.cc:1:11 33 popq %rbp 34 .cfi_def_cfa %rsp, 8 35 retq 36.Ltmp1: 37.Lfunc_end0: 38 .size _Z1av, .Lfunc_end0-_Z1av 39 .cfi_endproc 40 # -- End function 41 .globl _Z1bv # -- Begin function _Z1bv 42 .p2align 4, 0x90 43 .type _Z1bv,@function 44_Z1bv: # @_Z1bv 45.Lfunc_begin1: 46 .loc 1 2 0 # tiny.cc:2:0 47 .cfi_startproc 48# %bb.0: 49 pushq %rbp 50 .cfi_def_cfa_offset 16 51 .cfi_offset %rbp, -16 52 movq %rsp, %rbp 53 .cfi_def_cfa_register %rbp 54.Ltmp2: 55 .loc 1 2 11 prologue_end # tiny.cc:2:11 56 popq %rbp 57 .cfi_def_cfa %rsp, 8 58 retq 59.Ltmp3: 60.Lfunc_end1: 61 .size _Z1bv, .Lfunc_end1-_Z1bv 62 .cfi_endproc 63 # -- End function 64 .globl main # -- Begin function main 65 .p2align 4, 0x90 66 .type main,@function 67main: # @main 68.Lfunc_begin2: 69 .loc 1 4 0 # tiny.cc:4:0 70 .cfi_startproc 71# %bb.0: 72 pushq %rbp 73 .cfi_def_cfa_offset 16 74 .cfi_offset %rbp, -16 75 movq %rsp, %rbp 76 .cfi_def_cfa_register %rbp 77 subq $32, %rsp 78 movl $0, -4(%rbp) 79 movl %edi, -8(%rbp) 80 movq %rsi, -16(%rbp) 81.Ltmp4: 82 .loc 1 6 12 prologue_end # tiny.cc:6:12 83 cmpl $1, -8(%rbp) 84.Ltmp5: 85 .loc 1 6 7 is_stmt 0 # tiny.cc:6:7 86 jne .LBB2_2 87# %bb.1: 88 .loc 1 0 7 # tiny.cc:0:7 89 movabsq $_Z1av, %rax 90.Ltmp6: 91 .loc 1 7 9 is_stmt 1 # tiny.cc:7:9 92 movq %rax, -24(%rbp) 93 .loc 1 7 5 is_stmt 0 # tiny.cc:7:5 94 jmp .LBB2_3 95.LBB2_2: 96 .loc 1 0 5 # tiny.cc:0:5 97 movabsq $_Z1bv, %rax 98 .loc 1 9 9 is_stmt 1 # tiny.cc:9:9 99 movq %rax, -24(%rbp) 100.Ltmp7: 101.LBB2_3: 102 .loc 1 11 3 # tiny.cc:11:3 103 callq *-24(%rbp) 104 .loc 1 12 1 # tiny.cc:12:1 105 movl -4(%rbp), %eax 106 addq $32, %rsp 107 popq %rbp 108 .cfi_def_cfa %rsp, 8 109 retq 110.Ltmp8: 111.Lfunc_end2: 112 .size main, .Lfunc_end2-main 113 .cfi_endproc 114 # -- End function 115 .section .debug_str,"MS",@progbits,1 116.Linfo_string0: 117 .asciz "clang version 6.0.0 (trunk 317104)" # string offset=0 118.Linfo_string1: 119 .asciz "tiny.cc" # string offset=35 120.Linfo_string2: 121 .asciz "/tmp/a/b" # string offset=43 122.Linfo_string3: 123 .asciz "_Z1av" # string offset=52 124.Linfo_string4: 125 .asciz "a" # string offset=58 126.Linfo_string5: 127 .asciz "_Z1bv" # string offset=60 128.Linfo_string6: 129 .asciz "b" # string offset=66 130.Linfo_string7: 131 .asciz "main" # string offset=68 132.Linfo_string8: 133 .asciz "int" # string offset=73 134.Linfo_string9: 135 .asciz "argc" # string offset=77 136.Linfo_string10: 137 .asciz "argv" # string offset=82 138.Linfo_string11: 139 .asciz "char" # string offset=87 140.Linfo_string12: 141 .asciz "ptr" # string offset=92 142 .section .debug_abbrev,"",@progbits 143 .byte 1 # Abbreviation Code 144 .byte 17 # DW_TAG_compile_unit 145 .byte 1 # DW_CHILDREN_yes 146 .byte 37 # DW_AT_producer 147 .byte 14 # DW_FORM_strp 148 .byte 19 # DW_AT_language 149 .byte 5 # DW_FORM_data2 150 .byte 3 # DW_AT_name 151 .byte 14 # DW_FORM_strp 152 .byte 16 # DW_AT_stmt_list 153 .byte 23 # DW_FORM_sec_offset 154 .byte 27 # DW_AT_comp_dir 155 .byte 14 # DW_FORM_strp 156 .ascii "\264B" # DW_AT_GNU_pubnames 157 .byte 25 # DW_FORM_flag_present 158 .byte 17 # DW_AT_low_pc 159 .byte 1 # DW_FORM_addr 160 .byte 18 # DW_AT_high_pc 161 .byte 6 # DW_FORM_data4 162 .byte 0 # EOM(1) 163 .byte 0 # EOM(2) 164 .byte 2 # Abbreviation Code 165 .byte 46 # DW_TAG_subprogram 166 .byte 0 # DW_CHILDREN_no 167 .byte 17 # DW_AT_low_pc 168 .byte 1 # DW_FORM_addr 169 .byte 18 # DW_AT_high_pc 170 .byte 6 # DW_FORM_data4 171 .byte 64 # DW_AT_frame_base 172 .byte 24 # DW_FORM_exprloc 173 .byte 110 # DW_AT_linkage_name 174 .byte 14 # DW_FORM_strp 175 .byte 3 # DW_AT_name 176 .byte 14 # DW_FORM_strp 177 .byte 58 # DW_AT_decl_file 178 .byte 11 # DW_FORM_data1 179 .byte 59 # DW_AT_decl_line 180 .byte 11 # DW_FORM_data1 181 .byte 63 # DW_AT_external 182 .byte 25 # DW_FORM_flag_present 183 .byte 0 # EOM(1) 184 .byte 0 # EOM(2) 185 .byte 3 # Abbreviation Code 186 .byte 46 # DW_TAG_subprogram 187 .byte 1 # DW_CHILDREN_yes 188 .byte 17 # DW_AT_low_pc 189 .byte 1 # DW_FORM_addr 190 .byte 18 # DW_AT_high_pc 191 .byte 6 # DW_FORM_data4 192 .byte 64 # DW_AT_frame_base 193 .byte 24 # DW_FORM_exprloc 194 .byte 3 # DW_AT_name 195 .byte 14 # DW_FORM_strp 196 .byte 58 # DW_AT_decl_file 197 .byte 11 # DW_FORM_data1 198 .byte 59 # DW_AT_decl_line 199 .byte 11 # DW_FORM_data1 200 .byte 73 # DW_AT_type 201 .byte 19 # DW_FORM_ref4 202 .byte 63 # DW_AT_external 203 .byte 25 # DW_FORM_flag_present 204 .byte 0 # EOM(1) 205 .byte 0 # EOM(2) 206 .byte 4 # Abbreviation Code 207 .byte 5 # DW_TAG_formal_parameter 208 .byte 0 # DW_CHILDREN_no 209 .byte 2 # DW_AT_location 210 .byte 24 # DW_FORM_exprloc 211 .byte 3 # DW_AT_name 212 .byte 14 # DW_FORM_strp 213 .byte 58 # DW_AT_decl_file 214 .byte 11 # DW_FORM_data1 215 .byte 59 # DW_AT_decl_line 216 .byte 11 # DW_FORM_data1 217 .byte 73 # DW_AT_type 218 .byte 19 # DW_FORM_ref4 219 .byte 0 # EOM(1) 220 .byte 0 # EOM(2) 221 .byte 5 # Abbreviation Code 222 .byte 52 # DW_TAG_variable 223 .byte 0 # DW_CHILDREN_no 224 .byte 2 # DW_AT_location 225 .byte 24 # DW_FORM_exprloc 226 .byte 3 # DW_AT_name 227 .byte 14 # DW_FORM_strp 228 .byte 58 # DW_AT_decl_file 229 .byte 11 # DW_FORM_data1 230 .byte 59 # DW_AT_decl_line 231 .byte 11 # DW_FORM_data1 232 .byte 73 # DW_AT_type 233 .byte 19 # DW_FORM_ref4 234 .byte 0 # EOM(1) 235 .byte 0 # EOM(2) 236 .byte 6 # Abbreviation Code 237 .byte 36 # DW_TAG_base_type 238 .byte 0 # DW_CHILDREN_no 239 .byte 3 # DW_AT_name 240 .byte 14 # DW_FORM_strp 241 .byte 62 # DW_AT_encoding 242 .byte 11 # DW_FORM_data1 243 .byte 11 # DW_AT_byte_size 244 .byte 11 # DW_FORM_data1 245 .byte 0 # EOM(1) 246 .byte 0 # EOM(2) 247 .byte 7 # Abbreviation Code 248 .byte 15 # DW_TAG_pointer_type 249 .byte 0 # DW_CHILDREN_no 250 .byte 73 # DW_AT_type 251 .byte 19 # DW_FORM_ref4 252 .byte 0 # EOM(1) 253 .byte 0 # EOM(2) 254 .byte 8 # Abbreviation Code 255 .byte 21 # DW_TAG_subroutine_type 256 .byte 0 # DW_CHILDREN_no 257 .byte 0 # EOM(1) 258 .byte 0 # EOM(2) 259 .byte 0 # EOM(3) 260 .section .debug_info,"",@progbits 261.Lcu_begin0: 262 .long 187 # Length of Unit 263 .short 4 # DWARF version number 264 .long .debug_abbrev # Offset Into Abbrev. Section 265 .byte 8 # Address Size (in bytes) 266 .byte 1 # Abbrev [1] 0xb:0xb4 DW_TAG_compile_unit 267 .long .Linfo_string0 # DW_AT_producer 268 .short 4 # DW_AT_language 269 .long .Linfo_string1 # DW_AT_name 270 .long .Lline_table_start0 # DW_AT_stmt_list 271 .long .Linfo_string2 # DW_AT_comp_dir 272 # DW_AT_GNU_pubnames 273 .quad .Lfunc_begin0 # DW_AT_low_pc 274 .long .Lfunc_end2-.Lfunc_begin0 # DW_AT_high_pc 275 .byte 2 # Abbrev [2] 0x2a:0x19 DW_TAG_subprogram 276 .quad .Lfunc_begin0 # DW_AT_low_pc 277 .long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc 278 .byte 1 # DW_AT_frame_base 279 .byte 86 280 .long .Linfo_string3 # DW_AT_linkage_name 281 .long .Linfo_string4 # DW_AT_name 282 .byte 1 # DW_AT_decl_file 283 .byte 1 # DW_AT_decl_line 284 # DW_AT_external 285 .byte 2 # Abbrev [2] 0x43:0x19 DW_TAG_subprogram 286 .quad .Lfunc_begin1 # DW_AT_low_pc 287 .long .Lfunc_end1-.Lfunc_begin1 # DW_AT_high_pc 288 .byte 1 # DW_AT_frame_base 289 .byte 86 290 .long .Linfo_string5 # DW_AT_linkage_name 291 .long .Linfo_string6 # DW_AT_name 292 .byte 1 # DW_AT_decl_file 293 .byte 2 # DW_AT_decl_line 294 # DW_AT_external 295 .byte 3 # Abbrev [3] 0x5c:0x44 DW_TAG_subprogram 296 .quad .Lfunc_begin2 # DW_AT_low_pc 297 .long .Lfunc_end2-.Lfunc_begin2 # DW_AT_high_pc 298 .byte 1 # DW_AT_frame_base 299 .byte 86 300 .long .Linfo_string7 # DW_AT_name 301 .byte 1 # DW_AT_decl_file 302 .byte 4 # DW_AT_decl_line 303 .long 160 # DW_AT_type 304 # DW_AT_external 305 .byte 4 # Abbrev [4] 0x75:0xe DW_TAG_formal_parameter 306 .byte 2 # DW_AT_location 307 .byte 145 308 .byte 120 309 .long .Linfo_string9 # DW_AT_name 310 .byte 1 # DW_AT_decl_file 311 .byte 4 # DW_AT_decl_line 312 .long 160 # DW_AT_type 313 .byte 4 # Abbrev [4] 0x83:0xe DW_TAG_formal_parameter 314 .byte 2 # DW_AT_location 315 .byte 145 316 .byte 112 317 .long .Linfo_string10 # DW_AT_name 318 .byte 1 # DW_AT_decl_file 319 .byte 4 # DW_AT_decl_line 320 .long 167 # DW_AT_type 321 .byte 5 # Abbrev [5] 0x91:0xe DW_TAG_variable 322 .byte 2 # DW_AT_location 323 .byte 145 324 .byte 104 325 .long .Linfo_string12 # DW_AT_name 326 .byte 1 # DW_AT_decl_file 327 .byte 5 # DW_AT_decl_line 328 .long 184 # DW_AT_type 329 .byte 0 # End Of Children Mark 330 .byte 6 # Abbrev [6] 0xa0:0x7 DW_TAG_base_type 331 .long .Linfo_string8 # DW_AT_name 332 .byte 5 # DW_AT_encoding 333 .byte 4 # DW_AT_byte_size 334 .byte 7 # Abbrev [7] 0xa7:0x5 DW_TAG_pointer_type 335 .long 172 # DW_AT_type 336 .byte 7 # Abbrev [7] 0xac:0x5 DW_TAG_pointer_type 337 .long 177 # DW_AT_type 338 .byte 6 # Abbrev [6] 0xb1:0x7 DW_TAG_base_type 339 .long .Linfo_string11 # DW_AT_name 340 .byte 6 # DW_AT_encoding 341 .byte 1 # DW_AT_byte_size 342 .byte 7 # Abbrev [7] 0xb8:0x5 DW_TAG_pointer_type 343 .long 189 # DW_AT_type 344 .byte 8 # Abbrev [8] 0xbd:0x1 DW_TAG_subroutine_type 345 .byte 0 # End Of Children Mark 346 .section .debug_ranges,"",@progbits 347 .section .debug_macinfo,"",@progbits 348.Lcu_macro_begin0: 349 .byte 0 # End Of Macro List Mark 350 .section .debug_pubnames,"",@progbits 351 .long .LpubNames_end0-.LpubNames_begin0 # Length of Public Names Info 352.LpubNames_begin0: 353 .short 2 # DWARF Version 354 .long .Lcu_begin0 # Offset of Compilation Unit Info 355 .long 191 # Compilation Unit Length 356 .long 42 # DIE offset 357 .asciz "a" # External Name 358 .long 67 # DIE offset 359 .asciz "b" # External Name 360 .long 92 # DIE offset 361 .asciz "main" # External Name 362 .long 0 # End Mark 363.LpubNames_end0: 364 .section .debug_pubtypes,"",@progbits 365 .long .LpubTypes_end0-.LpubTypes_begin0 # Length of Public Types Info 366.LpubTypes_begin0: 367 .short 2 # DWARF Version 368 .long .Lcu_begin0 # Offset of Compilation Unit Info 369 .long 191 # Compilation Unit Length 370 .long 160 # DIE offset 371 .asciz "int" # External Name 372 .long 177 # DIE offset 373 .asciz "char" # External Name 374 .long 0 # End Mark 375.LpubTypes_end0: 376 377 .ident "clang version 6.0.0 (trunk 317104)" 378 .section ".note.GNU-stack","",@progbits 379 .section .debug_line,"",@progbits 380.Lline_table_start0: 381