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| # Source (tiny.cc):
# void a() {}
# void b() {}
# int main(int argc, char** argv) {
# void(*ptr)();
# if (argc == 1)
# ptr = &a;
# else
# ptr = &b;
# ptr();
# }
# Compile with:
# clang++ -g tiny.cc -S -o tiny.s
.text
.file "tiny.cc"
.globl _Z1av # -- Begin function _Z1av
.p2align 4, 0x90
.type _Z1av,@function
_Z1av: # @_Z1av
.Lfunc_begin0:
.file 1 "tiny.cc"
.loc 1 1 0 # tiny.cc:1:0
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
.Ltmp0:
.loc 1 1 11 prologue_end # tiny.cc:1:11
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Ltmp1:
.Lfunc_end0:
.size _Z1av, .Lfunc_end0-_Z1av
.cfi_endproc
# -- End function
.globl _Z1bv # -- Begin function _Z1bv
.p2align 4, 0x90
.type _Z1bv,@function
_Z1bv: # @_Z1bv
.Lfunc_begin1:
.loc 1 2 0 # tiny.cc:2:0
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
.Ltmp2:
.loc 1 2 11 prologue_end # tiny.cc:2:11
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Ltmp3:
.Lfunc_end1:
.size _Z1bv, .Lfunc_end1-_Z1bv
.cfi_endproc
# -- End function
.globl main # -- Begin function main
.p2align 4, 0x90
.type main,@function
main: # @main
.Lfunc_begin2:
.loc 1 4 0 # tiny.cc:4:0
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
subq $32, %rsp
movl $0, -4(%rbp)
movl %edi, -8(%rbp)
movq %rsi, -16(%rbp)
.Ltmp4:
.loc 1 6 12 prologue_end # tiny.cc:6:12
cmpl $1, -8(%rbp)
.Ltmp5:
.loc 1 6 7 is_stmt 0 # tiny.cc:6:7
jne .LBB2_2
# %bb.1:
.loc 1 0 7 # tiny.cc:0:7
movabsq $_Z1av, %rax
.Ltmp6:
.loc 1 7 9 is_stmt 1 # tiny.cc:7:9
movq %rax, -24(%rbp)
.loc 1 7 5 is_stmt 0 # tiny.cc:7:5
jmp .LBB2_3
.LBB2_2:
.loc 1 0 5 # tiny.cc:0:5
movabsq $_Z1bv, %rax
.loc 1 9 9 is_stmt 1 # tiny.cc:9:9
movq %rax, -24(%rbp)
.Ltmp7:
.LBB2_3:
.loc 1 11 3 # tiny.cc:11:3
callq *-24(%rbp)
.loc 1 12 1 # tiny.cc:12:1
movl -4(%rbp), %eax
addq $32, %rsp
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Ltmp8:
.Lfunc_end2:
.size main, .Lfunc_end2-main
.cfi_endproc
# -- End function
.section .debug_str,"MS",@progbits,1
.Linfo_string0:
.asciz "clang version 6.0.0 (trunk 317104)" # string offset=0
.Linfo_string1:
.asciz "tiny.cc" # string offset=35
.Linfo_string2:
.asciz "/tmp/a/b" # string offset=43
.Linfo_string3:
.asciz "_Z1av" # string offset=52
.Linfo_string4:
.asciz "a" # string offset=58
.Linfo_string5:
.asciz "_Z1bv" # string offset=60
.Linfo_string6:
.asciz "b" # string offset=66
.Linfo_string7:
.asciz "main" # string offset=68
.Linfo_string8:
.asciz "int" # string offset=73
.Linfo_string9:
.asciz "argc" # string offset=77
.Linfo_string10:
.asciz "argv" # string offset=82
.Linfo_string11:
.asciz "char" # string offset=87
.Linfo_string12:
.asciz "ptr" # string offset=92
.section .debug_abbrev,"",@progbits
.byte 1 # Abbreviation Code
.byte 17 # DW_TAG_compile_unit
.byte 1 # DW_CHILDREN_yes
.byte 37 # DW_AT_producer
.byte 14 # DW_FORM_strp
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 16 # DW_AT_stmt_list
.byte 23 # DW_FORM_sec_offset
.byte 27 # DW_AT_comp_dir
.byte 14 # DW_FORM_strp
.ascii "\264B" # DW_AT_GNU_pubnames
.byte 25 # DW_FORM_flag_present
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 2 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 64 # DW_AT_frame_base
.byte 24 # DW_FORM_exprloc
.byte 110 # DW_AT_linkage_name
.byte 14 # DW_FORM_strp
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 63 # DW_AT_external
.byte 25 # DW_FORM_flag_present
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 64 # DW_AT_frame_base
.byte 24 # DW_FORM_exprloc
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 63 # DW_AT_external
.byte 25 # DW_FORM_flag_present
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 4 # Abbreviation Code
.byte 5 # DW_TAG_formal_parameter
.byte 0 # DW_CHILDREN_no
.byte 2 # DW_AT_location
.byte 24 # DW_FORM_exprloc
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 5 # Abbreviation Code
.byte 52 # DW_TAG_variable
.byte 0 # DW_CHILDREN_no
.byte 2 # DW_AT_location
.byte 24 # DW_FORM_exprloc
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 6 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 62 # DW_AT_encoding
.byte 11 # DW_FORM_data1
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 7 # Abbreviation Code
.byte 15 # DW_TAG_pointer_type
.byte 0 # DW_CHILDREN_no
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 8 # Abbreviation Code
.byte 21 # DW_TAG_subroutine_type
.byte 0 # DW_CHILDREN_no
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 0 # EOM(3)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long 187 # Length of Unit
.short 4 # DWARF version number
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 8 # Address Size (in bytes)
.byte 1 # Abbrev [1] 0xb:0xb4 DW_TAG_compile_unit
.long .Linfo_string0 # DW_AT_producer
.short 4 # DW_AT_language
.long .Linfo_string1 # DW_AT_name
.long .Lline_table_start0 # DW_AT_stmt_list
.long .Linfo_string2 # DW_AT_comp_dir
# DW_AT_GNU_pubnames
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end2-.Lfunc_begin0 # DW_AT_high_pc
.byte 2 # Abbrev [2] 0x2a:0x19 DW_TAG_subprogram
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.long .Linfo_string3 # DW_AT_linkage_name
.long .Linfo_string4 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 1 # DW_AT_decl_line
# DW_AT_external
.byte 2 # Abbrev [2] 0x43:0x19 DW_TAG_subprogram
.quad .Lfunc_begin1 # DW_AT_low_pc
.long .Lfunc_end1-.Lfunc_begin1 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.long .Linfo_string5 # DW_AT_linkage_name
.long .Linfo_string6 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 2 # DW_AT_decl_line
# DW_AT_external
.byte 3 # Abbrev [3] 0x5c:0x44 DW_TAG_subprogram
.quad .Lfunc_begin2 # DW_AT_low_pc
.long .Lfunc_end2-.Lfunc_begin2 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.long .Linfo_string7 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 4 # DW_AT_decl_line
.long 160 # DW_AT_type
# DW_AT_external
.byte 4 # Abbrev [4] 0x75:0xe DW_TAG_formal_parameter
.byte 2 # DW_AT_location
.byte 145
.byte 120
.long .Linfo_string9 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 4 # DW_AT_decl_line
.long 160 # DW_AT_type
.byte 4 # Abbrev [4] 0x83:0xe DW_TAG_formal_parameter
.byte 2 # DW_AT_location
.byte 145
.byte 112
.long .Linfo_string10 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 4 # DW_AT_decl_line
.long 167 # DW_AT_type
.byte 5 # Abbrev [5] 0x91:0xe DW_TAG_variable
.byte 2 # DW_AT_location
.byte 145
.byte 104
.long .Linfo_string12 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 5 # DW_AT_decl_line
.long 184 # DW_AT_type
.byte 0 # End Of Children Mark
.byte 6 # Abbrev [6] 0xa0:0x7 DW_TAG_base_type
.long .Linfo_string8 # DW_AT_name
.byte 5 # DW_AT_encoding
.byte 4 # DW_AT_byte_size
.byte 7 # Abbrev [7] 0xa7:0x5 DW_TAG_pointer_type
.long 172 # DW_AT_type
.byte 7 # Abbrev [7] 0xac:0x5 DW_TAG_pointer_type
.long 177 # DW_AT_type
.byte 6 # Abbrev [6] 0xb1:0x7 DW_TAG_base_type
.long .Linfo_string11 # DW_AT_name
.byte 6 # DW_AT_encoding
.byte 1 # DW_AT_byte_size
.byte 7 # Abbrev [7] 0xb8:0x5 DW_TAG_pointer_type
.long 189 # DW_AT_type
.byte 8 # Abbrev [8] 0xbd:0x1 DW_TAG_subroutine_type
.byte 0 # End Of Children Mark
.section .debug_ranges,"",@progbits
.section .debug_macinfo,"",@progbits
.Lcu_macro_begin0:
.byte 0 # End Of Macro List Mark
.section .debug_pubnames,"",@progbits
.long .LpubNames_end0-.LpubNames_begin0 # Length of Public Names Info
.LpubNames_begin0:
.short 2 # DWARF Version
.long .Lcu_begin0 # Offset of Compilation Unit Info
.long 191 # Compilation Unit Length
.long 42 # DIE offset
.asciz "a" # External Name
.long 67 # DIE offset
.asciz "b" # External Name
.long 92 # DIE offset
.asciz "main" # External Name
.long 0 # End Mark
.LpubNames_end0:
.section .debug_pubtypes,"",@progbits
.long .LpubTypes_end0-.LpubTypes_begin0 # Length of Public Types Info
.LpubTypes_begin0:
.short 2 # DWARF Version
.long .Lcu_begin0 # Offset of Compilation Unit Info
.long 191 # Compilation Unit Length
.long 160 # DIE offset
.asciz "int" # External Name
.long 177 # DIE offset
.asciz "char" # External Name
.long 0 # End Mark
.LpubTypes_end0:
.ident "clang version 6.0.0 (trunk 317104)"
.section ".note.GNU-stack","",@progbits
.section .debug_line,"",@progbits
.Lline_table_start0:
|