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|
/* Original C (for context):
* // Declare a real external call so the compiler must respect ABI clobbers.
* extern int leaf(int) __attribute__((noinline));
*
* __attribute__((noinline))
* int live_across_call(int x) {
* volatile int a = x; // a starts in a GPR (from arg)
* asm volatile("" :: "r"(a)); // keep 'a' live in a register
* int r = leaf(a); // 'a' is live across the call
* asm volatile("" :: "r"(a), "r"(r));// still live afterwards
* return a + r;
* }
*/
.file "live_across_call.c"
.text
.globl live_across_call # -- Begin function live_across_call
.p2align 4
.type live_across_call,@function
live_across_call: # @live_across_call
.Lfunc_begin0:
.file 0 "." "live_across_call.c" md5 0x351c37295026edf0d468774d35f47e5e
.loc 0 5 0 # live_across_call.c:5:0
.cfi_startproc
# %bb.0: # %entry
#DEBUG_VALUE: live_across_call:x <- $edi
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
subq $16, %rsp
.Ltmp0:
.loc 0 6 16 prologue_end # live_across_call.c:6:16
movl %edi, -4(%rbp)
.loc 0 7 26 # live_across_call.c:7:26
movl -4(%rbp), %eax
.loc 0 7 3 is_stmt 0 # live_across_call.c:7:3
#APP
#NO_APP
.loc 0 8 16 is_stmt 1 # live_across_call.c:8:16
movl -4(%rbp), %edi
.Ltmp1:
#DEBUG_VALUE: live_across_call:x <- [DW_OP_LLVM_entry_value 1] $edi
.loc 0 8 11 is_stmt 0 # live_across_call.c:8:11
callq leaf@PLT
.Ltmp2:
#DEBUG_VALUE: live_across_call:r <- $eax
.loc 0 9 26 is_stmt 1 # live_across_call.c:9:26
movl -4(%rbp), %ecx
.loc 0 9 3 is_stmt 0 # live_across_call.c:9:3
#APP
#NO_APP
.loc 0 10 12 is_stmt 1 # live_across_call.c:10:12
addl -4(%rbp), %eax
.Ltmp3:
.loc 0 10 3 epilogue_begin is_stmt 0 # live_across_call.c:10:3
addq $16, %rsp
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Ltmp4:
.Lfunc_end0:
.size live_across_call, .Lfunc_end0-live_across_call
.cfi_endproc
# -- End function
.section .debug_loclists,"",@progbits
.long .Ldebug_list_header_end0-.Ldebug_list_header_start0 # Length
.Ldebug_list_header_start0:
.short 5 # Version
.byte 8 # Address size
.byte 0 # Segment selector size
.long 2 # Offset entry count
.Lloclists_table_base0:
.long .Ldebug_loc0-.Lloclists_table_base0
.long .Ldebug_loc1-.Lloclists_table_base0
.Ldebug_loc0:
.byte 4 # DW_LLE_offset_pair
.uleb128 .Lfunc_begin0-.Lfunc_begin0 # starting offset
.uleb128 .Ltmp1-.Lfunc_begin0 # ending offset
.byte 1 # Loc expr size
.byte 85 # super-register DW_OP_reg5
.byte 4 # DW_LLE_offset_pair
.uleb128 .Ltmp1-.Lfunc_begin0 # starting offset
.uleb128 .Lfunc_end0-.Lfunc_begin0 # ending offset
.byte 4 # Loc expr size
.byte 163 # DW_OP_entry_value
.byte 1 # 1
.byte 85 # super-register DW_OP_reg5
.byte 159 # DW_OP_stack_value
.byte 0 # DW_LLE_end_of_list
.Ldebug_loc1:
.byte 4 # DW_LLE_offset_pair
.uleb128 .Ltmp2-.Lfunc_begin0 # starting offset
.uleb128 .Ltmp3-.Lfunc_begin0 # ending offset
.byte 1 # Loc expr size
.byte 80 # super-register DW_OP_reg0
.byte 0 # DW_LLE_end_of_list
.Ldebug_list_header_end0:
.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 37 # DW_FORM_strx1
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 114 # DW_AT_str_offsets_base
.byte 23 # DW_FORM_sec_offset
.byte 16 # DW_AT_stmt_list
.byte 23 # DW_FORM_sec_offset
.byte 27 # DW_AT_comp_dir
.byte 37 # DW_FORM_strx1
.byte 17 # DW_AT_low_pc
.byte 27 # DW_FORM_addrx
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 115 # DW_AT_addr_base
.byte 23 # DW_FORM_sec_offset
.ascii "\214\001" # DW_AT_loclists_base
.byte 23 # DW_FORM_sec_offset
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 2 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 17 # DW_AT_low_pc
.byte 27 # DW_FORM_addrx
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 64 # DW_AT_frame_base
.byte 24 # DW_FORM_exprloc
.byte 122 # DW_AT_call_all_calls
.byte 25 # DW_FORM_flag_present
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 39 # DW_AT_prototyped
.byte 25 # DW_FORM_flag_present
.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 3 # Abbreviation Code
.byte 5 # DW_TAG_formal_parameter
.byte 0 # DW_CHILDREN_no
.byte 2 # DW_AT_location
.byte 34 # DW_FORM_loclistx
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.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 4 # 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 37 # DW_FORM_strx1
.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 34 # DW_FORM_loclistx
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.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 72 # DW_TAG_call_site
.byte 0 # DW_CHILDREN_no
.byte 127 # DW_AT_call_origin
.byte 19 # DW_FORM_ref4
.byte 125 # DW_AT_call_return_pc
.byte 27 # DW_FORM_addrx
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 7 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 39 # DW_AT_prototyped
.byte 25 # DW_FORM_flag_present
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 60 # DW_AT_declaration
.byte 25 # DW_FORM_flag_present
.byte 63 # DW_AT_external
.byte 25 # DW_FORM_flag_present
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 8 # Abbreviation Code
.byte 5 # DW_TAG_formal_parameter
.byte 0 # DW_CHILDREN_no
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 9 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.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 10 # Abbreviation Code
.byte 53 # DW_TAG_volatile_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 0 # EOM(3)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
.Ldebug_info_start0:
.short 5 # DWARF version number
.byte 1 # DWARF Unit Type
.byte 8 # Address Size (in bytes)
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 1 # Abbrev [1] 0xc:0x66 DW_TAG_compile_unit
.byte 0 # DW_AT_producer
.short 29 # DW_AT_language
.byte 1 # DW_AT_name
.long .Lstr_offsets_base0 # DW_AT_str_offsets_base
.long .Lline_table_start0 # DW_AT_stmt_list
.byte 2 # DW_AT_comp_dir
.byte 0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.long .Laddr_table_base0 # DW_AT_addr_base
.long .Lloclists_table_base0 # DW_AT_loclists_base
.byte 2 # Abbrev [2] 0x27:0x33 DW_TAG_subprogram
.byte 0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
# DW_AT_call_all_calls
.byte 5 # DW_AT_name
.byte 0 # DW_AT_decl_file
.byte 5 # DW_AT_decl_line
# DW_AT_prototyped
.long 104 # DW_AT_type
# DW_AT_external
.byte 3 # Abbrev [3] 0x36:0x9 DW_TAG_formal_parameter
.byte 0 # DW_AT_location
.byte 7 # DW_AT_name
.byte 0 # DW_AT_decl_file
.byte 5 # DW_AT_decl_line
.long 104 # DW_AT_type
.byte 4 # Abbrev [4] 0x3f:0xb DW_TAG_variable
.byte 2 # DW_AT_location
.byte 145
.byte 124
.byte 6 # DW_AT_name
.byte 0 # DW_AT_decl_file
.byte 6 # DW_AT_decl_line
.long 108 # DW_AT_type
.byte 5 # Abbrev [5] 0x4a:0x9 DW_TAG_variable
.byte 1 # DW_AT_location
.byte 8 # DW_AT_name
.byte 0 # DW_AT_decl_file
.byte 8 # DW_AT_decl_line
.long 104 # DW_AT_type
.byte 6 # Abbrev [6] 0x53:0x6 DW_TAG_call_site
.long 90 # DW_AT_call_origin
.byte 1 # DW_AT_call_return_pc
.byte 0 # End Of Children Mark
.byte 7 # Abbrev [7] 0x5a:0xe DW_TAG_subprogram
.byte 3 # DW_AT_name
.byte 0 # DW_AT_decl_file
.byte 2 # DW_AT_decl_line
# DW_AT_prototyped
.long 104 # DW_AT_type
# DW_AT_declaration
# DW_AT_external
.byte 8 # Abbrev [8] 0x62:0x5 DW_TAG_formal_parameter
.long 104 # DW_AT_type
.byte 0 # End Of Children Mark
.byte 9 # Abbrev [9] 0x68:0x4 DW_TAG_base_type
.byte 4 # DW_AT_name
.byte 5 # DW_AT_encoding
.byte 4 # DW_AT_byte_size
.byte 10 # Abbrev [10] 0x6c:0x5 DW_TAG_volatile_type
.long 104 # DW_AT_type
.byte 0 # End Of Children Mark
.Ldebug_info_end0:
.section .debug_str_offsets,"",@progbits
.long 40 # Length of String Offsets Set
.short 5
.short 0
.Lstr_offsets_base0:
.section .debug_str,"MS",@progbits,1
.Linfo_string0:
.asciz "clang version 22.0.0git (https://github.com/UltimateForce21/llvm-project.git 79c0a9e1e7da0f727c41d27c9c6ff8a28bb7d06f)" # string offset=0
.Linfo_string1:
.asciz "live_across_call.c" # string offset=119
.Linfo_string2:
.asciz "." # string offset=138
.Linfo_string3:
.asciz "leaf" # string offset=140
.Linfo_string4:
.asciz "int" # string offset=145
.Linfo_string5:
.asciz "live_across_call" # string offset=149
.Linfo_string6:
.asciz "a" # string offset=166
.Linfo_string7:
.asciz "x" # string offset=168
.Linfo_string8:
.asciz "r" # string offset=170
.section .debug_str_offsets,"",@progbits
.long .Linfo_string0
.long .Linfo_string1
.long .Linfo_string2
.long .Linfo_string3
.long .Linfo_string4
.long .Linfo_string5
.long .Linfo_string6
.long .Linfo_string7
.long .Linfo_string8
.section .debug_addr,"",@progbits
.long .Ldebug_addr_end0-.Ldebug_addr_start0 # Length of contribution
.Ldebug_addr_start0:
.short 5 # DWARF version number
.byte 8 # Address size
.byte 0 # Segment selector size
.Laddr_table_base0:
.quad .Lfunc_begin0
.quad .Ltmp2
.Ldebug_addr_end0:
.ident "clang version 22.0.0git (https://github.com/UltimateForce21/llvm-project.git 79c0a9e1e7da0f727c41d27c9c6ff8a28bb7d06f)"
.section ".note.GNU-stack","",@progbits
.addrsig
.section .debug_line,"",@progbits
.Lline_table_start0:
|
