[BOLT][DWARF] Fix handling of multiple DW_OP_addrx in an expression

We were not handling correclty multiple DW_OP_addrx in the location expression.
This was exposed by clang-15 build in release mode with debug information.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D130812

diff --git a/bolt/lib/Rewrite/DWARFRewriter.cpp b/bolt/lib/Rewrite/DWARFRewriter.cpp
index ceb1cdf..35118e8 100644 (file)
--- a/bolt/lib/Rewrite/DWARFRewriter.cpp
+++ b/bolt/lib/Rewrite/DWARFRewriter.cpp
@@ -628,14 +628,19 @@ void DWARFRewriter::updateUnitDebugInfo(
                 Unit.getContext().isLittleEndian(), 0);
             DWARFExpression LocExpr(Data, Unit.getAddressByteSize(),
                                     Unit.getFormParams().Format);
-            uint32_t PrevOffset = 0;
-            constexpr uint32_t SizeOfOpcode = 1;
-            constexpr uint32_t SizeOfForm = 1;
+            uint32_t PrevEndOffset = 0;
+            uint32_t CurrEndOffset = 0;
+            constexpr uint32_t SizeOfOP = 1;
+            constexpr uint32_t SizeOfSizeField = 1;
+            int32_t SizeDiff = 0;
+
+            // Encoding [size of expression] [opcode] [value] [opcode] [value]
             for (auto &Expr : LocExpr) {
+              PrevEndOffset = CurrEndOffset;
+              CurrEndOffset = Expr.getEndOffset();
               if (!(Expr.getCode() == dwarf::DW_OP_GNU_addr_index ||
                     Expr.getCode() == dwarf::DW_OP_addrx))
                 continue;
-
               const uint64_t Index = Expr.getRawOperand(0);
               Optional<object::SectionedAddress> EntryAddress =
                   Unit.getAddrOffsetSectionItem(Index);
@@ -643,29 +648,27 @@ void DWARFRewriter::updateUnitDebugInfo(
               assert(Index <= std::numeric_limits<uint32_t>::max() &&
                      "Invalid Operand Index.");
               if (Expr.getCode() == dwarf::DW_OP_addrx) {
-                const uint32_t EncodingSize =
-                    Expr.getOperandEndOffset(0) - PrevOffset - SizeOfOpcode;
+                const uint32_t EncodingSize = CurrEndOffset - PrevEndOffset - 1;
                 const uint32_t Index = AddrWriter->getIndexFromAddress(
                     EntryAddress->Address, Unit);
                 // Encoding new size.
                 SmallString<8> Tmp;
                 raw_svector_ostream OSE(Tmp);
                 encodeULEB128(Index, OSE);
-                DebugInfoPatcher.addUDataPatch(AttrOffset, Tmp.size() + 1, 1);
-                DebugInfoPatcher.addUDataPatch(AttrOffset + PrevOffset +
-                                                   SizeOfOpcode + SizeOfForm,
+                SizeDiff += Tmp.size() - EncodingSize;
+                DebugInfoPatcher.addUDataPatch(AttrOffset + PrevEndOffset +
+                                                   SizeOfOP + SizeOfSizeField,
                                                Index, EncodingSize);
               } else {
                 // TODO: Re-do this as DWARF5.
                 AddrWriter->addIndexAddress(EntryAddress->Address,
                                             static_cast<uint32_t>(Index), Unit);
               }
-              if (Expr.getDescription().Op[1] ==
-                  DWARFExpression::Operation::SizeNA)
-                PrevOffset = Expr.getOperandEndOffset(0);
-              else
-                PrevOffset = Expr.getOperandEndOffset(1);
             }
+            // Update the size of the experssion.
+            if (SizeDiff)
+              DebugInfoPatcher.addUDataPatch(AttrOffset,
+                                             SizeDiff + CurrEndOffset, 1);
           }
         }
       } else if (Optional<AttrInfo> AttrVal =

diff --git a/bolt/test/X86/dwarf5-multiple-dw-op-addrx-locexpr.s b/bolt/test/X86/dwarf5-multiple-dw-op-addrx-locexpr.s
new file mode 100644 (file)
index 0000000..0b81f80
--- /dev/null
+++ b/bolt/test/X86/dwarf5-multiple-dw-op-addrx-locexpr.s
@@ -0,0 +1,445 @@
+# REQUIRES: system-linux
+
+# RUN: llvm-mc -dwarf-version=5 -filetype=obj -triple x86_64-unknown-linux %s -o %t1.o
+# RUN: %clang %cflags -dwarf-5 %t1.o -o %t.exe -Wl,-q
+# RUN: llvm-bolt %t.exe -o %t.bolt --update-debug-sections
+# RUN: llvm-dwarfdump --show-form --verbose --debug-info %t.exe | FileCheck --check-prefix=PRECHECK %s
+# RUN: llvm-dwarfdump --show-form --verbose --debug-info %t.bolt | FileCheck --check-prefix=CHECK %s
+
+# PRECHECK: DW_TAG_variable
+# PRECHECK: DW_AT_name [DW_FORM_strx1]
+# PRECHECK: DW_AT_type [DW_FORM_ref4]
+# PRECHECK: DW_AT_decl_file [DW_FORM_data1]
+# PRECHECK: DW_AT_decl_line [DW_FORM_data1]
+# PRECHECK: DW_AT_location [DW_FORM_exprloc]  (DW_OP_addrx 0x0, DW_OP_piece 0x4, DW_OP_addrx 0x1, DW_OP_piece 0x4)
+
+
+# CHECK: DW_TAG_variable
+# CHECK: DW_AT_name [DW_FORM_strx1]
+# CHECK: DW_AT_type [DW_FORM_ref4]
+# CHECK: DW_AT_decl_file [DW_FORM_data1]
+# CHECK: DW_AT_decl_line [DW_FORM_data1]
+# CHECK: DW_AT_location [DW_FORM_exprloc]  (DW_OP_addrx 0x4, DW_OP_piece 0x4, DW_OP_addrx 0x5, DW_OP_piece 0x4)
+
+# This test checks that we update DW_AT_location [DW_FORM_exprloc] with multiple DW_OP_addrx.
+
+# struct pair {int i; int j; };
+# static pair p;
+# int load() {
+#     return p.i + p.j;
+# }
+# void store(int i, int j) {
+#     p.i = i;
+#       p.j = j;
+# }
+# int main() {
+# return 0;
+# }
+       .text
+       .file   "main.cpp"
+       .file   0 "task" "main.cpp" md5 0x02662c1bdb2472436fee6b36e4dca0e0
+       .globl  _Z4loadv                        # -- Begin function _Z4loadv
+       .p2align        4, 0x90
+       .type   _Z4loadv,@function
+_Z4loadv:                               # @_Z4loadv
+.Lfunc_begin0:
+       .loc    0 3 0                           # main.cpp:3:0
+       .cfi_startproc
+# %bb.0:                                # %entry
+       .loc    0 4 20 prologue_end             # main.cpp:4:20
+       movl    _ZL1p.1(%rip), %eax
+       .loc    0 4 16 is_stmt 0                # main.cpp:4:16
+       addl    _ZL1p.0(%rip), %eax
+       .loc    0 4 5                           # main.cpp:4:5
+       retq
+.Ltmp0:
+.Lfunc_end0:
+       .size   _Z4loadv, .Lfunc_end0-_Z4loadv
+       .cfi_endproc
+                                        # -- End function
+       .globl  _Z5storeii                      # -- Begin function _Z5storeii
+       .p2align        4, 0x90
+       .type   _Z5storeii,@function
+_Z5storeii:                             # @_Z5storeii
+.Lfunc_begin1:
+       .loc    0 6 0 is_stmt 1                 # main.cpp:6:0
+       .cfi_startproc
+# %bb.0:                                # %entry
+       #DEBUG_VALUE: store:i <- $edi
+       #DEBUG_VALUE: store:j <- $esi
+       .loc    0 7 9 prologue_end              # main.cpp:7:9
+       movl    %edi, _ZL1p.0(%rip)
+       .loc    0 8 11                          # main.cpp:8:11
+       movl    %esi, _ZL1p.1(%rip)
+       .loc    0 9 1                           # main.cpp:9:1
+       retq
+.Ltmp1:
+.Lfunc_end1:
+       .size   _Z5storeii, .Lfunc_end1-_Z5storeii
+       .cfi_endproc
+                                        # -- End function
+       .globl  main                            # -- Begin function main
+       .p2align        4, 0x90
+       .type   main,@function
+main:                                   # @main
+.Lfunc_begin2:
+       .loc    0 10 0                          # main.cpp:10:0
+       .cfi_startproc
+# %bb.0:                                # %entry
+       .loc    0 11 1 prologue_end             # main.cpp:11:1
+       xorl    %eax, %eax
+       retq
+.Ltmp2:
+.Lfunc_end2:
+       .size   main, .Lfunc_end2-main
+       .cfi_endproc
+                                        # -- End function
+       .type   _ZL1p.0,@object                 # @_ZL1p.0
+       .local  _ZL1p.0
+       .comm   _ZL1p.0,4,4
+       .type   _ZL1p.1,@object                 # @_ZL1p.1
+       .local  _ZL1p.1
+       .comm   _ZL1p.1,4,4
+       .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
+       .byte   0                               # EOM(1)
+       .byte   0                               # EOM(2)
+       .byte   2                               # Abbreviation Code
+       .byte   52                              # DW_TAG_variable
+       .byte   0                               # DW_CHILDREN_no
+       .byte   3                               # DW_AT_name
+       .byte   37                              # DW_FORM_strx1
+       .byte   73                              # DW_AT_type
+       .byte   19                              # DW_FORM_ref4
+       .byte   58                              # DW_AT_decl_file
+       .byte   11                              # DW_FORM_data1
+       .byte   59                              # DW_AT_decl_line
+       .byte   11                              # DW_FORM_data1
+       .byte   2                               # DW_AT_location
+       .byte   24                              # DW_FORM_exprloc
+       .byte   110                             # DW_AT_linkage_name
+       .byte   37                              # DW_FORM_strx1
+       .byte   0                               # EOM(1)
+       .byte   0                               # EOM(2)
+       .byte   3                               # Abbreviation Code
+       .byte   19                              # DW_TAG_structure_type
+       .byte   1                               # DW_CHILDREN_yes
+       .byte   54                              # DW_AT_calling_convention
+       .byte   11                              # DW_FORM_data1
+       .byte   3                               # DW_AT_name
+       .byte   37                              # DW_FORM_strx1
+       .byte   11                              # DW_AT_byte_size
+       .byte   11                              # DW_FORM_data1
+       .byte   58                              # DW_AT_decl_file
+       .byte   11                              # DW_FORM_data1
+       .byte   59                              # DW_AT_decl_line
+       .byte   11                              # DW_FORM_data1
+       .byte   0                               # EOM(1)
+       .byte   0                               # EOM(2)
+       .byte   4                               # Abbreviation Code
+       .byte   13                              # DW_TAG_member
+       .byte   0                               # DW_CHILDREN_no
+       .byte   3                               # DW_AT_name
+       .byte   37                              # DW_FORM_strx1
+       .byte   73                              # DW_AT_type
+       .byte   19                              # DW_FORM_ref4
+       .byte   58                              # DW_AT_decl_file
+       .byte   11                              # DW_FORM_data1
+       .byte   59                              # DW_AT_decl_line
+       .byte   11                              # DW_FORM_data1
+       .byte   56                              # DW_AT_data_member_location
+       .byte   11                              # DW_FORM_data1
+       .byte   0                               # EOM(1)
+       .byte   0                               # EOM(2)
+       .byte   5                               # 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   6                               # Abbreviation Code
+       .byte   46                              # DW_TAG_subprogram
+       .byte   0                               # DW_CHILDREN_no
+       .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   110                             # DW_AT_linkage_name
+       .byte   37                              # DW_FORM_strx1
+       .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   63                              # DW_AT_external
+       .byte   25                              # DW_FORM_flag_present
+       .byte   0                               # EOM(1)
+       .byte   0                               # EOM(2)
+       .byte   7                               # 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   110                             # DW_AT_linkage_name
+       .byte   37                              # DW_FORM_strx1
+       .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   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   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   9                               # Abbreviation Code
+       .byte   46                              # DW_TAG_subprogram
+       .byte   0                               # DW_CHILDREN_no
+       .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   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   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:0x87 DW_TAG_compile_unit
+       .byte   0                               # DW_AT_producer
+       .short  33                              # 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   2                               # DW_AT_low_pc
+       .long   .Lfunc_end2-.Lfunc_begin0       # DW_AT_high_pc
+       .long   .Laddr_table_base0              # DW_AT_addr_base
+       .byte   2                               # Abbrev [2] 0x23:0x12 DW_TAG_variable
+       .byte   3                               # DW_AT_name
+       .long   53                              # DW_AT_type
+       .byte   0                               # DW_AT_decl_file
+       .byte   2                               # DW_AT_decl_line
+       .byte   8                               # DW_AT_location
+       .byte   161
+       .byte   0
+       .byte   147
+       .byte   4
+       .byte   161
+       .byte   1
+       .byte   147
+       .byte   4
+       .byte   8                               # DW_AT_linkage_name
+       .byte   3                               # Abbrev [3] 0x35:0x19 DW_TAG_structure_type
+       .byte   5                               # DW_AT_calling_convention
+       .byte   7                               # DW_AT_name
+       .byte   8                               # DW_AT_byte_size
+       .byte   0                               # DW_AT_decl_file
+       .byte   1                               # DW_AT_decl_line
+       .byte   4                               # Abbrev [4] 0x3b:0x9 DW_TAG_member
+       .byte   4                               # DW_AT_name
+       .long   78                              # DW_AT_type
+       .byte   0                               # DW_AT_decl_file
+       .byte   1                               # DW_AT_decl_line
+       .byte   0                               # DW_AT_data_member_location
+       .byte   4                               # Abbrev [4] 0x44:0x9 DW_TAG_member
+       .byte   6                               # DW_AT_name
+       .long   78                              # DW_AT_type
+       .byte   0                               # DW_AT_decl_file
+       .byte   1                               # DW_AT_decl_line
+       .byte   4                               # DW_AT_data_member_location
+       .byte   0                               # End Of Children Mark
+       .byte   5                               # Abbrev [5] 0x4e:0x4 DW_TAG_base_type
+       .byte   5                               # DW_AT_name
+       .byte   5                               # DW_AT_encoding
+       .byte   4                               # DW_AT_byte_size
+       .byte   6                               # Abbrev [6] 0x52:0x10 DW_TAG_subprogram
+       .byte   2                               # DW_AT_low_pc
+       .long   .Lfunc_end0-.Lfunc_begin0       # DW_AT_high_pc
+       .byte   1                               # DW_AT_frame_base
+       .byte   87
+                                        # DW_AT_call_all_calls
+       .byte   9                               # DW_AT_linkage_name
+       .byte   10                              # DW_AT_name
+       .byte   0                               # DW_AT_decl_file
+       .byte   3                               # DW_AT_decl_line
+       .long   78                              # DW_AT_type
+                                        # DW_AT_external
+       .byte   7                               # Abbrev [7] 0x62:0x21 DW_TAG_subprogram
+       .byte   3                               # DW_AT_low_pc
+       .long   .Lfunc_end1-.Lfunc_begin1       # DW_AT_high_pc
+       .byte   1                               # DW_AT_frame_base
+       .byte   87
+                                        # DW_AT_call_all_calls
+       .byte   11                              # DW_AT_linkage_name
+       .byte   12                              # DW_AT_name
+       .byte   0                               # DW_AT_decl_file
+       .byte   6                               # DW_AT_decl_line
+                                        # DW_AT_external
+       .byte   8                               # Abbrev [8] 0x6e:0xa DW_TAG_formal_parameter
+       .byte   1                               # DW_AT_location
+       .byte   85
+       .byte   4                               # DW_AT_name
+       .byte   0                               # DW_AT_decl_file
+       .byte   6                               # DW_AT_decl_line
+       .long   78                              # DW_AT_type
+       .byte   8                               # Abbrev [8] 0x78:0xa DW_TAG_formal_parameter
+       .byte   1                               # DW_AT_location
+       .byte   84
+       .byte   6                               # DW_AT_name
+       .byte   0                               # DW_AT_decl_file
+       .byte   6                               # DW_AT_decl_line
+       .long   78                              # DW_AT_type
+       .byte   0                               # End Of Children Mark
+       .byte   9                               # Abbrev [9] 0x83:0xf DW_TAG_subprogram
+       .byte   4                               # DW_AT_low_pc
+       .long   .Lfunc_end2-.Lfunc_begin2       # DW_AT_high_pc
+       .byte   1                               # DW_AT_frame_base
+       .byte   87
+                                        # DW_AT_call_all_calls
+       .byte   13                              # DW_AT_name
+       .byte   0                               # DW_AT_decl_file
+       .byte   10                              # DW_AT_decl_line
+       .long   78                              # DW_AT_type
+                                        # DW_AT_external
+       .byte   0                               # End Of Children Mark
+.Ldebug_info_end0:
+       .section        .debug_str_offsets,"",@progbits
+       .long   60                              # Length of String Offsets Set
+       .short  5
+       .short  0
+.Lstr_offsets_base0:
+       .section        .debug_str,"MS",@progbits,1
+.Linfo_string0:
+       .asciz  "clang version 15.0.0" # string offset=0
+.Linfo_string1:
+       .asciz  "main.cpp"                      # string offset=134
+.Linfo_string2:
+       .asciz  "test" # string offset=143
+.Linfo_string3:
+       .asciz  "p"                             # string offset=181
+.Linfo_string4:
+       .asciz  "i"                             # string offset=183
+.Linfo_string5:
+       .asciz  "int"                           # string offset=185
+.Linfo_string6:
+       .asciz  "j"                             # string offset=189
+.Linfo_string7:
+       .asciz  "pair"                          # string offset=191
+.Linfo_string8:
+       .asciz  "_ZL1p"                         # string offset=196
+.Linfo_string9:
+       .asciz  "_Z4loadv"                      # string offset=202
+.Linfo_string10:
+       .asciz  "load"                          # string offset=211
+.Linfo_string11:
+       .asciz  "_Z5storeii"                    # string offset=216
+.Linfo_string12:
+       .asciz  "store"                         # string offset=227
+.Linfo_string13:
+       .asciz  "main"                          # string offset=233
+       .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
+       .long   .Linfo_string9
+       .long   .Linfo_string10
+       .long   .Linfo_string11
+       .long   .Linfo_string12
+       .long   .Linfo_string13
+       .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   _ZL1p.0
+       .quad   _ZL1p.1
+       .quad   .Lfunc_begin0
+       .quad   .Lfunc_begin1
+       .quad   .Lfunc_begin2
+.Ldebug_addr_end0:
+       .ident  "clang version 15.0.0"
+       .section        ".note.GNU-stack","",@progbits
+       .addrsig
+       .section        .debug_line,"",@progbits
+.Lline_table_start0: