[llvm-symbolizer][Windows] Add start line when searching in line table sections.

[akhuang]

Summary

Fixes issue where if a line section doesn't start with a line number
then the addresses at the beginning of the section don't have line numbers.

For example, for a line section like this

0001:00000010-00000014, line/column/addr entries = 1
   7 00000013 !

a line number wouldn't be found for addresses from 10 to 12.

This matches behavior when using the DIA SDK.

[rnk]

llvm/test/tools/llvm-symbolizer/pdb/pdb-line-numbers.test

1 ↗

(On Diff #311920)

The input is an object file, not an executable, right? The input should end in .obj, not .exe, in that case.

However, why not make this an assembly test? Check in the generated .s file, which should have .cv_loc directives with line info, and it should be relatively readable.

5 ↗

(On Diff #311920)

This corresponds with the location of the brace, right? I think this will make more sense if you interleave it in a .s file after the corresponding .cv_loc directive with the t.cpp:2:13 location.

[akhuang]

Add assembly test

[akhuang]

Remove other binary test

[rnk]

lgtm

lld/test/COFF/symbolizer-line-numbers.s

+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj %s -o %t.obj -triple x86_64-windows-msvc
+# RUN: lld-link -entry:main -nodefaultlib %t.obj -out:%t.exe -pdb:%t.pdb -debug
+# RUN: llvm-symbolizer --obj=%t.exe --relative-address \
+# RUN:   0x1000 0x1003 0x1010 0x1013 | FileCheck %s
+
+# Compiled from this cpp code:
+# int f1(int x) {
+#   int y = x + 1;
+#   return y;
+# }
+# int f2(int n) {
+#   return f1(n);
+# }
+# int main() {
+#   return f2(100);
+# }
+
+.text
+  .def   @feat.00;
+  .scl  3;
+  .type 0;
+  .endef
+  .globl  @feat.00
+.set @feat.00, 0
+  .file "t.cpp"
+  .def   "?f1@@YAHH@Z";
+  .scl  2;
+  .type 32;
+  .endef
+  .globl  "?f1@@YAHH@Z"                   # -- Begin function ?f1@@YAHH@Z
+  .p2align  4, 0x90
+"?f1@@YAHH@Z":                          # @"?f1@@YAHH@Z"
+.Lfunc_begin0:
+  .cv_func_id 0
+# %bb.0:                                # %entry
+  .cv_file  1 "C:\\src\\tests\\t.cpp" "E6E6D87A9021656AD44E74484F5BA421" 1
+
+# CHECK:      f1(int)
+# CHECK-NEXT: t.cpp:2:13
+  .cv_loc 0 1 2 13                        # t.cpp:2:13
+                                        # kill: def $ecx killed $ecx def $rcx
+  leal  1(%rcx), %eax
+
+# CHECK:      f1(int)
+# CHECK-NEXT: t.cpp:3:3
+  .cv_loc 0 1 3 3                         # t.cpp:3:3
+  retq
+.Ltmp0:
+.Lfunc_end0:
+                                        # -- End function
+  .def   "?f2@@YAHH@Z";
+  .scl  2;
+  .type 32;
+  .endef
+  .globl  "?f2@@YAHH@Z"                   # -- Begin function ?f2@@YAHH@Z
+  .p2align  4, 0x90
+"?f2@@YAHH@Z":                          # @"?f2@@YAHH@Z"
+.Lfunc_begin1:
+  .cv_func_id 1
+# %bb.0:                                # %entry
+# CHECK:      f1
+# CHECK-NEXT: t.cpp:2:0
+# CHECK-NEXT: f2(int)
+# CHECK-NEXT: t.cpp:6:3
+  .cv_inline_site_id 2 within 1 inlined_at 1 6 10
+  .cv_loc 2 1 2 13                        # t.cpp:2:13
+                                        # kill: def $ecx killed $ecx def $rcx
+  leal  1(%rcx), %eax
+.Ltmp1:
+  .cv_loc 1 1 6 3                         # t.cpp:6:3
+  retq
+# CHECK:      f2(int)
+# CHECK-NEXT: t.cpp:6:3
+.Ltmp2:
+.Lfunc_end1:
+                                        # -- End function
+  .def   main;
+  .scl  2;
+  .type 32;
+  .endef
+  .globl  main                            # -- Begin function main
+  .p2align  4, 0x90
+main:                                   # @main
+.Lfunc_begin2:
+  .cv_func_id 3
+# %bb.0:                                # %entry
+  .cv_loc 3 1 9 3                         # t.cpp:9:3
+  movl  $101, %eax
+  retq
+.Ltmp3:
+.Lfunc_end2:
+                                        # -- End function
+  .section  .debug$S,"dr"
+  .p2align  2
+  .long 4                               # Debug section magic
+  .long 241
+  .long .Ltmp5-.Ltmp4                   # Subsection size
+.Ltmp4:
+  .short  .Ltmp7-.Ltmp6                   # Record length
+.Ltmp6:
+  .short  4412                            # Record kind: S_COMPILE3
+  .long 1                               # Flags and language
+  .short  208                             # CPUType
+  .short  12                              # Frontend version
+  .short  0
+  .short  0
+  .short  0
+  .short  12000                           # Backend version
+  .short  0
+  .short  0
+  .short  0
+  .asciz  "clang version 12.0.0 (https://github.com/llvm/llvm-project.git e2e86f4e77ec2fd79743f4d0e94689e9668600ad)" # Null-terminated compiler version string
+  .p2align  2
+.Ltmp7:
+.Ltmp5:
+  .p2align  2
+  .long 246                             # Inlinee lines subsection
+  .long .Ltmp9-.Ltmp8                   # Subsection size
+.Ltmp8:
+  .long 0                               # Inlinee lines signature
+
+                                        # Inlined function f1 starts at t.cpp:1
+  .long 4098                            # Type index of inlined function
+  .cv_filechecksumoffset  1               # Offset into filechecksum table
+  .long 1                               # Starting line number
+.Ltmp9:
+  .p2align  2
+  .long 241                             # Symbol subsection for f1
+  .long .Ltmp11-.Ltmp10                 # Subsection size
+.Ltmp10:
+  .short  .Ltmp13-.Ltmp12                 # Record length
+.Ltmp12:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long .Lfunc_end0-"?f1@@YAHH@Z"       # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4098                            # Function type index
+  .secrel32 "?f1@@YAHH@Z"           # Function section relative address
+  .secidx "?f1@@YAHH@Z"                   # Function section index
+  .byte 0                               # Flags
+  .asciz  "f1"                            # Function name
+  .p2align  2
+.Ltmp13:
+  .short  .Ltmp15-.Ltmp14                 # Record length
+.Ltmp14:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 0                               # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 1048576                         # Flags (defines frame register)
+  .p2align  2
+.Ltmp15:
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+.Ltmp11:
+  .p2align  2
+  .cv_linetable 0, "?f1@@YAHH@Z", .Lfunc_end0
+  .long 241                             # Symbol subsection for f2
+  .long .Ltmp17-.Ltmp16                 # Subsection size
+.Ltmp16:
+  .short  .Ltmp19-.Ltmp18                 # Record length
+.Ltmp18:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long .Lfunc_end1-"?f2@@YAHH@Z"       # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4099                            # Function type index
+  .secrel32 "?f2@@YAHH@Z"           # Function section relative address
+  .secidx "?f2@@YAHH@Z"                   # Function section index
+  .byte 0                               # Flags
+  .asciz  "f2"                            # Function name
+  .p2align  2
+.Ltmp19:
+  .short  .Ltmp21-.Ltmp20                 # Record length
+.Ltmp20:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 0                               # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 1048576                         # Flags (defines frame register)
+  .p2align  2
+.Ltmp21:
+  .short  .Ltmp23-.Ltmp22                 # Record length
+.Ltmp22:
+  .short  4429                            # Record kind: S_INLINESITE
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 4098                            # Inlinee type index
+  .cv_inline_linetable  2 1 1 .Lfunc_begin1 .Lfunc_end1
+  .p2align  2
+.Ltmp23:
+  .short  2                               # Record length
+  .short  4430                            # Record kind: S_INLINESITE_END
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+.Ltmp17:
+  .p2align  2
+  .cv_linetable 1, "?f2@@YAHH@Z", .Lfunc_end1
+  .long 241                             # Symbol subsection for main
+  .long .Ltmp25-.Ltmp24                 # Subsection size
+.Ltmp24:
+  .short  .Ltmp27-.Ltmp26                 # Record length
+.Ltmp26:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long .Lfunc_end2-main                # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4100                            # Function type index
+  .secrel32 main                    # Function section relative address
+  .secidx main                            # Function section index
+  .byte 0                               # Flags
+  .asciz  "main"                          # Function name
+  .p2align  2
+.Ltmp27:
+  .short  .Ltmp29-.Ltmp28                 # Record length
+.Ltmp28:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 0                               # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 1048576                         # Flags (defines frame register)
+  .p2align  2
+.Ltmp29:
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+.Ltmp25:
+  .p2align  2
+  .cv_linetable 3, main, .Lfunc_end2
+  .cv_filechecksums                       # File index to string table offset subsection
+  .cv_stringtable                         # String table
+  .long 241
+  .long .Ltmp31-.Ltmp30                 # Subsection size
+.Ltmp30:
+  .short  .Ltmp33-.Ltmp32                 # Record length
+.Ltmp32:
+  .short  4428                            # Record kind: S_BUILDINFO
+  .long 4103                            # LF_BUILDINFO index
+  .p2align  2
+.Ltmp33:
+.Ltmp31:
+  .p2align  2
+  .section  .debug$T,"dr"
+  .p2align  2
+  .long 4                               # Debug section magic
+  # ArgList (0x1000)
+  .short  0x6                             # Record length
+  .short  0x1201                          # Record kind: LF_ARGLIST
+  .long 0x0                             # NumArgs
+  # Procedure (0x1001)
+  .short  0xe                             # Record length
+  .short  0x1008                          # Record kind: LF_PROCEDURE
+  .long 0x3                             # ReturnType: void
+  .byte 0x0                             # CallingConvention: NearC
+  .byte 0x0                             # FunctionOptions
+  .short  0x0                             # NumParameters
+  .long 0x1000                          # ArgListType: ()
+  # FuncId (0x1002)
+  .short  0xe                             # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1001                          # FunctionType: void ()
+  .asciz  "f1"                            # Name
+  .byte 241
+  # FuncId (0x1003)
+  .short  0xe                             # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1001                          # FunctionType: void ()
+  .asciz  "f2"                            # Name
+  .byte 241
+  # FuncId (0x1004)
+  .short  0x12                            # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1001                          # FunctionType: void ()
+  .asciz  "main"                          # Name
+  .byte 243
+  .byte 242
+  .byte 241
+  # StringId (0x1005)
+  .short  0x16                            # Record length
+  .short  0x1605                          # Record kind: LF_STRING_ID
+  .long 0x0                             # Id
+  .asciz  "C:\\src\\tests"                # StringData
+  .byte 243
+  .byte 242
+  .byte 241
+  # StringId (0x1006)
+  .short  0xe                             # Record length
+  .short  0x1605                          # Record kind: LF_STRING_ID
+  .long 0x0                             # Id
+  .asciz  "<stdin>"                       # StringData
+  # BuildInfo (0x1007)
+  .short  0x1a                            # Record length
+  .short  0x1603                          # Record kind: LF_BUILDINFO
+  .short  0x5                             # NumArgs
+  .long 0x1005                          # Argument: C:\src\tests
+  .long 0x0                             # Argument
+  .long 0x1006                          # Argument: <stdin>
+  .long 0x0                             # Argument
+  .long 0x0                             # Argument
+  .byte 242
+  .byte 241

llvm/lib/DebugInfo/PDB/Native/SymbolCache.cpp

for (const LineColumnEntry &Group : Lines) {
 
       std::vector<LineTableEntry> Entries;
 
       // If there are column numbers, then they should be in a parallel stream
       // to the line numbers.
       auto ColIt = Group.Columns.begin();
       auto ColsEnd = Group.Columns.end();
 
+      // Add a line to mark the beginning of this section.
+      uint64_t StartAddr =
+          Session.getVAFromSectOffset(RelocSegment, RelocOffset);
+      LineInfo FirstLine(Group.LineNumbers.front().Flags);
+      uint32_t ColNum =
+          (Lines.hasColumnInfo()) ? Group.Columns.front().StartColumn : 0;
+      Entries.push_back({StartAddr, FirstLine, ColNum, Group.NameIndex, false});
+
       for (const LineNumberEntry &LN : Group.LineNumbers) {
         uint64_t VA =
             Session.getVAFromSectOffset(RelocSegment, RelocOffset + LN.Offset);
         LineInfo Line(LN.Flags);
-        uint32_t ColNum = 0;
+        ColNum = 0;
 
         if (Lines.hasColumnInfo() && ColIt != ColsEnd) {
           ColNum = ColIt->StartColumn;
           ++ColIt;
         }
         Entries.push_back({VA, Line, ColNum, Group.NameIndex, false});
       }
 
       // Add a terminal entry line to mark the end of this subsection.
-      uint64_t VA = Session.getVAFromSectOffset(
-          RelocSegment, RelocOffset + Lines.header()->CodeSize);
+      uint64_t EndAddr = StartAddr + Lines.header()->CodeSize;
       LineInfo LastLine(Group.LineNumbers.back().Flags);
-      uint32_t ColNum =
-          (Lines.hasColumnInfo()) ? Group.Columns.back().StartColumn : 0;
-      Entries.push_back({VA, LastLine, ColNum, Group.NameIndex, true});
+      ColNum = (Lines.hasColumnInfo()) ? Group.Columns.back().StartColumn : 0;
+      Entries.push_back({EndAddr, LastLine, ColNum, Group.NameIndex, true});
 
       EntryList.push_back(Entries);
     }
   }
 
   // Sort EntryList, and add flattened contents to the line table.
   std::sort(EntryList.begin(), EntryList.end(),
             [](const std::vector<LineTableEntry> &LHS,