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

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.

Differential Revision: https://reviews.llvm.org/D93306

diff --git a/lld/test/COFF/symbolizer-line-numbers.s b/lld/test/COFF/symbolizer-line-numbers.s
new file mode 100644 (file)
index 0000000..679e94e
--- /dev/null
+++ b/lld/test/COFF/symbolizer-line-numbers.s
@@ -0,0 +1,322 @@
+# 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

diff --git a/llvm/lib/DebugInfo/PDB/Native/SymbolCache.cpp b/llvm/lib/DebugInfo/PDB/Native/SymbolCache.cpp
index 113fce6..1296be3 100644 (file)
--- a/llvm/lib/DebugInfo/PDB/Native/SymbolCache.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/SymbolCache.cpp
@@ -481,11 +481,19 @@ SymbolCache::findLineTable(uint16_t Modi) const {
       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;
@@ -495,12 +503,10 @@ SymbolCache::findLineTable(uint16_t Modi) const {
       }
 
       // 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);
     }