DebugInfo: Fix for missing comp_dir handling with r349207

When deciding lazily whether a CU would be split or non-split I
accidentally dropped some handling for the line tables comp_dir (by
doing it lazily it was too late to be handled properly by the MC line
table code).

Move that bit of the code back to the non-lazy place.

llvm-svn: 349819

2 files changed, 42 insertions, 9 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 2d8c9e49738..71fbfaa567c 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -573,15 +573,6 @@ void DwarfDebug::finishUnitAttributes(const DICompileUnit *DIUnit,
   DIE &Die = NewCU.getUnitDie();
   StringRef FN = DIUnit->getFilename();
 
-  // LTO with assembly output shares a single line table amongst multiple CUs.
-  // To avoid the compilation directory being ambiguous, let the line table
-  // explicitly describe the directory of all files, never relying on the
-  // compilation directory.
-  if (!Asm->OutStreamer->hasRawTextSupport() || SingleCU)
-    Asm->OutStreamer->emitDwarfFile0Directive(
-        CompilationDir, FN, NewCU.getMD5AsBytes(DIUnit->getFile()),
-        DIUnit->getSource(), NewCU.getUniqueID());
-
   StringRef Producer = DIUnit->getProducer();
   StringRef Flags = DIUnit->getFlags();
   if (!Flags.empty() && !useAppleExtensionAttributes()) {
@@ -649,6 +640,16 @@ DwarfDebug::getOrCreateDwarfCompileUnit(const DICompileUnit *DIUnit) {
   for (auto *IE : DIUnit->getImportedEntities())
     NewCU.addImportedEntity(IE);
 
+  // LTO with assembly output shares a single line table amongst multiple CUs.
+  // To avoid the compilation directory being ambiguous, let the line table
+  // explicitly describe the directory of all files, never relying on the
+  // compilation directory.
+  if (!Asm->OutStreamer->hasRawTextSupport() || SingleCU)
+    Asm->OutStreamer->emitDwarfFile0Directive(
+        CompilationDir, DIUnit->getFilename(),
+        NewCU.getMD5AsBytes(DIUnit->getFile()), DIUnit->getSource(),
+        NewCU.getUniqueID());
+
   if (useSplitDwarf()) {
     NewCU.setSkeleton(constructSkeletonCU(NewCU));
     NewCU.setSection(Asm->getObjFileLowering().getDwarfInfoDWOSection());
diff --git a/llvm/test/DebugInfo/X86/lazy-fission-comp-dir.ll b/llvm/test/DebugInfo/X86/lazy-fission-comp-dir.ll
new file mode 100644
index 00000000000..6055e7ecd3e
--- /dev/null
+++ b/llvm/test/DebugInfo/X86/lazy-fission-comp-dir.ll
@@ -0,0 +1,32 @@
+; RUN: llc -split-dwarf-file=foo.dwo -O0 %s -mtriple=x86_64-unknown-linux-gnu -filetype=obj -o %t
+; RUN: llvm-dwarfdump -debug-info -debug-line %t | FileCheck %s
+
+; CHECK: .debug_info contents:
+; CHECK: DW_AT_comp_dir ("/usr/local/google/home/blaikie/dev/scratch")
+
+; CHECK: .debug_line contents:
+; CHECK: file_names[ 1]:
+; CHECK-NEXT:      name: "main.c"
+; CHECK-NEXT: dir_index: 0
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @main() !dbg !6 {
+entry:
+  ret i32 0, !dbg !10
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+!llvm.ident = !{!5}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 8.0.0 (trunk 349782) (llvm/trunk 349794)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: GNU)
+!1 = !DIFile(filename: "main.c", directory: "/usr/local/google/home/blaikie/dev/scratch")
+!2 = !{}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = !{i32 1, !"wchar_size", i32 4}
+!5 = !{!"clang version 8.0.0 (trunk 349782) (llvm/trunk 349794)"}
+!6 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 1, type: !7, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!7 = !DISubroutineType(types: !8)
+!8 = !{!9}
+!9 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!10 = !DILocation(line: 2, column: 1, scope: !6)