Revert "Reapply "[DWARFv5] Emit file 0 to the line table.""

This reverts commit r328676.

Commit r328676 broke the -no-integrated-as flag necessary to build Linux kernel with Clang:

$ cat t.c
void foo() {}
$ clang -no-integrated-as   -c  t.c -g
/tmp/t-dcdec5.s: Assembler messages:
/tmp/t-dcdec5.s:8: Error: file number less than one
clang-7.0: error: assembler command failed with exit code 1 (use -v to see invocation)

llvm-svn: 328699

3 files changed, 9 insertions, 12 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 0398d0f4c97..024472db87c 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -499,9 +499,8 @@ DwarfDebug::getOrCreateDwarfCompileUnit(const DICompileUnit *DIUnit) {
   // 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());
+    Asm->OutStreamer->getContext().setMCLineTableCompilationDir(
+        NewCU.getUniqueID(), CompilationDir);
 
   StringRef Producer = DIUnit->getProducer();
   StringRef Flags = DIUnit->getFlags();
@@ -2149,10 +2148,8 @@ void DwarfDebug::emitDebugStrDWO() {
 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
   if (!useSplitDwarf())
     return nullptr;
-  const DICompileUnit *DIUnit = CU.getCUNode();
-  SplitTypeUnitFileTable.maybeSetRootFile(
-      DIUnit->getDirectory(), DIUnit->getFilename(),
-      CU.getMD5AsBytes(DIUnit->getFile()), DIUnit->getSource());
+  if (SingleCU)
+    SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode()->getDirectory());
   return &SplitTypeUnitFileTable;
 }
 
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index a0cd34ea76f..811112a0430 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -282,7 +282,7 @@ void DwarfUnit::addSectionOffset(DIE &Die, dwarf::Attribute Attribute,
     addUInt(Die, Attribute, dwarf::DW_FORM_data4, Integer);
 }
 
-MD5::MD5Result *DwarfUnit::getMD5AsBytes(const DIFile *File) const {
+MD5::MD5Result *DwarfUnit::getMD5AsBytes(const DIFile *File) {
   assert(File);
   Optional<DIFile::ChecksumInfo<StringRef>> Checksum = File->getChecksum();
   if (!Checksum || Checksum->Kind != DIFile::CSK_MD5)
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
index c1d46173567..328e3549e05 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -306,10 +306,6 @@ public:
                                       const MCSymbol *Label,
                                       const MCSymbol *Sec);
 
-  /// If the \p File has an MD5 checksum, return it as an MD5Result
-  /// allocated in the MCContext.
-  MD5::MD5Result *getMD5AsBytes(const DIFile *File) const;
-
 protected:
   ~DwarfUnit();
 
@@ -320,6 +316,10 @@ protected:
   /// create a new ID and insert it in the line table.
   virtual unsigned getOrCreateSourceID(const DIFile *File) = 0;
 
+  /// If the \p File has an MD5 checksum, return it as an MD5Result
+  /// allocated in the MCContext.
+  MD5::MD5Result *getMD5AsBytes(const DIFile *File);
+
   /// Look in the DwarfDebug map for the MDNode that corresponds to the
   /// reference.
   template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {