[DWARFv5] Number the line-table's directory array correctly.

The compilation directory has always been #0, but as of DWARF v5 it is
explicitly listed in the line-table section instead of implicitly
being a reference to the compile_unit DIE's DW_AT_comp_dir attribute.
This means the dumper should number the dumped array starting with 0
or 1 depending on the DWARF version of the line table.

References in the generated DWARF are correct, it's just the dumper
that was wrong.  Also some assembler-coded tests were similarly
confused about directory numbers.

llvm-svn: 322884

1 files changed, 5 insertions, 2 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
index 861122cfbaf..7bc6f10e516 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -73,10 +73,13 @@ void DWARFDebugLine::Prologue::dump(raw_ostream &OS) const {
     OS << format("standard_opcode_lengths[%s] = %u\n",
                  LNStandardString(I + 1).data(), StandardOpcodeLengths[I]);
 
-  if (!IncludeDirectories.empty())
+  if (!IncludeDirectories.empty()) {
+    // DWARF v5 starts directory indexes at 0.
+    uint32_t DirBase = getVersion() >= 5 ? 0 : 1;
     for (uint32_t I = 0; I != IncludeDirectories.size(); ++I)
-      OS << format("include_directories[%3u] = '", I + 1)
+      OS << format("include_directories[%3u] = '", I + DirBase)
          << IncludeDirectories[I] << "'\n";
+  }
 
   if (!FileNames.empty()) {
     if (HasMD5)