Use debug-prefix-map for AT_NAME

AT_NAME was being emitted before the directory paths were remapped. This
ensures that all paths are remapped before anything is emitted.

An additional test case has been added.

Note that this only works if the replacement string is an absolute path.
If not, then AT_decl_file believes the new path is a relative path, and
joins that path with the compilation directory. I do not know of a good
way to resolve this.

Patch by: Siddhartha Bagaria (starsid)

Differential revision: https://reviews.llvm.org/D49169

llvm-svn: 336793

3 files changed, 20 insertions, 21 deletions

diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
index b601ab24434..606da252689 100644
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -540,19 +540,26 @@ void MCContext::addDebugPrefixMapEntry(const std::string &From,
   DebugPrefixMap.insert(std::make_pair(From, To));
 }
 
-void MCContext::RemapDebugPath(std::string *Path) {
-  for (const auto &Entry : DebugPrefixMap)
-    if (StringRef(*Path).startswith(Entry.first)) {
-      std::string RemappedPath =
-          (Twine(Entry.second) + Path->substr(Entry.first.size())).str();
-      Path->swap(RemappedPath);
-    }
-}
-
-void MCContext::RemapCompilationDir() {
+void MCContext::RemapDebugPaths() {
+  const auto &DebugPrefixMap = this->DebugPrefixMap;
+  const auto RemapDebugPath = [&DebugPrefixMap](std::string &Path) {
+    for (const auto &Entry : DebugPrefixMap)
+      if (StringRef(Path).startswith(Entry.first)) {
+        std::string RemappedPath =
+            (Twine(Entry.second) + Path.substr(Entry.first.size())).str();
+        Path.swap(RemappedPath);
+      }
+  };
+
+  // Remap compilation directory.
   std::string CompDir = CompilationDir.str();
-  RemapDebugPath(&CompDir);
+  RemapDebugPath(CompDir);
   CompilationDir = CompDir;
+
+  // Remap MCDwarfDirs in all compilation units.
+  for (auto &CUIDTablePair : MCDwarfLineTablesCUMap)
+    for (auto &Dir : CUIDTablePair.second.getMCDwarfDirs())
+      RemapDebugPath(Dir);
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/MC/MCDwarf.cpp b/llvm/lib/MC/MCDwarf.cpp
index 1d33d9947be..6131fcd658b 100644
--- a/llvm/lib/MC/MCDwarf.cpp
+++ b/llvm/lib/MC/MCDwarf.cpp
@@ -251,9 +251,7 @@ void MCDwarfLineTable::Emit(MCObjectStreamer *MCOS,
 
   // Handle the rest of the Compile Units.
   for (const auto &CUIDTablePair : LineTables) {
-    auto &LineTable = context.getMCDwarfLineTable(CUIDTablePair.first);
-    LineTable.RemapDwarfDirs(MCOS->getContext());
-    LineTable.EmitCU(MCOS, Params, LineStr);
+    CUIDTablePair.second.EmitCU(MCOS, Params, LineStr);
   }
 
   if (LineStr)
@@ -634,11 +632,6 @@ MCDwarfLineTableHeader::tryGetFile(StringRef &Directory,
   return FileNumber;
 }
 
-void MCDwarfLineTable::RemapDwarfDirs(MCContext &Context) {
-  for (auto &Dir : Header.MCDwarfDirs)
-    Context.RemapDebugPath(&Dir);
-}
-
 /// Utility function to emit the encoding to a streamer.
 void MCDwarfLineAddr::Emit(MCStreamer *MCOS, MCDwarfLineTableParams Params,
                            int64_t LineDelta, uint64_t AddrDelta) {
diff --git a/llvm/lib/MC/MCObjectStreamer.cpp b/llvm/lib/MC/MCObjectStreamer.cpp
index 9fab8d835f8..9d536883b98 100644
--- a/llvm/lib/MC/MCObjectStreamer.cpp
+++ b/llvm/lib/MC/MCObjectStreamer.cpp
@@ -661,8 +661,7 @@ void MCObjectStreamer::EmitFileDirective(StringRef Filename) {
 }
 
 void MCObjectStreamer::FinishImpl() {
-  // Remap the compilation directory before emitting.
-  getContext().RemapCompilationDir();
+  getContext().RemapDebugPaths();
 
   // If we are generating dwarf for assembly source files dump out the sections.
   if (getContext().getGenDwarfForAssembly())