Do not treat beginning of inlined scope as beginning of normal function scope if the location info is missing.

Insetad of doing ...
if (inlined_subroutine && known_location)
  DW_TAG_inline_subroutine
else
  DW_TAG_subprogram

do

if (inlined_subroutine) {
 if (known_location)
   DW_TAG_inline_subroutine
} else {
 DW_TAG_subprogram
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69300 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 2 deletions

diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 9a2491959d..12b0b12c40 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -362,7 +362,10 @@ bool FastISel::SelectCall(User *I) {
         const TargetInstrDesc &II = TII.get(TargetInstrInfo::DBG_LABEL);
         ID = DW->RecordInlinedFnEnd(Subprogram);
         if (ID)
-          // If ID is 0 then this was not an end of inlined region.
+          // Returned ID is 0 if this is unbalanced "end of inlined
+          // scope". This could happen if optimizer eats dbg intrinsics
+          // or "beginning of inlined scope" is not recoginized due to
+          // missing location info. In such cases, do ignore this region.end.
           BuildMI(MBB, DL, II).addImm(ID);
       } else {
         const TargetInstrDesc &II = TII.get(TargetInstrInfo::DBG_LABEL);
@@ -387,9 +390,14 @@ bool FastISel::SelectCall(User *I) {
       unsigned SrcFile = DW->getOrCreateSourceID(CompileUnit.getDirectory(Dir),
                                                  CompileUnit.getFilename(FN));
 
-      if (!Subprogram.describes(MF.getFunction()) && !PrevLoc.isUnknown()) {
+      if (!Subprogram.describes(MF.getFunction())) {
         // This is a beginning of an inlined function.
         
+        // If llvm.dbg.func.start is seen in a new block before any
+        // llvm.dbg.stoppoint intrinsic then the location info is unknown.
+        // FIXME : Why DebugLoc is reset at the beginning of each block ?
+        if (PrevLoc.isUnknown())
+          return true;
         // Record the source line.
         unsigned Line = Subprogram.getLineNumber();
         unsigned LabelID = DW->RecordSourceLine(Line, 0, SrcFile);