[DWARF] Missing location debug information with -O2.

Check that Machine CSE correctly handles during the transformation, the
debug location information for local variables.

Differential Revision: https://reviews.llvm.org/D50887

llvm-svn: 341025

1 files changed, 1 insertions, 20 deletions

diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
index 1fd40f75735..d52e6198d4e 100644
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -513,25 +513,6 @@ bool MachineSinking::PostponeSplitCriticalEdge(MachineInstr &MI,
   return true;
 }
 
-/// collectDebgValues - Scan instructions following MI and collect any
-/// matching DBG_VALUEs.
-static void collectDebugValues(MachineInstr &MI,
-                               SmallVectorImpl<MachineInstr *> &DbgValues) {
-  DbgValues.clear();
-  if (!MI.getOperand(0).isReg())
-    return;
-
-  MachineBasicBlock::iterator DI = MI; ++DI;
-  for (MachineBasicBlock::iterator DE = MI.getParent()->end();
-       DI != DE; ++DI) {
-    if (!DI->isDebugValue())
-      return;
-    if (DI->getOperand(0).isReg() &&
-        DI->getOperand(0).getReg() == MI.getOperand(0).getReg())
-      DbgValues.push_back(&*DI);
-  }
-}
-
 /// isProfitableToSinkTo - Return true if it is profitable to sink MI.
 bool MachineSinking::isProfitableToSinkTo(unsigned Reg, MachineInstr &MI,
                                           MachineBasicBlock *MBB,
@@ -758,7 +739,7 @@ static void performSink(MachineInstr &MI, MachineBasicBlock &SuccToSinkTo,
                         MachineBasicBlock::iterator InsertPos) {
   // Collect matching debug values.
   SmallVector<MachineInstr *, 2> DbgValuesToSink;
-  collectDebugValues(MI, DbgValuesToSink);
+  MI.collectDebugValues(DbgValuesToSink);
 
   // If we cannot find a location to use (merge with), then we erase the debug
   // location to prevent debug-info driven tools from potentially reporting