[llvm-commits] Handling of DebugLocs during CSE of SelectionDAG nodes.

[Devang Patel]

On Oct 31, 2011, at 10:30 AM, Kyriakos Georgiou wrote:

> Regarding thread :
> 
> http://lists.cs.uiuc.edu/pipermail/llvmdev/2011-September/043205.html
> 
> the approach of throwing away the line number information on the merged node is
> implemented in the attached patch.

+    if (SDNode *ON = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+      DebugLoc dlN = N->getDebugLoc();
+      DebugLoc dlON = ON->getDebugLoc();
+      // Throw away the line number information on the merged node since it is
+      // not possible to preserve the information that operation is associated
+      // with multiple lines. This will make the debugger work better at -O0.
+      if (!(dlON.isUnknown()) && (OptLevel != CodeGenOpt::None) && (dlN != dlON)) {
+        ON->setDebugLoc(DebugLoc());
+      }

This logic could be separated out in a utility function. 
Do you have any test cases ?
-
Devang