[llvm] r180129 - DAGCombine should not aggressively fold SEXT(VSETCC(...)) into a wider VSETCC without first checking the target's vector boolean contents.

[Owen Anderson]

Author: resistor
Date: Tue Apr 23 13:09:28 2013
New Revision: 180129

URL: http://llvm.org/viewvc/llvm-project?rev=180129&view=rev
Log:
DAGCombine should not aggressively fold SEXT(VSETCC(...)) into a wider VSETCC without first checking the target's vector boolean contents.
This exposed an issue with PowerPC AltiVec where it appears it was setting the wrong vector boolean contents.  The included change
fixes the PowerPC tests, and was OK'd by Hal.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=180129&r1=180128&r2=180129&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Tue Apr 23 13:09:28 2013
@@ -4451,7 +4451,9 @@ SDValue DAGCombiner::visitSIGN_EXTEND(SD
   if (N0.getOpcode() == ISD::SETCC) {
     // sext(setcc) -> sext_in_reg(vsetcc) for vectors.
     // Only do this before legalize for now.
-    if (VT.isVector() && !LegalOperations) {
+    if (VT.isVector() && !LegalOperations &&
+        TLI.getBooleanContents(true) == 
+          TargetLowering::ZeroOrNegativeOneBooleanContent) {
       EVT N0VT = N0.getOperand(0).getValueType();
       // On some architectures (such as SSE/NEON/etc) the SETCC result type is
       // of the same size as the compared operands. Only optimize sext(setcc())

Modified: llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp?rev=180129&r1=180128&r2=180129&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp Tue Apr 23 13:09:28 2013
@@ -514,7 +514,7 @@ PPCTargetLowering::PPCTargetLowering(PPC
   setOperationAction(ISD::ATOMIC_STORE, MVT::i64, Expand);
 
   setBooleanContents(ZeroOrOneBooleanContent);
-  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
+  setBooleanVectorContents(ZeroOrNegativeOneBooleanContent); // FIXME: Is this correct?
 
   if (isPPC64) {
     setStackPointerRegisterToSaveRestore(PPC::X1);