When computing the demanded bits of Load SDNodes, make sure that we are looking at the loaded-value operand and not the ptr result (in case of pre-inc loads).
rdar://13348420
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177596 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 35707e8..6424431 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1917,7 +1917,8 @@
}
case ISD::LOAD: {
LoadSDNode *LD = cast<LoadSDNode>(Op);
- if (ISD::isZEXTLoad(Op.getNode())) {
+ // If this is a ZEXTLoad and we are looking at the loaded value.
+ if (ISD::isZEXTLoad(Op.getNode()) && Op.getResNo() == 0) {
EVT VT = LD->getMemoryVT();
unsigned MemBits = VT.getScalarType().getSizeInBits();
KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - MemBits);
@@ -2287,17 +2288,20 @@
break;
}
- // Handle LOADX separately here. EXTLOAD case will fallthrough.
- if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Op)) {
- unsigned ExtType = LD->getExtensionType();
- switch (ExtType) {
- default: break;
- case ISD::SEXTLOAD: // '17' bits known
- Tmp = LD->getMemoryVT().getScalarType().getSizeInBits();
- return VTBits-Tmp+1;
- case ISD::ZEXTLOAD: // '16' bits known
- Tmp = LD->getMemoryVT().getScalarType().getSizeInBits();
- return VTBits-Tmp;
+ // If we are looking at the loaded value of the SDNode.
+ if (Op.getResNo() == 0) {
+ // Handle LOADX separately here. EXTLOAD case will fallthrough.
+ if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Op)) {
+ unsigned ExtType = LD->getExtensionType();
+ switch (ExtType) {
+ default: break;
+ case ISD::SEXTLOAD: // '17' bits known
+ Tmp = LD->getMemoryVT().getScalarType().getSizeInBits();
+ return VTBits-Tmp+1;
+ case ISD::ZEXTLOAD: // '16' bits known
+ Tmp = LD->getMemoryVT().getScalarType().getSizeInBits();
+ return VTBits-Tmp;
+ }
}
}