Avoid using lossy load / stores for memcpy / memset expansion. e.g.
f64 load / store on non-SSE2 x86 targets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169944 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 4cb63ce..36592e5 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3474,27 +3474,33 @@
unsigned VTSize = VT.getSizeInBits() / 8;
while (VTSize > Size) {
// For now, only use non-vector load / store's for the left-over pieces.
- EVT NewVT;
+ EVT NewVT = VT;
unsigned NewVTSize;
+
+ bool Found = false;
if (VT.isVector() || VT.isFloatingPoint()) {
NewVT = (VT.getSizeInBits() > 64) ? MVT::i64 : MVT::i32;
- while (!TLI.isOperationLegalOrCustom(ISD::STORE, NewVT)) {
- if (NewVT == MVT::i64 &&
- TLI.isOperationLegalOrCustom(ISD::STORE, MVT::f64)) {
- // i64 is usually not legal on 32-bit targets, but f64 may be.
- NewVT = MVT::f64;
- break;
- }
- NewVT = (MVT::SimpleValueType)(NewVT.getSimpleVT().SimpleTy - 1);
+ if (TLI.isOperationLegalOrCustom(ISD::STORE, NewVT) &&
+ TLI.isLegalMemOpType(NewVT.getSimpleVT()))
+ Found = true;
+ else if (NewVT == MVT::i64 &&
+ TLI.isOperationLegalOrCustom(ISD::STORE, MVT::f64) &&
+ TLI.isLegalMemOpType(MVT::f64)) {
+ // i64 is usually not legal on 32-bit targets, but f64 may be.
+ NewVT = MVT::f64;
+ Found = true;
}
- NewVTSize = NewVT.getSizeInBits() / 8;
- } else {
- // This can result in a type that is not legal on the target, e.g.
- // 1 or 2 bytes on PPC.
- NewVT = (MVT::SimpleValueType)(VT.getSimpleVT().SimpleTy - 1);
- NewVTSize = VTSize >> 1;
}
+ if (!Found) {
+ do {
+ NewVT = (MVT::SimpleValueType)(NewVT.getSimpleVT().SimpleTy - 1);
+ if (NewVT == MVT::i8)
+ break;
+ } while (!TLI.isLegalMemOpType(NewVT.getSimpleVT()));
+ }
+ NewVTSize = NewVT.getSizeInBits() / 8;
+
// If the new VT cannot cover all of the remaining bits, then consider
// issuing a (or a pair of) unaligned and overlapping load / store.
// FIXME: Only does this for 64-bit or more since we don't have proper