Fix a bug with insertelement on SPU.
The previous algorithm in LowerVECTOR_SHUFFLE
didn't check all requirements for "monotonic" shuffles.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111361 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CellSPU/SPUISelLowering.cpp b/lib/Target/CellSPU/SPUISelLowering.cpp
index d5f3fec..9741672 100644
--- a/lib/Target/CellSPU/SPUISelLowering.cpp
+++ b/lib/Target/CellSPU/SPUISelLowering.cpp
@@ -1755,11 +1755,12 @@
// If we have a single element being moved from V1 to V2, this can be handled
// using the C*[DX] compute mask instructions, but the vector elements have
- // to be monotonically increasing with one exception element.
+ // to be monotonically increasing with one exception element, and the source
+ // slot of the element to move must be the same as the destination.
EVT VecVT = V1.getValueType();
EVT EltVT = VecVT.getVectorElementType();
unsigned EltsFromV2 = 0;
- unsigned V2Elt = 0;
+ unsigned V2EltOffset = 0;
unsigned V2EltIdx0 = 0;
unsigned CurrElt = 0;
unsigned MaxElts = VecVT.getVectorNumElements();
@@ -1792,9 +1793,13 @@
if (monotonic) {
if (SrcElt >= V2EltIdx0) {
- if (1 >= (++EltsFromV2)) {
- V2Elt = (V2EltIdx0 - SrcElt) << 2;
- }
+ // TODO: optimize for the monotonic case when several consecutive
+ // elements are taken form V2. Do we ever get such a case?
+ if (EltsFromV2 == 0 && CurrElt == (SrcElt - V2EltIdx0))
+ V2EltOffset = (SrcElt - V2EltIdx0) * (EltVT.getSizeInBits()/8);
+ else
+ monotonic = false;
+ ++EltsFromV2;
} else if (CurrElt != SrcElt) {
monotonic = false;
}
@@ -1830,7 +1835,7 @@
// R1 ($sp) is used here only as it is guaranteed to have last bits zero
SDValue Pointer = DAG.getNode(SPUISD::IndirectAddr, dl, PtrVT,
DAG.getRegister(SPU::R1, PtrVT),
- DAG.getConstant(V2Elt, MVT::i32));
+ DAG.getConstant(V2EltOffset, MVT::i32));
SDValue ShufMaskOp = DAG.getNode(SPUISD::SHUFFLE_MASK, dl,
maskVT, Pointer);