Fix CellSPU vector shuffles, again.
Some cases of lowering to rotate were miscompiled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113355 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CellSPU/SPUISelLowering.cpp b/lib/Target/CellSPU/SPUISelLowering.cpp
index 46f3189..7bac3f5 100644
--- a/lib/Target/CellSPU/SPUISelLowering.cpp
+++ b/lib/Target/CellSPU/SPUISelLowering.cpp
@@ -1735,9 +1735,9 @@
unsigned CurrElt = 0;
unsigned MaxElts = VecVT.getVectorNumElements();
unsigned PrevElt = 0;
- unsigned V0Elt = 0;
bool monotonic = true;
bool rotate = true;
+ int rotamt;
EVT maskVT; // which of the c?d instructions to use
if (EltVT == MVT::i8) {
@@ -1781,14 +1781,13 @@
if (PrevElt > 0 && SrcElt < MaxElts) {
if ((PrevElt == SrcElt - 1)
|| (PrevElt == MaxElts - 1 && SrcElt == 0)) {
+ rotamt = SrcElt-i;
PrevElt = SrcElt;
- if (SrcElt == 0)
- V0Elt = i;
} else {
rotate = false;
}
- } else if (i == 0) {
- // First time through, need to keep track of previous element
+ } else if (i == 0 || (PrevElt==0 && SrcElt==1)) {
+ // First time or after a "wrap around"
PrevElt = SrcElt;
} else {
// This isn't a rotation, takes elements from vector 2
@@ -1813,8 +1812,9 @@
return DAG.getNode(SPUISD::SHUFB, dl, V1.getValueType(), V2, V1,
ShufMaskOp);
} else if (rotate) {
- int rotamt = (MaxElts - V0Elt) * EltVT.getSizeInBits()/8;
-
+ if (rotamt < 0)
+ rotamt +=MaxElts;
+ rotamt *= EltVT.getSizeInBits()/8;
return DAG.getNode(SPUISD::ROTBYTES_LEFT, dl, V1.getValueType(),
V1, DAG.getConstant(rotamt, MVT::i16));
} else {