Optimize code a bit. No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154299 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Craig Topper 2012-04-08 23:15:04 +00:00
parent c47bc33218
commit 10612dc15f

View File

@ -2893,13 +2893,13 @@ void SelectionDAGBuilder::visitShuffleVector(const User &I) {
// Analyze the access pattern of the vector to see if we can extract
// two subvectors and do the shuffle. The analysis is done by calculating
// the range of elements the mask access on both vectors.
int MinRange[2] = { static_cast<int>(SrcNumElts+1),
static_cast<int>(SrcNumElts+1)};
int MinRange[2] = { static_cast<int>(SrcNumElts),
static_cast<int>(SrcNumElts)};
int MaxRange[2] = {-1, -1};
for (unsigned i = 0; i != MaskNumElts; ++i) {
int Idx = Mask[i];
int Input = 0;
unsigned Input = 0;
if (Idx < 0)
continue;
@ -2915,11 +2915,11 @@ void SelectionDAGBuilder::visitShuffleVector(const User &I) {
// Check if the access is smaller than the vector size and can we find
// a reasonable extract index.
int RangeUse[2] = { 2, 2 }; // 0 = Unused, 1 = Extract, 2 = Can not
// Extract.
int RangeUse[2] = { -1, -1 }; // 0 = Unused, 1 = Extract, -1 = Can not
// Extract.
int StartIdx[2]; // StartIdx to extract from
for (int Input=0; Input < 2; ++Input) {
if (MinRange[Input] == (int)(SrcNumElts+1) && MaxRange[Input] == -1) {
for (unsigned Input = 0; Input < 2; ++Input) {
if (MinRange[Input] >= (int)SrcNumElts && MaxRange[Input] < 0) {
RangeUse[Input] = 0; // Unused
StartIdx[Input] = 0;
continue;
@ -2937,9 +2937,9 @@ void SelectionDAGBuilder::visitShuffleVector(const User &I) {
setValue(&I, DAG.getUNDEF(VT)); // Vectors are not used.
return;
}
if (RangeUse[0] < 2 && RangeUse[1] < 2) {
if (RangeUse[0] >= 0 && RangeUse[1] >= 0) {
// Extract appropriate subvector and generate a vector shuffle
for (int Input=0; Input < 2; ++Input) {
for (unsigned Input = 0; Input < 2; ++Input) {
SDValue &Src = Input == 0 ? Src1 : Src2;
if (RangeUse[Input] == 0)
Src = DAG.getUNDEF(VT);