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Merge pull request #973 from Vsevolod-Livinskij/smear_opt

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Smear opt
This commit is contained in:
jbrodman
2015-02-20 13:34:44 -08:00
parent 6c5ed87c59 f17deafc0a
commit 24fb2b483b
1 changed files with 34 additions and 4 deletions
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38
cbackend.cpp
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@@ -4672,10 +4672,10 @@ SmearCleanupPass::getShuffleSmearValue(llvm::Instruction* inst) const {
llvm::Constant* mask =
llvm::dyn_cast<llvm::Constant>(shuffleInst->getOperand(2));
// Check that the shuffle is a broadcast of the first element of the first vector,
// i.e. mask vector is all-zeros vector of expected size.
// Check that the shuffle is a broadcast of the element of the first vector,
// i.e. mask vector is vector with equal elements of expected size.
if (!(mask &&
mask->isNullValue() &&
(mask->isNullValue() || (shuffleInst->getMask()->getSplatValue() != 0))&&
llvm::dyn_cast<llvm::VectorType>(mask->getType())->getNumElements() == vectorWidth)) {
return NULL;
}
@@ -4688,7 +4688,37 @@ SmearCleanupPass::getShuffleSmearValue(llvm::Instruction* inst) const {
if (!(insertInst &&
llvm::isa<llvm::Constant>(insertInst->getOperand(2)) &&
llvm::dyn_cast<llvm::Constant>(insertInst->getOperand(2))->isNullValue())) {
return NULL;
// We can't extract element from vec1
llvm::VectorType *operandVec = llvm::dyn_cast<llvm::VectorType>(shuffleInst->getOperand(0)->getType());
if (operandVec && operandVec->getNumElements() == 1)
return NULL;
// Insert ExtractElementInstr to get value for smear
llvm::Function *extractFunc = module->getFunction("__extract_element");
if (extractFunc == NULL) {
// Declare the __extract_element function if needed; it takes a vector and
// a scalar parameter and returns a scalar of the vector parameter type.
llvm::Constant *ef =
module->getOrInsertFunction("__extract_element",
shuffleInst->getOperand(0)->getType()->getVectorElementType(),
shuffleInst->getOperand(0)->getType(),
llvm::IntegerType::get(module->getContext(), 32), NULL);
extractFunc = llvm::dyn_cast<llvm::Function>(ef);
assert(extractFunc != NULL);
extractFunc->setDoesNotThrow();
extractFunc->setOnlyReadsMemory();
}
if (extractFunc == NULL) {
return NULL;
}
llvm::Instruction *extractCall =
llvm::ExtractElementInst::Create(shuffleInst->getOperand(0), mask->getSplatValue(),
"__extract_element", inst);
return extractCall;
}
llvm::Value *result = insertInst->getOperand(1);