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[LoopVectorizer] LoopVectorBody doesn't need to be a vector. NFC. 

LoopVectorBody was changed from a single pointer to a SmallVector when
store predication was introduced in r200270. Since r247139, store predication
no longer splits the vector loop body in-place, so we can go back to having
a single LoopVectorBody block.

This reverts the no-longer-needed changes from r200270.

llvm-svn: 269321
This commit is contained in:
Michael Kuperstein 2016-05-12 18:44:51 +00:00
parent fc8892771e
commit 82e7df5a58
1 changed files with 22 additions and 40 deletions
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62
llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
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@ -559,7 +559,7 @@ protected:
/// The ExitBlock of the scalar loop.
BasicBlock *LoopExitBlock;
/// The vector loop body.
SmallVector<BasicBlock *, 4> LoopVectorBody;
BasicBlock *LoopVectorBody;
/// The scalar loop body.
BasicBlock *LoopScalarBody;
/// A list of all bypass blocks. The first block is the entry of the loop.
@ -2066,9 +2066,7 @@ struct LoopVectorize : public FunctionPass {
Value *InnerLoopVectorizer::getBroadcastInstrs(Value *V) {
// We need to place the broadcast of invariant variables outside the loop.
Instruction *Instr = dyn_cast<Instruction>(V);
bool NewInstr = (Instr &&
std::find(LoopVectorBody.begin(), LoopVectorBody.end(),
Instr->getParent()) != LoopVectorBody.end());
bool NewInstr = (Instr && Instr->getParent() == LoopVectorBody);
bool Invariant = OrigLoop->isLoopInvariant(V) && !NewInstr;
// Place the code for broadcasting invariant variables in the new preheader.
@ -3195,7 +3193,7 @@ void InnerLoopVectorizer::createEmptyLoop() {
LoopScalarPreHeader = ScalarPH;
LoopMiddleBlock = MiddleBlock;
LoopExitBlock = ExitBlock;
LoopVectorBody.push_back(VecBody);
LoopVectorBody = VecBody;
LoopScalarBody = OldBasicBlock;
// Keep all loop hints from the original loop on the vector loop (we'll
@ -3233,40 +3231,25 @@ struct CSEDenseMapInfo {
};
}
/// \brief Check whether this block is a predicated block.
/// Due to if predication of stores we might create a sequence of "if(pred) a[i]
/// = ...; " blocks. We start with one vectorized basic block. For every
/// conditional block we split this vectorized block. Therefore, every second
/// block will be a predicated one.
static bool isPredicatedBlock(unsigned BlockNum) { return BlockNum % 2; }
///\brief Perform cse of induction variable instructions.
static void cse(SmallVector<BasicBlock *, 4> &BBs) {
static void cse(BasicBlock *BB) {
// Perform simple cse.
SmallDenseMap<Instruction *, Instruction *, 4, CSEDenseMapInfo> CSEMap;
for (unsigned i = 0, e = BBs.size(); i != e; ++i) {
BasicBlock *BB = BBs[i];
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;) {
Instruction *In = &*I++;
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;) {
Instruction *In = &*I++;
if (!CSEDenseMapInfo::canHandle(In))
continue;
if (!CSEDenseMapInfo::canHandle(In))
continue;
// Check if we can replace this instruction with any of the
// visited instructions.
if (Instruction *V = CSEMap.lookup(In)) {
In->replaceAllUsesWith(V);
In->eraseFromParent();
continue;
}
// Ignore instructions in conditional blocks. We create "if (pred) a[i] =
// ...;" blocks for predicated stores. Every second block is a predicated
// block.
if (isPredicatedBlock(i))
continue;
CSEMap[In] = In;
// Check if we can replace this instruction with any of the
// visited instructions.
if (Instruction *V = CSEMap.lookup(In)) {
In->replaceAllUsesWith(V);
In->eraseFromParent();
continue;
}
CSEMap[In] = In;
}
}
@ -3613,7 +3596,7 @@ void InnerLoopVectorizer::vectorizeLoop() {
cast<PHINode>(VecRdxPhi[part])
->addIncoming(StartVal, LoopVectorPreHeader);
cast<PHINode>(VecRdxPhi[part])
->addIncoming(Val[part], LoopVectorBody.back());
->addIncoming(Val[part], LoopVectorBody);
}
// Before each round, move the insertion point right between
@ -3630,7 +3613,7 @@ void InnerLoopVectorizer::vectorizeLoop() {
// entire expression in the smaller type.
if (VF > 1 && Phi->getType() != RdxDesc.getRecurrenceType()) {
Type *RdxVecTy = VectorType::get(RdxDesc.getRecurrenceType(), VF);
Builder.SetInsertPoint(LoopVectorBody.back()->getTerminator());
Builder.SetInsertPoint(LoopVectorBody->getTerminator());
for (unsigned part = 0; part < UF; ++part) {
Value *Trunc = Builder.CreateTrunc(RdxParts[part], RdxVecTy);
Value *Extnd = RdxDesc.isSigned() ? Builder.CreateSExt(Trunc, VecTy)
@ -3884,7 +3867,7 @@ void InnerLoopVectorizer::fixFirstOrderRecurrence(PHINode *Phi) {
// Fix the latch value of the new recurrence in the vector loop.
VecPhi->addIncoming(Incoming,
LI->getLoopFor(LoopVectorBody[0])->getLoopLatch());
LI->getLoopFor(LoopVectorBody)->getLoopLatch());
// Extract the last vector element in the middle block. This will be the
// initial value for the recurrence when jumping to the scalar loop.
@ -4005,7 +3988,7 @@ void InnerLoopVectorizer::widenPHIInstruction(
Type *VecTy =
(VF == 1) ? PN->getType() : VectorType::get(PN->getType(), VF);
Entry[part] = PHINode::Create(
VecTy, 2, "vec.phi", &*LoopVectorBody.back()->getFirstInsertionPt());
VecTy, 2, "vec.phi", &*LoopVectorBody->getFirstInsertionPt());
}
PV->push_back(P);
return;
@ -4369,10 +4352,9 @@ void InnerLoopVectorizer::updateAnalysis() {
// We don't predicate stores by this point, so the vector body should be a
// single loop.
assert(LoopVectorBody.size() == 1 && "Expected single block loop!");
DT->addNewBlock(LoopVectorBody[0], LoopVectorPreHeader);
DT->addNewBlock(LoopVectorBody, LoopVectorPreHeader);
DT->addNewBlock(LoopMiddleBlock, LoopVectorBody.back());
DT->addNewBlock(LoopMiddleBlock, LoopVectorBody);
DT->addNewBlock(LoopScalarPreHeader, LoopBypassBlocks[0]);
DT->changeImmediateDominator(LoopScalarBody, LoopScalarPreHeader);
DT->changeImmediateDominator(LoopExitBlock, LoopBypassBlocks[0]);