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[LoopInterchange] Various cleanup. NFC. 

llvm-svn: 282071
This commit is contained in:
Chad Rosier 2016-09-21 13:28:41 +00:00
parent 357ef99917
commit f7c76f91e0
1 changed files with 19 additions and 23 deletions
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42
llvm/lib/Transforms/Scalar/LoopInterchange.cpp
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@ -312,8 +312,7 @@ static PHINode *getInductionVariable(Loop *L, ScalarEvolution *SE) {
if (!AddRec || !AddRec->isAffine())
continue;
const SCEV *Step = AddRec->getStepRecurrence(*SE);
const SCEVConstant *C = dyn_cast<SCEVConstant>(Step);
if (!C)
if (!isa<SCEVConstant>(Step))
continue;
// Found the induction variable.
// FIXME: Handle loops with more than one induction variable. Note that,
@ -471,7 +470,7 @@ struct LoopInterchange : public FunctionPass {
for (Loop *L : LoopList) {
const SCEV *ExitCountOuter = SE->getBackedgeTakenCount(L);
if (ExitCountOuter == SE->getCouldNotCompute()) {
DEBUG(dbgs() << "Couldn't compute Backedge count\n");
DEBUG(dbgs() << "Couldn't compute backedge count\n");
return false;
}
if (L->getNumBackEdges() != 1) {
@ -479,7 +478,7 @@ struct LoopInterchange : public FunctionPass {
return false;
}
if (!L->getExitingBlock()) {
DEBUG(dbgs() << "Loop Doesn't have unique exit block\n");
DEBUG(dbgs() << "Loop doesn't have unique exit block\n");
return false;
}
}
@ -516,7 +515,7 @@ struct LoopInterchange : public FunctionPass {
Loop *OuterMostLoop = *(LoopList.begin());
if (!populateDependencyMatrix(DependencyMatrix, LoopNestDepth,
OuterMostLoop, DI)) {
DEBUG(dbgs() << "Populating Dependency matrix failed\n");
DEBUG(dbgs() << "Populating dependency matrix failed\n");
return false;
}
#ifdef DUMP_DEP_MATRICIES
@ -587,7 +586,7 @@ struct LoopInterchange : public FunctionPass {
DEBUG(dbgs() << "Loops are legal to interchange\n");
LoopInterchangeProfitability LIP(OuterLoop, InnerLoop, SE);
if (!LIP.isProfitable(InnerLoopId, OuterLoopId, DependencyMatrix)) {
DEBUG(dbgs() << "Interchanging Loops not profitable\n");
DEBUG(dbgs() << "Interchanging loops not profitable\n");
return false;
}
@ -628,8 +627,7 @@ bool LoopInterchangeLegality::containsUnsafeInstructionsInLatch(
// Stores corresponding to reductions are safe while concluding if tightly
// nested.
if (StoreInst *L = dyn_cast<StoreInst>(I)) {
PHINode *PHI = dyn_cast<PHINode>(L->getOperand(0));
if (!PHI)
if (!isa<PHINode>(L->getOperand(0)))
return true;
} else if (I->mayHaveSideEffects() || I->mayReadFromMemory())
return true;
@ -642,30 +640,30 @@ bool LoopInterchangeLegality::tightlyNested(Loop *OuterLoop, Loop *InnerLoop) {
BasicBlock *InnerLoopPreHeader = InnerLoop->getLoopPreheader();
BasicBlock *OuterLoopLatch = OuterLoop->getLoopLatch();
DEBUG(dbgs() << "Checking if Loops are Tightly Nested\n");
DEBUG(dbgs() << "Checking if loops are tightly nested\n");
// A perfectly nested loop will not have any branch in between the outer and
// inner block i.e. outer header will branch to either inner preheader and
// outerloop latch.
BranchInst *outerLoopHeaderBI =
BranchInst *OuterLoopHeaderBI =
dyn_cast<BranchInst>(OuterLoopHeader->getTerminator());
if (!outerLoopHeaderBI)
if (!OuterLoopHeaderBI)
return false;
unsigned num = outerLoopHeaderBI->getNumSuccessors();
for (unsigned i = 0; i < num; i++) {
if (outerLoopHeaderBI->getSuccessor(i) != InnerLoopPreHeader &&
outerLoopHeaderBI->getSuccessor(i) != OuterLoopLatch)
for (unsigned i = 0, e = OuterLoopHeaderBI->getNumSuccessors(); i < e; ++i) {
if (OuterLoopHeaderBI->getSuccessor(i) != InnerLoopPreHeader &&
OuterLoopHeaderBI->getSuccessor(i) != OuterLoopLatch)
return false;
}
DEBUG(dbgs() << "Checking instructions in Loop header and Loop latch \n");
DEBUG(dbgs() << "Checking instructions in Loop header and Loop latch\n");
// We do not have any basic block in between now make sure the outer header
// and outer loop latch doesn't contain any unsafe instructions.
if (containsUnsafeInstructionsInHeader(OuterLoopHeader) ||
containsUnsafeInstructionsInLatch(OuterLoopLatch))
return false;
DEBUG(dbgs() << "Loops are perfectly nested \n");
DEBUG(dbgs() << "Loops are perfectly nested\n");
// We have a perfect loop nest.
return true;
}
@ -1023,8 +1021,6 @@ void LoopInterchangeTransform::restructureLoops(Loop *InnerLoop,
}
bool LoopInterchangeTransform::transform() {
DEBUG(dbgs() << "transform\n");
bool Transformed = false;
Instruction *InnerIndexVar;
@ -1047,16 +1043,16 @@ bool LoopInterchangeTransform::transform() {
// incremented/decremented.
// TODO: This splitting logic may not work always. Fix this.
splitInnerLoopLatch(InnerIndexVar);
DEBUG(dbgs() << "splitInnerLoopLatch Done\n");
DEBUG(dbgs() << "splitInnerLoopLatch done\n");
// Splits the inner loops phi nodes out into a separate basic block.
splitInnerLoopHeader();
DEBUG(dbgs() << "splitInnerLoopHeader Done\n");
DEBUG(dbgs() << "splitInnerLoopHeader done\n");
}
Transformed |= adjustLoopLinks();
if (!Transformed) {
DEBUG(dbgs() << "adjustLoopLinks Failed\n");
DEBUG(dbgs() << "adjustLoopLinks failed\n");
return false;
}
@ -1100,7 +1096,7 @@ void LoopInterchangeTransform::splitInnerLoopHeader() {
}
DEBUG(dbgs() << "Output of splitInnerLoopHeader InnerLoopHeaderSucc & "
"InnerLoopHeader \n");
"InnerLoopHeader\n");
}
/// \brief Move all instructions except the terminator from FromBB right before