Change SCEVExpander's expandCodeFor to provide more flexibility
with the persistent insertion point, and change IndVars to make
use of it. This fixes a bug where IndVars was holding on to a
stale insertion point and forcing the SCEVExpander to continue to
use it.
This fixes PR4038.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69892 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
index 80b47d8..9676ea2 100644
--- a/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -332,12 +332,10 @@
return LHS;
}
-Value *SCEVExpander::expandCodeFor(SCEVHandle SH, const Type *Ty,
- BasicBlock::iterator IP) {
+Value *SCEVExpander::expandCodeFor(SCEVHandle SH, const Type *Ty) {
// Expand the code for this SCEV.
assert(SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(SH->getType()) &&
"non-trivial casts should be done with the SCEVs directly!");
- InsertPt = IP;
Value *V = expand(SH);
return InsertNoopCastOfTo(V, Ty);
}
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp
index 63ef021..cc3919d 100644
--- a/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -543,8 +543,7 @@
ScalarEvolution *SE,
const Type *LargestType, Loop *L,
const Type *myType,
- SCEVExpander &Rewriter,
- BasicBlock::iterator InsertPt) {
+ SCEVExpander &Rewriter) {
SCEVHandle ExtendedStart =
SE->getSignExtendExpr(AR->getStart(), LargestType);
SCEVHandle ExtendedStep =
@@ -553,15 +552,14 @@
SE->getAddRecExpr(ExtendedStart, ExtendedStep, L);
if (LargestType != myType)
ExtendedAddRec = SE->getTruncateExpr(ExtendedAddRec, myType);
- return Rewriter.expandCodeFor(ExtendedAddRec, myType, InsertPt);
+ return Rewriter.expandCodeFor(ExtendedAddRec, myType);
}
static Value *getZeroExtendedTruncVar(const SCEVAddRecExpr *AR,
ScalarEvolution *SE,
const Type *LargestType, Loop *L,
const Type *myType,
- SCEVExpander &Rewriter,
- BasicBlock::iterator InsertPt) {
+ SCEVExpander &Rewriter) {
SCEVHandle ExtendedStart =
SE->getZeroExtendExpr(AR->getStart(), LargestType);
SCEVHandle ExtendedStep =
@@ -570,7 +568,7 @@
SE->getAddRecExpr(ExtendedStart, ExtendedStep, L);
if (LargestType != myType)
ExtendedAddRec = SE->getTruncateExpr(ExtendedAddRec, myType);
- return Rewriter.expandCodeFor(ExtendedAddRec, myType, InsertPt);
+ return Rewriter.expandCodeFor(ExtendedAddRec, myType);
}
/// allUsesAreSameTyped - See whether all Uses of I are instructions
@@ -699,6 +697,7 @@
// recurrences in terms of the induction variable. Start with the auxillary
// induction variables, and recursively rewrite any of their uses.
BasicBlock::iterator InsertPt = Header->getFirstNonPHI();
+ Rewriter.setInsertionPoint(InsertPt);
// If there were induction variables of other sizes, cast the primary
// induction variable to the right size for them, avoiding the need for the
@@ -718,7 +717,7 @@
while (!IndVars.empty()) {
PHINode *PN = IndVars.back().first;
const SCEVAddRecExpr *AR = cast<SCEVAddRecExpr>(IndVars.back().second);
- Value *NewVal = Rewriter.expandCodeFor(AR, PN->getType(), InsertPt);
+ Value *NewVal = Rewriter.expandCodeFor(AR, PN->getType());
DOUT << "INDVARS: Rewrote IV '" << *AR << "' " << *PN
<< " into = " << *NewVal << "\n";
NewVal->takeName(PN);
@@ -732,7 +731,7 @@
Instruction *UInst = dyn_cast<Instruction>(*UI);
if (UInst && isa<SExtInst>(UInst) && NoSignedWrap) {
Value *TruncIndVar = getSignExtendedTruncVar(AR, SE, LargestType, L,
- UInst->getType(), Rewriter, InsertPt);
+ UInst->getType(), Rewriter);
UInst->replaceAllUsesWith(TruncIndVar);
DeadInsts.insert(UInst);
}
@@ -753,8 +752,7 @@
SExtInst* oldSext = dyn_cast<SExtInst>(UInst->use_begin());
uint64_t truncSize = oldSext->getType()->getPrimitiveSizeInBits();
Value *TruncIndVar = getSignExtendedTruncVar(AR, SE, LargestType,
- L, oldSext->getType(), Rewriter,
- InsertPt);
+ L, oldSext->getType(), Rewriter);
APInt APnewAddRHS = APInt(AddRHS->getValue()).sext(newBitSize);
if (newBitSize > truncSize)
APnewAddRHS = APnewAddRHS.trunc(truncSize);
@@ -784,8 +782,7 @@
SExtInst* oldSext = dyn_cast<SExtInst>(UInst->use_begin());
uint64_t truncSize = oldSext->getType()->getPrimitiveSizeInBits();
Value *TruncIndVar = getSignExtendedTruncVar(AR, SE, LargestType,
- L, oldSext->getType(), Rewriter,
- InsertPt);
+ L, oldSext->getType(), Rewriter);
APInt APnewOrRHS = APInt(RHS->getValue()).sext(newBitSize);
if (newBitSize > truncSize)
APnewOrRHS = APnewOrRHS.trunc(truncSize);
@@ -805,7 +802,7 @@
// A zext of a signed variable known not to overflow is still safe.
if (UInst && isa<ZExtInst>(UInst) && (NoUnsignedWrap || NoSignedWrap)) {
Value *TruncIndVar = getZeroExtendedTruncVar(AR, SE, LargestType, L,
- UInst->getType(), Rewriter, InsertPt);
+ UInst->getType(), Rewriter);
UInst->replaceAllUsesWith(TruncIndVar);
DeadInsts.insert(UInst);
}
@@ -822,7 +819,7 @@
ZExtInst* oldZext = dyn_cast<ZExtInst>(UInst->use_begin());
uint64_t truncSize = oldZext->getType()->getPrimitiveSizeInBits();
Value *TruncIndVar = getSignExtendedTruncVar(AR, SE, LargestType,
- L, oldZext->getType(), Rewriter, InsertPt);
+ L, oldZext->getType(), Rewriter);
APInt APnewAndRHS = APInt(AndRHS->getValue()).zext(newBitSize);
if (newBitSize > truncSize)
APnewAndRHS = APnewAndRHS.trunc(truncSize);
@@ -858,7 +855,7 @@
ZExtInst* oldZext = dyn_cast<ZExtInst>(UInst2->use_begin());
uint64_t truncSize = oldZext->getType()->getPrimitiveSizeInBits();
Value *TruncIndVar = getSignExtendedTruncVar(AR, SE, LargestType,
- L, oldZext->getType(), Rewriter, InsertPt);
+ L, oldZext->getType(), Rewriter);
ConstantInt* AndRHS = dyn_cast<ConstantInt>(UInst2->getOperand(1));
APInt APnewAddRHS = APInt(AddRHS->getValue()).zext(newBitSize);
if (newBitSize > truncSize)