[llvm] r316968 - Undo accidental commit
Philip Reames via llvm-commits
llvm-commits at lists.llvm.org
Mon Oct 30 17:04:09 PDT 2017
Author: reames
Date: Mon Oct 30 17:04:09 2017
New Revision: 316968
URL: http://llvm.org/viewvc/llvm-project?rev=316968&view=rev
Log:
Undo accidental commit
These files shouldn't have been submitted in 316967
Modified:
llvm/trunk/lib/Analysis/ScalarEvolutionExpander.cpp
llvm/trunk/lib/Transforms/Utils/SimplifyIndVar.cpp
Modified: llvm/trunk/lib/Analysis/ScalarEvolutionExpander.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolutionExpander.cpp?rev=316968&r1=316967&r2=316968&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolutionExpander.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolutionExpander.cpp Mon Oct 30 17:04:09 2017
@@ -1690,13 +1690,8 @@ SCEVExpander::FindValueInExprValueMap(co
// the LCSSA form.
for (auto const &VOPair : *Set) {
Value *V = VOPair.first;
- dbgs() << "found " << *V << "\n";
ConstantInt *Offset = VOPair.second;
Instruction *EntInst = nullptr;
- if (V && isa<Constant>(V))
- return {V, Offset};
- if (V && isa<Argument>(V))
- return {V, Offset};
if (V && isa<Instruction>(V) && (EntInst = cast<Instruction>(V)) &&
S->getType() == V->getType() &&
EntInst->getFunction() == InsertPt->getFunction() &&
@@ -1707,9 +1702,6 @@ SCEVExpander::FindValueInExprValueMap(co
}
}
}
- if (auto *C = dyn_cast<SCEVConstant>(S))
- return {C->getValue(), nullptr};
- dbgs() << "Reject: " << *S << "\n";
return {nullptr, nullptr};
}
Modified: llvm/trunk/lib/Transforms/Utils/SimplifyIndVar.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyIndVar.cpp?rev=316968&r1=316967&r2=316968&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyIndVar.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SimplifyIndVar.cpp Mon Oct 30 17:04:09 2017
@@ -83,7 +83,6 @@ namespace {
bool eliminateOverflowIntrinsic(CallInst *CI);
bool eliminateIVUser(Instruction *UseInst, Instruction *IVOperand);
- bool makeIVComparisonInvariant(ICmpInst *ICmp, Value *IVOperand);
void eliminateIVComparison(ICmpInst *ICmp, Value *IVOperand);
void simplifyIVRemainder(BinaryOperator *Rem, Value *IVOperand,
bool IsSigned);
@@ -162,240 +161,6 @@ Value *SimplifyIndvar::foldIVUser(Instru
return IVSrc;
}
-#if 0
-bool SimplifyIndvar::isSimpleLoopInvariantPredicate(
- ICmpInst::Predicate Pred, const SCEV *LHS,
- const SCEV *RHS, const Loop *L,
- ICmpInst::Predicate &InvariantPred,
- Value *&NewLHS,
- Value *&NewRHS) {
- ICmpInst::Predicate InvariantPredicate;
- const SCEV *InvariantLHS, *InvariantRHS;
-
- if (!isa<PHINode>(IVOperand))
- return false;
- if (!SE->isLoopInvariantPredicate(Pred, S, X, L, InvariantPredicate,
- InvariantLHS, InvariantRHS))
- return false;
-
- // Rewrite the comparison to a loop invariant comparison if it can be done
- // cheaply, where cheaply means "we don't need to emit any new
- // instructions".
-
- Value *NewLHS = nullptr, *NewRHS = nullptr;
-
- if (LHS == InvariantLHS)
- NewLHS = LHS;
- else if (RHS == InvariantLHS)
- NewLHS = RHS;
-
- if (LHS == InvariantRHS)
- NewRHS = LHS;
- else if (RHS == InvariantRHS)
- NewRHS = RHS;
-
-
- if (S == InvariantLHS || X == InvariantLHS)
- NewLHS =
- ICmp->getOperand(S == InvariantLHS ? IVOperIdx : (1 - IVOperIdx));
-
- if (S == InvariantRHS || X == InvariantRHS)
- NewRHS =
- ICmp->getOperand(S == InvariantRHS ? IVOperIdx : (1 - IVOperIdx));
-
- auto *PN = cast<PHINode>(IVOperand);
- for (unsigned i = 0, e = PN->getNumIncomingValues();
- i != e && (!NewLHS || !NewRHS);
- ++i) {
-
- // If this is a value incoming from the backedge, then it cannot be a loop
- // invariant value (since we know that IVOperand is an induction variable).
- if (L->contains(PN->getIncomingBlock(i)))
- continue;
-
- // NB! This following assert does not fundamentally have to be true, but
- // it is true today given how SCEV analyzes induction variables.
- // Specifically, today SCEV will *not* recognize %iv as an induction
- // variable in the following case:
- //
- // define void @f(i32 %k) {
- // entry:
- // br i1 undef, label %r, label %l
- //
- // l:
- // %k.inc.l = add i32 %k, 1
- // br label %loop
- //
- // r:
- // %k.inc.r = add i32 %k, 1
- // br label %loop
- //
- // loop:
- // %iv = phi i32 [ %k.inc.l, %l ], [ %k.inc.r, %r ], [ %iv.inc, %loop ]
- // %iv.inc = add i32 %iv, 1
- // br label %loop
- // }
- //
- // but if it starts to, at some point, then the assertion below will have
- // to be changed to a runtime check.
-
- Value *Incoming = PN->getIncomingValue(i);
-
-#ifndef NDEBUG
- if (auto *I = dyn_cast<Instruction>(Incoming))
- assert(DT->dominates(I, ICmp) && "Should be a unique loop dominating value!");
-#endif
-
- const SCEV *IncomingS = SE->getSCEV(Incoming);
-
- if (!NewLHS && IncomingS == InvariantLHS)
- NewLHS = Incoming;
- if (!NewRHS && IncomingS == InvariantRHS)
- NewRHS = Incoming;
- }
-
- if (!NewLHS || !NewRHS)
- // We could not find an existing value to replace either LHS or RHS.
- // Generating new instructions has subtler tradeoffs, so avoid doing that
- // for now.
- return false;
-}
-#endif
-
-bool SimplifyIndvar::makeIVComparisonInvariant(ICmpInst *ICmp,
- Value *IVOperand) {
- unsigned IVOperIdx = 0;
- ICmpInst::Predicate Pred = ICmp->getPredicate();
- if (IVOperand != ICmp->getOperand(0)) {
- // Swapped
- assert(IVOperand == ICmp->getOperand(1) && "Can't find IVOperand");
- IVOperIdx = 1;
- Pred = ICmpInst::getSwappedPredicate(Pred);
- }
-
- // Get the SCEVs for the ICmp operands (in the specific context of the
- // current loop)
- Loop *ICmpLoop = LI->getLoopFor(ICmp->getParent());
- const SCEV *S = SE->getSCEVAtScope(ICmp->getOperand(IVOperIdx), ICmpLoop);
- const SCEV *X = SE->getSCEVAtScope(ICmp->getOperand(1 - IVOperIdx), ICmpLoop);
-
- ICmpInst::Predicate InvariantPredicate;
- const SCEV *InvariantLHS, *InvariantRHS;
-
- if (!isa<PHINode>(IVOperand))
- return false;
- if (!SE->isLoopInvariantPredicate(Pred, S, X, L, InvariantPredicate,
- InvariantLHS, InvariantRHS))
- return false;
-
- // Rewrite the comparison to a loop invariant comparison if it can be done
- // cheaply, where cheaply means "we don't need to emit any new
- // instructions".
-
- Value *NewLHS = nullptr, *NewRHS = nullptr;
-
-#if 1
- const Instruction *At = L->getLoopPreheader()->getTerminator();
- auto *PN = cast<PHINode>(IVOperand);
-#if 0
- SE->getSCEV(ICmp->getOperand(0));
- SE->getSCEV(ICmp->getOperand(1));
-
- for (unsigned i = 0, e = PN->getNumIncomingValues();
- i != e;
- ++i) {
- // If this is a value incoming from the backedge, then it cannot be a loop
- // invariant value (since we know that IVOperand is an induction variable).
- if (L->contains(PN->getIncomingBlock(i)))
- continue;
- SE->getSCEV(PN->getIncomingValue(i));
- }
-#endif
-
- SCEVExpander Rewriter(*SE, SE->getDataLayout(), "indvars");
- NewLHS = Rewriter.getExactExistingExpansion(InvariantLHS, At,
- ICmpLoop);
- NewRHS = Rewriter.getExactExistingExpansion(InvariantRHS, At,
- ICmpLoop);
- if (NewLHS)
- dbgs() << "expand " << InvariantLHS << " as " << *NewLHS << "\n";
- if (NewRHS)
- dbgs() << "expand " << InvariantRHS << " as " << *NewRHS << "\n";
-
-#else
- if (S == InvariantLHS || X == InvariantLHS)
- NewLHS =
- ICmp->getOperand(S == InvariantLHS ? IVOperIdx : (1 - IVOperIdx));
-
- if (S == InvariantRHS || X == InvariantRHS)
- NewRHS =
- ICmp->getOperand(S == InvariantRHS ? IVOperIdx : (1 - IVOperIdx));
-
- auto *PN = cast<PHINode>(IVOperand);
- for (unsigned i = 0, e = PN->getNumIncomingValues();
- i != e && (!NewLHS || !NewRHS);
- ++i) {
-
- // If this is a value incoming from the backedge, then it cannot be a loop
- // invariant value (since we know that IVOperand is an induction variable).
- if (L->contains(PN->getIncomingBlock(i)))
- continue;
-
- // NB! This following assert does not fundamentally have to be true, but
- // it is true today given how SCEV analyzes induction variables.
- // Specifically, today SCEV will *not* recognize %iv as an induction
- // variable in the following case:
- //
- // define void @f(i32 %k) {
- // entry:
- // br i1 undef, label %r, label %l
- //
- // l:
- // %k.inc.l = add i32 %k, 1
- // br label %loop
- //
- // r:
- // %k.inc.r = add i32 %k, 1
- // br label %loop
- //
- // loop:
- // %iv = phi i32 [ %k.inc.l, %l ], [ %k.inc.r, %r ], [ %iv.inc, %loop ]
- // %iv.inc = add i32 %iv, 1
- // br label %loop
- // }
- //
- // but if it starts to, at some point, then the assertion below will have
- // to be changed to a runtime check.
-
- Value *Incoming = PN->getIncomingValue(i);
-
-#ifndef NDEBUG
- if (auto *I = dyn_cast<Instruction>(Incoming))
- assert(DT->dominates(I, ICmp) && "Should be a unique loop dominating value!");
-#endif
-
- const SCEV *IncomingS = SE->getSCEV(Incoming);
-
- if (!NewLHS && IncomingS == InvariantLHS)
- NewLHS = Incoming;
- if (!NewRHS && IncomingS == InvariantRHS)
- NewRHS = Incoming;
- }
-#endif
-
- if (!NewLHS || !NewRHS)
- // We could not find an existing value to replace either LHS or RHS.
- // Generating new instructions has subtler tradeoffs, so avoid doing that
- // for now.
- return false;
-
- DEBUG(dbgs() << "INDVARS: Simplified comparison: " << *ICmp << '\n');
- ICmp->setPredicate(InvariantPredicate);
- ICmp->setOperand(0, NewLHS);
- ICmp->setOperand(1, NewRHS);
- return true;
-}
-
/// SimplifyIVUsers helper for eliminating useless
/// comparisons against an induction variable.
void SimplifyIndvar::eliminateIVComparison(ICmpInst *ICmp, Value *IVOperand) {
@@ -415,6 +180,9 @@ void SimplifyIndvar::eliminateIVComparis
const SCEV *S = SE->getSCEVAtScope(ICmp->getOperand(IVOperIdx), ICmpLoop);
const SCEV *X = SE->getSCEVAtScope(ICmp->getOperand(1 - IVOperIdx), ICmpLoop);
+ ICmpInst::Predicate InvariantPredicate;
+ const SCEV *InvariantLHS, *InvariantRHS;
+
// If the condition is always true or always false, replace it with
// a constant value.
if (SE->isKnownPredicate(Pred, S, X)) {
@@ -425,8 +193,85 @@ void SimplifyIndvar::eliminateIVComparis
ICmp->replaceAllUsesWith(ConstantInt::getFalse(ICmp->getContext()));
DeadInsts.emplace_back(ICmp);
DEBUG(dbgs() << "INDVARS: Eliminated comparison: " << *ICmp << '\n');
- } else if (makeIVComparisonInvariant(ICmp, IVOperand)) {
- // fallthrough to end of function
+ } else if (isa<PHINode>(IVOperand) &&
+ SE->isLoopInvariantPredicate(Pred, S, X, L, InvariantPredicate,
+ InvariantLHS, InvariantRHS)) {
+
+ // Rewrite the comparison to a loop invariant comparison if it can be done
+ // cheaply, where cheaply means "we don't need to emit any new
+ // instructions".
+
+ Value *NewLHS = nullptr, *NewRHS = nullptr;
+
+ if (S == InvariantLHS || X == InvariantLHS)
+ NewLHS =
+ ICmp->getOperand(S == InvariantLHS ? IVOperIdx : (1 - IVOperIdx));
+
+ if (S == InvariantRHS || X == InvariantRHS)
+ NewRHS =
+ ICmp->getOperand(S == InvariantRHS ? IVOperIdx : (1 - IVOperIdx));
+
+ auto *PN = cast<PHINode>(IVOperand);
+ for (unsigned i = 0, e = PN->getNumIncomingValues();
+ i != e && (!NewLHS || !NewRHS);
+ ++i) {
+
+ // If this is a value incoming from the backedge, then it cannot be a loop
+ // invariant value (since we know that IVOperand is an induction variable).
+ if (L->contains(PN->getIncomingBlock(i)))
+ continue;
+
+ // NB! This following assert does not fundamentally have to be true, but
+ // it is true today given how SCEV analyzes induction variables.
+ // Specifically, today SCEV will *not* recognize %iv as an induction
+ // variable in the following case:
+ //
+ // define void @f(i32 %k) {
+ // entry:
+ // br i1 undef, label %r, label %l
+ //
+ // l:
+ // %k.inc.l = add i32 %k, 1
+ // br label %loop
+ //
+ // r:
+ // %k.inc.r = add i32 %k, 1
+ // br label %loop
+ //
+ // loop:
+ // %iv = phi i32 [ %k.inc.l, %l ], [ %k.inc.r, %r ], [ %iv.inc, %loop ]
+ // %iv.inc = add i32 %iv, 1
+ // br label %loop
+ // }
+ //
+ // but if it starts to, at some point, then the assertion below will have
+ // to be changed to a runtime check.
+
+ Value *Incoming = PN->getIncomingValue(i);
+
+#ifndef NDEBUG
+ if (auto *I = dyn_cast<Instruction>(Incoming))
+ assert(DT->dominates(I, ICmp) && "Should be a unique loop dominating value!");
+#endif
+
+ const SCEV *IncomingS = SE->getSCEV(Incoming);
+
+ if (!NewLHS && IncomingS == InvariantLHS)
+ NewLHS = Incoming;
+ if (!NewRHS && IncomingS == InvariantRHS)
+ NewRHS = Incoming;
+ }
+
+ if (!NewLHS || !NewRHS)
+ // We could not find an existing value to replace either LHS or RHS.
+ // Generating new instructions has subtler tradeoffs, so avoid doing that
+ // for now.
+ return;
+
+ DEBUG(dbgs() << "INDVARS: Simplified comparison: " << *ICmp << '\n');
+ ICmp->setPredicate(InvariantPredicate);
+ ICmp->setOperand(0, NewLHS);
+ ICmp->setOperand(1, NewRHS);
} else if (ICmpInst::isSigned(OriginalPred) &&
SE->isKnownNonNegative(S) && SE->isKnownNonNegative(X)) {
// If we were unable to make anything above, all we can is to canonicalize
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