diff options
| -rw-r--r-- | lib/Analysis/InstructionSimplify.cpp | 25 | ||||
| -rw-r--r-- | test/Transforms/InstSimplify/compare.ll | 13 |
2 files changed, 33 insertions, 5 deletions
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp index 88a2c53e80..9b0ce1113a 100644 --- a/lib/Analysis/InstructionSimplify.cpp +++ b/lib/Analysis/InstructionSimplify.cpp @@ -1520,6 +1520,15 @@ static Value *ExtractEquivalentCondition(Value *V, CmpInst::Predicate Pred, return 0; } +/// stripPointerAdjustments - This is like Value::stripPointerCasts, but also +/// removes inbounds gep operations, regardless of their indices. +static Value *stripPointerAdjustments(Value *V) { + if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) + if (GEP->isInBounds()) + return stripPointerAdjustments(GEP->getOperand(0)->stripPointerCasts()); + return V; +} + /// SimplifyICmpInst - Given operands for an ICmpInst, see if we can /// fold the result. If not, this returns null. static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, @@ -1595,10 +1604,18 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, Value *RHSPtr = RHS->stripPointerCasts(); if (LHSPtr == RHSPtr) return ConstantInt::get(ITy, CmpInst::isTrueWhenEqual(Pred)); - if (isa<AllocaInst>(LHSPtr) && (isa<GlobalValue>(RHSPtr) || - isa<AllocaInst>(RHSPtr) || - isa<ConstantPointerNull>(RHSPtr))) - return ConstantInt::get(ITy, CmpInst::isFalseWhenEqual(Pred)); + + // Be more aggressive about stripping pointer adjustments when checking a + // comparison of an alloca address to another object. We can rip off all + // inbounds GEP operations, even if they are variable. + LHSPtr = stripPointerAdjustments(LHSPtr); + if (isa<AllocaInst>(LHSPtr)) { + RHSPtr = stripPointerAdjustments(RHSPtr); + if (LHSPtr != RHSPtr && + (isa<GlobalValue>(RHSPtr) || isa<AllocaInst>(RHSPtr) || + isa<ConstantPointerNull>(RHSPtr))) + return ConstantInt::get(ITy, CmpInst::isFalseWhenEqual(Pred)); + } // If we are comparing with zero then try hard since this is a common case. if (match(RHS, m_Zero())) { diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll index 92b8fc7e3a..f22ac46397 100644 --- a/test/Transforms/InstSimplify/compare.ll +++ b/test/Transforms/InstSimplify/compare.ll @@ -446,9 +446,20 @@ define <2 x i1> @vectorselect1(<2 x i1> %cond) { ; CHECK: ret <2 x i1> %cond } -define <2 x i1> @vectorselectcrash(i32 %arg1) { ; PR11948 +; PR11948 +define <2 x i1> @vectorselectcrash(i32 %arg1) { %tobool40 = icmp ne i32 %arg1, 0 %cond43 = select i1 %tobool40, <2 x i16> <i16 -5, i16 66>, <2 x i16> <i16 46, i16 1> %cmp45 = icmp ugt <2 x i16> %cond43, <i16 73, i16 21> ret <2 x i1> %cmp45 } + +; PR12013 +define i1 @alloca_compare(i64 %idx) { + %sv = alloca { i32, i32, [124 x i32] } + %1 = getelementptr inbounds { i32, i32, [124 x i32] }* %sv, i32 0, i32 2, i64 %idx + %2 = icmp eq i32* %1, null + ret i1 %2 + ; CHECK: alloca_compare + ; CHECK: ret i1 false +} |