diff options
| -rw-r--r-- | lib/Transforms/Utils/SimplifyCFG.cpp | 51 | ||||
| -rw-r--r-- | test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll | 9 |
2 files changed, 26 insertions, 34 deletions
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp index d36d9dc..d56bb32 100644 --- a/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/lib/Transforms/Utils/SimplifyCFG.cpp @@ -19,6 +19,7 @@ #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" +#include "llvm/Analysis/ConstantFolding.h" #include "llvm/Analysis/InstructionSimplify.h" #include "llvm/Analysis/TargetTransformInfo.h" #include "llvm/Analysis/ValueTracking.h" @@ -3323,28 +3324,10 @@ static Constant *LookupConstant(Value *V, /// simple instructions such as binary operations where both operands are /// constant or can be replaced by constants from the ConstantPool. Returns the /// resulting constant on success, 0 otherwise. -static Constant *ConstantFold(Instruction *I, - const SmallDenseMap<Value*, Constant*>& ConstantPool) { - if (BinaryOperator *BO = dyn_cast<BinaryOperator>(I)) { - Constant *A = LookupConstant(BO->getOperand(0), ConstantPool); - if (!A) - return 0; - Constant *B = LookupConstant(BO->getOperand(1), ConstantPool); - if (!B) - return 0; - return ConstantExpr::get(BO->getOpcode(), A, B); - } - - if (CmpInst *Cmp = dyn_cast<CmpInst>(I)) { - Constant *A = LookupConstant(I->getOperand(0), ConstantPool); - if (!A) - return 0; - Constant *B = LookupConstant(I->getOperand(1), ConstantPool); - if (!B) - return 0; - return ConstantExpr::getCompare(Cmp->getPredicate(), A, B); - } - +static Constant * +ConstantFold(Instruction *I, + const SmallDenseMap<Value *, Constant *> &ConstantPool, + const DataLayout *DL) { if (SelectInst *Select = dyn_cast<SelectInst>(I)) { Constant *A = LookupConstant(Select->getCondition(), ConstantPool); if (!A) @@ -3356,14 +3339,19 @@ static Constant *ConstantFold(Instruction *I, return 0; } - if (CastInst *Cast = dyn_cast<CastInst>(I)) { - Constant *A = LookupConstant(I->getOperand(0), ConstantPool); - if (!A) + SmallVector<Constant *, 4> COps; + for (unsigned N = 0, E = I->getNumOperands(); N != E; ++N) { + if (Constant *A = LookupConstant(I->getOperand(N), ConstantPool)) + COps.push_back(A); + else return 0; - return ConstantExpr::getCast(Cast->getOpcode(), A, Cast->getDestTy()); } - return 0; + if (CmpInst *Cmp = dyn_cast<CmpInst>(I)) + return ConstantFoldCompareInstOperands(Cmp->getPredicate(), COps[0], + COps[1], DL); + + return ConstantFoldInstOperands(I->getOpcode(), I->getType(), COps, DL); } /// GetCaseResults - Try to determine the resulting constant values in phi nodes @@ -3375,7 +3363,8 @@ GetCaseResults(SwitchInst *SI, ConstantInt *CaseVal, BasicBlock *CaseDest, BasicBlock **CommonDest, - SmallVectorImpl<std::pair<PHINode*,Constant*> > &Res) { + SmallVectorImpl<std::pair<PHINode *, Constant *> > &Res, + const DataLayout *DL) { // The block from which we enter the common destination. BasicBlock *Pred = SI->getParent(); @@ -3394,7 +3383,7 @@ GetCaseResults(SwitchInst *SI, } else if (isa<DbgInfoIntrinsic>(I)) { // Skip debug intrinsic. continue; - } else if (Constant *C = ConstantFold(I, ConstantPool)) { + } else if (Constant *C = ConstantFold(I, ConstantPool, DL)) { // Instruction is side-effect free and constant. ConstantPool.insert(std::make_pair(I, C)); } else { @@ -3718,7 +3707,7 @@ static bool SwitchToLookupTable(SwitchInst *SI, typedef SmallVector<std::pair<PHINode*, Constant*>, 4> ResultsTy; ResultsTy Results; if (!GetCaseResults(SI, CaseVal, CI.getCaseSuccessor(), &CommonDest, - Results)) + Results, TD)) return false; // Append the result from this case to the list for each phi. @@ -3732,7 +3721,7 @@ static bool SwitchToLookupTable(SwitchInst *SI, // Get the resulting values for the default case. SmallVector<std::pair<PHINode*, Constant*>, 4> DefaultResultsList; if (!GetCaseResults(SI, 0, SI->getDefaultDest(), &CommonDest, - DefaultResultsList)) + DefaultResultsList, TD)) return false; for (size_t I = 0, E = DefaultResultsList.size(); I != E; ++I) { PHINode *PHI = DefaultResultsList[I].first; diff --git a/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll b/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll index 71259c9..3687327 100644 --- a/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll +++ b/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll @@ -711,7 +711,7 @@ return: ret i32 %retval.0 } -define i32 @cprop(i32 %x) { +define i32 @cprop(i32 %x, i32 %y) { entry: switch i32 %x, label %sw.default [ i32 1, label %return @@ -727,7 +727,8 @@ sw.bb1: br label %return sw.bb2: %and = and i32 %x, 1 - %tobool = icmp ne i32 %and, 0 + %and.ptr = inttoptr i32 %and to i8* + %tobool = icmp ne i8* %and.ptr, null %cond = select i1 %tobool, i32 -123, i32 456 %sub = sub nsw i32 %x, %cond br label %return @@ -735,13 +736,15 @@ sw.bb2: sw.bb3: %trunc = trunc i32 %x to i8 %sext = sext i8 %trunc to i32 + %select.i = icmp sgt i32 %sext, 0 + %select = select i1 %select.i, i32 %sext, i32 %y br label %return sw.default: br label %return return: - %retval.0 = phi i32 [ 123, %sw.default ], [ %sext, %sw.bb3 ], [ %sub, %sw.bb2 ], [ 42, %sw.bb1 ], [ 5, %entry ] + %retval.0 = phi i32 [ 123, %sw.default ], [ %select, %sw.bb3 ], [ %sub, %sw.bb2 ], [ 42, %sw.bb1 ], [ 5, %entry ] ret i32 %retval.0 ; CHECK-LABEL: @cprop( |