use instructionsimplify instead of a weak clone of ad-hoc folding stuff.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86616 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-11-09 23:00:14 +00:00
parent 3f51147d44
commit 9819ef7742

View File

@ -17,6 +17,7 @@
#include "llvm/LLVMContext.h"
#include "llvm/Pass.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
@ -203,7 +204,6 @@ static void RemovePredecessorAndSimplify(BasicBlock *BB, BasicBlock *Pred,
// Remove the entries for Pred from the PHI nodes in BB, but do not simplify
// them down. This will leave us with single entry phi nodes and other phis
// that can be removed.
//BB->removePredecessor(Pred, true);
BB->removePredecessor(Pred, true);
WeakVH PhiIt = &BB->front();
@ -266,26 +266,6 @@ void JumpThreading::FindLoopHeaders(Function &F) {
LoopHeaders.insert(const_cast<BasicBlock*>(Edges[i].second));
}
/// GetResultOfComparison - Given an icmp/fcmp predicate and the left and right
/// hand sides of the compare instruction, try to determine the result. If the
/// result can not be determined, a null pointer is returned.
static Constant *GetResultOfComparison(CmpInst::Predicate pred,
Value *LHS, Value *RHS) {
if (Constant *CLHS = dyn_cast<Constant>(LHS))
if (Constant *CRHS = dyn_cast<Constant>(RHS))
return ConstantExpr::getCompare(pred, CLHS, CRHS);
if (LHS == RHS)
if (isa<IntegerType>(LHS->getType()) || isa<PointerType>(LHS->getType())) {
if (ICmpInst::isTrueWhenEqual(pred))
return ConstantInt::getTrue(LHS->getContext());
else
return ConstantInt::getFalse(LHS->getContext());
}
return 0;
}
/// ComputeValueKnownInPredecessors - Given a basic block BB and a value V, see
/// if we can infer that the value is a known ConstantInt in any of our
/// predecessors. If so, return the known list of value and pred BB in the
@ -374,7 +354,7 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB,PredValueInfo &Result){
Value *LHS = PN->getIncomingValue(i);
Value *RHS = Cmp->getOperand(1)->DoPHITranslation(BB, PredBB);
Constant *Res = GetResultOfComparison(Cmp->getPredicate(), LHS, RHS);
Value *Res = SimplifyCompare(Cmp->getPredicate(), LHS, RHS);
if (Res == 0) continue;
if (isa<UndefValue>(Res))