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tweaks suggested by Duncan 

llvm-svn: 92824
This commit is contained in:
Chris Lattner 2010-01-06 05:32:15 +00:00
parent 70aa5391dd
commit 4339f2abdb
1 changed files with 7 additions and 7 deletions
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14
llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
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@ -162,7 +162,7 @@ Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI,
/// inst(trunc(x),trunc(y)), which only makes sense if x and y can be /// inst(trunc(x),trunc(y)), which only makes sense if x and y can be
/// efficiently truncated. /// efficiently truncated.
/// ///
/// If CastOpc is zext, we are asking if the low bits of the value can bit /// If CastOpc is zext, we are asking if the low bits of the value can be
/// computed in a larger type, which is then and'd to get the final result. /// computed in a larger type, which is then and'd to get the final result.
static bool CanEvaluateInDifferentType(Value *V, const Type *Ty, static bool CanEvaluateInDifferentType(Value *V, const Type *Ty,
unsigned CastOpc, unsigned CastOpc,
@ -295,9 +295,9 @@ static bool CanEvaluateInDifferentType(Value *V, const Type *Ty,
/// CanEvaluateSExtd - Return true if we can take the specified value /// CanEvaluateSExtd - Return true if we can take the specified value
/// and return it as type Ty without inserting any new casts and without /// and return it as type Ty without inserting any new casts and without
/// changing the computed value of the common low bits. This is used by code /// changing the value of the common low bits. This is used by code that tries
/// that tries to promote integer operations to a wider types will allow us to /// to promote integer operations to a wider types will allow us to eliminate
/// eliminate the extension. /// the extension.
/// ///
/// This returns 0 if we can't do this or the number of sign bits that would be /// This returns 0 if we can't do this or the number of sign bits that would be
/// set if we can. For example, CanEvaluateSExtd(i16 1, i64) would return 63, /// set if we can. For example, CanEvaluateSExtd(i16 1, i64) would return 63,
@ -622,14 +622,14 @@ Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) {
// Because this is a sign extension, we can always transform it by inserting // Because this is a sign extension, we can always transform it by inserting
// two new shifts (to do the extension). However, this is only profitable // two new shifts (to do the extension). However, this is only profitable
// if we've eliminated two or more casts from the input. If we know the // if we've eliminated two or more casts from the input. If we know the
// result will be sign-extendy enough to not require these shifts, we can // result will be sign-extended enough to not require these shifts, we can
// always do the transformation. // always do the transformation.
if (NumCastsRemoved < 2 && if (NumCastsRemoved < 2 &&
NumBitsSExt <= DestBitSize-SrcBitSize) NumBitsSExt <= DestBitSize-SrcBitSize)
return 0; return 0;
// Okay, we can transform this! Insert the new expression now. // Okay, we can transform this! Insert the new expression now.
DEBUG(errs() << "ICE: EvaluateInDifferentType converting expression type" DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
" to avoid sign extend: " << CI); " to avoid sign extend: " << CI);
Value *Res = EvaluateInDifferentType(Src, DestTy, true); Value *Res = EvaluateInDifferentType(Src, DestTy, true);
assert(Res->getType() == DestTy); assert(Res->getType() == DestTy);
@ -645,7 +645,7 @@ Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) {
} }
} }
DEBUG(errs() << "ICE: EvaluateInDifferentType converting expression type" DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
" to avoid cast: " << CI); " to avoid cast: " << CI);
Value *Res = EvaluateInDifferentType(Src, DestTy, false); Value *Res = EvaluateInDifferentType(Src, DestTy, false);
assert(Res->getType() == DestTy); assert(Res->getType() == DestTy);