Add three new helper routines, getNoopOrZeroExtend,

getNoopOrSignExtend, and getTruncateOrNoop. These are similar
to getTruncateOrZeroExtend etc., except that they assert that
the conversion is either not widening or narrowing, as
appropriate. These will be used in some upcoming fixes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71632 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2009-05-13 03:46:30 +00:00
parent 7b9486ad43
commit 467c430316
2 changed files with 62 additions and 0 deletions
+47
View File
@@ -1807,6 +1807,53 @@ ScalarEvolution::getTruncateOrSignExtend(const SCEVHandle &V,
return getSignExtendExpr(V, Ty);
}
/// getNoopOrZeroExtend - Return a SCEV corresponding to a conversion of the
/// input value to the specified type. If the type must be extended, it is zero
/// extended. The conversion must not be narrowing.
SCEVHandle
ScalarEvolution::getNoopOrZeroExtend(const SCEVHandle &V, const Type *Ty) {
const Type *SrcTy = V->getType();
assert((SrcTy->isInteger() || (TD && isa<PointerType>(SrcTy))) &&
(Ty->isInteger() || (TD && isa<PointerType>(Ty))) &&
"Cannot noop or zero extend with non-integer arguments!");
assert(getTypeSizeInBits(SrcTy) <= getTypeSizeInBits(Ty) &&
"getNoopOrZeroExtend cannot truncate!");
if (getTypeSizeInBits(SrcTy) == getTypeSizeInBits(Ty))
return V; // No conversion
return getZeroExtendExpr(V, Ty);
}
/// getNoopOrSignExtend - Return a SCEV corresponding to a conversion of the
/// input value to the specified type. If the type must be extended, it is sign
/// extended. The conversion must not be narrowing.
SCEVHandle
ScalarEvolution::getNoopOrSignExtend(const SCEVHandle &V, const Type *Ty) {
const Type *SrcTy = V->getType();
assert((SrcTy->isInteger() || (TD && isa<PointerType>(SrcTy))) &&
(Ty->isInteger() || (TD && isa<PointerType>(Ty))) &&
"Cannot noop or sign extend with non-integer arguments!");
assert(getTypeSizeInBits(SrcTy) <= getTypeSizeInBits(Ty) &&
"getNoopOrSignExtend cannot truncate!");
if (getTypeSizeInBits(SrcTy) == getTypeSizeInBits(Ty))
return V; // No conversion
return getSignExtendExpr(V, Ty);
}
/// getTruncateOrNoop - Return a SCEV corresponding to a conversion of the
/// input value to the specified type. The conversion must not be widening.
SCEVHandle
ScalarEvolution::getTruncateOrNoop(const SCEVHandle &V, const Type *Ty) {
const Type *SrcTy = V->getType();
assert((SrcTy->isInteger() || (TD && isa<PointerType>(SrcTy))) &&
(Ty->isInteger() || (TD && isa<PointerType>(Ty))) &&
"Cannot truncate or noop with non-integer arguments!");
assert(getTypeSizeInBits(SrcTy) >= getTypeSizeInBits(Ty) &&
"getTruncateOrNoop cannot extend!");
if (getTypeSizeInBits(SrcTy) == getTypeSizeInBits(Ty))
return V; // No conversion
return getTruncateExpr(V, Ty);
}
/// ReplaceSymbolicValueWithConcrete - This looks up the computed SCEV value for
/// the specified instruction and replaces any references to the symbolic value
/// SymName with the specified value. This is used during PHI resolution.