6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-07-25 13:24:46 +00:00
Code Issues Projects Releases Wiki Activity

fix a bug Anders ran into where scalarrepl would crash when promoting

Browse Source 
a union containing a vector and an array whose elements were smaller than
the vector elements.  this means we need to compile the load of the 
array elements into an extract element plus a truncate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47752 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
2008-02-29 07:12:06 +00:00
parent 800de31776
commit 9d34c4d678
2 changed files with 84 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

125
lib/Transforms/Scalar/ScalarReplAggregates.cpp
View File

@@ -1154,70 +1154,81 @@ Value *SROA::ConvertUsesOfLoadToScalar(LoadInst *LI, AllocaInst *NewAI,
// We win, no conversion needed.
return NV;
}
// If the result type of the 'union' is a pointer, then this must be ptr->ptr
// cast. Anything else would result in NV being an integer.
if (isa<PointerType>(NV->getType())) {
assert(isa<PointerType>(LI->getType()));
return new BitCastInst(NV, LI->getType(), LI->getName(), LI);
}
if (const VectorType *PTy = dyn_cast<VectorType>(NV->getType())) {
if (const VectorType *VTy = dyn_cast<VectorType>(NV->getType())) {
// If the result alloca is a vector type, this is either an element
// access or a bitcast to another vector type.
if (isa<VectorType>(LI->getType())) {
NV = new BitCastInst(NV, LI->getType(), LI->getName(), LI);
} else {
// Must be an element access.
const TargetData &TD = getAnalysis<TargetData>();
unsigned Elt = Offset/TD.getABITypeSizeInBits(PTy->getElementType());
NV = new ExtractElementInst(NV, ConstantInt::get(Type::Int32Ty, Elt),
"tmp", LI);
if (isa<VectorType>(LI->getType()))
return new BitCastInst(NV, LI->getType(), LI->getName(), LI);
// Otherwise it must be an element access.
const TargetData &TD = getAnalysis<TargetData>();
unsigned Elt = 0;
if (Offset) {
unsigned EltSize = TD.getABITypeSizeInBits(VTy->getElementType());
Elt = Offset/EltSize;
Offset -= EltSize*Elt;
}
} else if (isa<PointerType>(NV->getType())) {
assert(isa<PointerType>(LI->getType()));
// Must be ptr->ptr cast. Anything else would result in NV being
// an integer.
NV = new ExtractElementInst(NV, ConstantInt::get(Type::Int32Ty, Elt),
"tmp", LI);
// If we're done, return this element.
if (NV->getType() == LI->getType() && Offset == 0)
return NV;
}
const IntegerType *NTy = cast<IntegerType>(NV->getType());
// If this is a big-endian system and the load is narrower than the
// full alloca type, we need to do a shift to get the right bits.
int ShAmt = 0;
const TargetData &TD = getAnalysis<TargetData>();
if (TD.isBigEndian()) {
// On big-endian machines, the lowest bit is stored at the bit offset
// from the pointer given by getTypeStoreSizeInBits. This matters for
// integers with a bitwidth that is not a multiple of 8.
ShAmt = TD.getTypeStoreSizeInBits(NTy) -
TD.getTypeStoreSizeInBits(LI->getType()) - Offset;
} else {
ShAmt = Offset;
}
// Note: we support negative bitwidths (with shl) which are not defined.
// We do this to support (f.e.) loads off the end of a structure where
// only some bits are used.
if (ShAmt > 0 && (unsigned)ShAmt < NTy->getBitWidth())
NV = BinaryOperator::createLShr(NV,
ConstantInt::get(NV->getType(),ShAmt),
LI->getName(), LI);
else if (ShAmt < 0 && (unsigned)-ShAmt < NTy->getBitWidth())
NV = BinaryOperator::createShl(NV,
ConstantInt::get(NV->getType(),-ShAmt),
LI->getName(), LI);
// Finally, unconditionally truncate the integer to the right width.
unsigned LIBitWidth = TD.getTypeSizeInBits(LI->getType());
if (LIBitWidth < NTy->getBitWidth())
NV = new TruncInst(NV, IntegerType::get(LIBitWidth),
LI->getName(), LI);
// If the result is an integer, this is a trunc or bitcast.
if (isa<IntegerType>(LI->getType())) {
// Should be done.
} else if (LI->getType()->isFloatingPoint()) {
// Just do a bitcast, we know the sizes match up.
NV = new BitCastInst(NV, LI->getType(), LI->getName(), LI);
} else {
const IntegerType *NTy = cast<IntegerType>(NV->getType());
// If this is a big-endian system and the load is narrower than the
// full alloca type, we need to do a shift to get the right bits.
int ShAmt = 0;
const TargetData &TD = getAnalysis<TargetData>();
if (TD.isBigEndian()) {
// On big-endian machines, the lowest bit is stored at the bit offset
// from the pointer given by getTypeStoreSizeInBits. This matters for
// integers with a bitwidth that is not a multiple of 8.
ShAmt = TD.getTypeStoreSizeInBits(NTy) -
TD.getTypeStoreSizeInBits(LI->getType()) - Offset;
} else {
ShAmt = Offset;
}
// Note: we support negative bitwidths (with shl) which are not defined.
// We do this to support (f.e.) loads off the end of a structure where
// only some bits are used.
if (ShAmt > 0 && (unsigned)ShAmt < NTy->getBitWidth())
NV = BinaryOperator::createLShr(NV,
ConstantInt::get(NV->getType(),ShAmt),
LI->getName(), LI);
else if (ShAmt < 0 && (unsigned)-ShAmt < NTy->getBitWidth())
NV = BinaryOperator::createShl(NV,
ConstantInt::get(NV->getType(),-ShAmt),
LI->getName(), LI);
// Finally, unconditionally truncate the integer to the right width.
unsigned LIBitWidth = TD.getTypeSizeInBits(LI->getType());
if (LIBitWidth < NTy->getBitWidth())
NV = new TruncInst(NV, IntegerType::get(LIBitWidth),
LI->getName(), LI);
// If the result is an integer, this is a trunc or bitcast.
if (isa<IntegerType>(LI->getType())) {
assert(NV->getType() == LI->getType() && "Truncate wasn't enough?");
} else if (LI->getType()->isFloatingPoint()) {
// Just do a bitcast, we know the sizes match up.
NV = new BitCastInst(NV, LI->getType(), LI->getName(), LI);
} else {
// Otherwise must be a pointer.
NV = new IntToPtrInst(NV, LI->getType(), LI->getName(), LI);
}
// Otherwise must be a pointer.
NV = new IntToPtrInst(NV, LI->getType(), LI->getName(), LI);
}
assert(NV->getType() == LI->getType() && "Didn't convert right?");
return NV;
}