make scalar conversion handle stores of first class

aggregate values.  loads are not yet handled (coming
soon to an sroa near you).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63649 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-02-03 19:30:11 +00:00
parent 43f07fb6c3
commit 9b872db775
2 changed files with 50 additions and 22 deletions

View File

@ -130,8 +130,8 @@ namespace {
void ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset);
Value *ConvertUsesOfLoadToScalar(LoadInst *LI, AllocaInst *NewAI,
uint64_t Offset);
Value *ConvertUsesOfStoreToScalar(Value *StoredVal, AllocaInst *NewAI,
uint64_t Offset, Instruction *InsertPt);
Value *ConvertScalar_InsertValue(Value *StoredVal, Value *ExistingVal,
uint64_t Offset, Instruction *InsertPt);
static Instruction *isOnlyCopiedFromConstantGlobal(AllocationInst *AI);
};
}
@ -1326,8 +1326,9 @@ void SROA::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset) {
if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
assert(SI->getOperand(0) != Ptr && "Consistency error!");
new StoreInst(ConvertUsesOfStoreToScalar(SI->getOperand(0), NewAI,
Offset, SI), NewAI, SI);
Value *Old = new LoadInst(NewAI, NewAI->getName()+".in", SI);
Value *New = ConvertScalar_InsertValue(SI->getOperand(0), Old, Offset,SI);
new StoreInst(New, NewAI, SI);
SI->eraseFromParent();
continue;
}
@ -1363,8 +1364,10 @@ void SROA::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset) {
for (unsigned i = 1; i != NumBytes; ++i)
APVal |= APVal << 8;
new StoreInst(ConvertUsesOfStoreToScalar(ConstantInt::get(APVal), NewAI,
Offset, MSI), NewAI, MSI);
Value *Old = new LoadInst(NewAI, NewAI->getName()+".in", MSI);
Value *New = ConvertScalar_InsertValue(ConstantInt::get(APVal), Old,
Offset, MSI);
new StoreInst(New, NewAI, MSI);
MSI->eraseFromParent();
continue;
}
@ -1464,26 +1467,23 @@ Value *SROA::ConvertUsesOfLoadToScalar(LoadInst *LI, AllocaInst *NewAI,
}
/// ConvertUsesOfStoreToScalar - Convert the specified store to a load+store
/// pair of the new alloca directly, returning the value that should be stored
/// to the alloca. This happens when we are converting an "integer union" to a
/// ConvertScalar_InsertValue - Insert the value "SV" into the existing integer
/// or vector value "Old" at the offset specified by Offset.
///
/// This happens when we are converting an "integer union" to a
/// single integer scalar, or when we are converting a "vector union" to a
/// vector with insert/extractelement instructions.
///
/// Offset is an offset from the original alloca, in bits that need to be
/// shifted to the right. By the end of this, there should be no uses of Ptr.
Value *SROA::ConvertUsesOfStoreToScalar(Value *SV, AllocaInst *NewAI,
uint64_t Offset, Instruction *IP) {
/// shifted to the right.
Value *SROA::ConvertScalar_InsertValue(Value *SV, Value *Old,
uint64_t Offset, Instruction *IP) {
// Convert the stored type to the actual type, shift it left to insert
// then 'or' into place.
const Type *AllocaType = NewAI->getType()->getElementType();
if (SV->getType() == AllocaType && Offset == 0)
return SV;
const Type *AllocaType = Old->getType();
if (const VectorType *VTy = dyn_cast<VectorType>(AllocaType)) {
Value *Old = new LoadInst(NewAI, NewAI->getName()+".in", IP);
// If the result alloca is a vector type, this is either an element
// access or a bitcast to another vector type.
if (isa<VectorType>(SV->getType())) {
@ -1501,13 +1501,29 @@ Value *SROA::ConvertUsesOfStoreToScalar(Value *SV, AllocaInst *NewAI,
}
return SV;
}
Value *Old = new LoadInst(NewAI, NewAI->getName()+".in", IP);
// If SV is a first-class aggregate value, insert each value recursively.
if (const StructType *ST = dyn_cast<StructType>(SV->getType())) {
const StructLayout &Layout = *TD->getStructLayout(ST);
for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) {
Value *Elt = ExtractValueInst::Create(SV, i, "tmp", IP);
Old = ConvertScalar_InsertValue(Elt, Old,
Offset+Layout.getElementOffset(i), IP);
}
return Old;
}
if (const ArrayType *AT = dyn_cast<ArrayType>(SV->getType())) {
uint64_t EltSize = TD->getTypePaddedSizeInBits(AT->getElementType());
for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) {
Value *Elt = ExtractValueInst::Create(SV, i, "tmp", IP);
Old = ConvertScalar_InsertValue(Elt, Old, Offset+i*EltSize, IP);
}
return Old;
}
// If SV is a float, convert it to the appropriate integer type.
// If it is a pointer, do the same, and also handle ptr->ptr casts
// here.
// If it is a pointer, do the same.
unsigned SrcWidth = TD->getTypeSizeInBits(SV->getType());
unsigned DestWidth = TD->getTypeSizeInBits(AllocaType);
unsigned SrcStoreWidth = TD->getTypeStoreSizeInBits(SV->getType());

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@ -0,0 +1,12 @@
; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis
; Make sure that SROA "scalar conversion" can handle first class aggregates.
define i64 @test({i32, i32} %A) {
%X = alloca i64
%Y = bitcast i64* %X to {i32,i32}*
store {i32,i32} %A, {i32,i32}* %Y
%Q = load i64* %X
ret i64 %Q
}