64-bit (MMX) vectors do not need restrictive alignment.

128-bit vectors need it only when SSE is on.

llvm-svn: 46890
This commit is contained in:
Dale Johannesen 2008-02-08 19:48:20 +00:00
parent d74057fa87
commit 36c2967d89
1 changed files with 4 additions and 6 deletions

View File

@ -704,9 +704,6 @@ static void getMaxByValAlign(const Type *Ty, unsigned &MaxAlign) {
if (const VectorType *VTy = dyn_cast<VectorType>(Ty)) {
if (VTy->getBitWidth() == 128)
MaxAlign = 16;
else if (VTy->getBitWidth() == 64)
if (MaxAlign < 8)
MaxAlign = 8;
} else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
unsigned EltAlign = 0;
getMaxByValAlign(ATy->getElementType(), EltAlign);
@ -727,13 +724,14 @@ static void getMaxByValAlign(const Type *Ty, unsigned &MaxAlign) {
/// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
/// function arguments in the caller parameter area. For X86, aggregates
/// that contains are placed at 16-byte boundaries while the rest are at
/// 4-byte boundaries.
/// that contain SSE vectors are placed at 16-byte boundaries while the rest
/// are at 4-byte boundaries.
unsigned X86TargetLowering::getByValTypeAlignment(const Type *Ty) const {
if (Subtarget->is64Bit())
return getTargetData()->getABITypeAlignment(Ty);
unsigned Align = 4;
getMaxByValAlign(Ty, Align);
if (Subtarget->hasSSE1())
getMaxByValAlign(Ty, Align);
return Align;
}