ARM byval: when type alignment is bigger than ABI alignment, instead of
disabling byval, we set realign to true.
It will perform an aligned alloca, and call memcpy to copy the byval
argument to the local variable.
Change the size threshold back to 64 bytes.
rdar://12596507
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167440 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index 9060337..2229260 100644
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -3221,16 +3221,15 @@
// Support byval for ARM.
// The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at most 8-byte.
- // Byval can't handle the case where type alignment is bigger than ABI alignment.
- // We also increase the threshold for byval due to its overhead.
+ // We realign the indirect argument if type alignment is bigger than ABI alignment.
uint64_t ABIAlign = 4;
uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
getABIKind() == ARMABIInfo::AAPCS)
ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
- if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64*8) &&
- TyAlign <= ABIAlign) {
- return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
+ if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
+ return ABIArgInfo::getIndirect(0, /*ByVal=*/true,
+ /*Realign=*/TyAlign <= ABIAlign ? false : true);
}
// Otherwise, pass by coercing to a structure of the appropriate size.