On behalf of Alexandros Lamprineas:

LLVM targeting aarch64 doesn't correctly produce aligned accesses for non-aligned
data at -O0/fast-isel (-mno-unaligned-access).
The root cause seems to be in fast-isel not producing unaligned access correctly
for -mno-unaligned-access.

The patch just aborts fast-isel for loads and stores when -mno-unaligned-access is
present. 
The regression test is updated to check this new test case (-mno-unaligned-access 
together with fast-isel).

Differential Revision: http://reviews.llvm.org/D10360



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239732 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evgeny Astigeevich 2015-06-15 15:48:44 +00:00
parent 4f9d346fa0
commit 2ecc72cc58
2 changed files with 7 additions and 0 deletions

View File

@ -1678,6 +1678,9 @@ unsigned AArch64FastISel::emitAnd_ri(MVT RetVT, unsigned LHSReg, bool LHSIsKill,
unsigned AArch64FastISel::emitLoad(MVT VT, MVT RetVT, Address Addr,
bool WantZExt, MachineMemOperand *MMO) {
if(!TLI.allowsMisalignedMemoryAccesses(VT))
return 0;
// Simplify this down to something we can handle.
if (!simplifyAddress(Addr, VT))
return 0;
@ -1962,6 +1965,9 @@ bool AArch64FastISel::selectLoad(const Instruction *I) {
bool AArch64FastISel::emitStore(MVT VT, unsigned SrcReg, Address Addr,
MachineMemOperand *MMO) {
if(!TLI.allowsMisalignedMemoryAccesses(VT))
return false;
// Simplify this down to something we can handle.
if (!simplifyAddress(Addr, VT))
return false;

View File

@ -1,6 +1,7 @@
; RUN: llc < %s -mtriple=arm64-apple-darwin | FileCheck %s
; RUN: llc < %s -mtriple=arm64-apple-darwin -aarch64-no-strict-align | FileCheck %s
; RUN: llc < %s -mtriple=arm64-apple-darwin -aarch64-strict-align | FileCheck %s --check-prefix=CHECK-STRICT
; RUN: llc < %s -mtriple=arm64-apple-darwin -aarch64-strict-align -fast-isel | FileCheck %s --check-prefix=CHECK-STRICT
define i32 @f0(i32* nocapture %p) nounwind {
; CHECK-STRICT: ldrh [[HIGH:w[0-9]+]], [x0, #2]