AArch64: __va_list.__stack must be 8-byte aligned

The va_start macro for AArch64 must set va_list.__stack to the address
following the last named argument on the stack, rounded up to an alignment
of 8 bytes.

llvm-svn: 201797
This commit is contained in:
Oliver Stannard 2014-02-20 17:19:26 +00:00
parent 7cf2bebfc4
commit 7b2f2fba7f
2 changed files with 45 additions and 1 deletions

View File

@ -26,6 +26,7 @@
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
@ -1282,7 +1283,8 @@ AArch64TargetLowering::SaveVarArgRegisters(CCState &CCInfo, SelectionDAG &DAG,
FuncInfo->setVariadicFPRSize(FPRSaveSize);
}
int StackIdx = MFI->CreateFixedObject(8, CCInfo.getNextStackOffset(), true);
unsigned StackOffset = RoundUpToAlignment(CCInfo.getNextStackOffset(), 8);
int StackIdx = MFI->CreateFixedObject(8, StackOffset, true);
FuncInfo->setVariadicStackIdx(StackIdx);
FuncInfo->setVariadicGPRIdx(GPRIdx);

View File

@ -197,3 +197,45 @@ define void @test_va_copy() {
; CHECK: ret
; CHECK-NOFP: ret
}
%struct.s_3i = type { i32, i32, i32 }
; This checks that, if the last named argument is not a multiple of 8 bytes,
; and is allocated on the stack, that __va_list.__stack is initialised to the
; first 8-byte aligned location above it.
define void @test_va_odd_struct_on_stack(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f, i32 %g, [1 x i64], %struct.s_3i* byval nocapture readnone align 4 %h, ...) {
; CHECK-LABEL: test_va_odd_struct_on_stack:
; CHECK: sub sp, sp, #128
; CHECK: mov x[[FPRBASE:[0-9]+]], sp
; CHECK: str q7, [x[[FPRBASE]], #112]
; CHECK-NOT: str x{{[0-9]+}},
; CHECK-NOFP-NOT: str q7,
; CHECK-NOT: str x7,
; Omit the middle ones
; CHECK: str q0, [sp]
%addr = bitcast %va_list* @var to i8*
call void @llvm.va_start(i8* %addr)
; CHECK: add x[[VA_LIST:[0-9]+]], {{x[0-9]+}}, #:lo12:var
; CHECK: movn [[VR_OFFS:w[0-9]+]], #127
; CHECK: str [[VR_OFFS]], [x[[VA_LIST]], #28]
; CHECK: str wzr, [x[[VA_LIST]], #24]
; CHECK: add [[VR_TOP:x[0-9]+]], x[[FPRBASE]], #128
; CHECK: str [[VR_TOP]], [x[[VA_LIST]], #16]
; This constant would be #140 if it was not 8-byte aligned
; CHECK: add [[STACK:x[0-9]+]], sp, #144
; CHECK: str [[STACK]], [{{x[0-9]+}}, #:lo12:var]
; CHECK-NOFP: add x[[VA_LIST:[0-9]+]], {{x[0-9]+}}, #:lo12:var
; This constant would be #12 if it was not 8-byte aligned
; CHECK-NOFP: add [[STACK:x[0-9]+]], sp, #16
; CHECK-NOFP: str [[STACK]], [{{x[0-9]+}}, #:lo12:var]
; CHECK-NOFP: str wzr, [x[[VA_LIST]], #28]
; CHECK-NOFP: str wzr, [x[[VA_LIST]], #24]
ret void
}