ARM: support stack probe size on Windows on ARM

Now that -mstack-probe-size is piped through to the backend via the function
attribute as on Windows x86, honour the value to permit handling of non-default
values for stack probes.  This is needed /Gs with the clang-cl driver or
-mstack-probe-size with the clang driver when targeting Windows on ARM.

llvm-svn: 227667
This commit is contained in:
Saleem Abdulrasool 2015-01-31 02:26:37 +00:00
parent 33ab83bc4b
commit fb8a66fbc5
2 changed files with 34 additions and 3 deletions

View File

@ -164,9 +164,13 @@ static int sizeOfSPAdjustment(const MachineInstr *MI) {
static bool WindowsRequiresStackProbe(const MachineFunction &MF,
size_t StackSizeInBytes) {
const MachineFrameInfo *MFI = MF.getFrameInfo();
if (MFI->getStackProtectorIndex() > 0)
return StackSizeInBytes >= 4080;
return StackSizeInBytes >= 4096;
const Function *F = MF.getFunction();
unsigned StackProbeSize = (MFI->getStackProtectorIndex() > 0) ? 4080 : 4096;
if (F->hasFnAttribute("stack-probe-size"))
F->getFnAttribute("stack-probe-size")
.getValueAsString()
.getAsInteger(0, StackProbeSize);
return StackSizeInBytes >= StackProbeSize;
}
namespace {

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@ -0,0 +1,27 @@
; RUN: llc -mtriple thumbv7-windows -mcpu cortex-a9 -o - %s \
; RUN: | FileCheck %s -check-prefix CHECK-DEFAULT-CODE-MODEL
; RUN: llc -mtriple thumbv7-windows -mcpu cortex-a9 -code-model large -o - %s \
; RUN: | FileCheck %s -check-prefix CHECK-LARGE-CODE-MODEL
declare dllimport arm_aapcs_vfpcc void @initialise(i8*)
define dllexport arm_aapcs_vfpcc signext i8 @function(i32 %offset) #0 {
entry:
%buffer = alloca [4096 x i8], align 1
%0 = getelementptr inbounds [4096 x i8]* %buffer, i32 0, i32 0
call arm_aapcs_vfpcc void @initialise(i8* %0)
%arrayidx = getelementptr inbounds [4096 x i8]* %buffer, i32 0, i32 %offset
%1 = load i8* %arrayidx, align 1
ret i8 %1
}
attributes #0 = { "stack-probe-size"="8096" }
; CHECK-DEFAULT-CODE-MODEL-NOT: __chkstk
; CHECK-DEFAULT-CODE-MODEL: sub.w sp, sp, #4096
; CHECK-LARGE-CODE-MODEL-NOT: movw r12, :lower16:__chkstk
; CHECK-LARGE-CODE-MODEL-NOT: movt r12, :upper16:__chkstk
; CHECK-LARGE-CODE-MODEL: sub.w sp, sp, #4096