[ARM] Fix Scavenger assert due to underestimated stack size
Summary:
Currently, when checking if a stack is "BigStack" or not, it doesn't count into spills and arguments. Therefore, LLVM won't reserve spill slot for this actually "BigStack". This may cause scavenger failure.
Reviewers: rengolin
Subscribers: aemerson, rengolin, tberghammer, danalbert, srhines, llvm-commits
Differential Revision: http://reviews.llvm.org/D19896
llvm-svn: 268529
diff --git a/llvm/lib/Target/ARM/ARMFrameLowering.cpp b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
index 808a21f..cc026d8 100644
--- a/llvm/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
@@ -1479,6 +1479,7 @@
bool CS1Spilled = false;
bool LRSpilled = false;
unsigned NumGPRSpills = 0;
+ unsigned NumFPRSpills = 0;
SmallVector<unsigned, 4> UnspilledCS1GPRs;
SmallVector<unsigned, 4> UnspilledCS2GPRs;
const ARMBaseRegisterInfo *RegInfo = static_cast<const ARMBaseRegisterInfo *>(
@@ -1533,8 +1534,17 @@
CanEliminateFrame = false;
}
- if (!ARM::GPRRegClass.contains(Reg))
+ if (!ARM::GPRRegClass.contains(Reg)) {
+ if (Spilled) {
+ if (ARM::SPRRegClass.contains(Reg))
+ NumFPRSpills++;
+ else if (ARM::DPRRegClass.contains(Reg))
+ NumFPRSpills += 2;
+ else if (ARM::QPRRegClass.contains(Reg))
+ NumFPRSpills += 4;
+ }
continue;
+ }
if (Spilled) {
NumGPRSpills++;
@@ -1607,11 +1617,14 @@
// FIXME: We could add logic to be more precise about negative offsets
// and which instructions will need a scratch register for them. Is it
// worth the effort and added fragility?
- bool BigStack = (RS && (MFI->estimateStackSize(MF) +
- ((hasFP(MF) && AFI->hasStackFrame()) ? 4 : 0) >=
- estimateRSStackSizeLimit(MF, this))) ||
- MFI->hasVarSizedObjects() ||
- (MFI->adjustsStack() && !canSimplifyCallFramePseudos(MF));
+ auto ArgStackSize = MF.getInfo<ARMFunctionInfo>()->getArgumentStackSize();
+ bool BigStack =
+ (RS && (MFI->estimateStackSize(MF) + 4 * (NumGPRSpills + NumFPRSpills) +
+ (!hasFP(MF) ? ArgStackSize : 0) + 16 /* possible paddings */ +
+ ((hasFP(MF) && AFI->hasStackFrame()) ? 4 : 0) >=
+ estimateRSStackSizeLimit(MF, this))) ||
+ MFI->hasVarSizedObjects() ||
+ (MFI->adjustsStack() && !canSimplifyCallFramePseudos(MF));
bool ExtraCSSpill = false;
if (BigStack || !CanEliminateFrame || RegInfo->cannotEliminateFrame(MF)) {