Fixes the last x86-64 test failure in compat.exp:

<16 x float> is 64-byte aligned (for some reason),
which gets us into the stack realignment code.  The
computation changing FP-relative offsets to SP-relative
was broken, assiging a spill temp to a location
also used for parameter passing.  This
fixes it by rounding up the stack frame to a multiple
of the largest alignment (I concluded it wasn't fixable
without doing this, but I'm not very sure.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52750 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dale Johannesen 2008-06-26 01:51:13 +00:00
parent 872a738775
commit b5dae00325
4 changed files with 18 additions and 7 deletions

View File

@ -516,6 +516,13 @@ public:
return !hasFP(MF);
}
// needsStackRealignment - true if storage within the function requires the
// stack pointer to be aligned more than the normal calling convention calls
// for.
virtual bool needsStackRealignment(const MachineFunction &MF) const {
return false;
}
/// getCallFrameSetup/DestroyOpcode - These methods return the opcode of the
/// frame setup/destroy instructions if they exist (-1 otherwise). Some
/// targets use pseudo instructions in order to abstract away the difference

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@ -459,15 +459,19 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
// Round up the size to a multiple of the alignment, but only if there are
// calls or alloca's in the function. This ensures that any calls to
// subroutines have their stack frames suitable aligned.
// Also do this if we need runtime alignment of the stack. In this case
// offsets will be relative to SP not FP; round up the stack size so this
// works.
if (!RegInfo->targetHandlesStackFrameRounding() &&
(FFI->hasCalls() || FFI->hasVarSizedObjects())) {
(FFI->hasCalls() || FFI->hasVarSizedObjects() ||
RegInfo->needsStackRealignment(Fn))) {
// If we have reserved argument space for call sites in the function
// immediately on entry to the current function, count it as part of the
// overall stack size.
if (RegInfo->hasReservedCallFrame(Fn))
Offset += FFI->getMaxCallFrameSize();
unsigned AlignMask = TFI.getStackAlignment() - 1;
unsigned AlignMask = std::max(TFI.getStackAlignment(),MaxAlign) - 1;
Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
}

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@ -302,11 +302,9 @@ X86RegisterInfo::getFrameIndexOffset(MachineFunction &MF, int FI) const {
// Skip the saved EBP
Offset += SlotSize;
else {
unsigned MaxAlign = MF.getFrameInfo()->getMaxAlignment();
uint64_t FrameSize =
(StackSize - SlotSize + MaxAlign - 1)/MaxAlign*MaxAlign;
return Offset + FrameSize - SlotSize;
unsigned Align = MF.getFrameInfo()->getObjectAlignment(FI);
assert( (-(Offset + StackSize)) % Align == 0);
return Offset + StackSize;
}
// FIXME: Support tail calls

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@ -64,6 +64,8 @@ void RegisterInfoEmitter::runHeader(std::ostream &OS) {
<< " virtual int getDwarfRegNumFull(unsigned RegNum, "
<< "unsigned Flavour) const;\n"
<< " virtual int getDwarfRegNum(unsigned RegNum, bool isEH) const = 0;\n"
<< " virtual bool needsStackRealignment(const MachineFunction &) const\n"
<< " { return false; }\n"
<< " unsigned getSubReg(unsigned RegNo, unsigned Index) const;\n"
<< "};\n\n";