Revert "Fix miscompile of MS inline assembly with stack realignment"

This reverts commit r196876.  Its tests failed on the bots, so I'll
figure it out tomorrow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196879 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Kleckner 2013-12-10 05:31:27 +00:00
parent ec4d326aad
commit cc8d39acf5
10 changed files with 35 additions and 108 deletions

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@ -223,10 +223,6 @@ class MachineFrameInfo {
/// Whether the "realign-stack" option is on.
bool RealignOption;
/// True if the function includes inline assembly that adjusts the stack
/// pointer.
bool HasInlineAsmWithSPAdjust;
const TargetFrameLowering *getFrameLowering() const;
public:
explicit MachineFrameInfo(const TargetMachine &TM, bool RealignOpt)
@ -455,10 +451,6 @@ public:
bool hasCalls() const { return HasCalls; }
void setHasCalls(bool V) { HasCalls = V; }
/// Returns true if the function contains any stack-adjusting inline assembly.
bool hasInlineAsmWithSPAdjust() const { return HasInlineAsmWithSPAdjust; }
void setHasInlineAsmWithSPAdjust(bool B) { HasInlineAsmWithSPAdjust = B; }
/// getMaxCallFrameSize - Return the maximum size of a call frame that must be
/// allocated for an outgoing function call. This is only available if
/// CallFrameSetup/Destroy pseudo instructions are used by the target, and

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@ -131,8 +131,8 @@ class MachineFunction {
/// about the control flow of such functions.
bool ExposesReturnsTwice;
/// True if the function includes any inline assembly.
bool HasInlineAsm;
/// True if the function includes MS-style inline assembly.
bool HasMSInlineAsm;
MachineFunction(const MachineFunction &) LLVM_DELETED_FUNCTION;
void operator=(const MachineFunction&) LLVM_DELETED_FUNCTION;
@ -218,14 +218,15 @@ public:
ExposesReturnsTwice = B;
}
/// Returns true if the function contains any inline assembly.
bool hasInlineAsm() const {
return HasInlineAsm;
/// Returns true if the function contains any MS-style inline assembly.
bool hasMSInlineAsm() const {
return HasMSInlineAsm;
}
/// Set a flag that indicates that the function contains inline assembly.
void setHasInlineAsm(bool B) {
HasInlineAsm = B;
/// Set a flag that indicates that the function contains MS-style inline
/// assembly.
void setHasMSInlineAsm(bool B) {
HasMSInlineAsm = B;
}
/// getInfo - Keep track of various per-function pieces of information for

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@ -851,20 +851,12 @@ void RegsForValue::AddInlineAsmOperands(unsigned Code, bool HasMatching,
SDValue Res = DAG.getTargetConstant(Flag, MVT::i32);
Ops.push_back(Res);
unsigned SP = TLI.getStackPointerRegisterToSaveRestore();
for (unsigned Value = 0, Reg = 0, e = ValueVTs.size(); Value != e; ++Value) {
unsigned NumRegs = TLI.getNumRegisters(*DAG.getContext(), ValueVTs[Value]);
MVT RegisterVT = RegVTs[Value];
for (unsigned i = 0; i != NumRegs; ++i) {
assert(Reg < Regs.size() && "Mismatch in # registers expected");
unsigned TheReg = Regs[Reg++];
Ops.push_back(DAG.getRegister(TheReg, RegisterVT));
// Notice if we clobbered the stack pointer. Yes, inline asm can do this.
if (TheReg == SP && Code == InlineAsm::Kind_Clobber) {
MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
MFI->setHasInlineAsmWithSPAdjust(true);
}
Ops.push_back(DAG.getRegister(Regs[Reg++], RegisterVT));
}
}
}

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@ -428,9 +428,7 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
SDB->init(GFI, *AA, LibInfo);
MF->setHasInlineAsm(false);
MF->getFrameInfo()->setHasInlineAsmWithSPAdjust(false);
MF->setHasMSInlineAsm(false);
SelectAllBasicBlocks(Fn);
// If the first basic block in the function has live ins that need to be
@ -514,7 +512,7 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E;
++I) {
if (MFI->hasCalls() && MF->hasInlineAsm())
if (MFI->hasCalls() && MF->hasMSInlineAsm())
break;
const MachineBasicBlock *MBB = I;
@ -525,8 +523,8 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
II->isStackAligningInlineAsm()) {
MFI->setHasCalls(true);
}
if (II->isInlineAsm()) {
MF->setHasInlineAsm(true);
if (II->isMSInlineAsm()) {
MF->setHasMSInlineAsm(true);
}
}
}

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@ -4208,11 +4208,6 @@ bool AsmParser::parseMSInlineAsm(
AsmStrRewrites.push_back(AsmRewrite(AOK_Input, Start, SymName.size()));
}
}
// Consider implicit defs to be clobbers. Think of cpuid and push.
const uint16_t *ImpDefs = Desc.getImplicitDefs();
for (unsigned I = 0, E = Desc.getNumImplicitDefs(); I != E; ++I)
ClobberRegs.push_back(ImpDefs[I]);
}
// Set the number of Outputs and Inputs.

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@ -50,7 +50,7 @@ bool X86FrameLowering::hasFP(const MachineFunction &MF) const {
return (MF.getTarget().Options.DisableFramePointerElim(MF) ||
RegInfo->needsStackRealignment(MF) ||
MFI->hasVarSizedObjects() ||
MFI->isFrameAddressTaken() || MFI->hasInlineAsmWithSPAdjust() ||
MFI->isFrameAddressTaken() || MF.hasMSInlineAsm() ||
MF.getInfo<X86MachineFunctionInfo>()->getForceFramePointer() ||
MMI.callsUnwindInit() || MMI.callsEHReturn());
}

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@ -347,12 +347,6 @@ BitVector X86RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
"Stack realignment in presence of dynamic allocas is not supported with"
"this calling convention.");
// FIXME: Do a proper analysis of the inline asm to see if it actually
// conflicts with the base register we chose.
if (MF.hasInlineAsm())
report_fatal_error("Stack realignment in presence of dynamic stack "
"adjustments is not supported with inline assembly.");
for (MCSubRegIterator I(getBaseRegister(), this, /*IncludeSelf=*/true);
I.isValid(); ++I)
Reserved.set(*I);
@ -409,15 +403,18 @@ bool X86RegisterInfo::hasBasePointer(const MachineFunction &MF) const {
if (!EnableBasePointer)
return false;
// When we need stack realignment, we can't address the stack from the frame
// pointer. When we have dynamic allocas or stack-adjusting inline asm, we
// can't address variables from the stack pointer. MS inline asm can
// reference locals while also adjusting the stack pointer. When we can't
// use both the SP and the FP, we need a separate base pointer register.
bool CantUseFP = needsStackRealignment(MF);
bool CantUseSP =
MFI->hasVarSizedObjects() || MFI->hasInlineAsmWithSPAdjust();
return CantUseFP && CantUseSP;
// When we need stack realignment and there are dynamic allocas, we can't
// reference off of the stack pointer, so we reserve a base pointer.
//
// This is also true if the function contain MS-style inline assembly. We
// do this because if any stack changes occur in the inline assembly, e.g.,
// "pusha", then any C local variable or C argument references in the
// inline assembly will be wrong because the SP is not properly tracked.
if ((needsStackRealignment(MF) && MFI->hasVarSizedObjects()) ||
MF.hasMSInlineAsm())
return true;
return false;
}
bool X86RegisterInfo::canRealignStack(const MachineFunction &MF) const {

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@ -1,16 +0,0 @@
; RUN: not llc -march x86 < %s 2>&1 | FileCheck %s
; We don't currently support realigning the stack and adjusting the stack
; pointer in inline asm. This commonly happens in MS inline assembly using
; push and pop.
; CHECK: Stack realignment in presence of dynamic stack adjustments is not supported with inline assembly
define i32 @foo() {
entry:
%r = alloca i32, align 16
store i32 -1, i32* %r, align 16
call void asm sideeffect inteldialect "push esi\0A\09xor esi, esi\0A\09mov dword ptr $0, esi\0A\09pop esi", "=*m,~{flags},~{esi},~{esp},~{dirflag},~{fpsr},~{flags}"(i32* %r)
%0 = load i32* %r, align 16
ret i32 %0
}

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@ -1,15 +0,0 @@
; RUN: not llc -march x86 < %s 2>&1 | FileCheck %s
; We don't currently support realigning the stack and adjusting the stack
; pointer in inline asm. This can even happen in GNU asm.
; CHECK: Stack realignment in presence of dynamic stack adjustments is not supported with inline assembly
define i32 @foo() {
entry:
%r = alloca i32, align 16
store i32 -1, i32* %r, align 16
call void asm sideeffect "push %esi\0A\09xor %esi, %esi\0A\09mov %esi, $0\0A\09pop %esi", "=*m,~{flags},~{esi},~{esp},~{dirflag},~{fpsr},~{flags}"(i32* %r)
%0 = load i32* %r, align 16
ret i32 %0
}

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@ -5,6 +5,7 @@ entry:
%0 = tail call i32 asm sideeffect inteldialect "mov eax, $1\0A\09mov $0, eax", "=r,r,~{eax},~{dirflag},~{fpsr},~{flags}"(i32 1) nounwind
ret i32 %0
; CHECK: t1
; CHECK: movl %esp, %ebp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: mov eax, ecx
@ -18,6 +19,7 @@ entry:
call void asm sideeffect inteldialect "mov eax, $$1", "~{eax},~{dirflag},~{fpsr},~{flags}"() nounwind
ret void
; CHECK: t2
; CHECK: movl %esp, %ebp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: mov eax, 1
@ -32,6 +34,7 @@ entry:
call void asm sideeffect inteldialect "mov eax, DWORD PTR [$0]", "*m,~{eax},~{dirflag},~{fpsr},~{flags}"(i32* %V.addr) nounwind
ret void
; CHECK: t3
; CHECK: movl %esp, %ebp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: mov eax, DWORD PTR {{[[esp]}}
@ -53,6 +56,7 @@ entry:
%0 = load i32* %b1, align 4
ret i32 %0
; CHECK: t18
; CHECK: movl %esp, %ebp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: lea ebx, foo
@ -72,6 +76,7 @@ entry:
call void asm sideeffect inteldialect "call $0", "r,~{dirflag},~{fpsr},~{flags}"(void ()* @t19_helper) nounwind
ret void
; CHECK-LABEL: t19:
; CHECK: movl %esp, %ebp
; CHECK: movl ${{_?}}t19_helper, %eax
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
@ -90,6 +95,7 @@ entry:
%0 = load i32** %res, align 4
ret i32* %0
; CHECK-LABEL: t30:
; CHECK: movl %esp, %ebp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: lea edi, dword ptr [{{_?}}results]
@ -97,31 +103,8 @@ entry:
; CHECK: {{## InlineAsm End|#NO_APP}}
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: mov dword ptr [esp], edi
; CHECK: mov dword ptr [esi], edi
; CHECK: .att_syntax
; CHECK: {{## InlineAsm End|#NO_APP}}
; CHECK: movl (%esp), %eax
}
; Stack realignment plus MS inline asm that does *not* adjust the stack is no
; longer an error.
define i32 @t31() {
entry:
%val = alloca i32, align 16
store i32 -1, i32* %val, align 16
call void asm sideeffect inteldialect "mov dword ptr $0, esp", "=*m,~{dirflag},~{fpsr},~{flags}"(i32* %val) #1
%sp = load i32* %val, align 16
ret i32 %sp
; CHECK-LABEL: t31:
; CHECK: pushl %ebp
; CHECK: movl %esp, %ebp
; CHECK: andl $-16, %esp
; CHECK: {{## InlineAsm Start|#APP}}
; CHECK: .intel_syntax
; CHECK: mov dword ptr [esp], esp
; CHECK: .att_syntax
; CHECK: {{## InlineAsm End|#NO_APP}}
; CHECK: movl (%esp), %eax
; CHECK: ret
; CHECK: movl (%esi), %eax
}