[llvm] r250583 - [WinEH] Fix stack alignment in funclets and ParentFrameOffset calculation
Reid Kleckner via llvm-commits
llvm-commits at lists.llvm.org
Fri Oct 16 16:43:27 PDT 2015
Author: rnk
Date: Fri Oct 16 18:43:27 2015
New Revision: 250583
URL: http://llvm.org/viewvc/llvm-project?rev=250583&view=rev
Log:
[WinEH] Fix stack alignment in funclets and ParentFrameOffset calculation
Our previous value of "16 + 8 + MaxCallFrameSize" for ParentFrameOffset
is incorrect when CSRs are involved. We were supposed to have a test
case to catch this, but it wasn't very rigorous.
The main effect here is that calling _CxxThrowException inside a
catchpad doesn't immediately crash on MOVAPS when you have an odd number
of CSRs.
Modified:
llvm/trunk/include/llvm/Target/TargetFrameLowering.h
llvm/trunk/lib/CodeGen/AsmPrinter/WinException.cpp
llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
llvm/trunk/lib/Target/X86/X86FrameLowering.h
llvm/trunk/test/CodeGen/X86/win-catchpad-csrs.ll
Modified: llvm/trunk/include/llvm/Target/TargetFrameLowering.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetFrameLowering.h?rev=250583&r1=250582&r2=250583&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetFrameLowering.h (original)
+++ llvm/trunk/include/llvm/Target/TargetFrameLowering.h Fri Oct 16 18:43:27 2015
@@ -265,6 +265,10 @@ public:
RegScavenger *RS = nullptr) const {
}
+ virtual unsigned getWinEHParentFrameOffset(const MachineFunction &MF) const {
+ report_fatal_error("WinEH not implemented for this target");
+ }
+
/// eliminateCallFramePseudoInstr - This method is called during prolog/epilog
/// code insertion to eliminate call frame setup and destroy pseudo
/// instructions (but only if the Target is using them). It is responsible
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/WinException.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/WinException.cpp?rev=250583&r1=250582&r2=250583&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/WinException.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/WinException.cpp Fri Oct 16 18:43:27 2015
@@ -710,6 +710,13 @@ void WinException::emitCXXFrameHandler3T
OS.EmitValue(create32bitRef(HandlerMapXData), 4); // HandlerArray
}
+ // All funclets use the same parent frame offset currently.
+ unsigned ParentFrameOffset = 0;
+ if (shouldEmitPersonality) {
+ const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
+ ParentFrameOffset = TFI->getWinEHParentFrameOffset(*MF);
+ }
+
for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
MCSymbol *HandlerMapXData = HandlerMaps[I];
@@ -749,13 +756,8 @@ void WinException::emitCXXFrameHandler3T
OS.EmitValue(create32bitRef(HT.TypeDescriptor), 4); // Type
OS.EmitValue(FrameAllocOffsetRef, 4); // CatchObjOffset
OS.EmitValue(create32bitRef(HandlerSym), 4); // Handler
-
- if (shouldEmitPersonality) {
- // Keep this in sync with X86FrameLowering::emitPrologue.
- int ParentFrameOffset =
- 16 + 8 + MF->getFrameInfo()->getMaxCallFrameSize();
+ if (shouldEmitPersonality)
OS.EmitIntValue(ParentFrameOffset, 4); // ParentFrameOffset
- }
}
}
}
Modified: llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FrameLowering.cpp?rev=250583&r1=250582&r2=250583&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FrameLowering.cpp Fri Oct 16 18:43:27 2015
@@ -786,7 +786,7 @@ void X86FrameLowering::emitPrologue(Mach
// NumBytes value that we would've used for the parent frame.
unsigned ParentFrameNumBytes = NumBytes;
if (IsFunclet)
- NumBytes = MFI->getMaxCallFrameSize();
+ NumBytes = getWinEHFuncletFrameSize(MF);
// Skip the callee-saved push instructions.
bool PushedRegs = false;
@@ -1039,6 +1039,22 @@ static bool isFuncletReturnInstr(Machine
llvm_unreachable("impossible");
}
+unsigned X86FrameLowering::getWinEHFuncletFrameSize(const MachineFunction &MF) const {
+ // This is the size of the pushed CSRs.
+ unsigned CSSize =
+ MF.getInfo<X86MachineFunctionInfo>()->getCalleeSavedFrameSize();
+ // This is the amount of stack a funclet needs to allocate.
+ unsigned MaxCallSize = MF.getFrameInfo()->getMaxCallFrameSize();
+ // RBP is not included in the callee saved register block. After pushing RBP,
+ // everything is 16 byte aligned. Everything we allocate before an outgoing
+ // call must also be 16 byte aligned.
+ unsigned FrameSizeMinusRBP =
+ RoundUpToAlignment(CSSize + MaxCallSize, getStackAlignment());
+ // Subtract out the size of the callee saved registers. This is how much stack
+ // each funclet will allocate.
+ return FrameSizeMinusRBP - CSSize;
+}
+
void X86FrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
@@ -1067,7 +1083,7 @@ void X86FrameLowering::emitEpilogue(Mach
uint64_t NumBytes = 0;
if (MBBI->getOpcode() == X86::CATCHRET) {
- NumBytes = MFI->getMaxCallFrameSize();
+ NumBytes = getWinEHFuncletFrameSize(MF);
assert(hasFP(MF) && "EH funclets without FP not yet implemented");
MachineBasicBlock *TargetMBB = MBBI->getOperand(0).getMBB();
@@ -1107,7 +1123,7 @@ void X86FrameLowering::emitEpilogue(Mach
.addMBB(TargetMBB);
}
} else if (MBBI->getOpcode() == X86::CLEANUPRET) {
- NumBytes = MFI->getMaxCallFrameSize();
+ NumBytes = getWinEHFuncletFrameSize(MF);
assert(hasFP(MF) && "EH funclets without FP not yet implemented");
BuildMI(MBB, MBBI, DL, TII.get(Is64Bit ? X86::POP64r : X86::POP32r),
MachineFramePtr)
@@ -2211,3 +2227,15 @@ MachineBasicBlock::iterator X86FrameLowe
}
return MBBI;
}
+
+unsigned X86FrameLowering::getWinEHParentFrameOffset(const MachineFunction &MF) const {
+ // RDX, the parent frame pointer, is homed into 16(%rsp) in the prologue.
+ unsigned Offset = 16;
+ // RBP is immediately pushed.
+ Offset += SlotSize;
+ // All callee-saved registers are then pushed.
+ Offset += MF.getInfo<X86MachineFunctionInfo>()->getCalleeSavedFrameSize();
+ // Every funclet allocates enough stack space for the largest outgoing call.
+ Offset += getWinEHFuncletFrameSize(MF);
+ return Offset;
+}
Modified: llvm/trunk/lib/Target/X86/X86FrameLowering.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FrameLowering.h?rev=250583&r1=250582&r2=250583&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FrameLowering.h (original)
+++ llvm/trunk/lib/Target/X86/X86FrameLowering.h Fri Oct 16 18:43:27 2015
@@ -101,6 +101,8 @@ public:
MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const override;
+ unsigned getWinEHParentFrameOffset(const MachineFunction &MF) const override;
+
/// Check the instruction before/after the passed instruction. If
/// it is an ADD/SUB/LEA instruction it is deleted argument and the
/// stack adjustment is returned as a positive value for ADD/LEA and
@@ -152,6 +154,8 @@ private:
restoreWin32EHStackPointers(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI, DebugLoc DL,
bool RestoreSP = false) const;
+
+ unsigned getWinEHFuncletFrameSize(const MachineFunction &MF) const;
};
} // End llvm namespace
Modified: llvm/trunk/test/CodeGen/X86/win-catchpad-csrs.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/win-catchpad-csrs.ll?rev=250583&r1=250582&r2=250583&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/win-catchpad-csrs.ll (original)
+++ llvm/trunk/test/CodeGen/X86/win-catchpad-csrs.ll Fri Oct 16 18:43:27 2015
@@ -125,14 +125,20 @@ catchendblock:
; X64: .seh_pushreg 5
; X64: pushq %rsi
; X64: .seh_pushreg 6
-; X64: subq $32, %rsp
-; X64: .seh_stackalloc 32
+; X64: pushq %rdi
+; X64: .seh_pushreg 7
+; X64: pushq %rbx
+; X64: .seh_pushreg 3
+; X64: subq $40, %rsp
+; X64: .seh_stackalloc 40
; X64: leaq 32(%rdx), %rbp
; X64: .seh_endprologue
; X64: movl $2, %ecx
; X64: callq f
; X64: leaq [[contbb]](%rip), %rax
-; X64: addq $32, %rsp
+; X64: addq $40, %rsp
+; X64: popq %rbx
+; X64: popq %rdi
; X64: popq %rsi
; X64: popq %rbp
; X64: retq
@@ -142,4 +148,130 @@ catchendblock:
; X64: .long "??_R0H at 8"@IMGREL
; X64: .long 0
; X64: .long "?catch$[[catch1bb]]@?0?try_catch_catch at 4HA"@IMGREL
+; X64: .long 88
+
+define i32 @try_one_csr() personality i32 (...)* @__CxxFrameHandler3 {
+entry:
+ %a = call i32 @getint()
+ %b = call i32 @getint()
+ call void (...) @useints(i32 %a)
+ invoke void @f(i32 1)
+ to label %try.cont unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %entry
+ %0 = catchpad [%rtti.TypeDescriptor2* @"\01??_R0H at 8", i32 0, i8* null]
+ to label %catch unwind label %catchendblock
+
+catch:
+ catchret %0 to label %try.cont
+
+try.cont: ; preds = %entry, %invoke.cont.2, %invoke.cont.3
+ ret i32 0
+
+catchendblock: ; preds = %catch,
+ catchendpad unwind to caller
+}
+
+; X64-LABEL: try_one_csr:
+; X64: pushq %rbp
+; X64: .seh_pushreg 5
+; X64: pushq %rsi
+; X64: .seh_pushreg 6
+; X64-NOT: pushq
+; X64: subq $40, %rsp
+; X64: .seh_stackalloc 40
+; X64: leaq 32(%rsp), %rbp
+; X64: .seh_setframe 5, 32
+; X64: .seh_endprologue
+; X64: callq getint
+; X64: callq getint
+; X64: callq useints
+; X64: movl $1, %ecx
+; X64: callq f
+; X64: [[contbb:\.LBB1_[0-9]+]]: # %try.cont
+; X64: addq $40, %rsp
+; X64-NOT: popq
+; X64: popq %rsi
+; X64: popq %rbp
+; X64: retq
+
+; X64: "?catch$[[catch1bb:[0-9]+]]@?0?try_one_csr at 4HA":
+; X64: LBB1_[[catch1bb]]: # %catch.dispatch{{$}}
+; X64: movq %rdx, 16(%rsp)
+; X64: pushq %rbp
+; X64: .seh_pushreg 5
+; X64: pushq %rsi
+; X64: .seh_pushreg 6
+; X64: subq $40, %rsp
+; X64: .seh_stackalloc 40
+; X64: leaq 32(%rdx), %rbp
+; X64: .seh_endprologue
+; X64: leaq [[contbb]](%rip), %rax
+; X64: addq $40, %rsp
+; X64: popq %rsi
+; X64: popq %rbp
+; X64: retq
+
+; X64: $handlerMap$0$try_one_csr:
+; X64: .long 0
+; X64: .long "??_R0H at 8"@IMGREL
+; X64: .long 0
+; X64: .long "?catch$[[catch1bb]]@?0?try_one_csr at 4HA"@IMGREL
+; X64: .long 72
+
+define i32 @try_no_csr() personality i32 (...)* @__CxxFrameHandler3 {
+entry:
+ invoke void @f(i32 1)
+ to label %try.cont unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %entry
+ %0 = catchpad [%rtti.TypeDescriptor2* @"\01??_R0H at 8", i32 0, i8* null]
+ to label %catch unwind label %catchendblock
+
+catch:
+ catchret %0 to label %try.cont
+
+try.cont: ; preds = %entry, %invoke.cont.2, %invoke.cont.3
+ ret i32 0
+
+catchendblock: ; preds = %catch,
+ catchendpad unwind to caller
+}
+
+; X64-LABEL: try_no_csr:
+; X64: pushq %rbp
+; X64: .seh_pushreg 5
+; X64-NOT: pushq
+; X64: subq $48, %rsp
+; X64: .seh_stackalloc 48
+; X64: leaq 48(%rsp), %rbp
+; X64: .seh_setframe 5, 48
+; X64: .seh_endprologue
+; X64: movl $1, %ecx
+; X64: callq f
+; X64: [[contbb:\.LBB2_[0-9]+]]: # %try.cont
+; X64: addq $48, %rsp
+; X64-NOT: popq
+; X64: popq %rbp
+; X64: retq
+
+; X64: "?catch$[[catch1bb:[0-9]+]]@?0?try_no_csr at 4HA":
+; X64: LBB2_[[catch1bb]]: # %catch.dispatch{{$}}
+; X64: movq %rdx, 16(%rsp)
+; X64: pushq %rbp
+; X64: .seh_pushreg 5
+; X64: subq $32, %rsp
+; X64: .seh_stackalloc 32
+; X64: leaq 48(%rdx), %rbp
+; X64: .seh_endprologue
+; X64: leaq [[contbb]](%rip), %rax
+; X64: addq $32, %rsp
+; X64: popq %rbp
+; X64: retq
+
+; X64: $handlerMap$0$try_no_csr:
+; X64: .long 0
+; X64: .long "??_R0H at 8"@IMGREL
+; X64: .long 0
+; X64: .long "?catch$[[catch1bb]]@?0?try_no_csr at 4HA"@IMGREL
; X64: .long 56
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