[llvm] r230113 - Win64: Stack alignment constraints aren't applied during SET_FPREG
David Majnemer
david.majnemer at gmail.com
Fri Feb 20 17:04:48 PST 2015
Author: majnemer
Date: Fri Feb 20 19:04:47 2015
New Revision: 230113
URL: http://llvm.org/viewvc/llvm-project?rev=230113&view=rev
Log:
Win64: Stack alignment constraints aren't applied during SET_FPREG
Stack realignment occurs after the prolog, not during, for Win64.
Because of this, don't factor in the maximum stack alignment when
establishing a frame pointer.
This fixes PR22572.
Modified:
llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
llvm/trunk/test/CodeGen/X86/win64_eh.ll
llvm/trunk/test/CodeGen/X86/win64_frame.ll
Modified: llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FrameLowering.cpp?rev=230113&r1=230112&r2=230113&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FrameLowering.cpp Fri Feb 20 19:04:47 2015
@@ -458,7 +458,7 @@ static unsigned calculateSetFPREG(uint64
const uint64_t Win64MaxSEHOffset = 128;
uint64_t SEHFrameOffset = std::min(SPAdjust, Win64MaxSEHOffset);
// Win64 ABI requires 16-byte alignment for the UWOP_SET_FPREG opcode.
- return static_cast<unsigned>(RoundUpToAlignment(SEHFrameOffset, 16));
+ return SEHFrameOffset & -16;
}
// If we're forcing a stack realignment we can't rely on just the frame
@@ -672,14 +672,12 @@ void X86FrameLowering::emitPrologue(Mach
// If required, include space for extra hidden slot for stashing base pointer.
if (X86FI->getRestoreBasePointer())
FrameSize += SlotSize;
- if (RegInfo->needsStackRealignment(MF)) {
- // Callee-saved registers are pushed on stack before the stack
- // is realigned.
- FrameSize -= X86FI->getCalleeSavedFrameSize();
- NumBytes = RoundUpToAlignment(FrameSize, MaxAlign);
- } else {
- NumBytes = FrameSize - X86FI->getCalleeSavedFrameSize();
- }
+
+ NumBytes = FrameSize - X86FI->getCalleeSavedFrameSize();
+
+ // Callee-saved registers are pushed on stack before the stack is realigned.
+ if (RegInfo->needsStackRealignment(MF) && !IsWinEH)
+ NumBytes = RoundUpToAlignment(NumBytes, MaxAlign);
// Get the offset of the stack slot for the EBP register, which is
// guaranteed to be the last slot by processFunctionBeforeFrameFinalized.
@@ -801,7 +799,10 @@ void X86FrameLowering::emitPrologue(Mach
// responsible for adjusting the stack pointer. Touching the stack at 4K
// increments is necessary to ensure that the guard pages used by the OS
// virtual memory manager are allocated in correct sequence.
- if (NumBytes >= StackProbeSize && UseStackProbe) {
+ uint64_t AlignedNumBytes = NumBytes;
+ if (IsWinEH && RegInfo->needsStackRealignment(MF))
+ AlignedNumBytes = RoundUpToAlignment(AlignedNumBytes, MaxAlign);
+ if (AlignedNumBytes >= StackProbeSize && UseStackProbe) {
// Check whether EAX is livein for this function.
bool isEAXAlive = isEAXLiveIn(MF);
@@ -1005,14 +1006,12 @@ void X86FrameLowering::emitEpilogue(Mach
if (hasFP(MF)) {
// Calculate required stack adjustment.
uint64_t FrameSize = StackSize - SlotSize;
- if (RegInfo->needsStackRealignment(MF)) {
- // Callee-saved registers were pushed on stack before the stack
- // was realigned.
- FrameSize -= CSSize;
- NumBytes = (FrameSize + MaxAlign - 1) / MaxAlign * MaxAlign;
- } else {
- NumBytes = FrameSize - CSSize;
- }
+ NumBytes = FrameSize - CSSize;
+
+ // Callee-saved registers were pushed on stack before the stack was
+ // realigned.
+ if (RegInfo->needsStackRealignment(MF) && !IsWinEH)
+ NumBytes = RoundUpToAlignment(FrameSize, MaxAlign);
// Pop EBP.
BuildMI(MBB, MBBI, DL,
@@ -1185,25 +1184,15 @@ int X86FrameLowering::getFrameIndexOffse
int64_t FPDelta = 0;
if (IsWinEH) {
- uint64_t NumBytes = 0;
+ assert(!MFI->hasCalls() || (StackSize % 16) == 8);
+
// Calculate required stack adjustment.
uint64_t FrameSize = StackSize - SlotSize;
// If required, include space for extra hidden slot for stashing base pointer.
if (X86FI->getRestoreBasePointer())
FrameSize += SlotSize;
- uint64_t SEHStackAllocAmt = StackSize;
- if (RegInfo->needsStackRealignment(MF)) {
- // Callee-saved registers are pushed on stack before the stack
- // is realigned.
- FrameSize -= CSSize;
+ uint64_t NumBytes = FrameSize - CSSize;
- uint64_t MaxAlign =
- calculateMaxStackAlign(MF); // Desired stack alignment.
- NumBytes = RoundUpToAlignment(FrameSize, MaxAlign);
- SEHStackAllocAmt = RoundUpToAlignment(SEHStackAllocAmt, 16);
- } else {
- NumBytes = FrameSize - CSSize;
- }
uint64_t SEHFrameOffset = calculateSetFPREG(NumBytes);
if (FI && FI == X86FI->getFAIndex())
return -SEHFrameOffset;
@@ -1212,7 +1201,9 @@ int X86FrameLowering::getFrameIndexOffse
// pointer followed by return address and the location required by the
// restricted Win64 prologue.
// Add FPDelta to all offsets below that go through the frame pointer.
- FPDelta = SEHStackAllocAmt - SEHFrameOffset;
+ FPDelta = FrameSize - SEHFrameOffset;
+ assert((!MFI->hasCalls() || (FPDelta % 16) == 0) &&
+ "FPDelta isn't aligned per the Win64 ABI!");
}
@@ -1237,8 +1228,6 @@ int X86FrameLowering::getFrameIndexOffse
} else {
if (!HasFP)
return Offset + StackSize;
- if (IsWinEH)
- return Offset + FPDelta;
// Skip the saved EBP.
Offset += SlotSize;
@@ -1249,7 +1238,7 @@ int X86FrameLowering::getFrameIndexOffse
Offset -= TailCallReturnAddrDelta;
}
- return Offset;
+ return Offset + FPDelta;
}
int X86FrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,
Modified: llvm/trunk/test/CodeGen/X86/win64_eh.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/win64_eh.ll?rev=230113&r1=230112&r2=230113&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/win64_eh.ll (original)
+++ llvm/trunk/test/CodeGen/X86/win64_eh.ll Fri Feb 20 19:04:47 2015
@@ -150,18 +150,18 @@ entry:
; WIN64: .seh_pushreg 7
; WIN64: pushq %rbx
; WIN64: .seh_pushreg 3
-; WIN64: subq $128, %rsp
-; WIN64: .seh_stackalloc 128
-; WIN64: leaq 128(%rsp), %rbp
-; WIN64: .seh_setframe 5, 128
-; WIN64: movaps %xmm7, -32(%rbp) # 16-byte Spill
-; WIN64: .seh_savexmm 7, 96
-; WIN64: movaps %xmm6, -48(%rbp) # 16-byte Spill
-; WIN64: .seh_savexmm 6, 80
+; WIN64: subq $96, %rsp
+; WIN64: .seh_stackalloc 96
+; WIN64: leaq 96(%rsp), %rbp
+; WIN64: .seh_setframe 5, 96
+; WIN64: movaps %xmm7, -16(%rbp) # 16-byte Spill
+; WIN64: .seh_savexmm 7, 80
+; WIN64: movaps %xmm6, -32(%rbp) # 16-byte Spill
+; WIN64: .seh_savexmm 6, 64
; WIN64: .seh_endprologue
; WIN64: andq $-64, %rsp
-; WIN64: movaps -48(%rbp), %xmm6 # 16-byte Reload
-; WIN64: movaps -32(%rbp), %xmm7 # 16-byte Reload
+; WIN64: movaps -32(%rbp), %xmm6 # 16-byte Reload
+; WIN64: movaps -16(%rbp), %xmm7 # 16-byte Reload
; WIN64: leaq (%rbp), %rsp
; WIN64: popq %rbx
; WIN64: popq %rdi
Modified: llvm/trunk/test/CodeGen/X86/win64_frame.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/win64_frame.ll?rev=230113&r1=230112&r2=230113&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/win64_frame.ll (original)
+++ llvm/trunk/test/CodeGen/X86/win64_frame.ll Fri Feb 20 19:04:47 2015
@@ -9,10 +9,10 @@ define i32 @f1(i32 %p1, i32 %p2, i32 %p3
define void @f2(i32 %p, ...) "no-frame-pointer-elim"="true" {
; CHECK-LABEL: f2:
; CHECK: .seh_stackalloc 8
- ; CHECK: leaq 16(%rsp), %rbp
- ; CHECK: .seh_setframe 5, 16
- ; CHECK: movq %rdx, 16(%rbp)
- ; CHECK: leaq 16(%rbp), %rax
+ ; CHECK: leaq (%rsp), %rbp
+ ; CHECK: .seh_setframe 5, 0
+ ; CHECK: movq %rdx, 32(%rbp)
+ ; CHECK: leaq 32(%rbp), %rax
%ap = alloca i8, align 8
call void @llvm.va_start(i8* %ap)
ret void
@@ -76,20 +76,21 @@ define i32 @f7(i32 %a, i32 %b, i32 %c, i
; CHECK-LABEL: f7:
; CHECK: pushq %rbp
; CHECK: .seh_pushreg 5
- ; CHECK: subq $320, %rsp
- ; CHECK: .seh_stackalloc 320
+ ; CHECK: subq $304, %rsp
+ ; CHECK: .seh_stackalloc 304
; CHECK: leaq 128(%rsp), %rbp
; CHECK: .seh_setframe 5, 128
- ; CHECK: movl 240(%rbp), %eax
- ; CHECK: leaq 192(%rbp), %rsp
+ ; CHECK: andq $-64, %rsp
+ ; CHECK: movl 224(%rbp), %eax
+ ; CHECK: leaq 176(%rbp), %rsp
alloca [300 x i8], align 64
ret i32 %e
}
define i32 @f8(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) "no-frame-pointer-elim"="true" {
; CHECK-LABEL: f8:
- ; CHECK: subq $384, %rsp
- ; CHECK: .seh_stackalloc 384
+ ; CHECK: subq $352, %rsp
+ ; CHECK: .seh_stackalloc 352
; CHECK: leaq 128(%rsp), %rbp
; CHECK: .seh_setframe 5, 128
@@ -113,7 +114,7 @@ define i32 @f8(i32 %a, i32 %b, i32 %c, i
ret i32 %e
; CHECK: movl %esi, %eax
- ; CHECK: leaq 256(%rbp), %rsp
+ ; CHECK: leaq 224(%rbp), %rsp
}
declare i8* @llvm.returnaddress(i32) nounwind readnone
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