[llvm-commits] [llvm] r115479 - in /llvm/trunk: lib/Target/X86/X86Instr64bit.td lib/Target/X86/X86RegisterInfo.cpp test/CodeGen/X86/win_chkstk.ll
Anton Korobeynikov
asl at math.spbu.ru
Sun Oct 3 15:02:38 PDT 2010
Author: asl
Date: Sun Oct 3 17:02:38 2010
New Revision: 115479
URL: http://llvm.org/viewvc/llvm-project?rev=115479&view=rev
Log:
Properly emit stack probe on win64 (for non-mingw targets).
Based on the patch by Cameron Esfahani!
Modified:
llvm/trunk/lib/Target/X86/X86Instr64bit.td
llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp
llvm/trunk/test/CodeGen/X86/win_chkstk.ll
Modified: llvm/trunk/lib/Target/X86/X86Instr64bit.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86Instr64bit.td?rev=115479&r1=115478&r2=115479&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86Instr64bit.td (original)
+++ llvm/trunk/lib/Target/X86/X86Instr64bit.td Sun Oct 3 17:02:38 2010
@@ -171,13 +171,13 @@
Uses = [RSP] in {
def WINCALL64pcrel32 : Ii32PCRel<0xE8, RawFrm,
(outs), (ins i64i32imm_pcrel:$dst, variable_ops),
- "call\t$dst", []>,
+ "call{q}\t$dst", []>,
Requires<[IsWin64]>;
def WINCALL64r : I<0xFF, MRM2r, (outs), (ins GR64:$dst, variable_ops),
- "call\t{*}$dst",
+ "call{q}\t{*}$dst",
[(X86call GR64:$dst)]>, Requires<[IsWin64]>;
- def WINCALL64m : I<0xFF, MRM2m, (outs),
- (ins i64mem:$dst, variable_ops), "call\t{*}$dst",
+ def WINCALL64m : I<0xFF, MRM2m, (outs), (ins i64mem:$dst,variable_ops),
+ "call{q}\t{*}$dst",
[(X86call (loadi64 addr:$dst))]>,
Requires<[IsWin64]>;
}
Modified: llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp?rev=115479&r1=115478&r2=115479&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp Sun Oct 3 17:02:38 2010
@@ -871,6 +871,19 @@
}
}
+static bool isEAXLiveIn(MachineFunction &MF) {
+ for (MachineRegisterInfo::livein_iterator II = MF.getRegInfo().livein_begin(),
+ EE = MF.getRegInfo().livein_end(); II != EE; ++II) {
+ unsigned Reg = II->first;
+
+ if (Reg == X86::EAX || Reg == X86::AX ||
+ Reg == X86::AH || Reg == X86::AL)
+ return true;
+ }
+
+ return false;
+}
+
/// emitPrologue - Push callee-saved registers onto the stack, which
/// automatically adjust the stack pointer. Adjust the stack pointer to allocate
/// space for local variables. Also emit labels used by the exception handler to
@@ -915,12 +928,12 @@
!needsStackRealignment(MF) &&
!MFI->hasVarSizedObjects() && // No dynamic alloca.
!MFI->adjustsStack() && // No calls.
- !Subtarget->isTargetWin64()) { // Win64 has no Red Zone
+ !IsWin64) { // Win64 has no Red Zone
uint64_t MinSize = X86FI->getCalleeSavedFrameSize();
if (HasFP) MinSize += SlotSize;
StackSize = std::max(MinSize, StackSize > 128 ? StackSize - 128 : 0);
MFI->setStackSize(StackSize);
- } else if (Subtarget->isTargetWin64()) {
+ } else if (IsWin64) {
// We need to always allocate 32 bytes as register spill area.
// FIXME: We might reuse these 32 bytes for leaf functions.
StackSize += 32;
@@ -1061,28 +1074,29 @@
DL = MBB.findDebugLoc(MBBI);
+ // If there is an SUB32ri of ESP immediately before this instruction, merge
+ // the two. This can be the case when tail call elimination is enabled and
+ // the callee has more arguments then the caller.
+ NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true);
+
+ // If there is an ADD32ri or SUB32ri of ESP immediately after this
+ // instruction, merge the two instructions.
+ mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
+
// Adjust stack pointer: ESP -= numbytes.
// Windows and cygwin/mingw require a prologue helper routine when allocating
// more than 4K bytes on the stack. Windows uses __chkstk and cygwin/mingw
- // uses __alloca. __alloca and the 32-bit version of __chkstk will probe
- // the stack and adjust the stack pointer in one go. The 64-bit version
- // of __chkstk is only responsible for probing the stack. The 64-bit
- // prologue is 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.
+ // uses __alloca. __alloca and the 32-bit version of __chkstk will probe the
+ // stack and adjust the stack pointer in one go. The 64-bit version of
+ // __chkstk is only responsible for probing the stack. The 64-bit prologue is
+ // 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 >= 4096 &&
(Subtarget->isTargetCygMing() || Subtarget->isTargetWin32())) {
- // Check, whether EAX is livein for this function.
- bool isEAXAlive = false;
- for (MachineRegisterInfo::livein_iterator
- II = MF.getRegInfo().livein_begin(),
- EE = MF.getRegInfo().livein_end(); (II != EE) && !isEAXAlive; ++II) {
- unsigned Reg = II->first;
- isEAXAlive = (Reg == X86::EAX || Reg == X86::AX ||
- Reg == X86::AH || Reg == X86::AL);
- }
-
+ // Check whether EAX is livein for this function.
+ bool isEAXAlive = isEAXLiveIn(MF);
const char *StackProbeSymbol =
Subtarget->isTargetWindows() ? "_chkstk" : "_alloca";
@@ -1114,19 +1128,21 @@
StackPtr, false, NumBytes - 4);
MBB.insert(MBBI, MI);
}
- } else if (NumBytes) {
- // If there is an SUB32ri of ESP immediately before this instruction, merge
- // the two. This can be the case when tail call elimination is enabled and
- // the callee has more arguments then the caller.
- NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true);
-
- // If there is an ADD32ri or SUB32ri of ESP immediately after this
- // instruction, merge the two instructions.
- mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
-
- if (NumBytes)
- emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
- }
+ } else if (NumBytes >= 4096 && Subtarget->isTargetWin64()) {
+ // Sanity check that EAX is not livein for this function. It should
+ // should not be, so throw an assert.
+ assert(!isEAXLiveIn(MF) && "EAX is livein in the Win64 case!");
+
+ // Handle the 64-bit Windows ABI case where we need to call __chkstk.
+ // Function prologue is responsible for adjusting the stack pointer.
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
+ .addImm(NumBytes);
+ BuildMI(MBB, MBBI, DL, TII.get(X86::WINCALL64pcrel32))
+ .addExternalSymbol("__chkstk")
+ .addReg(StackPtr, RegState::Define | RegState::Implicit);
+ emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
+ } else if (NumBytes)
+ emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
if ((NumBytes || PushedRegs) && needsFrameMoves) {
// Mark end of stack pointer adjustment.
Modified: llvm/trunk/test/CodeGen/X86/win_chkstk.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/win_chkstk.ll?rev=115479&r1=115478&r2=115479&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/win_chkstk.ll (original)
+++ llvm/trunk/test/CodeGen/X86/win_chkstk.ll Sun Oct 3 17:02:38 2010
@@ -1,4 +1,5 @@
; RUN: llc < %s -mtriple=i686-pc-win32 | FileCheck %s -check-prefix=WIN_X32
+; RUN: llc < %s -mtriple=x86_64-pc-win32 | FileCheck %s -check-prefix=WIN_X64
; RUN: llc < %s -mtriple=i686-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X32
; RUN: llc < %s -mtriple=x86_64-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X64
; RUN: llc < %s -mtriple=i386-pc-linux | FileCheck %s -check-prefix=LINUX
@@ -13,7 +14,7 @@
define i32 @main4k() nounwind {
entry:
; WIN_X32: calll __chkstk
-; WIN_X64: call __chkstk
+; WIN_X64: callq __chkstk
; MINGW_X32: calll __alloca
; MINGW_X64: callq _alloca
; LINUX-NOT: call __chkstk
@@ -30,7 +31,7 @@
; WIN_X32: ret
; WIN_X64: # BB#0:
-; WIN_X64-NOT: call __chkstk
+; WIN_X64-NOT: callq __chkstk
; WIN_X64: ret
; MINGW_X64: # BB#0:
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