[llvm] r242727 - Targets: commonize some stack realignment code
JF Bastien
jfb at google.com
Mon Jul 20 15:51:32 PDT 2015
Author: jfb
Date: Mon Jul 20 17:51:32 2015
New Revision: 242727
URL: http://llvm.org/viewvc/llvm-project?rev=242727&view=rev
Log:
Targets: commonize some stack realignment code
This patch does the following:
* Fix FIXME on `needsStackRealignment`: it is now shared between multiple targets, implemented in `TargetRegisterInfo`, and isn't `virtual` anymore. This will break out-of-tree targets, silently if they used `virtual` and with a build error if they used `override`.
* Factor out `canRealignStack` as a `virtual` function on `TargetRegisterInfo`, by default only looks for the `no-realign-stack` function attribute.
Multiple targets duplicated the same `needsStackRealignment` code:
- Aarch64.
- ARM.
- Mips almost: had extra `DEBUG` diagnostic, which the default implementation now has.
- PowerPC.
- WebAssembly.
- x86 almost: has an extra `-force-align-stack` option, which the default implementation now has.
The default implementation of `needsStackRealignment` used to just return `false`. My current patch changes the behavior by simply using the above shared behavior. This affects:
- AMDGPU
- BPF
- CppBackend
- MSP430
- NVPTX
- Sparc
- SystemZ
- XCore
- Out-of-tree targets
This is a breaking change! `make check` passes.
The only implementation of the `virtual` function (besides the slight different in x86) was Hexagon (which did `MF.getFrameInfo()->getMaxAlignment() > 8`), and potentially some out-of-tree targets. Hexagon now uses the default implementation.
`needsStackRealignment` was being overwritten in `<Target>GenRegisterInfo.inc`, to return `false` as the default also did. That was odd and is now gone.
Reviewers: sunfish
Subscribers: aemerson, llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11160
Added:
llvm/trunk/test/CodeGen/Generic/ForceStackAlign.ll
Modified:
llvm/trunk/include/llvm/Target/TargetRegisterInfo.h
llvm/trunk/lib/CodeGen/TargetRegisterInfo.cpp
llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.cpp
llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.h
llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp
llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.h
llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.cpp
llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.h
llvm/trunk/lib/Target/Mips/MipsRegisterInfo.cpp
llvm/trunk/lib/Target/Mips/MipsRegisterInfo.h
llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp
llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.h
llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp
llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.h
llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp
llvm/trunk/lib/Target/X86/X86RegisterInfo.h
llvm/trunk/utils/TableGen/RegisterInfoEmitter.cpp
Modified: llvm/trunk/include/llvm/Target/TargetRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetRegisterInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -21,6 +21,7 @@
#include "llvm/CodeGen/MachineValueType.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/Support/CommandLine.h"
#include <cassert>
#include <functional>
@@ -34,6 +35,8 @@ class VirtRegMap;
class raw_ostream;
class LiveRegMatrix;
+extern cl::opt<bool> ForceStackAlign;
+
class TargetRegisterClass {
public:
typedef const MCPhysReg* iterator;
@@ -784,12 +787,14 @@ public:
return false;
}
+ /// canRealignStack - true if the stack can be realigned for the target.
+ virtual bool canRealignStack(const MachineFunction &MF) const;
+
/// 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;
- }
+ /// for. This cannot be overriden by the target, but canRealignStack can be
+ /// overriden.
+ bool needsStackRealignment(const MachineFunction &MF) const;
/// getFrameIndexInstrOffset - Get the offset from the referenced frame
/// index in the instruction, if there is one.
Modified: llvm/trunk/lib/CodeGen/TargetRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TargetRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/TargetRegisterInfo.cpp (original)
+++ llvm/trunk/lib/CodeGen/TargetRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -11,13 +11,26 @@
//
//===----------------------------------------------------------------------===//
-#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/ADT/BitVector.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/VirtRegMap.h"
+#include "llvm/IR/Function.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetFrameLowering.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+
+#define DEBUG_TYPE "target-reg-info"
+
+namespace llvm {
+cl::opt<bool>
+ ForceStackAlign("force-align-stack",
+ cl::desc("Force align the stack to the minimum alignment"
+ " needed for the function."),
+ cl::init(false), cl::Hidden);
+} // end namespace llvm
using namespace llvm;
@@ -296,6 +309,26 @@ TargetRegisterInfo::getRegAllocationHint
Hints.push_back(Phys);
}
+bool TargetRegisterInfo::canRealignStack(const MachineFunction &MF) const {
+ return !MF.getFunction()->hasFnAttribute("no-realign-stack");
+}
+
+bool TargetRegisterInfo::needsStackRealignment(
+ const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
+ const Function *F = MF.getFunction();
+ unsigned StackAlign = TFI->getStackAlignment();
+ bool requiresRealignment = ((MFI->getMaxAlignment() > StackAlign) ||
+ F->hasFnAttribute(Attribute::StackAlignment));
+ if (ForceStackAlign || requiresRealignment) {
+ if (canRealignStack(MF))
+ return true;
+ DEBUG(dbgs() << "Can't realign function's stack: " << F->getName() << "\n");
+ }
+ return false;
+}
+
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void
TargetRegisterInfo::dumpReg(unsigned Reg, unsigned SubRegIndex,
Modified: llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -186,29 +186,6 @@ bool AArch64RegisterInfo::hasBasePointer
return false;
}
-bool AArch64RegisterInfo::canRealignStack(const MachineFunction &MF) const {
-
- if (MF.getFunction()->hasFnAttribute("no-realign-stack"))
- return false;
-
- return true;
-}
-
-// FIXME: share this with other backends with identical implementation?
-bool
-AArch64RegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const AArch64FrameLowering *TFI = getFrameLowering(MF);
- const Function *F = MF.getFunction();
- unsigned StackAlign = TFI->getStackAlignment();
- bool requiresRealignment =
- ((MFI->getMaxAlignment() > StackAlign) ||
- F->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
- Attribute::StackAlignment));
-
- return requiresRealignment && canRealignStack(MF);
-}
-
unsigned
AArch64RegisterInfo::getFrameRegister(const MachineFunction &MF) const {
const AArch64FrameLowering *TFI = getFrameLowering(MF);
Modified: llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.h (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64RegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -93,9 +93,6 @@ public:
unsigned getRegPressureLimit(const TargetRegisterClass *RC,
MachineFunction &MF) const override;
- // Base pointer (stack realignment) support.
- bool canRealignStack(const MachineFunction &MF) const;
- bool needsStackRealignment(const MachineFunction &MF) const override;
};
} // end namespace llvm
Modified: llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -339,7 +339,7 @@ bool ARMBaseRegisterInfo::canRealignStac
// 1. Dynamic stack realignment is explicitly disabled,
// 2. This is a Thumb1 function (it's not useful, so we don't bother), or
// 3. There are VLAs in the function and the base pointer is disabled.
- if (MF.getFunction()->hasFnAttribute("no-realign-stack"))
+ if (!TargetRegisterInfo::canRealignStack(MF))
return false;
if (AFI->isThumb1OnlyFunction())
return false;
@@ -357,18 +357,6 @@ bool ARMBaseRegisterInfo::canRealignStac
}
bool ARMBaseRegisterInfo::
-needsStackRealignment(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const ARMFrameLowering *TFI = getFrameLowering(MF);
- const Function *F = MF.getFunction();
- unsigned StackAlign = TFI->getStackAlignment();
- bool requiresRealignment = ((MFI->getMaxAlignment() > StackAlign) ||
- F->hasFnAttribute(Attribute::StackAlignment));
-
- return requiresRealignment && canRealignStack(MF);
-}
-
-bool ARMBaseRegisterInfo::
cannotEliminateFrame(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
if (MF.getTarget().Options.DisableFramePointerElim(MF) && MFI->adjustsStack())
Modified: llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.h (original)
+++ llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -134,8 +134,7 @@ public:
bool hasBasePointer(const MachineFunction &MF) const;
- bool canRealignStack(const MachineFunction &MF) const;
- bool needsStackRealignment(const MachineFunction &MF) const override;
+ bool canRealignStack(const MachineFunction &MF) const override;
int64_t getFrameIndexInstrOffset(const MachineInstr *MI,
int Idx) const override;
bool needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const override;
Modified: llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -245,13 +245,6 @@ HexagonRegisterInfo::useFPForScavengingI
}
-bool
-HexagonRegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- return MFI->getMaxAlignment() > 8;
-}
-
-
unsigned HexagonRegisterInfo::getFirstCallerSavedNonParamReg() const {
return Hexagon::R6;
}
Modified: llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.h (original)
+++ llvm/trunk/lib/Target/Hexagon/HexagonRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -63,8 +63,6 @@ public:
return true;
}
- bool needsStackRealignment(const MachineFunction &MF) const override;
-
/// Returns true if the frame pointer is valid.
bool useFPForScavengingIndex(const MachineFunction &MF) const override;
Modified: llvm/trunk/lib/Target/Mips/MipsRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MipsRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Mips/MipsRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/Mips/MipsRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -284,6 +284,16 @@ getFrameRegister(const MachineFunction &
}
bool MipsRegisterInfo::canRealignStack(const MachineFunction &MF) const {
+ // Avoid realigning functions that explicitly do not want to be realigned.
+ // Normally, we should report an error when a function should be dynamically
+ // realigned but also has the attribute no-realign-stack. Unfortunately,
+ // with this attribute, MachineFrameInfo clamps each new object's alignment
+ // to that of the stack's alignment as specified by the ABI. As a result,
+ // the information of whether we have objects with larger alignment
+ // requirement than the stack's alignment is already lost at this point.
+ if (!TargetRegisterInfo::canRealignStack(MF))
+ return false;
+
const MipsSubtarget &Subtarget = MF.getSubtarget<MipsSubtarget>();
unsigned FP = Subtarget.isGP32bit() ? Mips::FP : Mips::FP_64;
unsigned BP = Subtarget.isGP32bit() ? Mips::S7 : Mips::S7_64;
@@ -306,42 +316,3 @@ bool MipsRegisterInfo::canRealignStack(c
// sized objects.
return MF.getRegInfo().canReserveReg(BP);
}
-
-bool MipsRegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
- const MipsSubtarget &Subtarget = MF.getSubtarget<MipsSubtarget>();
- const MachineFrameInfo *MFI = MF.getFrameInfo();
-
- bool CanRealign = canRealignStack(MF);
-
- // Avoid realigning functions that explicitly do not want to be realigned.
- // Normally, we should report an error when a function should be dynamically
- // realigned but also has the attribute no-realign-stack. Unfortunately,
- // with this attribute, MachineFrameInfo clamps each new object's alignment
- // to that of the stack's alignment as specified by the ABI. As a result,
- // the information of whether we have objects with larger alignment
- // requirement than the stack's alignment is already lost at this point.
- if (MF.getFunction()->hasFnAttribute("no-realign-stack"))
- return false;
-
- const Function *F = MF.getFunction();
- if (F->hasFnAttribute(Attribute::StackAlignment)) {
-#ifdef DEBUG
- if (!CanRealign)
- DEBUG(dbgs() << "It's not possible to realign the stack of the function: "
- << F->getName() << "\n");
-#endif
- return CanRealign;
- }
-
- unsigned StackAlignment = Subtarget.getFrameLowering()->getStackAlignment();
- if (MFI->getMaxAlignment() > StackAlignment) {
-#ifdef DEBUG
- if (!CanRealign)
- DEBUG(dbgs() << "It's not possible to realign the stack of the function: "
- << F->getName() << "\n");
-#endif
- return CanRealign;
- }
-
- return false;
-}
Modified: llvm/trunk/lib/Target/Mips/MipsRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MipsRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Mips/MipsRegisterInfo.h (original)
+++ llvm/trunk/lib/Target/Mips/MipsRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -61,9 +61,7 @@ public:
RegScavenger *RS = nullptr) const;
// Stack realignment queries.
- bool canRealignStack(const MachineFunction &MF) const;
-
- bool needsStackRealignment(const MachineFunction &MF) const override;
+ bool canRealignStack(const MachineFunction &MF) const override;
/// Debug information queries.
unsigned getFrameRegister(const MachineFunction &MF) const override;
Modified: llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -898,24 +898,6 @@ bool PPCRegisterInfo::hasBasePointer(con
return needsStackRealignment(MF);
}
-bool PPCRegisterInfo::canRealignStack(const MachineFunction &MF) const {
- if (MF.getFunction()->hasFnAttribute("no-realign-stack"))
- return false;
-
- return true;
-}
-
-bool PPCRegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
- const PPCFrameLowering *TFI = getFrameLowering(MF);
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const Function *F = MF.getFunction();
- unsigned StackAlign = TFI->getStackAlignment();
- bool requiresRealignment = ((MFI->getMaxAlignment() > StackAlign) ||
- F->hasFnAttribute(Attribute::StackAlignment));
-
- return requiresRealignment && canRealignStack(MF);
-}
-
/// Returns true if the instruction's frame index
/// reference would be better served by a base register other than FP
/// or SP. Used by LocalStackFrameAllocation to determine which frame index
Modified: llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.h (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -136,8 +136,6 @@ public:
// Base pointer (stack realignment) support.
unsigned getBaseRegister(const MachineFunction &MF) const;
bool hasBasePointer(const MachineFunction &MF) const;
- bool canRealignStack(const MachineFunction &MF) const;
- bool needsStackRealignment(const MachineFunction &MF) const override;
};
} // end namespace llvm
Modified: llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -66,22 +66,3 @@ WebAssemblyRegisterInfo::getFrameRegiste
const WebAssemblyFrameLowering *TFI = getFrameLowering(MF);
return Regs[TFI->hasFP(MF)][TT.isArch64Bit()];
}
-
-bool WebAssemblyRegisterInfo::canRealignStack(const MachineFunction &MF) const {
- return !MF.getFunction()->hasFnAttribute("no-realign-stack");
-}
-
-// FIXME: share this with other backends with identical implementation?
-bool WebAssemblyRegisterInfo::needsStackRealignment(
- const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const WebAssemblyFrameLowering *TFI = getFrameLowering(MF);
- const Function *F = MF.getFunction();
- unsigned StackAlign = TFI->getStackAlignment();
- bool requiresRealignment =
- ((MFI->getMaxAlignment() > StackAlign) ||
- F->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
- Attribute::StackAlignment));
-
- return requiresRealignment && canRealignStack(MF);
-}
Modified: llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.h (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyRegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -41,10 +41,6 @@ public:
// Debug information queries.
unsigned getFrameRegister(const MachineFunction &MF) const override;
-
- // Base pointer (stack realignment) support.
- bool canRealignStack(const MachineFunction &MF) const;
- bool needsStackRealignment(const MachineFunction &MF) const override;
};
} // end namespace llvm
Modified: llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FrameLowering.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FrameLowering.cpp Mon Jul 20 17:51:32 2015
@@ -27,16 +27,12 @@
#include "llvm/IR/Function.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCSymbol.h"
-#include "llvm/Support/CommandLine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/Debug.h"
#include <cstdlib>
using namespace llvm;
-// FIXME: completely move here.
-extern cl::opt<bool> ForceStackAlign;
-
X86FrameLowering::X86FrameLowering(const X86Subtarget &STI,
unsigned StackAlignOverride)
: TargetFrameLowering(StackGrowsDown, StackAlignOverride,
Modified: llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp Mon Jul 20 17:51:32 2015
@@ -44,12 +44,6 @@ using namespace llvm;
#define GET_REGINFO_TARGET_DESC
#include "X86GenRegisterInfo.inc"
-cl::opt<bool>
-ForceStackAlign("force-align-stack",
- cl::desc("Force align the stack to the minimum alignment"
- " needed for the function."),
- cl::init(false), cl::Hidden);
-
static cl::opt<bool>
EnableBasePointer("x86-use-base-pointer", cl::Hidden, cl::init(true),
cl::desc("Enable use of a base pointer for complex stack frames"));
@@ -457,7 +451,7 @@ bool X86RegisterInfo::hasBasePointer(con
}
bool X86RegisterInfo::canRealignStack(const MachineFunction &MF) const {
- if (MF.getFunction()->hasFnAttribute("no-realign-stack"))
+ if (!TargetRegisterInfo::canRealignStack(MF))
return false;
const MachineFrameInfo *MFI = MF.getFrameInfo();
@@ -475,21 +469,6 @@ bool X86RegisterInfo::canRealignStack(co
return true;
}
-bool X86RegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const X86FrameLowering *TFI = getFrameLowering(MF);
- const Function *F = MF.getFunction();
- unsigned StackAlign = TFI->getStackAlignment();
- bool requiresRealignment = ((MFI->getMaxAlignment() > StackAlign) ||
- F->hasFnAttribute(Attribute::StackAlignment));
-
- // If we've requested that we force align the stack do so now.
- if (ForceStackAlign)
- return canRealignStack(MF);
-
- return requiresRealignment && canRealignStack(MF);
-}
-
bool X86RegisterInfo::hasReservedSpillSlot(const MachineFunction &MF,
unsigned Reg, int &FrameIdx) const {
// Since X86 defines assignCalleeSavedSpillSlots which always return true
Modified: llvm/trunk/lib/Target/X86/X86RegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.h?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86RegisterInfo.h (original)
+++ llvm/trunk/lib/Target/X86/X86RegisterInfo.h Mon Jul 20 17:51:32 2015
@@ -108,9 +108,7 @@ public:
bool hasBasePointer(const MachineFunction &MF) const;
- bool canRealignStack(const MachineFunction &MF) const;
-
- bool needsStackRealignment(const MachineFunction &MF) const override;
+ bool canRealignStack(const MachineFunction &MF) const override;
bool hasReservedSpillSlot(const MachineFunction &MF, unsigned Reg,
int &FrameIdx) const override;
Added: llvm/trunk/test/CodeGen/Generic/ForceStackAlign.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Generic/ForceStackAlign.ll?rev=242727&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Generic/ForceStackAlign.ll (added)
+++ llvm/trunk/test/CodeGen/Generic/ForceStackAlign.ll Mon Jul 20 17:51:32 2015
@@ -0,0 +1,27 @@
+; Check that stack alignment can be forced. Individual targets should test their
+; specific implementation details.
+
+; RUN: llc < %s -force-align-stack -stack-alignment=32 | FileCheck %s
+; CHECK-LABEL: @f
+; CHECK-LABEL: @g
+
+define i32 @f(i8* %p) nounwind {
+entry:
+ %0 = load i8, i8* %p
+ %conv = sext i8 %0 to i32
+ ret i32 %conv
+}
+
+define i64 @g(i32 %i) nounwind {
+entry:
+ br label %if.then
+
+if.then:
+ %0 = alloca i8, i32 %i
+ call void @llvm.memset.p0i8.i32(i8* %0, i8 0, i32 %i, i32 1, i1 false)
+ %call = call i32 @f(i8* %0)
+ %conv = sext i32 %call to i64
+ ret i64 %conv
+}
+
+declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i32, i1) nounwind
Modified: llvm/trunk/utils/TableGen/RegisterInfoEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/utils/TableGen/RegisterInfoEmitter.cpp?rev=242727&r1=242726&r2=242727&view=diff
==============================================================================
--- llvm/trunk/utils/TableGen/RegisterInfoEmitter.cpp (original)
+++ llvm/trunk/utils/TableGen/RegisterInfoEmitter.cpp Mon Jul 20 17:51:32 2015
@@ -1074,9 +1074,7 @@ RegisterInfoEmitter::runTargetHeader(raw
OS << "struct " << ClassName << " : public TargetRegisterInfo {\n"
<< " explicit " << ClassName
- << "(unsigned RA, unsigned D = 0, unsigned E = 0, unsigned PC = 0);\n"
- << " bool needsStackRealignment(const MachineFunction &) const override\n"
- << " { return false; }\n";
+ << "(unsigned RA, unsigned D = 0, unsigned E = 0, unsigned PC = 0);\n";
if (!RegBank.getSubRegIndices().empty()) {
OS << " unsigned composeSubRegIndicesImpl"
<< "(unsigned, unsigned) const override;\n"
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