From e4d22d59d1db39262790b6afd3521a65be2d7288 Mon Sep 17 00:00:00 2001 From: JF Bastien Date: Mon, 20 Jul 2015 22:51:32 +0000 Subject: 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 `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 llvm-svn: 242727 --- llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp | 18 ------------------ 1 file changed, 18 deletions(-) (limited to 'llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp') diff --git a/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp b/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp index 2b09b2f625d..6f364bc0577 100644 --- a/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp +++ b/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp @@ -898,24 +898,6 @@ bool PPCRegisterInfo::hasBasePointer(const MachineFunction &MF) const { 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 -- cgit v1.2.3