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https://github.com/c64scene-ar/llvm-6502.git
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966aeb5788
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135942 91177308-0d34-0410-b5e6-96231b3b80d8
646 lines
23 KiB
C++
646 lines
23 KiB
C++
//===- PPCRegisterInfo.cpp - PowerPC Register Information -------*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file contains the PowerPC implementation of the TargetRegisterInfo
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// class.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "reginfo"
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#include "PPC.h"
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#include "PPCInstrBuilder.h"
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#include "PPCMachineFunctionInfo.h"
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#include "PPCRegisterInfo.h"
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#include "PPCFrameLowering.h"
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#include "PPCSubtarget.h"
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#include "llvm/CallingConv.h"
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#include "llvm/Constants.h"
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#include "llvm/Function.h"
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#include "llvm/Type.h"
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#include "llvm/CodeGen/ValueTypes.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineModuleInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/RegisterScavenging.h"
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#include "llvm/Target/TargetFrameLowering.h"
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#include "llvm/Target/TargetInstrInfo.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetOptions.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/ADT/BitVector.h"
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#include "llvm/ADT/STLExtras.h"
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#include <cstdlib>
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#define GET_REGINFO_TARGET_DESC
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#include "PPCGenRegisterInfo.inc"
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// FIXME (64-bit): Eventually enable by default.
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namespace llvm {
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cl::opt<bool> EnablePPC32RS("enable-ppc32-regscavenger",
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cl::init(false),
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cl::desc("Enable PPC32 register scavenger"),
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cl::Hidden);
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cl::opt<bool> EnablePPC64RS("enable-ppc64-regscavenger",
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cl::init(false),
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cl::desc("Enable PPC64 register scavenger"),
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cl::Hidden);
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}
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using namespace llvm;
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// FIXME (64-bit): Should be inlined.
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bool
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PPCRegisterInfo::requiresRegisterScavenging(const MachineFunction &) const {
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return ((EnablePPC32RS && !Subtarget.isPPC64()) ||
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(EnablePPC64RS && Subtarget.isPPC64()));
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}
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PPCRegisterInfo::PPCRegisterInfo(const PPCSubtarget &ST,
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const TargetInstrInfo &tii)
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: PPCGenRegisterInfo(ST.isPPC64() ? PPC::LR8 : PPC::LR,
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ST.isPPC64() ? 0 : 1,
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ST.isPPC64() ? 0 : 1),
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Subtarget(ST), TII(tii) {
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ImmToIdxMap[PPC::LD] = PPC::LDX; ImmToIdxMap[PPC::STD] = PPC::STDX;
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ImmToIdxMap[PPC::LBZ] = PPC::LBZX; ImmToIdxMap[PPC::STB] = PPC::STBX;
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ImmToIdxMap[PPC::LHZ] = PPC::LHZX; ImmToIdxMap[PPC::LHA] = PPC::LHAX;
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ImmToIdxMap[PPC::LWZ] = PPC::LWZX; ImmToIdxMap[PPC::LWA] = PPC::LWAX;
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ImmToIdxMap[PPC::LFS] = PPC::LFSX; ImmToIdxMap[PPC::LFD] = PPC::LFDX;
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ImmToIdxMap[PPC::STH] = PPC::STHX; ImmToIdxMap[PPC::STW] = PPC::STWX;
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ImmToIdxMap[PPC::STFS] = PPC::STFSX; ImmToIdxMap[PPC::STFD] = PPC::STFDX;
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ImmToIdxMap[PPC::ADDI] = PPC::ADD4;
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// 64-bit
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ImmToIdxMap[PPC::LHA8] = PPC::LHAX8; ImmToIdxMap[PPC::LBZ8] = PPC::LBZX8;
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ImmToIdxMap[PPC::LHZ8] = PPC::LHZX8; ImmToIdxMap[PPC::LWZ8] = PPC::LWZX8;
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ImmToIdxMap[PPC::STB8] = PPC::STBX8; ImmToIdxMap[PPC::STH8] = PPC::STHX8;
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ImmToIdxMap[PPC::STW8] = PPC::STWX8; ImmToIdxMap[PPC::STDU] = PPC::STDUX;
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ImmToIdxMap[PPC::ADDI8] = PPC::ADD8; ImmToIdxMap[PPC::STD_32] = PPC::STDX_32;
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}
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/// getPointerRegClass - Return the register class to use to hold pointers.
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/// This is used for addressing modes.
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const TargetRegisterClass *
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PPCRegisterInfo::getPointerRegClass(unsigned Kind) const {
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if (Subtarget.isPPC64())
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return &PPC::G8RCRegClass;
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return &PPC::GPRCRegClass;
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}
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const unsigned*
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PPCRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
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// 32-bit Darwin calling convention.
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static const unsigned Darwin32_CalleeSavedRegs[] = {
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PPC::R13, PPC::R14, PPC::R15,
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PPC::R16, PPC::R17, PPC::R18, PPC::R19,
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PPC::R20, PPC::R21, PPC::R22, PPC::R23,
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PPC::R24, PPC::R25, PPC::R26, PPC::R27,
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PPC::R28, PPC::R29, PPC::R30, PPC::R31,
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PPC::F14, PPC::F15, PPC::F16, PPC::F17,
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PPC::F18, PPC::F19, PPC::F20, PPC::F21,
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PPC::F22, PPC::F23, PPC::F24, PPC::F25,
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PPC::F26, PPC::F27, PPC::F28, PPC::F29,
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PPC::F30, PPC::F31,
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PPC::CR2, PPC::CR3, PPC::CR4,
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PPC::V20, PPC::V21, PPC::V22, PPC::V23,
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PPC::V24, PPC::V25, PPC::V26, PPC::V27,
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PPC::V28, PPC::V29, PPC::V30, PPC::V31,
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PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
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PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
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PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
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PPC::LR, 0
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};
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// 32-bit SVR4 calling convention.
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static const unsigned SVR4_CalleeSavedRegs[] = {
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PPC::R14, PPC::R15,
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PPC::R16, PPC::R17, PPC::R18, PPC::R19,
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PPC::R20, PPC::R21, PPC::R22, PPC::R23,
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PPC::R24, PPC::R25, PPC::R26, PPC::R27,
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PPC::R28, PPC::R29, PPC::R30, PPC::R31,
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PPC::F14, PPC::F15, PPC::F16, PPC::F17,
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PPC::F18, PPC::F19, PPC::F20, PPC::F21,
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PPC::F22, PPC::F23, PPC::F24, PPC::F25,
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PPC::F26, PPC::F27, PPC::F28, PPC::F29,
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PPC::F30, PPC::F31,
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PPC::CR2, PPC::CR3, PPC::CR4,
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PPC::VRSAVE,
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PPC::V20, PPC::V21, PPC::V22, PPC::V23,
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PPC::V24, PPC::V25, PPC::V26, PPC::V27,
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PPC::V28, PPC::V29, PPC::V30, PPC::V31,
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PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
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PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
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PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
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0
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};
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// 64-bit Darwin calling convention.
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static const unsigned Darwin64_CalleeSavedRegs[] = {
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PPC::X14, PPC::X15,
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PPC::X16, PPC::X17, PPC::X18, PPC::X19,
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PPC::X20, PPC::X21, PPC::X22, PPC::X23,
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PPC::X24, PPC::X25, PPC::X26, PPC::X27,
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PPC::X28, PPC::X29, PPC::X30, PPC::X31,
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PPC::F14, PPC::F15, PPC::F16, PPC::F17,
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PPC::F18, PPC::F19, PPC::F20, PPC::F21,
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PPC::F22, PPC::F23, PPC::F24, PPC::F25,
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PPC::F26, PPC::F27, PPC::F28, PPC::F29,
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PPC::F30, PPC::F31,
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PPC::CR2, PPC::CR3, PPC::CR4,
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PPC::V20, PPC::V21, PPC::V22, PPC::V23,
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PPC::V24, PPC::V25, PPC::V26, PPC::V27,
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PPC::V28, PPC::V29, PPC::V30, PPC::V31,
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PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
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PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
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PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
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PPC::LR8, 0
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};
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// 64-bit SVR4 calling convention.
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static const unsigned SVR4_64_CalleeSavedRegs[] = {
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PPC::X14, PPC::X15,
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PPC::X16, PPC::X17, PPC::X18, PPC::X19,
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PPC::X20, PPC::X21, PPC::X22, PPC::X23,
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PPC::X24, PPC::X25, PPC::X26, PPC::X27,
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PPC::X28, PPC::X29, PPC::X30, PPC::X31,
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PPC::F14, PPC::F15, PPC::F16, PPC::F17,
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PPC::F18, PPC::F19, PPC::F20, PPC::F21,
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PPC::F22, PPC::F23, PPC::F24, PPC::F25,
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PPC::F26, PPC::F27, PPC::F28, PPC::F29,
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PPC::F30, PPC::F31,
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PPC::CR2, PPC::CR3, PPC::CR4,
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PPC::VRSAVE,
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PPC::V20, PPC::V21, PPC::V22, PPC::V23,
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PPC::V24, PPC::V25, PPC::V26, PPC::V27,
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PPC::V28, PPC::V29, PPC::V30, PPC::V31,
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PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
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PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
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PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
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0
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};
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if (Subtarget.isDarwinABI())
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return Subtarget.isPPC64() ? Darwin64_CalleeSavedRegs :
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Darwin32_CalleeSavedRegs;
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return Subtarget.isPPC64() ? SVR4_64_CalleeSavedRegs : SVR4_CalleeSavedRegs;
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}
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BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
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BitVector Reserved(getNumRegs());
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const PPCFrameLowering *PPCFI =
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static_cast<const PPCFrameLowering*>(MF.getTarget().getFrameLowering());
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Reserved.set(PPC::R0);
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Reserved.set(PPC::R1);
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Reserved.set(PPC::LR);
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Reserved.set(PPC::LR8);
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Reserved.set(PPC::RM);
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// The SVR4 ABI reserves r2 and r13
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if (Subtarget.isSVR4ABI()) {
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Reserved.set(PPC::R2); // System-reserved register
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Reserved.set(PPC::R13); // Small Data Area pointer register
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}
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// Reserve R2 on Darwin to hack around the problem of save/restore of CR
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// when the stack frame is too big to address directly; we need two regs.
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// This is a hack.
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if (Subtarget.isDarwinABI()) {
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Reserved.set(PPC::R2);
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}
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// On PPC64, r13 is the thread pointer. Never allocate this register.
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// Note that this is over conservative, as it also prevents allocation of R31
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// when the FP is not needed.
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if (Subtarget.isPPC64()) {
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Reserved.set(PPC::R13);
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Reserved.set(PPC::R31);
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if (!requiresRegisterScavenging(MF))
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Reserved.set(PPC::R0); // FIXME (64-bit): Remove
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Reserved.set(PPC::X0);
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Reserved.set(PPC::X1);
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Reserved.set(PPC::X13);
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Reserved.set(PPC::X31);
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// The 64-bit SVR4 ABI reserves r2 for the TOC pointer.
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if (Subtarget.isSVR4ABI()) {
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Reserved.set(PPC::X2);
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}
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// Reserve R2 on Darwin to hack around the problem of save/restore of CR
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// when the stack frame is too big to address directly; we need two regs.
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// This is a hack.
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if (Subtarget.isDarwinABI()) {
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Reserved.set(PPC::X2);
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}
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}
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if (PPCFI->needsFP(MF))
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Reserved.set(PPC::R31);
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return Reserved;
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}
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//===----------------------------------------------------------------------===//
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// Stack Frame Processing methods
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//===----------------------------------------------------------------------===//
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void PPCRegisterInfo::
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eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
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MachineBasicBlock::iterator I) const {
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if (GuaranteedTailCallOpt && I->getOpcode() == PPC::ADJCALLSTACKUP) {
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// Add (actually subtract) back the amount the callee popped on return.
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if (int CalleeAmt = I->getOperand(1).getImm()) {
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bool is64Bit = Subtarget.isPPC64();
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CalleeAmt *= -1;
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unsigned StackReg = is64Bit ? PPC::X1 : PPC::R1;
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unsigned TmpReg = is64Bit ? PPC::X0 : PPC::R0;
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unsigned ADDIInstr = is64Bit ? PPC::ADDI8 : PPC::ADDI;
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unsigned ADDInstr = is64Bit ? PPC::ADD8 : PPC::ADD4;
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unsigned LISInstr = is64Bit ? PPC::LIS8 : PPC::LIS;
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unsigned ORIInstr = is64Bit ? PPC::ORI8 : PPC::ORI;
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MachineInstr *MI = I;
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DebugLoc dl = MI->getDebugLoc();
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if (isInt<16>(CalleeAmt)) {
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BuildMI(MBB, I, dl, TII.get(ADDIInstr), StackReg).addReg(StackReg).
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addImm(CalleeAmt);
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} else {
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MachineBasicBlock::iterator MBBI = I;
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BuildMI(MBB, MBBI, dl, TII.get(LISInstr), TmpReg)
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.addImm(CalleeAmt >> 16);
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BuildMI(MBB, MBBI, dl, TII.get(ORIInstr), TmpReg)
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.addReg(TmpReg, RegState::Kill)
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.addImm(CalleeAmt & 0xFFFF);
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BuildMI(MBB, MBBI, dl, TII.get(ADDInstr))
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.addReg(StackReg)
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.addReg(StackReg)
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.addReg(TmpReg);
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}
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}
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}
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// Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions.
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MBB.erase(I);
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}
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/// findScratchRegister - Find a 'free' PPC register. Try for a call-clobbered
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/// register first and then a spilled callee-saved register if that fails.
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static
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unsigned findScratchRegister(MachineBasicBlock::iterator II, RegScavenger *RS,
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const TargetRegisterClass *RC, int SPAdj) {
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assert(RS && "Register scavenging must be on");
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unsigned Reg = RS->FindUnusedReg(RC);
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// FIXME: move ARM callee-saved reg scan to target independent code, then
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// search for already spilled CS register here.
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if (Reg == 0)
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Reg = RS->scavengeRegister(RC, II, SPAdj);
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return Reg;
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}
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/// lowerDynamicAlloc - Generate the code for allocating an object in the
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/// current frame. The sequence of code with be in the general form
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///
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/// addi R0, SP, \#frameSize ; get the address of the previous frame
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/// stwxu R0, SP, Rnegsize ; add and update the SP with the negated size
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/// addi Rnew, SP, \#maxCalFrameSize ; get the top of the allocation
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///
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void PPCRegisterInfo::lowerDynamicAlloc(MachineBasicBlock::iterator II,
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int SPAdj, RegScavenger *RS) const {
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// Get the instruction.
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MachineInstr &MI = *II;
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// Get the instruction's basic block.
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MachineBasicBlock &MBB = *MI.getParent();
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// Get the basic block's function.
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MachineFunction &MF = *MBB.getParent();
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// Get the frame info.
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MachineFrameInfo *MFI = MF.getFrameInfo();
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// Determine whether 64-bit pointers are used.
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bool LP64 = Subtarget.isPPC64();
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DebugLoc dl = MI.getDebugLoc();
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// Get the maximum call stack size.
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unsigned maxCallFrameSize = MFI->getMaxCallFrameSize();
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// Get the total frame size.
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unsigned FrameSize = MFI->getStackSize();
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// Get stack alignments.
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unsigned TargetAlign = MF.getTarget().getFrameLowering()->getStackAlignment();
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unsigned MaxAlign = MFI->getMaxAlignment();
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if (MaxAlign > TargetAlign)
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report_fatal_error("Dynamic alloca with large aligns not supported");
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// Determine the previous frame's address. If FrameSize can't be
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// represented as 16 bits or we need special alignment, then we load the
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// previous frame's address from 0(SP). Why not do an addis of the hi?
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// Because R0 is our only safe tmp register and addi/addis treat R0 as zero.
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// Constructing the constant and adding would take 3 instructions.
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// Fortunately, a frame greater than 32K is rare.
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const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
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const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
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const TargetRegisterClass *RC = LP64 ? G8RC : GPRC;
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// FIXME (64-bit): Use "findScratchRegister"
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unsigned Reg;
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if (requiresRegisterScavenging(MF))
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Reg = findScratchRegister(II, RS, RC, SPAdj);
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else
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Reg = PPC::R0;
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if (MaxAlign < TargetAlign && isInt<16>(FrameSize)) {
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BuildMI(MBB, II, dl, TII.get(PPC::ADDI), Reg)
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.addReg(PPC::R31)
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.addImm(FrameSize);
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} else if (LP64) {
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if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Use "true" part.
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BuildMI(MBB, II, dl, TII.get(PPC::LD), Reg)
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.addImm(0)
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.addReg(PPC::X1);
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else
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BuildMI(MBB, II, dl, TII.get(PPC::LD), PPC::X0)
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.addImm(0)
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.addReg(PPC::X1);
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} else {
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BuildMI(MBB, II, dl, TII.get(PPC::LWZ), Reg)
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.addImm(0)
|
|
.addReg(PPC::R1);
|
|
}
|
|
|
|
// Grow the stack and update the stack pointer link, then determine the
|
|
// address of new allocated space.
|
|
if (LP64) {
|
|
if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Use "true" part.
|
|
BuildMI(MBB, II, dl, TII.get(PPC::STDUX))
|
|
.addReg(Reg, RegState::Kill)
|
|
.addReg(PPC::X1)
|
|
.addReg(MI.getOperand(1).getReg());
|
|
else
|
|
BuildMI(MBB, II, dl, TII.get(PPC::STDUX))
|
|
.addReg(PPC::X0, RegState::Kill)
|
|
.addReg(PPC::X1)
|
|
.addReg(MI.getOperand(1).getReg());
|
|
|
|
if (!MI.getOperand(1).isKill())
|
|
BuildMI(MBB, II, dl, TII.get(PPC::ADDI8), MI.getOperand(0).getReg())
|
|
.addReg(PPC::X1)
|
|
.addImm(maxCallFrameSize);
|
|
else
|
|
// Implicitly kill the register.
|
|
BuildMI(MBB, II, dl, TII.get(PPC::ADDI8), MI.getOperand(0).getReg())
|
|
.addReg(PPC::X1)
|
|
.addImm(maxCallFrameSize)
|
|
.addReg(MI.getOperand(1).getReg(), RegState::ImplicitKill);
|
|
} else {
|
|
BuildMI(MBB, II, dl, TII.get(PPC::STWUX))
|
|
.addReg(Reg, RegState::Kill)
|
|
.addReg(PPC::R1)
|
|
.addReg(MI.getOperand(1).getReg());
|
|
|
|
if (!MI.getOperand(1).isKill())
|
|
BuildMI(MBB, II, dl, TII.get(PPC::ADDI), MI.getOperand(0).getReg())
|
|
.addReg(PPC::R1)
|
|
.addImm(maxCallFrameSize);
|
|
else
|
|
// Implicitly kill the register.
|
|
BuildMI(MBB, II, dl, TII.get(PPC::ADDI), MI.getOperand(0).getReg())
|
|
.addReg(PPC::R1)
|
|
.addImm(maxCallFrameSize)
|
|
.addReg(MI.getOperand(1).getReg(), RegState::ImplicitKill);
|
|
}
|
|
|
|
// Discard the DYNALLOC instruction.
|
|
MBB.erase(II);
|
|
}
|
|
|
|
/// lowerCRSpilling - Generate the code for spilling a CR register. Instead of
|
|
/// reserving a whole register (R0), we scrounge for one here. This generates
|
|
/// code like this:
|
|
///
|
|
/// mfcr rA ; Move the conditional register into GPR rA.
|
|
/// rlwinm rA, rA, SB, 0, 31 ; Shift the bits left so they are in CR0's slot.
|
|
/// stw rA, FI ; Store rA to the frame.
|
|
///
|
|
void PPCRegisterInfo::lowerCRSpilling(MachineBasicBlock::iterator II,
|
|
unsigned FrameIndex, int SPAdj,
|
|
RegScavenger *RS) const {
|
|
// Get the instruction.
|
|
MachineInstr &MI = *II; // ; SPILL_CR <SrcReg>, <offset>, <FI>
|
|
// Get the instruction's basic block.
|
|
MachineBasicBlock &MBB = *MI.getParent();
|
|
DebugLoc dl = MI.getDebugLoc();
|
|
|
|
const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
|
|
const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
|
|
const TargetRegisterClass *RC = Subtarget.isPPC64() ? G8RC : GPRC;
|
|
unsigned Reg = findScratchRegister(II, RS, RC, SPAdj);
|
|
unsigned SrcReg = MI.getOperand(0).getReg();
|
|
bool LP64 = Subtarget.isPPC64();
|
|
|
|
// We need to store the CR in the low 4-bits of the saved value. First, issue
|
|
// an MFCRpsued to save all of the CRBits and, if needed, kill the SrcReg.
|
|
BuildMI(MBB, II, dl, TII.get(PPC::MFCRpseud), Reg)
|
|
.addReg(SrcReg, getKillRegState(MI.getOperand(0).isKill()));
|
|
|
|
// If the saved register wasn't CR0, shift the bits left so that they are in
|
|
// CR0's slot.
|
|
if (SrcReg != PPC::CR0)
|
|
// rlwinm rA, rA, ShiftBits, 0, 31.
|
|
BuildMI(MBB, II, dl, TII.get(PPC::RLWINM), Reg)
|
|
.addReg(Reg, RegState::Kill)
|
|
.addImm(getPPCRegisterNumbering(SrcReg) * 4)
|
|
.addImm(0)
|
|
.addImm(31);
|
|
|
|
addFrameReference(BuildMI(MBB, II, dl, TII.get(LP64 ? PPC::STW8 : PPC::STW))
|
|
.addReg(Reg, getKillRegState(MI.getOperand(1).getImm())),
|
|
FrameIndex);
|
|
|
|
// Discard the pseudo instruction.
|
|
MBB.erase(II);
|
|
}
|
|
|
|
void
|
|
PPCRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
|
|
int SPAdj, RegScavenger *RS) const {
|
|
assert(SPAdj == 0 && "Unexpected");
|
|
|
|
// Get the instruction.
|
|
MachineInstr &MI = *II;
|
|
// Get the instruction's basic block.
|
|
MachineBasicBlock &MBB = *MI.getParent();
|
|
// Get the basic block's function.
|
|
MachineFunction &MF = *MBB.getParent();
|
|
// Get the frame info.
|
|
MachineFrameInfo *MFI = MF.getFrameInfo();
|
|
const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
|
|
DebugLoc dl = MI.getDebugLoc();
|
|
|
|
// Find out which operand is the frame index.
|
|
unsigned FIOperandNo = 0;
|
|
while (!MI.getOperand(FIOperandNo).isFI()) {
|
|
++FIOperandNo;
|
|
assert(FIOperandNo != MI.getNumOperands() &&
|
|
"Instr doesn't have FrameIndex operand!");
|
|
}
|
|
// Take into account whether it's an add or mem instruction
|
|
unsigned OffsetOperandNo = (FIOperandNo == 2) ? 1 : 2;
|
|
if (MI.isInlineAsm())
|
|
OffsetOperandNo = FIOperandNo-1;
|
|
|
|
// Get the frame index.
|
|
int FrameIndex = MI.getOperand(FIOperandNo).getIndex();
|
|
|
|
// Get the frame pointer save index. Users of this index are primarily
|
|
// DYNALLOC instructions.
|
|
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
|
|
int FPSI = FI->getFramePointerSaveIndex();
|
|
// Get the instruction opcode.
|
|
unsigned OpC = MI.getOpcode();
|
|
|
|
// Special case for dynamic alloca.
|
|
if (FPSI && FrameIndex == FPSI &&
|
|
(OpC == PPC::DYNALLOC || OpC == PPC::DYNALLOC8)) {
|
|
lowerDynamicAlloc(II, SPAdj, RS);
|
|
return;
|
|
}
|
|
|
|
// Special case for pseudo-op SPILL_CR.
|
|
if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Enable by default.
|
|
if (OpC == PPC::SPILL_CR) {
|
|
lowerCRSpilling(II, FrameIndex, SPAdj, RS);
|
|
return;
|
|
}
|
|
|
|
// Replace the FrameIndex with base register with GPR1 (SP) or GPR31 (FP).
|
|
MI.getOperand(FIOperandNo).ChangeToRegister(TFI->hasFP(MF) ?
|
|
PPC::R31 : PPC::R1,
|
|
false);
|
|
|
|
// Figure out if the offset in the instruction is shifted right two bits. This
|
|
// is true for instructions like "STD", which the machine implicitly adds two
|
|
// low zeros to.
|
|
bool isIXAddr = false;
|
|
switch (OpC) {
|
|
case PPC::LWA:
|
|
case PPC::LD:
|
|
case PPC::STD:
|
|
case PPC::STD_32:
|
|
isIXAddr = true;
|
|
break;
|
|
}
|
|
|
|
// Now add the frame object offset to the offset from r1.
|
|
int Offset = MFI->getObjectOffset(FrameIndex);
|
|
if (!isIXAddr)
|
|
Offset += MI.getOperand(OffsetOperandNo).getImm();
|
|
else
|
|
Offset += MI.getOperand(OffsetOperandNo).getImm() << 2;
|
|
|
|
// If we're not using a Frame Pointer that has been set to the value of the
|
|
// SP before having the stack size subtracted from it, then add the stack size
|
|
// to Offset to get the correct offset.
|
|
// Naked functions have stack size 0, although getStackSize may not reflect that
|
|
// because we didn't call all the pieces that compute it for naked functions.
|
|
if (!MF.getFunction()->hasFnAttr(Attribute::Naked))
|
|
Offset += MFI->getStackSize();
|
|
|
|
// If we can, encode the offset directly into the instruction. If this is a
|
|
// normal PPC "ri" instruction, any 16-bit value can be safely encoded. If
|
|
// this is a PPC64 "ix" instruction, only a 16-bit value with the low two bits
|
|
// clear can be encoded. This is extremely uncommon, because normally you
|
|
// only "std" to a stack slot that is at least 4-byte aligned, but it can
|
|
// happen in invalid code.
|
|
if (isInt<16>(Offset) && (!isIXAddr || (Offset & 3) == 0)) {
|
|
if (isIXAddr)
|
|
Offset >>= 2; // The actual encoded value has the low two bits zero.
|
|
MI.getOperand(OffsetOperandNo).ChangeToImmediate(Offset);
|
|
return;
|
|
}
|
|
|
|
// The offset doesn't fit into a single register, scavenge one to build the
|
|
// offset in.
|
|
// FIXME: figure out what SPAdj is doing here.
|
|
|
|
// FIXME (64-bit): Use "findScratchRegister".
|
|
unsigned SReg;
|
|
if (requiresRegisterScavenging(MF))
|
|
SReg = findScratchRegister(II, RS, &PPC::GPRCRegClass, SPAdj);
|
|
else
|
|
SReg = PPC::R0;
|
|
|
|
// Insert a set of rA with the full offset value before the ld, st, or add
|
|
BuildMI(MBB, II, dl, TII.get(PPC::LIS), SReg)
|
|
.addImm(Offset >> 16);
|
|
BuildMI(MBB, II, dl, TII.get(PPC::ORI), SReg)
|
|
.addReg(SReg, RegState::Kill)
|
|
.addImm(Offset);
|
|
|
|
// Convert into indexed form of the instruction:
|
|
//
|
|
// sth 0:rA, 1:imm 2:(rB) ==> sthx 0:rA, 2:rB, 1:r0
|
|
// addi 0:rA 1:rB, 2, imm ==> add 0:rA, 1:rB, 2:r0
|
|
unsigned OperandBase;
|
|
|
|
if (OpC != TargetOpcode::INLINEASM) {
|
|
assert(ImmToIdxMap.count(OpC) &&
|
|
"No indexed form of load or store available!");
|
|
unsigned NewOpcode = ImmToIdxMap.find(OpC)->second;
|
|
MI.setDesc(TII.get(NewOpcode));
|
|
OperandBase = 1;
|
|
} else {
|
|
OperandBase = OffsetOperandNo;
|
|
}
|
|
|
|
unsigned StackReg = MI.getOperand(FIOperandNo).getReg();
|
|
MI.getOperand(OperandBase).ChangeToRegister(StackReg, false);
|
|
MI.getOperand(OperandBase + 1).ChangeToRegister(SReg, false);
|
|
}
|
|
|
|
unsigned PPCRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
|
|
const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
|
|
|
|
if (!Subtarget.isPPC64())
|
|
return TFI->hasFP(MF) ? PPC::R31 : PPC::R1;
|
|
else
|
|
return TFI->hasFP(MF) ? PPC::X31 : PPC::X1;
|
|
}
|
|
|
|
unsigned PPCRegisterInfo::getEHExceptionRegister() const {
|
|
return !Subtarget.isPPC64() ? PPC::R3 : PPC::X3;
|
|
}
|
|
|
|
unsigned PPCRegisterInfo::getEHHandlerRegister() const {
|
|
return !Subtarget.isPPC64() ? PPC::R4 : PPC::X4;
|
|
}
|