-//===- ARMBaseRegisterInfo.cpp - ARM Register Information -------*- C++ -*-===//
+//===-- ARMBaseRegisterInfo.cpp - ARM Register Information ----------------===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
+#include "ARMBaseRegisterInfo.h"
#include "ARM.h"
#include "ARMBaseInstrInfo.h"
-#include "ARMBaseRegisterInfo.h"
#include "ARMFrameLowering.h"
-#include "ARMInstrInfo.h"
#include "ARMMachineFunctionInfo.h"
#include "ARMSubtarget.h"
#include "MCTargetDesc/ARMAddressingModes.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/LLVMContext.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
+#include "llvm/CodeGen/VirtRegMap.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
-#include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/CommandLine.h"
+
+#define DEBUG_TYPE "arm-register-info"
#define GET_REGINFO_TARGET_DESC
#include "ARMGenRegisterInfo.inc"
using namespace llvm;
-static cl::opt<bool>
-ForceAllBaseRegAlloc("arm-force-base-reg-alloc", cl::Hidden, cl::init(false),
- cl::desc("Force use of virtual base registers for stack load/store"));
-static cl::opt<bool>
-EnableLocalStackAlloc("enable-local-stack-alloc", cl::init(true), cl::Hidden,
- cl::desc("Enable pre-regalloc stack frame index allocation"));
-static cl::opt<bool>
-EnableBasePointer("arm-use-base-pointer", cl::Hidden, cl::init(true),
- cl::desc("Enable use of a base pointer for complex stack frames"));
-
-ARMBaseRegisterInfo::ARMBaseRegisterInfo(const ARMBaseInstrInfo &tii,
- const ARMSubtarget &sti)
- : ARMGenRegisterInfo(ARM::LR), TII(tii), STI(sti),
- FramePtr((STI.isTargetDarwin() || STI.isThumb()) ? ARM::R7 : ARM::R11),
- BasePtr(ARM::R6) {
+ARMBaseRegisterInfo::ARMBaseRegisterInfo()
+ : ARMGenRegisterInfo(ARM::LR, 0, 0, ARM::PC), BasePtr(ARM::R6) {}
+
+static unsigned getFramePointerReg(const ARMSubtarget &STI) {
+ if (STI.isTargetMachO()) {
+ if (STI.isTargetDarwin() || STI.isThumb1Only())
+ return ARM::R7;
+ else
+ return ARM::R11;
+ } else if (STI.isTargetWindows())
+ return ARM::R11;
+ else // ARM EABI
+ return STI.isThumb() ? ARM::R7 : ARM::R11;
}
-const unsigned*
+const MCPhysReg*
ARMBaseRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
- static const unsigned CalleeSavedRegs[] = {
- ARM::LR, ARM::R11, ARM::R10, ARM::R9, ARM::R8,
- ARM::R7, ARM::R6, ARM::R5, ARM::R4,
-
- ARM::D15, ARM::D14, ARM::D13, ARM::D12,
- ARM::D11, ARM::D10, ARM::D9, ARM::D8,
- 0
- };
-
- static const unsigned DarwinCalleeSavedRegs[] = {
- // Darwin ABI deviates from ARM standard ABI. R9 is not a callee-saved
- // register.
- ARM::LR, ARM::R7, ARM::R6, ARM::R5, ARM::R4,
- ARM::R11, ARM::R10, ARM::R8,
-
- ARM::D15, ARM::D14, ARM::D13, ARM::D12,
- ARM::D11, ARM::D10, ARM::D9, ARM::D8,
- 0
- };
- return STI.isTargetDarwin() ? DarwinCalleeSavedRegs : CalleeSavedRegs;
+ const ARMSubtarget &STI = MF->getSubtarget<ARMSubtarget>();
+ const MCPhysReg *RegList =
+ STI.isTargetDarwin() ? CSR_iOS_SaveList : CSR_AAPCS_SaveList;
+
+ const Function *F = MF->getFunction();
+ if (F->getCallingConv() == CallingConv::GHC) {
+ // GHC set of callee saved regs is empty as all those regs are
+ // used for passing STG regs around
+ return CSR_NoRegs_SaveList;
+ } else if (F->hasFnAttribute("interrupt")) {
+ if (STI.isMClass()) {
+ // M-class CPUs have hardware which saves the registers needed to allow a
+ // function conforming to the AAPCS to function as a handler.
+ return CSR_AAPCS_SaveList;
+ } else if (F->getFnAttribute("interrupt").getValueAsString() == "FIQ") {
+ // Fast interrupt mode gives the handler a private copy of R8-R14, so less
+ // need to be saved to restore user-mode state.
+ return CSR_FIQ_SaveList;
+ } else {
+ // Generally only R13-R14 (i.e. SP, LR) are automatically preserved by
+ // exception handling.
+ return CSR_GenericInt_SaveList;
+ }
+ }
+
+ return RegList;
+}
+
+const uint32_t *
+ARMBaseRegisterInfo::getCallPreservedMask(const MachineFunction &MF,
+ CallingConv::ID CC) const {
+ const ARMSubtarget &STI = MF.getSubtarget<ARMSubtarget>();
+ if (CC == CallingConv::GHC)
+ // This is academic becase all GHC calls are (supposed to be) tail calls
+ return CSR_NoRegs_RegMask;
+ return STI.isTargetDarwin() ? CSR_iOS_RegMask : CSR_AAPCS_RegMask;
+}
+
+const uint32_t*
+ARMBaseRegisterInfo::getNoPreservedMask() const {
+ return CSR_NoRegs_RegMask;
+}
+
+const uint32_t *
+ARMBaseRegisterInfo::getThisReturnPreservedMask(const MachineFunction &MF,
+ CallingConv::ID CC) const {
+ const ARMSubtarget &STI = MF.getSubtarget<ARMSubtarget>();
+ // This should return a register mask that is the same as that returned by
+ // getCallPreservedMask but that additionally preserves the register used for
+ // the first i32 argument (which must also be the register used to return a
+ // single i32 return value)
+ //
+ // In case that the calling convention does not use the same register for
+ // both or otherwise does not want to enable this optimization, the function
+ // should return NULL
+ if (CC == CallingConv::GHC)
+ // This is academic becase all GHC calls are (supposed to be) tail calls
+ return nullptr;
+ return STI.isTargetDarwin() ? CSR_iOS_ThisReturn_RegMask
+ : CSR_AAPCS_ThisReturn_RegMask;
}
BitVector ARMBaseRegisterInfo::
getReservedRegs(const MachineFunction &MF) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
+ const ARMSubtarget &STI = MF.getSubtarget<ARMSubtarget>();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
// FIXME: avoid re-calculating this every time.
BitVector Reserved(getNumRegs());
Reserved.set(ARM::SP);
Reserved.set(ARM::PC);
Reserved.set(ARM::FPSCR);
+ Reserved.set(ARM::APSR_NZCV);
if (TFI->hasFP(MF))
- Reserved.set(FramePtr);
+ Reserved.set(getFramePointerReg(STI));
if (hasBasePointer(MF))
Reserved.set(BasePtr);
// Some targets reserve R9.
for (unsigned i = 0; i != 16; ++i)
Reserved.set(ARM::D16 + i);
}
- return Reserved;
-}
+ const TargetRegisterClass *RC = &ARM::GPRPairRegClass;
+ for(TargetRegisterClass::iterator I = RC->begin(), E = RC->end(); I!=E; ++I)
+ for (MCSubRegIterator SI(*I, this); SI.isValid(); ++SI)
+ if (Reserved.test(*SI)) Reserved.set(*I);
-bool ARMBaseRegisterInfo::isReservedReg(const MachineFunction &MF,
- unsigned Reg) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
-
- switch (Reg) {
- default: break;
- case ARM::SP:
- case ARM::PC:
- return true;
- case ARM::R6:
- if (hasBasePointer(MF))
- return true;
- break;
- case ARM::R7:
- case ARM::R11:
- if (FramePtr == Reg && TFI->hasFP(MF))
- return true;
- break;
- case ARM::R9:
- return STI.isR9Reserved();
- }
-
- return false;
+ return Reserved;
}
const TargetRegisterClass *
-ARMBaseRegisterInfo::getMatchingSuperRegClass(const TargetRegisterClass *A,
- const TargetRegisterClass *B,
- unsigned SubIdx) const {
- switch (SubIdx) {
- default: return 0;
- case ARM::ssub_0:
- case ARM::ssub_1:
- case ARM::ssub_2:
- case ARM::ssub_3: {
- // S sub-registers.
- if (A->getSize() == 8) {
- if (B == &ARM::SPR_8RegClass)
- return &ARM::DPR_8RegClass;
- assert(B == &ARM::SPRRegClass && "Expecting SPR register class!");
- if (A == &ARM::DPR_8RegClass)
- return A;
- return &ARM::DPR_VFP2RegClass;
- }
-
- if (A->getSize() == 16) {
- if (B == &ARM::SPR_8RegClass)
- return &ARM::QPR_8RegClass;
- return &ARM::QPR_VFP2RegClass;
- }
-
- if (A->getSize() == 32) {
- if (B == &ARM::SPR_8RegClass)
- return 0; // Do not allow coalescing!
- return &ARM::QQPR_VFP2RegClass;
- }
-
- assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
- return 0; // Do not allow coalescing!
- }
- case ARM::dsub_0:
- case ARM::dsub_1:
- case ARM::dsub_2:
- case ARM::dsub_3: {
- // D sub-registers.
- if (A->getSize() == 16) {
- if (B == &ARM::DPR_VFP2RegClass)
- return &ARM::QPR_VFP2RegClass;
- if (B == &ARM::DPR_8RegClass)
- return 0; // Do not allow coalescing!
- return A;
- }
-
- if (A->getSize() == 32) {
- if (B == &ARM::DPR_VFP2RegClass)
- return &ARM::QQPR_VFP2RegClass;
- if (B == &ARM::DPR_8RegClass)
- return 0; // Do not allow coalescing!
- return A;
- }
-
- assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
- if (B != &ARM::DPRRegClass)
- return 0; // Do not allow coalescing!
- return A;
- }
- case ARM::dsub_4:
- case ARM::dsub_5:
- case ARM::dsub_6:
- case ARM::dsub_7: {
- // D sub-registers of QQQQ registers.
- if (A->getSize() == 64 && B == &ARM::DPRRegClass)
- return A;
- return 0; // Do not allow coalescing!
- }
-
- case ARM::qsub_0:
- case ARM::qsub_1: {
- // Q sub-registers.
- if (A->getSize() == 32) {
- if (B == &ARM::QPR_VFP2RegClass)
- return &ARM::QQPR_VFP2RegClass;
- if (B == &ARM::QPR_8RegClass)
- return 0; // Do not allow coalescing!
- return A;
- }
-
- assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
- if (B == &ARM::QPRRegClass)
- return A;
- return 0; // Do not allow coalescing!
- }
- case ARM::qsub_2:
- case ARM::qsub_3: {
- // Q sub-registers of QQQQ registers.
- if (A->getSize() == 64 && B == &ARM::QPRRegClass)
- return A;
- return 0; // Do not allow coalescing!
- }
- }
- return 0;
-}
-
-bool
-ARMBaseRegisterInfo::canCombineSubRegIndices(const TargetRegisterClass *RC,
- SmallVectorImpl<unsigned> &SubIndices,
- unsigned &NewSubIdx) const {
-
- unsigned Size = RC->getSize() * 8;
- if (Size < 6)
- return 0;
-
- NewSubIdx = 0; // Whole register.
- unsigned NumRegs = SubIndices.size();
- if (NumRegs == 8) {
- // 8 D registers -> 1 QQQQ register.
- return (Size == 512 &&
- SubIndices[0] == ARM::dsub_0 &&
- SubIndices[1] == ARM::dsub_1 &&
- SubIndices[2] == ARM::dsub_2 &&
- SubIndices[3] == ARM::dsub_3 &&
- SubIndices[4] == ARM::dsub_4 &&
- SubIndices[5] == ARM::dsub_5 &&
- SubIndices[6] == ARM::dsub_6 &&
- SubIndices[7] == ARM::dsub_7);
- } else if (NumRegs == 4) {
- if (SubIndices[0] == ARM::qsub_0) {
- // 4 Q registers -> 1 QQQQ register.
- return (Size == 512 &&
- SubIndices[1] == ARM::qsub_1 &&
- SubIndices[2] == ARM::qsub_2 &&
- SubIndices[3] == ARM::qsub_3);
- } else if (SubIndices[0] == ARM::dsub_0) {
- // 4 D registers -> 1 QQ register.
- if (Size >= 256 &&
- SubIndices[1] == ARM::dsub_1 &&
- SubIndices[2] == ARM::dsub_2 &&
- SubIndices[3] == ARM::dsub_3) {
- if (Size == 512)
- NewSubIdx = ARM::qqsub_0;
- return true;
- }
- } else if (SubIndices[0] == ARM::dsub_4) {
- // 4 D registers -> 1 QQ register (2nd).
- if (Size == 512 &&
- SubIndices[1] == ARM::dsub_5 &&
- SubIndices[2] == ARM::dsub_6 &&
- SubIndices[3] == ARM::dsub_7) {
- NewSubIdx = ARM::qqsub_1;
- return true;
- }
- } else if (SubIndices[0] == ARM::ssub_0) {
- // 4 S registers -> 1 Q register.
- if (Size >= 128 &&
- SubIndices[1] == ARM::ssub_1 &&
- SubIndices[2] == ARM::ssub_2 &&
- SubIndices[3] == ARM::ssub_3) {
- if (Size >= 256)
- NewSubIdx = ARM::qsub_0;
- return true;
- }
- }
- } else if (NumRegs == 2) {
- if (SubIndices[0] == ARM::qsub_0) {
- // 2 Q registers -> 1 QQ register.
- if (Size >= 256 && SubIndices[1] == ARM::qsub_1) {
- if (Size == 512)
- NewSubIdx = ARM::qqsub_0;
- return true;
- }
- } else if (SubIndices[0] == ARM::qsub_2) {
- // 2 Q registers -> 1 QQ register (2nd).
- if (Size == 512 && SubIndices[1] == ARM::qsub_3) {
- NewSubIdx = ARM::qqsub_1;
- return true;
- }
- } else if (SubIndices[0] == ARM::dsub_0) {
- // 2 D registers -> 1 Q register.
- if (Size >= 128 && SubIndices[1] == ARM::dsub_1) {
- if (Size >= 256)
- NewSubIdx = ARM::qsub_0;
- return true;
- }
- } else if (SubIndices[0] == ARM::dsub_2) {
- // 2 D registers -> 1 Q register (2nd).
- if (Size >= 256 && SubIndices[1] == ARM::dsub_3) {
- NewSubIdx = ARM::qsub_1;
- return true;
- }
- } else if (SubIndices[0] == ARM::dsub_4) {
- // 2 D registers -> 1 Q register (3rd).
- if (Size == 512 && SubIndices[1] == ARM::dsub_5) {
- NewSubIdx = ARM::qsub_2;
- return true;
- }
- } else if (SubIndices[0] == ARM::dsub_6) {
- // 2 D registers -> 1 Q register (3rd).
- if (Size == 512 && SubIndices[1] == ARM::dsub_7) {
- NewSubIdx = ARM::qsub_3;
- return true;
- }
- } else if (SubIndices[0] == ARM::ssub_0) {
- // 2 S registers -> 1 D register.
- if (SubIndices[1] == ARM::ssub_1) {
- if (Size >= 128)
- NewSubIdx = ARM::dsub_0;
- return true;
- }
- } else if (SubIndices[0] == ARM::ssub_2) {
- // 2 S registers -> 1 D register (2nd).
- if (Size >= 128 && SubIndices[1] == ARM::ssub_3) {
- NewSubIdx = ARM::dsub_1;
- return true;
- }
- }
- }
- return false;
-}
-
-const TargetRegisterClass*
-ARMBaseRegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC)
- const {
+ARMBaseRegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC,
+ const MachineFunction &) const {
const TargetRegisterClass *Super = RC;
TargetRegisterClass::sc_iterator I = RC->getSuperClasses();
do {
case ARM::QPRRegClassID:
case ARM::QQPRRegClassID:
case ARM::QQQQPRRegClassID:
+ case ARM::GPRPairRegClassID:
return Super;
}
Super = *I++;
}
const TargetRegisterClass *
-ARMBaseRegisterInfo::getPointerRegClass(unsigned Kind) const {
- return ARM::GPRRegisterClass;
+ARMBaseRegisterInfo::getPointerRegClass(const MachineFunction &MF, unsigned Kind)
+ const {
+ return &ARM::GPRRegClass;
}
const TargetRegisterClass *
ARMBaseRegisterInfo::getCrossCopyRegClass(const TargetRegisterClass *RC) const {
if (RC == &ARM::CCRRegClass)
- return 0; // Can't copy CCR registers.
+ return &ARM::rGPRRegClass; // Can't copy CCR registers.
return RC;
}
unsigned
ARMBaseRegisterInfo::getRegPressureLimit(const TargetRegisterClass *RC,
MachineFunction &MF) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
+ const ARMSubtarget &STI = MF.getSubtarget<ARMSubtarget>();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
switch (RC->getID()) {
default:
}
}
-/// getRawAllocationOrder - Returns the register allocation order for a
-/// specified register class with a target-dependent hint.
-ArrayRef<unsigned>
-ARMBaseRegisterInfo::getRawAllocationOrder(const TargetRegisterClass *RC,
- unsigned HintType, unsigned HintReg,
- const MachineFunction &MF) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
- // Alternative register allocation orders when favoring even / odd registers
- // of register pairs.
-
- // No FP, R9 is available.
- static const unsigned GPREven1[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R6, ARM::R8, ARM::R10,
- ARM::R1, ARM::R3, ARM::R12,ARM::LR, ARM::R5, ARM::R7,
- ARM::R9, ARM::R11
- };
- static const unsigned GPROdd1[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R7, ARM::R9, ARM::R11,
- ARM::R0, ARM::R2, ARM::R12,ARM::LR, ARM::R4, ARM::R6,
- ARM::R8, ARM::R10
- };
-
- // FP is R7, R9 is available.
- static const unsigned GPREven2[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R8, ARM::R10,
- ARM::R1, ARM::R3, ARM::R12,ARM::LR, ARM::R5, ARM::R6,
- ARM::R9, ARM::R11
- };
- static const unsigned GPROdd2[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R9, ARM::R11,
- ARM::R0, ARM::R2, ARM::R12,ARM::LR, ARM::R4, ARM::R6,
- ARM::R8, ARM::R10
- };
-
- // FP is R11, R9 is available.
- static const unsigned GPREven3[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R6, ARM::R8,
- ARM::R1, ARM::R3, ARM::R10,ARM::R12,ARM::LR, ARM::R5, ARM::R7,
- ARM::R9
- };
- static const unsigned GPROdd3[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R6, ARM::R9,
- ARM::R0, ARM::R2, ARM::R10,ARM::R12,ARM::LR, ARM::R4, ARM::R7,
- ARM::R8
- };
-
- // No FP, R9 is not available.
- static const unsigned GPREven4[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R6, ARM::R10,
- ARM::R1, ARM::R3, ARM::R12,ARM::LR, ARM::R5, ARM::R7, ARM::R8,
- ARM::R11
- };
- static const unsigned GPROdd4[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R7, ARM::R11,
- ARM::R0, ARM::R2, ARM::R12,ARM::LR, ARM::R4, ARM::R6, ARM::R8,
- ARM::R10
- };
-
- // FP is R7, R9 is not available.
- static const unsigned GPREven5[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R10,
- ARM::R1, ARM::R3, ARM::R12,ARM::LR, ARM::R5, ARM::R6, ARM::R8,
- ARM::R11
- };
- static const unsigned GPROdd5[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R11,
- ARM::R0, ARM::R2, ARM::R12,ARM::LR, ARM::R4, ARM::R6, ARM::R8,
- ARM::R10
- };
-
- // FP is R11, R9 is not available.
- static const unsigned GPREven6[] = {
- ARM::R0, ARM::R2, ARM::R4, ARM::R6,
- ARM::R1, ARM::R3, ARM::R10,ARM::R12,ARM::LR, ARM::R5, ARM::R7, ARM::R8
- };
- static const unsigned GPROdd6[] = {
- ARM::R1, ARM::R3, ARM::R5, ARM::R7,
- ARM::R0, ARM::R2, ARM::R10,ARM::R12,ARM::LR, ARM::R4, ARM::R6, ARM::R8
- };
-
- // We only support even/odd hints for GPR and rGPR.
- if (RC != ARM::GPRRegisterClass && RC != ARM::rGPRRegisterClass)
- return RC->getRawAllocationOrder(MF);
-
- if (HintType == ARMRI::RegPairEven) {
- if (isPhysicalRegister(HintReg) && getRegisterPairEven(HintReg, MF) == 0)
- // It's no longer possible to fulfill this hint. Return the default
- // allocation order.
- return RC->getRawAllocationOrder(MF);
-
- if (!TFI->hasFP(MF)) {
- if (!STI.isR9Reserved())
- return makeArrayRef(GPREven1);
- else
- return makeArrayRef(GPREven4);
- } else if (FramePtr == ARM::R7) {
- if (!STI.isR9Reserved())
- return makeArrayRef(GPREven2);
- else
- return makeArrayRef(GPREven5);
- } else { // FramePtr == ARM::R11
- if (!STI.isR9Reserved())
- return makeArrayRef(GPREven3);
- else
- return makeArrayRef(GPREven6);
- }
- } else if (HintType == ARMRI::RegPairOdd) {
- if (isPhysicalRegister(HintReg) && getRegisterPairOdd(HintReg, MF) == 0)
- // It's no longer possible to fulfill this hint. Return the default
- // allocation order.
- return RC->getRawAllocationOrder(MF);
-
- if (!TFI->hasFP(MF)) {
- if (!STI.isR9Reserved())
- return makeArrayRef(GPROdd1);
- else
- return makeArrayRef(GPROdd4);
- } else if (FramePtr == ARM::R7) {
- if (!STI.isR9Reserved())
- return makeArrayRef(GPROdd2);
- else
- return makeArrayRef(GPROdd5);
- } else { // FramePtr == ARM::R11
- if (!STI.isR9Reserved())
- return makeArrayRef(GPROdd3);
- else
- return makeArrayRef(GPROdd6);
- }
- }
- return RC->getRawAllocationOrder(MF);
+// Get the other register in a GPRPair.
+static unsigned getPairedGPR(unsigned Reg, bool Odd, const MCRegisterInfo *RI) {
+ for (MCSuperRegIterator Supers(Reg, RI); Supers.isValid(); ++Supers)
+ if (ARM::GPRPairRegClass.contains(*Supers))
+ return RI->getSubReg(*Supers, Odd ? ARM::gsub_1 : ARM::gsub_0);
+ return 0;
}
-/// ResolveRegAllocHint - Resolves the specified register allocation hint
-/// to a physical register. Returns the physical register if it is successful.
-unsigned
-ARMBaseRegisterInfo::ResolveRegAllocHint(unsigned Type, unsigned Reg,
- const MachineFunction &MF) const {
- if (Reg == 0 || !isPhysicalRegister(Reg))
- return 0;
- if (Type == 0)
- return Reg;
- else if (Type == (unsigned)ARMRI::RegPairOdd)
- // Odd register.
- return getRegisterPairOdd(Reg, MF);
- else if (Type == (unsigned)ARMRI::RegPairEven)
- // Even register.
- return getRegisterPairEven(Reg, MF);
- return 0;
+// Resolve the RegPairEven / RegPairOdd register allocator hints.
+void
+ARMBaseRegisterInfo::getRegAllocationHints(unsigned VirtReg,
+ ArrayRef<MCPhysReg> Order,
+ SmallVectorImpl<MCPhysReg> &Hints,
+ const MachineFunction &MF,
+ const VirtRegMap *VRM,
+ const LiveRegMatrix *Matrix) const {
+ const MachineRegisterInfo &MRI = MF.getRegInfo();
+ std::pair<unsigned, unsigned> Hint = MRI.getRegAllocationHint(VirtReg);
+
+ unsigned Odd;
+ switch (Hint.first) {
+ case ARMRI::RegPairEven:
+ Odd = 0;
+ break;
+ case ARMRI::RegPairOdd:
+ Odd = 1;
+ break;
+ default:
+ TargetRegisterInfo::getRegAllocationHints(VirtReg, Order, Hints, MF, VRM);
+ return;
+ }
+
+ // This register should preferably be even (Odd == 0) or odd (Odd == 1).
+ // Check if the other part of the pair has already been assigned, and provide
+ // the paired register as the first hint.
+ unsigned Paired = Hint.second;
+ if (Paired == 0)
+ return;
+
+ unsigned PairedPhys = 0;
+ if (TargetRegisterInfo::isPhysicalRegister(Paired)) {
+ PairedPhys = Paired;
+ } else if (VRM && VRM->hasPhys(Paired)) {
+ PairedPhys = getPairedGPR(VRM->getPhys(Paired), Odd, this);
+ }
+
+ // First prefer the paired physreg.
+ if (PairedPhys &&
+ std::find(Order.begin(), Order.end(), PairedPhys) != Order.end())
+ Hints.push_back(PairedPhys);
+
+ // Then prefer even or odd registers.
+ for (unsigned I = 0, E = Order.size(); I != E; ++I) {
+ unsigned Reg = Order[I];
+ if (Reg == PairedPhys || (getEncodingValue(Reg) & 1) != Odd)
+ continue;
+ // Don't provide hints that are paired to a reserved register.
+ unsigned Paired = getPairedGPR(Reg, !Odd, this);
+ if (!Paired || MRI.isReserved(Paired))
+ continue;
+ Hints.push_back(Reg);
+ }
}
void
-ARMBaseRegisterInfo::UpdateRegAllocHint(unsigned Reg, unsigned NewReg,
+ARMBaseRegisterInfo::updateRegAllocHint(unsigned Reg, unsigned NewReg,
MachineFunction &MF) const {
MachineRegisterInfo *MRI = &MF.getRegInfo();
std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(Reg);
// change.
unsigned OtherReg = Hint.second;
Hint = MRI->getRegAllocationHint(OtherReg);
- if (Hint.second == Reg)
- // Make sure the pair has not already divorced.
+ // Make sure the pair has not already divorced.
+ if (Hint.second == Reg) {
MRI->setRegAllocationHint(OtherReg, Hint.first, NewReg);
- }
-}
-
-bool
-ARMBaseRegisterInfo::avoidWriteAfterWrite(const TargetRegisterClass *RC) const {
- // CortexA9 has a Write-after-write hazard for NEON registers.
- if (!STI.isCortexA9())
- return false;
-
- switch (RC->getID()) {
- case ARM::DPRRegClassID:
- case ARM::DPR_8RegClassID:
- case ARM::DPR_VFP2RegClassID:
- case ARM::QPRRegClassID:
- case ARM::QPR_8RegClassID:
- case ARM::QPR_VFP2RegClassID:
- case ARM::SPRRegClassID:
- case ARM::SPR_8RegClassID:
- // Avoid reusing S, D, and Q registers.
- // Don't increase register pressure for QQ and QQQQ.
- return true;
- default:
- return false;
+ if (TargetRegisterInfo::isVirtualRegister(NewReg))
+ MRI->setRegAllocationHint(NewReg,
+ Hint.first == (unsigned)ARMRI::RegPairOdd ? ARMRI::RegPairEven
+ : ARMRI::RegPairOdd, OtherReg);
+ }
}
}
bool ARMBaseRegisterInfo::hasBasePointer(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
- if (!EnableBasePointer)
- return false;
-
- if (needsStackRealignment(MF) && MFI->hasVarSizedObjects())
+ // When outgoing call frames are so large that we adjust the stack pointer
+ // around the call, we can no longer use the stack pointer to reach the
+ // emergency spill slot.
+ if (needsStackRealignment(MF) && !TFI->hasReservedCallFrame(MF))
return true;
// Thumb has trouble with negative offsets from the FP. Thumb2 has a limited
}
bool ARMBaseRegisterInfo::canRealignStack(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const MachineRegisterInfo *MRI = &MF.getRegInfo();
const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
// We can't realign the stack if:
// 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.
- return (MF.getTarget().Options.RealignStack && !AFI->isThumb1OnlyFunction() &&
- (!MFI->hasVarSizedObjects() || EnableBasePointer));
-}
-
-bool ARMBaseRegisterInfo::
-needsStackRealignment(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- const Function *F = MF.getFunction();
- unsigned StackAlign = MF.getTarget().getFrameLowering()->getStackAlignment();
- bool requiresRealignment = ((MFI->getLocalFrameMaxAlign() > StackAlign) ||
- F->hasFnAttr(Attribute::StackAlignment));
-
- return requiresRealignment && canRealignStack(MF);
+ if (!TargetRegisterInfo::canRealignStack(MF))
+ return false;
+ if (AFI->isThumb1OnlyFunction())
+ return false;
+ // Stack realignment requires a frame pointer. If we already started
+ // register allocation with frame pointer elimination, it is too late now.
+ if (!MRI->canReserveReg(getFramePointerReg(MF.getSubtarget<ARMSubtarget>())))
+ return false;
+ // We may also need a base pointer if there are dynamic allocas or stack
+ // pointer adjustments around calls.
+ if (TFI->hasReservedCallFrame(MF))
+ return true;
+ // A base pointer is required and allowed. Check that it isn't too late to
+ // reserve it.
+ return MRI->canReserveReg(BasePtr);
}
bool ARMBaseRegisterInfo::
unsigned
ARMBaseRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
+ const ARMSubtarget &STI = MF.getSubtarget<ARMSubtarget>();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
if (TFI->hasFP(MF))
- return FramePtr;
+ return getFramePointerReg(STI);
return ARM::SP;
}
-unsigned ARMBaseRegisterInfo::getEHExceptionRegister() const {
- llvm_unreachable("What is the exception register");
- return 0;
-}
-
-unsigned ARMBaseRegisterInfo::getEHHandlerRegister() const {
- llvm_unreachable("What is the exception handler register");
- return 0;
-}
-
-unsigned ARMBaseRegisterInfo::getRegisterPairEven(unsigned Reg,
- const MachineFunction &MF) const {
- switch (Reg) {
- default: break;
- // Return 0 if either register of the pair is a special register.
- // So no R12, etc.
- case ARM::R1: return ARM::R0;
- case ARM::R3: return ARM::R2;
- case ARM::R5: return ARM::R4;
- case ARM::R7:
- return (isReservedReg(MF, ARM::R7) || isReservedReg(MF, ARM::R6))
- ? 0 : ARM::R6;
- case ARM::R9: return isReservedReg(MF, ARM::R9) ? 0 :ARM::R8;
- case ARM::R11: return isReservedReg(MF, ARM::R11) ? 0 : ARM::R10;
-
- case ARM::S1: return ARM::S0;
- case ARM::S3: return ARM::S2;
- case ARM::S5: return ARM::S4;
- case ARM::S7: return ARM::S6;
- case ARM::S9: return ARM::S8;
- case ARM::S11: return ARM::S10;
- case ARM::S13: return ARM::S12;
- case ARM::S15: return ARM::S14;
- case ARM::S17: return ARM::S16;
- case ARM::S19: return ARM::S18;
- case ARM::S21: return ARM::S20;
- case ARM::S23: return ARM::S22;
- case ARM::S25: return ARM::S24;
- case ARM::S27: return ARM::S26;
- case ARM::S29: return ARM::S28;
- case ARM::S31: return ARM::S30;
-
- case ARM::D1: return ARM::D0;
- case ARM::D3: return ARM::D2;
- case ARM::D5: return ARM::D4;
- case ARM::D7: return ARM::D6;
- case ARM::D9: return ARM::D8;
- case ARM::D11: return ARM::D10;
- case ARM::D13: return ARM::D12;
- case ARM::D15: return ARM::D14;
- case ARM::D17: return ARM::D16;
- case ARM::D19: return ARM::D18;
- case ARM::D21: return ARM::D20;
- case ARM::D23: return ARM::D22;
- case ARM::D25: return ARM::D24;
- case ARM::D27: return ARM::D26;
- case ARM::D29: return ARM::D28;
- case ARM::D31: return ARM::D30;
- }
-
- return 0;
-}
-
-unsigned ARMBaseRegisterInfo::getRegisterPairOdd(unsigned Reg,
- const MachineFunction &MF) const {
- switch (Reg) {
- default: break;
- // Return 0 if either register of the pair is a special register.
- // So no R12, etc.
- case ARM::R0: return ARM::R1;
- case ARM::R2: return ARM::R3;
- case ARM::R4: return ARM::R5;
- case ARM::R6:
- return (isReservedReg(MF, ARM::R7) || isReservedReg(MF, ARM::R6))
- ? 0 : ARM::R7;
- case ARM::R8: return isReservedReg(MF, ARM::R9) ? 0 :ARM::R9;
- case ARM::R10: return isReservedReg(MF, ARM::R11) ? 0 : ARM::R11;
-
- case ARM::S0: return ARM::S1;
- case ARM::S2: return ARM::S3;
- case ARM::S4: return ARM::S5;
- case ARM::S6: return ARM::S7;
- case ARM::S8: return ARM::S9;
- case ARM::S10: return ARM::S11;
- case ARM::S12: return ARM::S13;
- case ARM::S14: return ARM::S15;
- case ARM::S16: return ARM::S17;
- case ARM::S18: return ARM::S19;
- case ARM::S20: return ARM::S21;
- case ARM::S22: return ARM::S23;
- case ARM::S24: return ARM::S25;
- case ARM::S26: return ARM::S27;
- case ARM::S28: return ARM::S29;
- case ARM::S30: return ARM::S31;
-
- case ARM::D0: return ARM::D1;
- case ARM::D2: return ARM::D3;
- case ARM::D4: return ARM::D5;
- case ARM::D6: return ARM::D7;
- case ARM::D8: return ARM::D9;
- case ARM::D10: return ARM::D11;
- case ARM::D12: return ARM::D13;
- case ARM::D14: return ARM::D15;
- case ARM::D16: return ARM::D17;
- case ARM::D18: return ARM::D19;
- case ARM::D20: return ARM::D21;
- case ARM::D22: return ARM::D23;
- case ARM::D24: return ARM::D25;
- case ARM::D26: return ARM::D27;
- case ARM::D28: return ARM::D29;
- case ARM::D30: return ARM::D31;
- }
-
- return 0;
-}
-
/// emitLoadConstPool - Emits a load from constpool to materialize the
/// specified immediate.
void ARMBaseRegisterInfo::
ARMCC::CondCodes Pred,
unsigned PredReg, unsigned MIFlags) const {
MachineFunction &MF = *MBB.getParent();
+ const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
MachineConstantPool *ConstantPool = MF.getConstantPool();
const Constant *C =
ConstantInt::get(Type::getInt32Ty(MF.getFunction()->getContext()), Val);
}
bool ARMBaseRegisterInfo::
-requiresFrameIndexScavenging(const MachineFunction &MF) const {
+trackLivenessAfterRegAlloc(const MachineFunction &MF) const {
return true;
}
bool ARMBaseRegisterInfo::
-requiresVirtualBaseRegisters(const MachineFunction &MF) const {
- return EnableLocalStackAlloc;
-}
-
-static void
-emitSPUpdate(bool isARM,
- MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
- DebugLoc dl, const ARMBaseInstrInfo &TII,
- int NumBytes,
- ARMCC::CondCodes Pred = ARMCC::AL, unsigned PredReg = 0) {
- if (isARM)
- emitARMRegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes,
- Pred, PredReg, TII);
- else
- emitT2RegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes,
- Pred, PredReg, TII);
+requiresFrameIndexScavenging(const MachineFunction &MF) const {
+ return true;
}
-
-void ARMBaseRegisterInfo::
-eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
- MachineBasicBlock::iterator I) const {
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
- if (!TFI->hasReservedCallFrame(MF)) {
- // If we have alloca, convert as follows:
- // ADJCALLSTACKDOWN -> sub, sp, sp, amount
- // ADJCALLSTACKUP -> add, sp, sp, amount
- MachineInstr *Old = I;
- DebugLoc dl = Old->getDebugLoc();
- unsigned Amount = Old->getOperand(0).getImm();
- if (Amount != 0) {
- // We need to keep the stack aligned properly. To do this, we round the
- // amount of space needed for the outgoing arguments up to the next
- // alignment boundary.
- unsigned Align = TFI->getStackAlignment();
- Amount = (Amount+Align-1)/Align*Align;
-
- ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- assert(!AFI->isThumb1OnlyFunction() &&
- "This eliminateCallFramePseudoInstr does not support Thumb1!");
- bool isARM = !AFI->isThumbFunction();
-
- // Replace the pseudo instruction with a new instruction...
- unsigned Opc = Old->getOpcode();
- int PIdx = Old->findFirstPredOperandIdx();
- ARMCC::CondCodes Pred = (PIdx == -1)
- ? ARMCC::AL : (ARMCC::CondCodes)Old->getOperand(PIdx).getImm();
- if (Opc == ARM::ADJCALLSTACKDOWN || Opc == ARM::tADJCALLSTACKDOWN) {
- // Note: PredReg is operand 2 for ADJCALLSTACKDOWN.
- unsigned PredReg = Old->getOperand(2).getReg();
- emitSPUpdate(isARM, MBB, I, dl, TII, -Amount, Pred, PredReg);
- } else {
- // Note: PredReg is operand 3 for ADJCALLSTACKUP.
- unsigned PredReg = Old->getOperand(3).getReg();
- assert(Opc == ARM::ADJCALLSTACKUP || Opc == ARM::tADJCALLSTACKUP);
- emitSPUpdate(isARM, MBB, I, dl, TII, Amount, Pred, PredReg);
- }
- }
- }
- MBB.erase(I);
+bool ARMBaseRegisterInfo::
+requiresVirtualBaseRegisters(const MachineFunction &MF) const {
+ return true;
}
int64_t ARMBaseRegisterInfo::
getFrameIndexInstrOffset(const MachineInstr *MI, int Idx) const {
const MCInstrDesc &Desc = MI->getDesc();
unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
- int64_t InstrOffs = 0;;
+ int64_t InstrOffs = 0;
int Scale = 1;
unsigned ImmIdx = 0;
switch (AddrMode) {
}
default:
llvm_unreachable("Unsupported addressing mode!");
- break;
}
return InstrOffs * Scale;
case ARM::VLDRS: case ARM::VLDRD:
case ARM::VSTRS: case ARM::VSTRD:
case ARM::tSTRspi: case ARM::tLDRspi:
- if (ForceAllBaseRegAlloc)
- return true;
break;
default:
return false;
// Note that the incoming offset is based on the SP value at function entry,
// so it'll be negative.
MachineFunction &MF = *MI->getParent()->getParent();
- const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
// The incoming offset is relating to the SP at the start of the function,
// but when we access the local it'll be relative to the SP after local
// allocation, so adjust our SP-relative offset by that allocation size.
- Offset = -Offset;
Offset += MFI->getLocalFrameSize();
// Assume that we'll have at least some spill slots allocated.
// FIXME: This is a total SWAG number. We should run some statistics
// and pick a real one.
Offset += 128; // 128 bytes of spill slots
- // If there is a frame pointer, try using it.
+ // If there's a frame pointer and the addressing mode allows it, try using it.
// The FP is only available if there is no dynamic realignment. We
// don't know for sure yet whether we'll need that, so we guess based
// on whether there are any local variables that would trigger it.
unsigned StackAlign = TFI->getStackAlignment();
- if (TFI->hasFP(MF) &&
+ if (TFI->hasFP(MF) &&
!((MFI->getLocalFrameMaxAlign() > StackAlign) && canRealignStack(MF))) {
- if (isFrameOffsetLegal(MI, FPOffset))
+ if (isFrameOffsetLegal(MI, getFrameRegister(MF), FPOffset))
return false;
}
// If we can reference via the stack pointer, try that.
// to only disallow SP relative references in the live range of
// the VLA(s). In practice, it's unclear how much difference that
// would make, but it may be worth doing.
- if (!MFI->hasVarSizedObjects() && isFrameOffsetLegal(MI, Offset))
+ if (!MFI->hasVarSizedObjects() && isFrameOffsetLegal(MI, ARM::SP, Offset))
return false;
// The offset likely isn't legal, we want to allocate a virtual base register.
int64_t Offset) const {
ARMFunctionInfo *AFI = MBB->getParent()->getInfo<ARMFunctionInfo>();
unsigned ADDriOpc = !AFI->isThumbFunction() ? ARM::ADDri :
- (AFI->isThumb1OnlyFunction() ? ARM::tADDrSPi : ARM::t2ADDri);
+ (AFI->isThumb1OnlyFunction() ? ARM::tADDframe : ARM::t2ADDri);
MachineBasicBlock::iterator Ins = MBB->begin();
DebugLoc DL; // Defaults to "unknown"
if (Ins != MBB->end())
DL = Ins->getDebugLoc();
- const MCInstrDesc &MCID = TII.get(ADDriOpc);
+ const MachineFunction &MF = *MBB->getParent();
MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
- MRI.constrainRegClass(BaseReg, TII.getRegClass(MCID, 0, this));
+ const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
+ const MCInstrDesc &MCID = TII.get(ADDriOpc);
+ MRI.constrainRegClass(BaseReg, TII.getRegClass(MCID, 0, this, MF));
- MachineInstrBuilder MIB = AddDefaultPred(BuildMI(*MBB, Ins, DL, MCID, BaseReg)
- .addFrameIndex(FrameIdx).addImm(Offset));
+ MachineInstrBuilder MIB = BuildMI(*MBB, Ins, DL, MCID, BaseReg)
+ .addFrameIndex(FrameIdx).addImm(Offset);
if (!AFI->isThumb1OnlyFunction())
- AddDefaultCC(MIB);
+ AddDefaultCC(AddDefaultPred(MIB));
}
-void
-ARMBaseRegisterInfo::resolveFrameIndex(MachineBasicBlock::iterator I,
- unsigned BaseReg, int64_t Offset) const {
- MachineInstr &MI = *I;
+void ARMBaseRegisterInfo::resolveFrameIndex(MachineInstr &MI, unsigned BaseReg,
+ int64_t Offset) const {
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
+ const ARMBaseInstrInfo &TII =
+ *static_cast<const ARMBaseInstrInfo *>(MF.getSubtarget().getInstrInfo());
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
int Off = Offset; // ARM doesn't need the general 64-bit offsets
unsigned i = 0;
(void)Done;
}
-bool ARMBaseRegisterInfo::isFrameOffsetLegal(const MachineInstr *MI,
+bool ARMBaseRegisterInfo::isFrameOffsetLegal(const MachineInstr *MI, unsigned BaseReg,
int64_t Offset) const {
const MCInstrDesc &Desc = MI->getDesc();
unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
NumBits = 8;
break;
case ARMII::AddrModeT1_s:
- NumBits = 5;
+ NumBits = (BaseReg == ARM::SP ? 8 : 5);
Scale = 4;
isSigned = false;
break;
default:
llvm_unreachable("Unsupported addressing mode!");
- break;
}
Offset += getFrameIndexInstrOffset(MI, i);
void
ARMBaseRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
- int SPAdj, RegScavenger *RS) const {
- unsigned i = 0;
+ int SPAdj, unsigned FIOperandNum,
+ RegScavenger *RS) const {
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
- const ARMFrameLowering *TFI =
- static_cast<const ARMFrameLowering*>(MF.getTarget().getFrameLowering());
+ const ARMBaseInstrInfo &TII =
+ *static_cast<const ARMBaseInstrInfo *>(MF.getSubtarget().getInstrInfo());
+ const ARMFrameLowering *TFI = getFrameLowering(MF);
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
"This eliminateFrameIndex does not support Thumb1!");
-
- while (!MI.getOperand(i).isFI()) {
- ++i;
- assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
- }
-
- int FrameIndex = MI.getOperand(i).getIndex();
+ int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
unsigned FrameReg;
int Offset = TFI->ResolveFrameIndexReference(MF, FrameIndex, FrameReg, SPAdj);
- // Special handling of dbg_value instructions.
- if (MI.isDebugValue()) {
- MI.getOperand(i). ChangeToRegister(FrameReg, false /*isDef*/);
- MI.getOperand(i+1).ChangeToImmediate(Offset);
- return;
+ // PEI::scavengeFrameVirtualRegs() cannot accurately track SPAdj because the
+ // call frame setup/destroy instructions have already been eliminated. That
+ // means the stack pointer cannot be used to access the emergency spill slot
+ // when !hasReservedCallFrame().
+#ifndef NDEBUG
+ if (RS && FrameReg == ARM::SP && RS->isScavengingFrameIndex(FrameIndex)){
+ assert(TFI->hasReservedCallFrame(MF) &&
+ "Cannot use SP to access the emergency spill slot in "
+ "functions without a reserved call frame");
+ assert(!MF.getFrameInfo()->hasVarSizedObjects() &&
+ "Cannot use SP to access the emergency spill slot in "
+ "functions with variable sized frame objects");
}
+#endif // NDEBUG
+
+ assert(!MI.isDebugValue() && "DBG_VALUEs should be handled in target-independent code");
// Modify MI as necessary to handle as much of 'Offset' as possible
bool Done = false;
if (!AFI->isThumbFunction())
- Done = rewriteARMFrameIndex(MI, i, FrameReg, Offset, TII);
+ Done = rewriteARMFrameIndex(MI, FIOperandNum, FrameReg, Offset, TII);
else {
assert(AFI->isThumb2Function());
- Done = rewriteT2FrameIndex(MI, i, FrameReg, Offset, TII);
+ Done = rewriteT2FrameIndex(MI, FIOperandNum, FrameReg, Offset, TII);
}
if (Done)
return;
unsigned PredReg = (PIdx == -1) ? 0 : MI.getOperand(PIdx+1).getReg();
if (Offset == 0)
// Must be addrmode4/6.
- MI.getOperand(i).ChangeToRegister(FrameReg, false, false, false);
+ MI.getOperand(FIOperandNum).ChangeToRegister(FrameReg, false, false, false);
else {
- ScratchReg = MF.getRegInfo().createVirtualRegister(ARM::GPRRegisterClass);
+ ScratchReg = MF.getRegInfo().createVirtualRegister(&ARM::GPRRegClass);
if (!AFI->isThumbFunction())
emitARMRegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
Offset, Pred, PredReg, TII);
Offset, Pred, PredReg, TII);
}
// Update the original instruction to use the scratch register.
- MI.getOperand(i).ChangeToRegister(ScratchReg, false, false, true);
+ MI.getOperand(FIOperandNum).ChangeToRegister(ScratchReg, false, false,true);
+ }
+}
+
+bool ARMBaseRegisterInfo::shouldCoalesce(MachineInstr *MI,
+ const TargetRegisterClass *SrcRC,
+ unsigned SubReg,
+ const TargetRegisterClass *DstRC,
+ unsigned DstSubReg,
+ const TargetRegisterClass *NewRC) const {
+ auto MBB = MI->getParent();
+ auto MF = MBB->getParent();
+ const MachineRegisterInfo &MRI = MF->getRegInfo();
+ // If not copying into a sub-register this should be ok because we shouldn't
+ // need to split the reg.
+ if (!DstSubReg)
+ return true;
+ // Small registers don't frequently cause a problem, so we can coalesce them.
+ if (NewRC->getSize() < 32 && DstRC->getSize() < 32 && SrcRC->getSize() < 32)
+ return true;
+
+ auto NewRCWeight =
+ MRI.getTargetRegisterInfo()->getRegClassWeight(NewRC);
+ auto SrcRCWeight =
+ MRI.getTargetRegisterInfo()->getRegClassWeight(SrcRC);
+ auto DstRCWeight =
+ MRI.getTargetRegisterInfo()->getRegClassWeight(DstRC);
+ // If the source register class is more expensive than the destination, the
+ // coalescing is probably profitable.
+ if (SrcRCWeight.RegWeight > NewRCWeight.RegWeight)
+ return true;
+ if (DstRCWeight.RegWeight > NewRCWeight.RegWeight)
+ return true;
+
+ // If the register allocator isn't constrained, we can always allow coalescing
+ // unfortunately we don't know yet if we will be constrained.
+ // The goal of this heuristic is to restrict how many expensive registers
+ // we allow to coalesce in a given basic block.
+ auto AFI = MF->getInfo<ARMFunctionInfo>();
+ auto It = AFI->getCoalescedWeight(MBB);
+
+ DEBUG(dbgs() << "\tARM::shouldCoalesce - Coalesced Weight: "
+ << It->second << "\n");
+ DEBUG(dbgs() << "\tARM::shouldCoalesce - Reg Weight: "
+ << NewRCWeight.RegWeight << "\n");
+
+ // This number is the largest round number that which meets the criteria:
+ // (1) addresses PR18825
+ // (2) generates better code in some test cases (like vldm-shed-a9.ll)
+ // (3) Doesn't regress any test cases (in-tree, test-suite, and SPEC)
+ // In practice the SizeMultiplier will only factor in for straight line code
+ // that uses a lot of NEON vectors, which isn't terribly common.
+ unsigned SizeMultiplier = MBB->size()/100;
+ SizeMultiplier = SizeMultiplier ? SizeMultiplier : 1;
+ if (It->second < NewRCWeight.WeightLimit * SizeMultiplier) {
+ It->second += NewRCWeight.RegWeight;
+ return true;
}
+ return false;
}
projects / oota-llvm.git / blobdiff