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-rw-r--r--contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp664
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diff --git a/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp b/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp
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index 000000000000..c5eb14f3e608
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+++ b/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp
@@ -0,0 +1,664 @@
+//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information --------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the Thumb-2 implementation of the TargetInstrInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Thumb2InstrInfo.h"
+#include "ARMMachineFunctionInfo.h"
+#include "MCTargetDesc/ARMAddressingModes.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineMemOperand.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetRegisterInfo.h"
+#include "llvm/IR/DebugLoc.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCInstrDesc.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Target/TargetMachine.h"
+#include <cassert>
+
+using namespace llvm;
+
+static cl::opt<bool>
+OldT2IfCvt("old-thumb2-ifcvt", cl::Hidden,
+ cl::desc("Use old-style Thumb2 if-conversion heuristics"),
+ cl::init(false));
+
+Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
+ : ARMBaseInstrInfo(STI) {}
+
+/// Return the noop instruction to use for a noop.
+void Thumb2InstrInfo::getNoop(MCInst &NopInst) const {
+ NopInst.setOpcode(ARM::tHINT);
+ NopInst.addOperand(MCOperand::createImm(0));
+ NopInst.addOperand(MCOperand::createImm(ARMCC::AL));
+ NopInst.addOperand(MCOperand::createReg(0));
+}
+
+unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {
+ // FIXME
+ return 0;
+}
+
+void
+Thumb2InstrInfo::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
+ MachineBasicBlock *NewDest) const {
+ MachineBasicBlock *MBB = Tail->getParent();
+ ARMFunctionInfo *AFI = MBB->getParent()->getInfo<ARMFunctionInfo>();
+ if (!AFI->hasITBlocks() || Tail->isBranch()) {
+ TargetInstrInfo::ReplaceTailWithBranchTo(Tail, NewDest);
+ return;
+ }
+
+ // If the first instruction of Tail is predicated, we may have to update
+ // the IT instruction.
+ unsigned PredReg = 0;
+ ARMCC::CondCodes CC = getInstrPredicate(*Tail, PredReg);
+ MachineBasicBlock::iterator MBBI = Tail;
+ if (CC != ARMCC::AL)
+ // Expecting at least the t2IT instruction before it.
+ --MBBI;
+
+ // Actually replace the tail.
+ TargetInstrInfo::ReplaceTailWithBranchTo(Tail, NewDest);
+
+ // Fix up IT.
+ if (CC != ARMCC::AL) {
+ MachineBasicBlock::iterator E = MBB->begin();
+ unsigned Count = 4; // At most 4 instructions in an IT block.
+ while (Count && MBBI != E) {
+ if (MBBI->isDebugValue()) {
+ --MBBI;
+ continue;
+ }
+ if (MBBI->getOpcode() == ARM::t2IT) {
+ unsigned Mask = MBBI->getOperand(1).getImm();
+ if (Count == 4)
+ MBBI->eraseFromParent();
+ else {
+ unsigned MaskOn = 1 << Count;
+ unsigned MaskOff = ~(MaskOn - 1);
+ MBBI->getOperand(1).setImm((Mask & MaskOff) | MaskOn);
+ }
+ return;
+ }
+ --MBBI;
+ --Count;
+ }
+
+ // Ctrl flow can reach here if branch folding is run before IT block
+ // formation pass.
+ }
+}
+
+bool
+Thumb2InstrInfo::isLegalToSplitMBBAt(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI) const {
+ while (MBBI->isDebugValue()) {
+ ++MBBI;
+ if (MBBI == MBB.end())
+ return false;
+ }
+
+ unsigned PredReg = 0;
+ return getITInstrPredicate(*MBBI, PredReg) == ARMCC::AL;
+}
+
+void Thumb2InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I,
+ const DebugLoc &DL, unsigned DestReg,
+ unsigned SrcReg, bool KillSrc) const {
+ // Handle SPR, DPR, and QPR copies.
+ if (!ARM::GPRRegClass.contains(DestReg, SrcReg))
+ return ARMBaseInstrInfo::copyPhysReg(MBB, I, DL, DestReg, SrcReg, KillSrc);
+
+ BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg)
+ .addReg(SrcReg, getKillRegState(KillSrc))
+ .add(predOps(ARMCC::AL));
+}
+
+void Thumb2InstrInfo::
+storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+ unsigned SrcReg, bool isKill, int FI,
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ DebugLoc DL;
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ MachineFunction &MF = *MBB.getParent();
+ MachineFrameInfo &MFI = MF.getFrameInfo();
+ MachineMemOperand *MMO = MF.getMachineMemOperand(
+ MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOStore,
+ MFI.getObjectSize(FI), MFI.getObjectAlignment(FI));
+
+ if (RC == &ARM::GPRRegClass || RC == &ARM::tGPRRegClass ||
+ RC == &ARM::tcGPRRegClass || RC == &ARM::rGPRRegClass ||
+ RC == &ARM::GPRnopcRegClass) {
+ BuildMI(MBB, I, DL, get(ARM::t2STRi12))
+ .addReg(SrcReg, getKillRegState(isKill))
+ .addFrameIndex(FI)
+ .addImm(0)
+ .addMemOperand(MMO)
+ .add(predOps(ARMCC::AL));
+ return;
+ }
+
+ if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
+ // Thumb2 STRD expects its dest-registers to be in rGPR. Not a problem for
+ // gsub_0, but needs an extra constraint for gsub_1 (which could be sp
+ // otherwise).
+ if (TargetRegisterInfo::isVirtualRegister(SrcReg)) {
+ MachineRegisterInfo *MRI = &MF.getRegInfo();
+ MRI->constrainRegClass(SrcReg, &ARM::GPRPair_with_gsub_1_in_rGPRRegClass);
+ }
+
+ MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::t2STRDi8));
+ AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI);
+ AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI);
+ MIB.addFrameIndex(FI).addImm(0).addMemOperand(MMO).add(predOps(ARMCC::AL));
+ return;
+ }
+
+ ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI);
+}
+
+void Thumb2InstrInfo::
+loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+ unsigned DestReg, int FI,
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ MachineFunction &MF = *MBB.getParent();
+ MachineFrameInfo &MFI = MF.getFrameInfo();
+ MachineMemOperand *MMO = MF.getMachineMemOperand(
+ MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOLoad,
+ MFI.getObjectSize(FI), MFI.getObjectAlignment(FI));
+ DebugLoc DL;
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ if (RC == &ARM::GPRRegClass || RC == &ARM::tGPRRegClass ||
+ RC == &ARM::tcGPRRegClass || RC == &ARM::rGPRRegClass ||
+ RC == &ARM::GPRnopcRegClass) {
+ BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg)
+ .addFrameIndex(FI)
+ .addImm(0)
+ .addMemOperand(MMO)
+ .add(predOps(ARMCC::AL));
+ return;
+ }
+
+ if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
+ // Thumb2 LDRD expects its dest-registers to be in rGPR. Not a problem for
+ // gsub_0, but needs an extra constraint for gsub_1 (which could be sp
+ // otherwise).
+ if (TargetRegisterInfo::isVirtualRegister(DestReg)) {
+ MachineRegisterInfo *MRI = &MF.getRegInfo();
+ MRI->constrainRegClass(DestReg,
+ &ARM::GPRPair_with_gsub_1_in_rGPRRegClass);
+ }
+
+ MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::t2LDRDi8));
+ AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI);
+ AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI);
+ MIB.addFrameIndex(FI).addImm(0).addMemOperand(MMO).add(predOps(ARMCC::AL));
+
+ if (TargetRegisterInfo::isPhysicalRegister(DestReg))
+ MIB.addReg(DestReg, RegState::ImplicitDefine);
+ return;
+ }
+
+ ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI);
+}
+
+void Thumb2InstrInfo::expandLoadStackGuard(
+ MachineBasicBlock::iterator MI) const {
+ MachineFunction &MF = *MI->getParent()->getParent();
+ if (MF.getTarget().isPositionIndependent())
+ expandLoadStackGuardBase(MI, ARM::t2MOV_ga_pcrel, ARM::t2LDRi12);
+ else
+ expandLoadStackGuardBase(MI, ARM::t2MOVi32imm, ARM::t2LDRi12);
+}
+
+void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ const DebugLoc &dl, unsigned DestReg,
+ unsigned BaseReg, int NumBytes,
+ ARMCC::CondCodes Pred, unsigned PredReg,
+ const ARMBaseInstrInfo &TII,
+ unsigned MIFlags) {
+ if (NumBytes == 0 && DestReg != BaseReg) {
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), DestReg)
+ .addReg(BaseReg, RegState::Kill)
+ .addImm((unsigned)Pred).addReg(PredReg).setMIFlags(MIFlags);
+ return;
+ }
+
+ bool isSub = NumBytes < 0;
+ if (isSub) NumBytes = -NumBytes;
+
+ // If profitable, use a movw or movt to materialize the offset.
+ // FIXME: Use the scavenger to grab a scratch register.
+ if (DestReg != ARM::SP && DestReg != BaseReg &&
+ NumBytes >= 4096 &&
+ ARM_AM::getT2SOImmVal(NumBytes) == -1) {
+ bool Fits = false;
+ if (NumBytes < 65536) {
+ // Use a movw to materialize the 16-bit constant.
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg)
+ .addImm(NumBytes)
+ .addImm((unsigned)Pred).addReg(PredReg).setMIFlags(MIFlags);
+ Fits = true;
+ } else if ((NumBytes & 0xffff) == 0) {
+ // Use a movt to materialize the 32-bit constant.
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg)
+ .addReg(DestReg)
+ .addImm(NumBytes >> 16)
+ .addImm((unsigned)Pred).addReg(PredReg).setMIFlags(MIFlags);
+ Fits = true;
+ }
+
+ if (Fits) {
+ if (isSub) {
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::t2SUBrr), DestReg)
+ .addReg(BaseReg)
+ .addReg(DestReg, RegState::Kill)
+ .add(predOps(Pred, PredReg))
+ .add(condCodeOp())
+ .setMIFlags(MIFlags);
+ } else {
+ // Here we know that DestReg is not SP but we do not
+ // know anything about BaseReg. t2ADDrr is an invalid
+ // instruction is SP is used as the second argument, but
+ // is fine if SP is the first argument. To be sure we
+ // do not generate invalid encoding, put BaseReg first.
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::t2ADDrr), DestReg)
+ .addReg(BaseReg)
+ .addReg(DestReg, RegState::Kill)
+ .add(predOps(Pred, PredReg))
+ .add(condCodeOp())
+ .setMIFlags(MIFlags);
+ }
+ return;
+ }
+ }
+
+ while (NumBytes) {
+ unsigned ThisVal = NumBytes;
+ unsigned Opc = 0;
+ if (DestReg == ARM::SP && BaseReg != ARM::SP) {
+ // mov sp, rn. Note t2MOVr cannot be used.
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), DestReg)
+ .addReg(BaseReg)
+ .setMIFlags(MIFlags)
+ .add(predOps(ARMCC::AL));
+ BaseReg = ARM::SP;
+ continue;
+ }
+
+ bool HasCCOut = true;
+ if (BaseReg == ARM::SP) {
+ // sub sp, sp, #imm7
+ if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
+ assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?");
+ Opc = isSub ? ARM::tSUBspi : ARM::tADDspi;
+ BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
+ .addReg(BaseReg)
+ .addImm(ThisVal / 4)
+ .setMIFlags(MIFlags)
+ .add(predOps(ARMCC::AL));
+ NumBytes = 0;
+ continue;
+ }
+
+ // sub rd, sp, so_imm
+ Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri;
+ if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
+ NumBytes = 0;
+ } else {
+ // FIXME: Move this to ARMAddressingModes.h?
+ unsigned RotAmt = countLeadingZeros(ThisVal);
+ ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
+ NumBytes &= ~ThisVal;
+ assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
+ "Bit extraction didn't work?");
+ }
+ } else {
+ assert(DestReg != ARM::SP && BaseReg != ARM::SP);
+ Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri;
+ if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
+ NumBytes = 0;
+ } else if (ThisVal < 4096) {
+ Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
+ HasCCOut = false;
+ NumBytes = 0;
+ } else {
+ // FIXME: Move this to ARMAddressingModes.h?
+ unsigned RotAmt = countLeadingZeros(ThisVal);
+ ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
+ NumBytes &= ~ThisVal;
+ assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
+ "Bit extraction didn't work?");
+ }
+ }
+
+ // Build the new ADD / SUB.
+ MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
+ .addReg(BaseReg, RegState::Kill)
+ .addImm(ThisVal)
+ .add(predOps(ARMCC::AL))
+ .setMIFlags(MIFlags);
+ if (HasCCOut)
+ MIB.add(condCodeOp());
+
+ BaseReg = DestReg;
+ }
+}
+
+static unsigned
+negativeOffsetOpcode(unsigned opcode)
+{
+ switch (opcode) {
+ case ARM::t2LDRi12: return ARM::t2LDRi8;
+ case ARM::t2LDRHi12: return ARM::t2LDRHi8;
+ case ARM::t2LDRBi12: return ARM::t2LDRBi8;
+ case ARM::t2LDRSHi12: return ARM::t2LDRSHi8;
+ case ARM::t2LDRSBi12: return ARM::t2LDRSBi8;
+ case ARM::t2STRi12: return ARM::t2STRi8;
+ case ARM::t2STRBi12: return ARM::t2STRBi8;
+ case ARM::t2STRHi12: return ARM::t2STRHi8;
+ case ARM::t2PLDi12: return ARM::t2PLDi8;
+
+ case ARM::t2LDRi8:
+ case ARM::t2LDRHi8:
+ case ARM::t2LDRBi8:
+ case ARM::t2LDRSHi8:
+ case ARM::t2LDRSBi8:
+ case ARM::t2STRi8:
+ case ARM::t2STRBi8:
+ case ARM::t2STRHi8:
+ case ARM::t2PLDi8:
+ return opcode;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static unsigned
+positiveOffsetOpcode(unsigned opcode)
+{
+ switch (opcode) {
+ case ARM::t2LDRi8: return ARM::t2LDRi12;
+ case ARM::t2LDRHi8: return ARM::t2LDRHi12;
+ case ARM::t2LDRBi8: return ARM::t2LDRBi12;
+ case ARM::t2LDRSHi8: return ARM::t2LDRSHi12;
+ case ARM::t2LDRSBi8: return ARM::t2LDRSBi12;
+ case ARM::t2STRi8: return ARM::t2STRi12;
+ case ARM::t2STRBi8: return ARM::t2STRBi12;
+ case ARM::t2STRHi8: return ARM::t2STRHi12;
+ case ARM::t2PLDi8: return ARM::t2PLDi12;
+
+ case ARM::t2LDRi12:
+ case ARM::t2LDRHi12:
+ case ARM::t2LDRBi12:
+ case ARM::t2LDRSHi12:
+ case ARM::t2LDRSBi12:
+ case ARM::t2STRi12:
+ case ARM::t2STRBi12:
+ case ARM::t2STRHi12:
+ case ARM::t2PLDi12:
+ return opcode;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static unsigned
+immediateOffsetOpcode(unsigned opcode)
+{
+ switch (opcode) {
+ case ARM::t2LDRs: return ARM::t2LDRi12;
+ case ARM::t2LDRHs: return ARM::t2LDRHi12;
+ case ARM::t2LDRBs: return ARM::t2LDRBi12;
+ case ARM::t2LDRSHs: return ARM::t2LDRSHi12;
+ case ARM::t2LDRSBs: return ARM::t2LDRSBi12;
+ case ARM::t2STRs: return ARM::t2STRi12;
+ case ARM::t2STRBs: return ARM::t2STRBi12;
+ case ARM::t2STRHs: return ARM::t2STRHi12;
+ case ARM::t2PLDs: return ARM::t2PLDi12;
+
+ case ARM::t2LDRi12:
+ case ARM::t2LDRHi12:
+ case ARM::t2LDRBi12:
+ case ARM::t2LDRSHi12:
+ case ARM::t2LDRSBi12:
+ case ARM::t2STRi12:
+ case ARM::t2STRBi12:
+ case ARM::t2STRHi12:
+ case ARM::t2PLDi12:
+ case ARM::t2LDRi8:
+ case ARM::t2LDRHi8:
+ case ARM::t2LDRBi8:
+ case ARM::t2LDRSHi8:
+ case ARM::t2LDRSBi8:
+ case ARM::t2STRi8:
+ case ARM::t2STRBi8:
+ case ARM::t2STRHi8:
+ case ARM::t2PLDi8:
+ return opcode;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+bool llvm::rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
+ unsigned FrameReg, int &Offset,
+ const ARMBaseInstrInfo &TII) {
+ unsigned Opcode = MI.getOpcode();
+ const MCInstrDesc &Desc = MI.getDesc();
+ unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
+ bool isSub = false;
+
+ // Memory operands in inline assembly always use AddrModeT2_i12.
+ if (Opcode == ARM::INLINEASM)
+ AddrMode = ARMII::AddrModeT2_i12; // FIXME. mode for thumb2?
+
+ if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) {
+ Offset += MI.getOperand(FrameRegIdx+1).getImm();
+
+ unsigned PredReg;
+ if (Offset == 0 && getInstrPredicate(MI, PredReg) == ARMCC::AL) {
+ // Turn it into a move.
+ MI.setDesc(TII.get(ARM::tMOVr));
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ // Remove offset and remaining explicit predicate operands.
+ do MI.RemoveOperand(FrameRegIdx+1);
+ while (MI.getNumOperands() > FrameRegIdx+1);
+ MachineInstrBuilder MIB(*MI.getParent()->getParent(), &MI);
+ MIB.add(predOps(ARMCC::AL));
+ return true;
+ }
+
+ bool HasCCOut = Opcode != ARM::t2ADDri12;
+
+ if (Offset < 0) {
+ Offset = -Offset;
+ isSub = true;
+ MI.setDesc(TII.get(ARM::t2SUBri));
+ } else {
+ MI.setDesc(TII.get(ARM::t2ADDri));
+ }
+
+ // Common case: small offset, fits into instruction.
+ if (ARM_AM::getT2SOImmVal(Offset) != -1) {
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
+ // Add cc_out operand if the original instruction did not have one.
+ if (!HasCCOut)
+ MI.addOperand(MachineOperand::CreateReg(0, false));
+ Offset = 0;
+ return true;
+ }
+ // Another common case: imm12.
+ if (Offset < 4096 &&
+ (!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) {
+ unsigned NewOpc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
+ MI.setDesc(TII.get(NewOpc));
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
+ // Remove the cc_out operand.
+ if (HasCCOut)
+ MI.RemoveOperand(MI.getNumOperands()-1);
+ Offset = 0;
+ return true;
+ }
+
+ // Otherwise, extract 8 adjacent bits from the immediate into this
+ // t2ADDri/t2SUBri.
+ unsigned RotAmt = countLeadingZeros<unsigned>(Offset);
+ unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xff000000U, RotAmt);
+
+ // We will handle these bits from offset, clear them.
+ Offset &= ~ThisImmVal;
+
+ assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 &&
+ "Bit extraction didn't work?");
+ MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
+ // Add cc_out operand if the original instruction did not have one.
+ if (!HasCCOut)
+ MI.addOperand(MachineOperand::CreateReg(0, false));
+ } else {
+ // AddrMode4 and AddrMode6 cannot handle any offset.
+ if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
+ return false;
+
+ // AddrModeT2_so cannot handle any offset. If there is no offset
+ // register then we change to an immediate version.
+ unsigned NewOpc = Opcode;
+ if (AddrMode == ARMII::AddrModeT2_so) {
+ unsigned OffsetReg = MI.getOperand(FrameRegIdx+1).getReg();
+ if (OffsetReg != 0) {
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ return Offset == 0;
+ }
+
+ MI.RemoveOperand(FrameRegIdx+1);
+ MI.getOperand(FrameRegIdx+1).ChangeToImmediate(0);
+ NewOpc = immediateOffsetOpcode(Opcode);
+ AddrMode = ARMII::AddrModeT2_i12;
+ }
+
+ unsigned NumBits = 0;
+ unsigned Scale = 1;
+ if (AddrMode == ARMII::AddrModeT2_i8 || AddrMode == ARMII::AddrModeT2_i12) {
+ // i8 supports only negative, and i12 supports only positive, so
+ // based on Offset sign convert Opcode to the appropriate
+ // instruction
+ Offset += MI.getOperand(FrameRegIdx+1).getImm();
+ if (Offset < 0) {
+ NewOpc = negativeOffsetOpcode(Opcode);
+ NumBits = 8;
+ isSub = true;
+ Offset = -Offset;
+ } else {
+ NewOpc = positiveOffsetOpcode(Opcode);
+ NumBits = 12;
+ }
+ } else if (AddrMode == ARMII::AddrMode5) {
+ // VFP address mode.
+ const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
+ int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
+ if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
+ InstrOffs *= -1;
+ NumBits = 8;
+ Scale = 4;
+ Offset += InstrOffs * 4;
+ assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
+ if (Offset < 0) {
+ Offset = -Offset;
+ isSub = true;
+ }
+ } else if (AddrMode == ARMII::AddrModeT2_i8s4) {
+ Offset += MI.getOperand(FrameRegIdx + 1).getImm() * 4;
+ NumBits = 10; // 8 bits scaled by 4
+ // MCInst operand expects already scaled value.
+ Scale = 1;
+ assert((Offset & 3) == 0 && "Can't encode this offset!");
+ } else {
+ llvm_unreachable("Unsupported addressing mode!");
+ }
+
+ if (NewOpc != Opcode)
+ MI.setDesc(TII.get(NewOpc));
+
+ MachineOperand &ImmOp = MI.getOperand(FrameRegIdx+1);
+
+ // Attempt to fold address computation
+ // Common case: small offset, fits into instruction.
+ int ImmedOffset = Offset / Scale;
+ unsigned Mask = (1 << NumBits) - 1;
+ if ((unsigned)Offset <= Mask * Scale) {
+ // Replace the FrameIndex with fp/sp
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ if (isSub) {
+ if (AddrMode == ARMII::AddrMode5)
+ // FIXME: Not consistent.
+ ImmedOffset |= 1 << NumBits;
+ else
+ ImmedOffset = -ImmedOffset;
+ }
+ ImmOp.ChangeToImmediate(ImmedOffset);
+ Offset = 0;
+ return true;
+ }
+
+ // Otherwise, offset doesn't fit. Pull in what we can to simplify
+ ImmedOffset = ImmedOffset & Mask;
+ if (isSub) {
+ if (AddrMode == ARMII::AddrMode5)
+ // FIXME: Not consistent.
+ ImmedOffset |= 1 << NumBits;
+ else {
+ ImmedOffset = -ImmedOffset;
+ if (ImmedOffset == 0)
+ // Change the opcode back if the encoded offset is zero.
+ MI.setDesc(TII.get(positiveOffsetOpcode(NewOpc)));
+ }
+ }
+ ImmOp.ChangeToImmediate(ImmedOffset);
+ Offset &= ~(Mask*Scale);
+ }
+
+ Offset = (isSub) ? -Offset : Offset;
+ return Offset == 0;
+}
+
+ARMCC::CondCodes llvm::getITInstrPredicate(const MachineInstr &MI,
+ unsigned &PredReg) {
+ unsigned Opc = MI.getOpcode();
+ if (Opc == ARM::tBcc || Opc == ARM::t2Bcc)
+ return ARMCC::AL;
+ return getInstrPredicate(MI, PredReg);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-04 21:38:25 +0000