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diff --git a/lib/Target/AArch64/AArch64ExpandPseudoInsts.cpp b/lib/Target/AArch64/AArch64ExpandPseudoInsts.cpp
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+//==-- AArch64ExpandPseudoInsts.cpp - Expand pseudo instructions --*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a pass that expands pseudo instructions into target
+// instructions to allow proper scheduling and other late optimizations. This
+// pass should be run after register allocation but before the post-regalloc
+// scheduling pass.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/AArch64AddressingModes.h"
+#include "AArch64InstrInfo.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/Support/MathExtras.h"
+using namespace llvm;
+
+namespace {
+class AArch64ExpandPseudo : public MachineFunctionPass {
+public:
+ static char ID;
+ AArch64ExpandPseudo() : MachineFunctionPass(ID) {}
+
+ const AArch64InstrInfo *TII;
+
+ bool runOnMachineFunction(MachineFunction &Fn) override;
+
+ const char *getPassName() const override {
+ return "AArch64 pseudo instruction expansion pass";
+ }
+
+private:
+ bool expandMBB(MachineBasicBlock &MBB);
+ bool expandMI(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI);
+ bool expandMOVImm(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI,
+ unsigned BitSize);
+};
+char AArch64ExpandPseudo::ID = 0;
+}
+
+/// \brief Transfer implicit operands on the pseudo instruction to the
+/// instructions created from the expansion.
+static void transferImpOps(MachineInstr &OldMI, MachineInstrBuilder &UseMI,
+ MachineInstrBuilder &DefMI) {
+ const MCInstrDesc &Desc = OldMI.getDesc();
+ for (unsigned i = Desc.getNumOperands(), e = OldMI.getNumOperands(); i != e;
+ ++i) {
+ const MachineOperand &MO = OldMI.getOperand(i);
+ assert(MO.isReg() && MO.getReg());
+ if (MO.isUse())
+ UseMI.addOperand(MO);
+ else
+ DefMI.addOperand(MO);
+ }
+}
+
+/// \brief Helper function which extracts the specified 16-bit chunk from a
+/// 64-bit value.
+static uint64_t getChunk(uint64_t Imm, unsigned ChunkIdx) {
+ assert(ChunkIdx < 4 && "Out of range chunk index specified!");
+
+ return (Imm >> (ChunkIdx * 16)) & 0xFFFF;
+}
+
+/// \brief Helper function which replicates a 16-bit chunk within a 64-bit
+/// value. Indices correspond to element numbers in a v4i16.
+static uint64_t replicateChunk(uint64_t Imm, unsigned FromIdx, unsigned ToIdx) {
+ assert((FromIdx < 4) && (ToIdx < 4) && "Out of range chunk index specified!");
+ const unsigned ShiftAmt = ToIdx * 16;
+
+ // Replicate the source chunk to the destination position.
+ const uint64_t Chunk = getChunk(Imm, FromIdx) << ShiftAmt;
+ // Clear the destination chunk.
+ Imm &= ~(0xFFFFLL << ShiftAmt);
+ // Insert the replicated chunk.
+ return Imm | Chunk;
+}
+
+/// \brief Helper function which tries to materialize a 64-bit value with an
+/// ORR + MOVK instruction sequence.
+static bool tryOrrMovk(uint64_t UImm, uint64_t OrrImm, MachineInstr &MI,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ const AArch64InstrInfo *TII, unsigned ChunkIdx) {
+ assert(ChunkIdx < 4 && "Out of range chunk index specified!");
+ const unsigned ShiftAmt = ChunkIdx * 16;
+
+ uint64_t Encoding;
+ if (AArch64_AM::processLogicalImmediate(OrrImm, 64, Encoding)) {
+ // Create the ORR-immediate instruction.
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ORRXri))
+ .addOperand(MI.getOperand(0))
+ .addReg(AArch64::XZR)
+ .addImm(Encoding);
+
+ // Create the MOVK instruction.
+ const unsigned Imm16 = getChunk(UImm, ChunkIdx);
+ const unsigned DstReg = MI.getOperand(0).getReg();
+ const bool DstIsDead = MI.getOperand(0).isDead();
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::MOVKXi))
+ .addReg(DstReg, RegState::Define | getDeadRegState(DstIsDead))
+ .addReg(DstReg)
+ .addImm(Imm16)
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, ShiftAmt));
+
+ transferImpOps(MI, MIB, MIB1);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ return false;
+}
+
+/// \brief Check whether the given 16-bit chunk replicated to full 64-bit width
+/// can be materialized with an ORR instruction.
+static bool canUseOrr(uint64_t Chunk, uint64_t &Encoding) {
+ Chunk = (Chunk << 48) | (Chunk << 32) | (Chunk << 16) | Chunk;
+
+ return AArch64_AM::processLogicalImmediate(Chunk, 64, Encoding);
+}
+
+/// \brief Check for identical 16-bit chunks within the constant and if so
+/// materialize them with a single ORR instruction. The remaining one or two
+/// 16-bit chunks will be materialized with MOVK instructions.
+///
+/// This allows us to materialize constants like |A|B|A|A| or |A|B|C|A| (order
+/// of the chunks doesn't matter), assuming |A|A|A|A| can be materialized with
+/// an ORR instruction.
+///
+static bool tryToreplicateChunks(uint64_t UImm, MachineInstr &MI,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ const AArch64InstrInfo *TII) {
+ typedef DenseMap<uint64_t, unsigned> CountMap;
+ CountMap Counts;
+
+ // Scan the constant and count how often every chunk occurs.
+ for (unsigned Idx = 0; Idx < 4; ++Idx)
+ ++Counts[getChunk(UImm, Idx)];
+
+ // Traverse the chunks to find one which occurs more than once.
+ for (CountMap::const_iterator Chunk = Counts.begin(), End = Counts.end();
+ Chunk != End; ++Chunk) {
+ const uint64_t ChunkVal = Chunk->first;
+ const unsigned Count = Chunk->second;
+
+ uint64_t Encoding = 0;
+
+ // We are looking for chunks which have two or three instances and can be
+ // materialized with an ORR instruction.
+ if ((Count != 2 && Count != 3) || !canUseOrr(ChunkVal, Encoding))
+ continue;
+
+ const bool CountThree = Count == 3;
+ // Create the ORR-immediate instruction.
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ORRXri))
+ .addOperand(MI.getOperand(0))
+ .addReg(AArch64::XZR)
+ .addImm(Encoding);
+
+ const unsigned DstReg = MI.getOperand(0).getReg();
+ const bool DstIsDead = MI.getOperand(0).isDead();
+
+ unsigned ShiftAmt = 0;
+ uint64_t Imm16 = 0;
+ // Find the first chunk not materialized with the ORR instruction.
+ for (; ShiftAmt < 64; ShiftAmt += 16) {
+ Imm16 = (UImm >> ShiftAmt) & 0xFFFF;
+
+ if (Imm16 != ChunkVal)
+ break;
+ }
+
+ // Create the first MOVK instruction.
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::MOVKXi))
+ .addReg(DstReg,
+ RegState::Define | getDeadRegState(DstIsDead && CountThree))
+ .addReg(DstReg)
+ .addImm(Imm16)
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, ShiftAmt));
+
+ // In case we have three instances the whole constant is now materialized
+ // and we can exit.
+ if (CountThree) {
+ transferImpOps(MI, MIB, MIB1);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ // Find the remaining chunk which needs to be materialized.
+ for (ShiftAmt += 16; ShiftAmt < 64; ShiftAmt += 16) {
+ Imm16 = (UImm >> ShiftAmt) & 0xFFFF;
+
+ if (Imm16 != ChunkVal)
+ break;
+ }
+
+ // Create the second MOVK instruction.
+ MachineInstrBuilder MIB2 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::MOVKXi))
+ .addReg(DstReg, RegState::Define | getDeadRegState(DstIsDead))
+ .addReg(DstReg)
+ .addImm(Imm16)
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, ShiftAmt));
+
+ transferImpOps(MI, MIB, MIB2);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ return false;
+}
+
+/// \brief Check whether this chunk matches the pattern '1...0...'. This pattern
+/// starts a contiguous sequence of ones if we look at the bits from the LSB
+/// towards the MSB.
+static bool isStartChunk(uint64_t Chunk) {
+ if (Chunk == 0 || Chunk == UINT64_MAX)
+ return false;
+
+ return (CountLeadingOnes_64(Chunk) + countTrailingZeros(Chunk)) == 64;
+}
+
+/// \brief Check whether this chunk matches the pattern '0...1...' This pattern
+/// ends a contiguous sequence of ones if we look at the bits from the LSB
+/// towards the MSB.
+static bool isEndChunk(uint64_t Chunk) {
+ if (Chunk == 0 || Chunk == UINT64_MAX)
+ return false;
+
+ return (countLeadingZeros(Chunk) + CountTrailingOnes_64(Chunk)) == 64;
+}
+
+/// \brief Clear or set all bits in the chunk at the given index.
+static uint64_t updateImm(uint64_t Imm, unsigned Idx, bool Clear) {
+ const uint64_t Mask = 0xFFFF;
+
+ if (Clear)
+ // Clear chunk in the immediate.
+ Imm &= ~(Mask << (Idx * 16));
+ else
+ // Set all bits in the immediate for the particular chunk.
+ Imm |= Mask << (Idx * 16);
+
+ return Imm;
+}
+
+/// \brief Check whether the constant contains a sequence of contiguous ones,
+/// which might be interrupted by one or two chunks. If so, materialize the
+/// sequence of contiguous ones with an ORR instruction.
+/// Materialize the chunks which are either interrupting the sequence or outside
+/// of the sequence with a MOVK instruction.
+///
+/// Assuming S is a chunk which starts the sequence (1...0...), E is a chunk
+/// which ends the sequence (0...1...). Then we are looking for constants which
+/// contain at least one S and E chunk.
+/// E.g. |E|A|B|S|, |A|E|B|S| or |A|B|E|S|.
+///
+/// We are also looking for constants like |S|A|B|E| where the contiguous
+/// sequence of ones wraps around the MSB into the LSB.
+///
+static bool trySequenceOfOnes(uint64_t UImm, MachineInstr &MI,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ const AArch64InstrInfo *TII) {
+ const int NotSet = -1;
+ const uint64_t Mask = 0xFFFF;
+
+ int StartIdx = NotSet;
+ int EndIdx = NotSet;
+ // Try to find the chunks which start/end a contiguous sequence of ones.
+ for (int Idx = 0; Idx < 4; ++Idx) {
+ int64_t Chunk = getChunk(UImm, Idx);
+ // Sign extend the 16-bit chunk to 64-bit.
+ Chunk = (Chunk << 48) >> 48;
+
+ if (isStartChunk(Chunk))
+ StartIdx = Idx;
+ else if (isEndChunk(Chunk))
+ EndIdx = Idx;
+ }
+
+ // Early exit in case we can't find a start/end chunk.
+ if (StartIdx == NotSet || EndIdx == NotSet)
+ return false;
+
+ // Outside of the contiguous sequence of ones everything needs to be zero.
+ uint64_t Outside = 0;
+ // Chunks between the start and end chunk need to have all their bits set.
+ uint64_t Inside = Mask;
+
+ // If our contiguous sequence of ones wraps around from the MSB into the LSB,
+ // just swap indices and pretend we are materializing a contiguous sequence
+ // of zeros surrounded by a contiguous sequence of ones.
+ if (StartIdx > EndIdx) {
+ std::swap(StartIdx, EndIdx);
+ std::swap(Outside, Inside);
+ }
+
+ uint64_t OrrImm = UImm;
+ int FirstMovkIdx = NotSet;
+ int SecondMovkIdx = NotSet;
+
+ // Find out which chunks we need to patch up to obtain a contiguous sequence
+ // of ones.
+ for (int Idx = 0; Idx < 4; ++Idx) {
+ const uint64_t Chunk = getChunk(UImm, Idx);
+
+ // Check whether we are looking at a chunk which is not part of the
+ // contiguous sequence of ones.
+ if ((Idx < StartIdx || EndIdx < Idx) && Chunk != Outside) {
+ OrrImm = updateImm(OrrImm, Idx, Outside == 0);
+
+ // Remember the index we need to patch.
+ if (FirstMovkIdx == NotSet)
+ FirstMovkIdx = Idx;
+ else
+ SecondMovkIdx = Idx;
+
+ // Check whether we are looking a chunk which is part of the contiguous
+ // sequence of ones.
+ } else if (Idx > StartIdx && Idx < EndIdx && Chunk != Inside) {
+ OrrImm = updateImm(OrrImm, Idx, Inside != Mask);
+
+ // Remember the index we need to patch.
+ if (FirstMovkIdx == NotSet)
+ FirstMovkIdx = Idx;
+ else
+ SecondMovkIdx = Idx;
+ }
+ }
+ assert(FirstMovkIdx != NotSet && "Constant materializable with single ORR!");
+
+ // Create the ORR-immediate instruction.
+ uint64_t Encoding = 0;
+ AArch64_AM::processLogicalImmediate(OrrImm, 64, Encoding);
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ORRXri))
+ .addOperand(MI.getOperand(0))
+ .addReg(AArch64::XZR)
+ .addImm(Encoding);
+
+ const unsigned DstReg = MI.getOperand(0).getReg();
+ const bool DstIsDead = MI.getOperand(0).isDead();
+
+ const bool SingleMovk = SecondMovkIdx == NotSet;
+ // Create the first MOVK instruction.
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::MOVKXi))
+ .addReg(DstReg,
+ RegState::Define | getDeadRegState(DstIsDead && SingleMovk))
+ .addReg(DstReg)
+ .addImm(getChunk(UImm, FirstMovkIdx))
+ .addImm(
+ AArch64_AM::getShifterImm(AArch64_AM::LSL, FirstMovkIdx * 16));
+
+ // Early exit in case we only need to emit a single MOVK instruction.
+ if (SingleMovk) {
+ transferImpOps(MI, MIB, MIB1);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ // Create the second MOVK instruction.
+ MachineInstrBuilder MIB2 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::MOVKXi))
+ .addReg(DstReg, RegState::Define | getDeadRegState(DstIsDead))
+ .addReg(DstReg)
+ .addImm(getChunk(UImm, SecondMovkIdx))
+ .addImm(
+ AArch64_AM::getShifterImm(AArch64_AM::LSL, SecondMovkIdx * 16));
+
+ transferImpOps(MI, MIB, MIB2);
+ MI.eraseFromParent();
+ return true;
+}
+
+/// \brief Expand a MOVi32imm or MOVi64imm pseudo instruction to one or more
+/// real move-immediate instructions to synthesize the immediate.
+bool AArch64ExpandPseudo::expandMOVImm(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ unsigned BitSize) {
+ MachineInstr &MI = *MBBI;
+ uint64_t Imm = MI.getOperand(1).getImm();
+ const unsigned Mask = 0xFFFF;
+
+ // Try a MOVI instruction (aka ORR-immediate with the zero register).
+ uint64_t UImm = Imm << (64 - BitSize) >> (64 - BitSize);
+ uint64_t Encoding;
+ if (AArch64_AM::processLogicalImmediate(UImm, BitSize, Encoding)) {
+ unsigned Opc = (BitSize == 32 ? AArch64::ORRWri : AArch64::ORRXri);
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(Opc))
+ .addOperand(MI.getOperand(0))
+ .addReg(BitSize == 32 ? AArch64::WZR : AArch64::XZR)
+ .addImm(Encoding);
+ transferImpOps(MI, MIB, MIB);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ // Scan the immediate and count the number of 16-bit chunks which are either
+ // all ones or all zeros.
+ unsigned OneChunks = 0;
+ unsigned ZeroChunks = 0;
+ for (unsigned Shift = 0; Shift < BitSize; Shift += 16) {
+ const unsigned Chunk = (Imm >> Shift) & Mask;
+ if (Chunk == Mask)
+ OneChunks++;
+ else if (Chunk == 0)
+ ZeroChunks++;
+ }
+
+ // Since we can't materialize the constant with a single ORR instruction,
+ // let's see whether we can materialize 3/4 of the constant with an ORR
+ // instruction and use an additional MOVK instruction to materialize the
+ // remaining 1/4.
+ //
+ // We are looking for constants with a pattern like: |A|X|B|X| or |X|A|X|B|.
+ //
+ // E.g. assuming |A|X|A|X| is a pattern which can be materialized with ORR,
+ // we would create the following instruction sequence:
+ //
+ // ORR x0, xzr, |A|X|A|X|
+ // MOVK x0, |B|, LSL #16
+ //
+ // Only look at 64-bit constants which can't be materialized with a single
+ // instruction e.g. which have less than either three all zero or all one
+ // chunks.
+ //
+ // Ignore 32-bit constants here, they always can be materialized with a
+ // MOVZ/MOVN + MOVK pair. Since the 32-bit constant can't be materialized
+ // with a single ORR, the best sequence we can achieve is a ORR + MOVK pair.
+ // Thus we fall back to the default code below which in the best case creates
+ // a single MOVZ/MOVN instruction (in case one chunk is all zero or all one).
+ //
+ if (BitSize == 64 && OneChunks < 3 && ZeroChunks < 3) {
+ // If we interpret the 64-bit constant as a v4i16, are elements 0 and 2
+ // identical?
+ if (getChunk(UImm, 0) == getChunk(UImm, 2)) {
+ // See if we can come up with a constant which can be materialized with
+ // ORR-immediate by replicating element 3 into element 1.
+ uint64_t OrrImm = replicateChunk(UImm, 3, 1);
+ if (tryOrrMovk(UImm, OrrImm, MI, MBB, MBBI, TII, 1))
+ return true;
+
+ // See if we can come up with a constant which can be materialized with
+ // ORR-immediate by replicating element 1 into element 3.
+ OrrImm = replicateChunk(UImm, 1, 3);
+ if (tryOrrMovk(UImm, OrrImm, MI, MBB, MBBI, TII, 3))
+ return true;
+
+ // If we interpret the 64-bit constant as a v4i16, are elements 1 and 3
+ // identical?
+ } else if (getChunk(UImm, 1) == getChunk(UImm, 3)) {
+ // See if we can come up with a constant which can be materialized with
+ // ORR-immediate by replicating element 2 into element 0.
+ uint64_t OrrImm = replicateChunk(UImm, 2, 0);
+ if (tryOrrMovk(UImm, OrrImm, MI, MBB, MBBI, TII, 0))
+ return true;
+
+ // See if we can come up with a constant which can be materialized with
+ // ORR-immediate by replicating element 1 into element 3.
+ OrrImm = replicateChunk(UImm, 0, 2);
+ if (tryOrrMovk(UImm, OrrImm, MI, MBB, MBBI, TII, 2))
+ return true;
+ }
+ }
+
+ // Check for identical 16-bit chunks within the constant and if so materialize
+ // them with a single ORR instruction. The remaining one or two 16-bit chunks
+ // will be materialized with MOVK instructions.
+ if (BitSize == 64 && tryToreplicateChunks(UImm, MI, MBB, MBBI, TII))
+ return true;
+
+ // Check whether the constant contains a sequence of contiguous ones, which
+ // might be interrupted by one or two chunks. If so, materialize the sequence
+ // of contiguous ones with an ORR instruction. Materialize the chunks which
+ // are either interrupting the sequence or outside of the sequence with a
+ // MOVK instruction.
+ if (BitSize == 64 && trySequenceOfOnes(UImm, MI, MBB, MBBI, TII))
+ return true;
+
+ // Use a MOVZ or MOVN instruction to set the high bits, followed by one or
+ // more MOVK instructions to insert additional 16-bit portions into the
+ // lower bits.
+ bool isNeg = false;
+
+ // Use MOVN to materialize the high bits if we have more all one chunks
+ // than all zero chunks.
+ if (OneChunks > ZeroChunks) {
+ isNeg = true;
+ Imm = ~Imm;
+ }
+
+ unsigned FirstOpc;
+ if (BitSize == 32) {
+ Imm &= (1LL << 32) - 1;
+ FirstOpc = (isNeg ? AArch64::MOVNWi : AArch64::MOVZWi);
+ } else {
+ FirstOpc = (isNeg ? AArch64::MOVNXi : AArch64::MOVZXi);
+ }
+ unsigned Shift = 0; // LSL amount for high bits with MOVZ/MOVN
+ unsigned LastShift = 0; // LSL amount for last MOVK
+ if (Imm != 0) {
+ unsigned LZ = countLeadingZeros(Imm);
+ unsigned TZ = countTrailingZeros(Imm);
+ Shift = ((63 - LZ) / 16) * 16;
+ LastShift = (TZ / 16) * 16;
+ }
+ unsigned Imm16 = (Imm >> Shift) & Mask;
+ unsigned DstReg = MI.getOperand(0).getReg();
+ bool DstIsDead = MI.getOperand(0).isDead();
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(FirstOpc))
+ .addReg(DstReg, RegState::Define |
+ getDeadRegState(DstIsDead && Shift == LastShift))
+ .addImm(Imm16)
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, Shift));
+
+ // If a MOVN was used for the high bits of a negative value, flip the rest
+ // of the bits back for use with MOVK.
+ if (isNeg)
+ Imm = ~Imm;
+
+ if (Shift == LastShift) {
+ transferImpOps(MI, MIB1, MIB1);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ MachineInstrBuilder MIB2;
+ unsigned Opc = (BitSize == 32 ? AArch64::MOVKWi : AArch64::MOVKXi);
+ while (Shift != LastShift) {
+ Shift -= 16;
+ Imm16 = (Imm >> Shift) & Mask;
+ if (Imm16 == (isNeg ? Mask : 0))
+ continue; // This 16-bit portion is already set correctly.
+ MIB2 = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(Opc))
+ .addReg(DstReg,
+ RegState::Define |
+ getDeadRegState(DstIsDead && Shift == LastShift))
+ .addReg(DstReg)
+ .addImm(Imm16)
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, Shift));
+ }
+
+ transferImpOps(MI, MIB1, MIB2);
+ MI.eraseFromParent();
+ return true;
+}
+
+/// \brief If MBBI references a pseudo instruction that should be expanded here,
+/// do the expansion and return true. Otherwise return false.
+bool AArch64ExpandPseudo::expandMI(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI) {
+ MachineInstr &MI = *MBBI;
+ unsigned Opcode = MI.getOpcode();
+ switch (Opcode) {
+ default:
+ break;
+
+ case AArch64::ADDWrr:
+ case AArch64::SUBWrr:
+ case AArch64::ADDXrr:
+ case AArch64::SUBXrr:
+ case AArch64::ADDSWrr:
+ case AArch64::SUBSWrr:
+ case AArch64::ADDSXrr:
+ case AArch64::SUBSXrr:
+ case AArch64::ANDWrr:
+ case AArch64::ANDXrr:
+ case AArch64::BICWrr:
+ case AArch64::BICXrr:
+ case AArch64::ANDSWrr:
+ case AArch64::ANDSXrr:
+ case AArch64::BICSWrr:
+ case AArch64::BICSXrr:
+ case AArch64::EONWrr:
+ case AArch64::EONXrr:
+ case AArch64::EORWrr:
+ case AArch64::EORXrr:
+ case AArch64::ORNWrr:
+ case AArch64::ORNXrr:
+ case AArch64::ORRWrr:
+ case AArch64::ORRXrr: {
+ unsigned Opcode;
+ switch (MI.getOpcode()) {
+ default:
+ return false;
+ case AArch64::ADDWrr: Opcode = AArch64::ADDWrs; break;
+ case AArch64::SUBWrr: Opcode = AArch64::SUBWrs; break;
+ case AArch64::ADDXrr: Opcode = AArch64::ADDXrs; break;
+ case AArch64::SUBXrr: Opcode = AArch64::SUBXrs; break;
+ case AArch64::ADDSWrr: Opcode = AArch64::ADDSWrs; break;
+ case AArch64::SUBSWrr: Opcode = AArch64::SUBSWrs; break;
+ case AArch64::ADDSXrr: Opcode = AArch64::ADDSXrs; break;
+ case AArch64::SUBSXrr: Opcode = AArch64::SUBSXrs; break;
+ case AArch64::ANDWrr: Opcode = AArch64::ANDWrs; break;
+ case AArch64::ANDXrr: Opcode = AArch64::ANDXrs; break;
+ case AArch64::BICWrr: Opcode = AArch64::BICWrs; break;
+ case AArch64::BICXrr: Opcode = AArch64::BICXrs; break;
+ case AArch64::ANDSWrr: Opcode = AArch64::ANDSWrs; break;
+ case AArch64::ANDSXrr: Opcode = AArch64::ANDSXrs; break;
+ case AArch64::BICSWrr: Opcode = AArch64::BICSWrs; break;
+ case AArch64::BICSXrr: Opcode = AArch64::BICSXrs; break;
+ case AArch64::EONWrr: Opcode = AArch64::EONWrs; break;
+ case AArch64::EONXrr: Opcode = AArch64::EONXrs; break;
+ case AArch64::EORWrr: Opcode = AArch64::EORWrs; break;
+ case AArch64::EORXrr: Opcode = AArch64::EORXrs; break;
+ case AArch64::ORNWrr: Opcode = AArch64::ORNWrs; break;
+ case AArch64::ORNXrr: Opcode = AArch64::ORNXrs; break;
+ case AArch64::ORRWrr: Opcode = AArch64::ORRWrs; break;
+ case AArch64::ORRXrr: Opcode = AArch64::ORRXrs; break;
+ }
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(Opcode),
+ MI.getOperand(0).getReg())
+ .addOperand(MI.getOperand(1))
+ .addOperand(MI.getOperand(2))
+ .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0));
+ transferImpOps(MI, MIB1, MIB1);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ case AArch64::FCVTSHpseudo: {
+ MachineOperand Src = MI.getOperand(1);
+ Src.setImplicit();
+ unsigned SrcH =
+ TII->getRegisterInfo().getSubReg(Src.getReg(), AArch64::hsub);
+ auto MIB = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::FCVTSHr))
+ .addOperand(MI.getOperand(0))
+ .addReg(SrcH, RegState::Undef)
+ .addOperand(Src);
+ transferImpOps(MI, MIB, MIB);
+ MI.eraseFromParent();
+ return true;
+ }
+ case AArch64::LOADgot: {
+ // Expand into ADRP + LDR.
+ unsigned DstReg = MI.getOperand(0).getReg();
+ const MachineOperand &MO1 = MI.getOperand(1);
+ unsigned Flags = MO1.getTargetFlags();
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ADRP), DstReg);
+ MachineInstrBuilder MIB2 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::LDRXui))
+ .addOperand(MI.getOperand(0))
+ .addReg(DstReg);
+
+ if (MO1.isGlobal()) {
+ MIB1.addGlobalAddress(MO1.getGlobal(), 0, Flags | AArch64II::MO_PAGE);
+ MIB2.addGlobalAddress(MO1.getGlobal(), 0,
+ Flags | AArch64II::MO_PAGEOFF | AArch64II::MO_NC);
+ } else if (MO1.isSymbol()) {
+ MIB1.addExternalSymbol(MO1.getSymbolName(), Flags | AArch64II::MO_PAGE);
+ MIB2.addExternalSymbol(MO1.getSymbolName(),
+ Flags | AArch64II::MO_PAGEOFF | AArch64II::MO_NC);
+ } else {
+ assert(MO1.isCPI() &&
+ "Only expect globals, externalsymbols, or constant pools");
+ MIB1.addConstantPoolIndex(MO1.getIndex(), MO1.getOffset(),
+ Flags | AArch64II::MO_PAGE);
+ MIB2.addConstantPoolIndex(MO1.getIndex(), MO1.getOffset(),
+ Flags | AArch64II::MO_PAGEOFF |
+ AArch64II::MO_NC);
+ }
+
+ transferImpOps(MI, MIB1, MIB2);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ case AArch64::MOVaddr:
+ case AArch64::MOVaddrJT:
+ case AArch64::MOVaddrCP:
+ case AArch64::MOVaddrBA:
+ case AArch64::MOVaddrTLS:
+ case AArch64::MOVaddrEXT: {
+ // Expand into ADRP + ADD.
+ unsigned DstReg = MI.getOperand(0).getReg();
+ MachineInstrBuilder MIB1 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ADRP), DstReg)
+ .addOperand(MI.getOperand(1));
+
+ MachineInstrBuilder MIB2 =
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::ADDXri))
+ .addOperand(MI.getOperand(0))
+ .addReg(DstReg)
+ .addOperand(MI.getOperand(2))
+ .addImm(0);
+
+ transferImpOps(MI, MIB1, MIB2);
+ MI.eraseFromParent();
+ return true;
+ }
+
+ case AArch64::MOVi32imm:
+ return expandMOVImm(MBB, MBBI, 32);
+ case AArch64::MOVi64imm:
+ return expandMOVImm(MBB, MBBI, 64);
+ case AArch64::RET_ReallyLR:
+ BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(AArch64::RET))
+ .addReg(AArch64::LR);
+ MI.eraseFromParent();
+ return true;
+ }
+ return false;
+}
+
+/// \brief Iterate over the instructions in basic block MBB and expand any
+/// pseudo instructions. Return true if anything was modified.
+bool AArch64ExpandPseudo::expandMBB(MachineBasicBlock &MBB) {
+ bool Modified = false;
+
+ MachineBasicBlock::iterator MBBI = MBB.begin(), E = MBB.end();
+ while (MBBI != E) {
+ MachineBasicBlock::iterator NMBBI = std::next(MBBI);
+ Modified |= expandMI(MBB, MBBI);
+ MBBI = NMBBI;
+ }
+
+ return Modified;
+}
+
+bool AArch64ExpandPseudo::runOnMachineFunction(MachineFunction &MF) {
+ TII = static_cast<const AArch64InstrInfo *>(MF.getTarget().getInstrInfo());
+
+ bool Modified = false;
+ for (auto &MBB : MF)
+ Modified |= expandMBB(MBB);
+ return Modified;
+}
+
+/// \brief Returns an instance of the pseudo instruction expansion pass.
+FunctionPass *llvm::createAArch64ExpandPseudoPass() {
+ return new AArch64ExpandPseudo();
+}