Reset trunk to 3.24.35.4

src/a64/instructions-a64.cc

-// Copyright 2013 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "v8.h"
-
-#if V8_TARGET_ARCH_A64
-
-#define A64_DEFINE_FP_STATICS
-
-#include "a64/instructions-a64.h"
-#include "a64/assembler-a64-inl.h"
-
-namespace v8 {
-namespace internal {
-
-
-bool Instruction::IsLoad() const {
-  if (Mask(LoadStoreAnyFMask) != LoadStoreAnyFixed) {
-    return false;
-  }
-
-  if (Mask(LoadStorePairAnyFMask) == LoadStorePairAnyFixed) {
-    return Mask(LoadStorePairLBit) != 0;
-  } else {
-    LoadStoreOp op = static_cast<LoadStoreOp>(Mask(LoadStoreOpMask));
-    switch (op) {
-      case LDRB_w:
-      case LDRH_w:
-      case LDR_w:
-      case LDR_x:
-      case LDRSB_w:
-      case LDRSB_x:
-      case LDRSH_w:
-      case LDRSH_x:
-      case LDRSW_x:
-      case LDR_s:
-      case LDR_d: return true;
-      default: return false;
-    }
-  }
-}
-
-
-bool Instruction::IsStore() const {
-  if (Mask(LoadStoreAnyFMask) != LoadStoreAnyFixed) {
-    return false;
-  }
-
-  if (Mask(LoadStorePairAnyFMask) == LoadStorePairAnyFixed) {
-    return Mask(LoadStorePairLBit) == 0;
-  } else {
-    LoadStoreOp op = static_cast<LoadStoreOp>(Mask(LoadStoreOpMask));
-    switch (op) {
-      case STRB_w:
-      case STRH_w:
-      case STR_w:
-      case STR_x:
-      case STR_s:
-      case STR_d: return true;
-      default: return false;
-    }
-  }
-}
-
-
-static uint64_t RotateRight(uint64_t value,
-                            unsigned int rotate,
-                            unsigned int width) {
-  ASSERT(width <= 64);
-  rotate &= 63;
-  return ((value & ((1UL << rotate) - 1UL)) << (width - rotate)) |
-         (value >> rotate);
-}
-
-
-static uint64_t RepeatBitsAcrossReg(unsigned reg_size,
-                                    uint64_t value,
-                                    unsigned width) {
-  ASSERT((width == 2) || (width == 4) || (width == 8) || (width == 16) ||
-         (width == 32));
-  ASSERT((reg_size == kWRegSize) || (reg_size == kXRegSize));
-  uint64_t result = value & ((1UL << width) - 1UL);
-  for (unsigned i = width; i < reg_size; i *= 2) {
-    result |= (result << i);
-  }
-  return result;
-}
-
-
-// Logical immediates can't encode zero, so a return value of zero is used to
-// indicate a failure case. Specifically, where the constraints on imm_s are not
-// met.
-uint64_t Instruction::ImmLogical() {
-  unsigned reg_size = SixtyFourBits() ? kXRegSize : kWRegSize;
-  int64_t n = BitN();
-  int64_t imm_s = ImmSetBits();
-  int64_t imm_r = ImmRotate();
-
-  // An integer is constructed from the n, imm_s and imm_r bits according to
-  // the following table:
-  //
-  //  N   imms    immr    size        S             R
-  //  1  ssssss  rrrrrr    64    UInt(ssssss)  UInt(rrrrrr)
-  //  0  0sssss  xrrrrr    32    UInt(sssss)   UInt(rrrrr)
-  //  0  10ssss  xxrrrr    16    UInt(ssss)    UInt(rrrr)
-  //  0  110sss  xxxrrr     8    UInt(sss)     UInt(rrr)
-  //  0  1110ss  xxxxrr     4    UInt(ss)      UInt(rr)
-  //  0  11110s  xxxxxr     2    UInt(s)       UInt(r)
-  // (s bits must not be all set)
-  //
-  // A pattern is constructed of size bits, where the least significant S+1
-  // bits are set. The pattern is rotated right by R, and repeated across a
-  // 32 or 64-bit value, depending on destination register width.
-  //
-
-  if (n == 1) {
-    if (imm_s == 0x3F) {
-      return 0;
-    }
-    uint64_t bits = (1UL << (imm_s + 1)) - 1;
-    return RotateRight(bits, imm_r, 64);
-  } else {
-    if ((imm_s >> 1) == 0x1F) {
-      return 0;
-    }
-    for (int width = 0x20; width >= 0x2; width >>= 1) {
-      if ((imm_s & width) == 0) {
-        int mask = width - 1;
-        if ((imm_s & mask) == mask) {
-          return 0;
-        }
-        uint64_t bits = (1UL << ((imm_s & mask) + 1)) - 1;
-        return RepeatBitsAcrossReg(reg_size,
-                                   RotateRight(bits, imm_r & mask, width),
-                                   width);
-      }
-    }
-  }
-  UNREACHABLE();
-  return 0;
-}
-
-
-float Instruction::ImmFP32() {
-  //  ImmFP: abcdefgh (8 bits)
-  // Single: aBbb.bbbc.defg.h000.0000.0000.0000.0000 (32 bits)
-  // where B is b ^ 1
-  uint32_t bits = ImmFP();
-  uint32_t bit7 = (bits >> 7) & 0x1;
-  uint32_t bit6 = (bits >> 6) & 0x1;
-  uint32_t bit5_to_0 = bits & 0x3f;
-  uint32_t result = (bit7 << 31) | ((32 - bit6) << 25) | (bit5_to_0 << 19);
-
-  return rawbits_to_float(result);
-}
-
-
-double Instruction::ImmFP64() {
-  //  ImmFP: abcdefgh (8 bits)
-  // Double: aBbb.bbbb.bbcd.efgh.0000.0000.0000.0000
-  //         0000.0000.0000.0000.0000.0000.0000.0000 (64 bits)
-  // where B is b ^ 1
-  uint32_t bits = ImmFP();
-  uint64_t bit7 = (bits >> 7) & 0x1;
-  uint64_t bit6 = (bits >> 6) & 0x1;
-  uint64_t bit5_to_0 = bits & 0x3f;
-  uint64_t result = (bit7 << 63) | ((256 - bit6) << 54) | (bit5_to_0 << 48);
-
-  return rawbits_to_double(result);
-}
-
-
-LSDataSize CalcLSPairDataSize(LoadStorePairOp op) {
-  switch (op) {
-    case STP_x:
-    case LDP_x:
-    case STP_d:
-    case LDP_d: return LSDoubleWord;
-    default: return LSWord;
-  }
-}
-
-
-ptrdiff_t Instruction::ImmPCOffset() {
-  ptrdiff_t offset;
-  if (IsPCRelAddressing()) {
-    // PC-relative addressing. Only ADR is supported.
-    offset = ImmPCRel();
-  } else if (BranchType() != UnknownBranchType) {
-    // All PC-relative branches.
-    // Relative branch offsets are instruction-size-aligned.
-    offset = ImmBranch() << kInstructionSizeLog2;
-  } else {
-    // Load literal (offset from PC).
-    ASSERT(IsLdrLiteral());
-    // The offset is always shifted by 2 bits, even for loads to 64-bits
-    // registers.
-    offset = ImmLLiteral() << kInstructionSizeLog2;
-  }
-  return offset;
-}
-
-
-Instruction* Instruction::ImmPCOffsetTarget() {
-  return this + ImmPCOffset();
-}
-
-
-bool Instruction::IsValidImmPCOffset(ImmBranchType branch_type,
-                                     int32_t offset) {
-  return is_intn(offset, ImmBranchRangeBitwidth(branch_type));
-}
-
-
-bool Instruction::IsTargetInImmPCOffsetRange(Instruction* target) {
-  int offset = target - this;
-  return IsValidImmPCOffset(BranchType(), offset);
-}
-
-
-void Instruction::SetImmPCOffsetTarget(Instruction* target) {
-  if (IsPCRelAddressing()) {
-    SetPCRelImmTarget(target);
-  } else if (BranchType() != UnknownBranchType) {
-    SetBranchImmTarget(target);
-  } else {
-    SetImmLLiteral(target);
-  }
-}
-
-
-void Instruction::SetPCRelImmTarget(Instruction* target) {
-  // ADRP is not supported, so 'this' must point to an ADR instruction.
-  ASSERT(Mask(PCRelAddressingMask) == ADR);
-
-  Instr imm = Assembler::ImmPCRelAddress(target - this);
-
-  SetInstructionBits(Mask(~ImmPCRel_mask) | imm);
-}
-
-
-void Instruction::SetBranchImmTarget(Instruction* target) {
-  ASSERT(((target - this) & 3) == 0);
-  Instr branch_imm = 0;
-  uint32_t imm_mask = 0;
-  int offset = (target - this) >> kInstructionSizeLog2;
-  switch (BranchType()) {
-    case CondBranchType: {
-      branch_imm = Assembler::ImmCondBranch(offset);
-      imm_mask = ImmCondBranch_mask;
-      break;
-    }
-    case UncondBranchType: {
-      branch_imm = Assembler::ImmUncondBranch(offset);
-      imm_mask = ImmUncondBranch_mask;
-      break;
-    }
-    case CompareBranchType: {
-      branch_imm = Assembler::ImmCmpBranch(offset);
-      imm_mask = ImmCmpBranch_mask;
-      break;
-    }
-    case TestBranchType: {
-      branch_imm = Assembler::ImmTestBranch(offset);
-      imm_mask = ImmTestBranch_mask;
-      break;
-    }
-    default: UNREACHABLE();
-  }
-  SetInstructionBits(Mask(~imm_mask) | branch_imm);
-}
-
-
-void Instruction::SetImmLLiteral(Instruction* source) {
-  ASSERT(((source - this) & 3) == 0);
-  int offset = (source - this) >> kLiteralEntrySizeLog2;
-  Instr imm = Assembler::ImmLLiteral(offset);
-  Instr mask = ImmLLiteral_mask;
-
-  SetInstructionBits(Mask(~mask) | imm);
-}
-
-
-// TODO(jbramley): We can't put this inline in the class because things like
-// xzr and Register are not defined in that header. Consider adding
-// instructions-a64-inl.h to work around this.
-bool InstructionSequence::IsInlineData() const {
-  // Inline data is encoded as a single movz instruction which writes to xzr
-  // (x31).
-  return IsMovz() && SixtyFourBits() && (Rd() == xzr.code());
-  // TODO(all): If we extend ::InlineData() to support bigger data, we need
-  // to update this method too.
-}
-
-
-// TODO(jbramley): We can't put this inline in the class because things like
-// xzr and Register are not defined in that header. Consider adding
-// instructions-a64-inl.h to work around this.
-uint64_t InstructionSequence::InlineData() const {
-  ASSERT(IsInlineData());
-  uint64_t payload = ImmMoveWide();
-  // TODO(all): If we extend ::InlineData() to support bigger data, we need
-  // to update this method too.
-  return payload;
-}
-
-
-} }  // namespace v8::internal
-
-#endif  // V8_TARGET_ARCH_A64