instruction-selector-s390.cc

Go to the documentation of this file.

// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
 
#include <optional>
 
#include "src/base/logging.h"
#include "src/compiler/backend/instruction-selector-adapter.h"
#include "src/compiler/backend/instruction-selector-impl.h"
#include "src/compiler/turboshaft/operations.h"
#include "src/compiler/turboshaft/opmasks.h"
#include "src/execution/frame-constants.h"
 
namespace v8 {
namespace internal {
namespace compiler {
 
using namespace turboshaft;  // NOLINT(build/namespaces)
 
enum class OperandMode : uint32_t {
  kNone = 0u,
  // Immediate mode
  kShift32Imm = 1u << 0,
  kShift64Imm = 1u << 1,
  kInt32Imm = 1u << 2,
  kInt32Imm_Negate = 1u << 3,
  kUint32Imm = 1u << 4,
  kInt20Imm = 1u << 5,
  kUint12Imm = 1u << 6,
  // Instr format
  kAllowRRR = 1u << 7,
  kAllowRM = 1u << 8,
  kAllowRI = 1u << 9,
  kAllowRRI = 1u << 10,
  kAllowRRM = 1u << 11,
  // Useful combination
  kAllowImmediate = kAllowRI | kAllowRRI,
  kAllowMemoryOperand = kAllowRM | kAllowRRM,
  kAllowDistinctOps = kAllowRRR | kAllowRRI | kAllowRRM,
  kBitWiseCommonMode = kAllowRI,
  kArithmeticCommonMode = kAllowRM | kAllowRI
};
 
using OperandModes = base::Flags<OperandMode, uint32_t>;
DEFINE_OPERATORS_FOR_FLAGS(OperandModes)
OperandModes immediateModeMask =
    OperandMode::kShift32Imm | OperandMode::kShift64Imm |
    OperandMode::kInt32Imm | OperandMode::kInt32Imm_Negate |
    OperandMode::kUint32Imm | OperandMode::kInt20Imm;
 
#define AndCommonMode                                                \
  ((OperandMode::kAllowRM |                                          \
    (CpuFeatures::IsSupported(DISTINCT_OPS) ? OperandMode::kAllowRRR \
                                            : OperandMode::kNone)))
#define And64OperandMode AndCommonMode
#define Or64OperandMode And64OperandMode
#define Xor64OperandMode And64OperandMode
 
#define And32OperandMode \
  (AndCommonMode | OperandMode::kAllowRI | OperandMode::kUint32Imm)
#define Or32OperandMode And32OperandMode
#define Xor32OperandMode And32OperandMode
 
#define Shift32OperandMode                                   \
  ((OperandMode::kAllowRI | OperandMode::kShift64Imm |       \
    (CpuFeatures::IsSupported(DISTINCT_OPS)                  \
         ? (OperandMode::kAllowRRR | OperandMode::kAllowRRI) \
         : OperandMode::kNone)))
 
#define Shift64OperandMode                             \
  ((OperandMode::kAllowRI | OperandMode::kShift64Imm | \
    OperandMode::kAllowRRR | OperandMode::kAllowRRI))
 
#define AddOperandMode                                            \
  ((OperandMode::kArithmeticCommonMode | OperandMode::kInt32Imm | \
    (CpuFeatures::IsSupported(DISTINCT_OPS)                       \
         ? (OperandMode::kAllowRRR | OperandMode::kAllowRRI)      \
         : OperandMode::kArithmeticCommonMode)))
#define SubOperandMode                                                   \
  ((OperandMode::kArithmeticCommonMode | OperandMode::kInt32Imm_Negate | \
    (CpuFeatures::IsSupported(DISTINCT_OPS)                              \
         ? (OperandMode::kAllowRRR | OperandMode::kAllowRRI)             \
         : OperandMode::kArithmeticCommonMode)))
#define MulOperandMode \
  (OperandMode::kArithmeticCommonMode | OperandMode::kInt32Imm)
 
struct BaseWithScaledIndexAndDisplacementMatch {
  OpIndex base = {};
  OpIndex index = {};
  int scale = 0;
  int64_t displacement = 0;
  DisplacementMode displacement_mode = kPositiveDisplacement;
};
 
std::optional<BaseWithScaledIndexAndDisplacementMatch>
TryMatchBaseWithScaledIndexAndDisplacement64(InstructionSelectorT* selector,
                                             OpIndex node) {
  // The BaseWithIndexAndDisplacementMatcher canonicalizes the order of
  // displacements and scale factors that are used as inputs, so instead of
  // enumerating all possible patterns by brute force, checking for node
  // clusters using the following templates in the following order suffices
  // to find all of the interesting cases (S = index * scale, B = base
  // input, D = displacement input):
  //
  // (S + (B + D))
  // (S + (B + B))
  // (S + D)
  // (S + B)
  // ((S + D) + B)
  // ((S + B) + D)
  // ((B + D) + B)
  // ((B + B) + D)
  // (B + D)
  // (B + B)
  BaseWithScaledIndexAndDisplacementMatch result;
  result.displacement_mode = kPositiveDisplacement;
 
  const Operation& op = selector->Get(node);
  if (const LoadOp* load = op.TryCast<LoadOp>()) {
    result.base = load->base();
    result.index = load->index().value_or_invalid();
    result.scale = load->element_size_log2;
    result.displacement = load->offset;
    if (load->kind.tagged_base) result.displacement -= kHeapObjectTag;
    return result;
  } else if (const StoreOp* store = op.TryCast<StoreOp>()) {
    result.base = store->base();
    result.index = store->index().value_or_invalid();
    result.scale = store->element_size_log2;
    result.displacement = store->offset;
    if (store->kind.tagged_base) result.displacement -= kHeapObjectTag;
    return result;
  } else if (op.Is<WordBinopOp>()) {
    UNIMPLEMENTED();
#ifdef V8_ENABLE_WEBASSEMBLY
  } else if (const Simd128LaneMemoryOp* lane_op =
                 op.TryCast<Simd128LaneMemoryOp>()) {
    result.base = lane_op->base();
    result.index = lane_op->index();
    result.scale = 0;
    result.displacement = 0;
    if (lane_op->kind.tagged_base) result.displacement -= kHeapObjectTag;
    return result;
  } else if (const Simd128LoadTransformOp* load_transform =
                 op.TryCast<Simd128LoadTransformOp>()) {
    result.base = load_transform->base();
    result.index = load_transform->index();
    DCHECK_EQ(load_transform->offset, 0);
    result.scale = 0;
    result.displacement = 0;
    DCHECK(!load_transform->load_kind.tagged_base);
    return result;
#endif  // V8_ENABLE_WEBASSEMBLY
  }
  return std::nullopt;
}
 
// Adds S390-specific methods for generating operands.
class S390OperandGeneratorT final : public OperandGeneratorT {
 public:
  explicit S390OperandGeneratorT(InstructionSelectorT* selector)
      : OperandGeneratorT(selector) {}
 
  InstructionOperand UseOperand(OpIndex node, OperandModes mode) {
    if (CanBeImmediate(node, mode)) {
      return UseImmediate(node);
    }
    return UseRegister(node);
  }
 
  InstructionOperand UseAnyExceptImmediate(OpIndex node) {
    int64_t value;
    if (MatchSignedIntegralConstant(node, &value))
      return UseRegister(node);
    else
      return this->Use(node);
  }
 
  int64_t GetImmediate(OpIndex node) {
    ConstantOp* op =
        this->turboshaft_graph()->Get(node).template TryCast<ConstantOp>();
    switch (op->kind) {
      case ConstantOp::Kind::kWord32:
        return op->word32();
      case ConstantOp::Kind::kWord64:
        return op->word64();
      default:
        UNIMPLEMENTED();
    }
  }
 
  bool CanBeImmediate(OpIndex node, OperandModes mode) {
    int64_t value;
    if (!selector()->MatchSignedIntegralConstant(node, &value)) return false;
    return CanBeImmediate(value, mode);
  }
 
  bool CanBeImmediate(int64_t value, OperandModes mode) {
    if (mode & OperandMode::kShift32Imm)
      return 0 <= value && value < 32;
    else if (mode & OperandMode::kShift64Imm)
      return 0 <= value && value < 64;
    else if (mode & OperandMode::kInt32Imm)
      return is_int32(value);
    else if (mode & OperandMode::kInt32Imm_Negate)
      return is_int32(-value);
    else if (mode & OperandMode::kUint32Imm)
      return is_uint32(value);
    else if (mode & OperandMode::kInt20Imm)
      return is_int20(value);
    else if (mode & OperandMode::kUint12Imm)
      return is_uint12(value);
    else
      return false;
  }
 
  bool CanBeMemoryOperand(InstructionCode opcode, OpIndex user, OpIndex input,
                          int effect_level) {
    if (!this->IsLoadOrLoadImmutable(input)) return false;
    if (!selector()->CanCover(user, input)) return false;
    if (effect_level != selector()->GetEffectLevel(input)) {
      return false;
    }
 
    MachineRepresentation rep =
        this->load_view(input).loaded_rep().representation();
    switch (opcode) {
      case kS390_Cmp64:
      case kS390_LoadAndTestWord64:
        if (rep == MachineRepresentation::kWord64 ||
            (!COMPRESS_POINTERS_BOOL && IsAnyTagged(rep))) {
          DCHECK_EQ(ElementSizeInBits(rep), 64);
          return true;
        }
        break;
      case kS390_LoadAndTestWord32:
      case kS390_Cmp32:
        if (rep == MachineRepresentation::kWord32 ||
            (COMPRESS_POINTERS_BOOL && IsAnyCompressed(rep))) {
          DCHECK_EQ(ElementSizeInBits(rep), 32);
          return true;
        }
        break;
      default:
        break;
    }
    return false;
  }
 
  AddressingMode GenerateMemoryOperandInputs(
      OptionalOpIndex index, OpIndex base, int64_t displacement,
      DisplacementMode displacement_mode, InstructionOperand inputs[],
      size_t* input_count,
      RegisterUseKind reg_kind = RegisterUseKind::kUseRegister) {
    AddressingMode mode = kMode_MRI;
    if (base.valid()) {
      inputs[(*input_count)++] = UseRegister(base, reg_kind);
      if (index.valid()) {
        inputs[(*input_count)++] = UseRegister(this->value(index), reg_kind);
        if (displacement != 0) {
          inputs[(*input_count)++] = UseImmediate(
              displacement_mode == kNegativeDisplacement ? -displacement
                                                         : displacement);
          mode = kMode_MRRI;
        } else {
          mode = kMode_MRR;
        }
      } else {
        if (displacement == 0) {
          mode = kMode_MR;
        } else {
          inputs[(*input_count)++] = UseImmediate(
              displacement_mode == kNegativeDisplacement ? -displacement
                                                         : displacement);
          mode = kMode_MRI;
        }
      }
    } else {
      DCHECK(index.valid());
      inputs[(*input_count)++] = UseRegister(this->value(index), reg_kind);
      if (displacement != 0) {
        inputs[(*input_count)++] = UseImmediate(
            displacement_mode == kNegativeDisplacement ? -displacement
                                                       : displacement);
        mode = kMode_MRI;
      } else {
        mode = kMode_MR;
      }
    }
    return mode;
  }
 
  AddressingMode GetEffectiveAddressMemoryOperand(
      OpIndex operand, InstructionOperand inputs[], size_t* input_count,
      OperandModes immediate_mode = OperandMode::kInt20Imm) {
    auto m = TryMatchBaseWithScaledIndexAndDisplacement64(selector(), operand);
    DCHECK(m.has_value());
    if (m->base.valid() &&
        this->Get(m->base).template Is<LoadRootRegisterOp>()) {
      DCHECK(!m->index.valid());
      DCHECK_EQ(m->scale, 0);
      inputs[(*input_count)++] =
          UseImmediate(static_cast<int>(m->displacement));
      return kMode_Root;
    } else if (CanBeImmediate(m->displacement, immediate_mode)) {
      DCHECK_EQ(m->scale, 0);
      return GenerateMemoryOperandInputs(m->index, m->base, m->displacement,
                                         m->displacement_mode, inputs,
                                         input_count);
    } else {
      DCHECK_EQ(m->displacement, 0);
      inputs[(*input_count)++] = UseRegister(m->base);
      inputs[(*input_count)++] = UseRegister(m->index);
      return kMode_MRR;
    }
  }
 
  bool CanBeBetterLeftOperand(OpIndex node) const {
    return !selector()->IsLive(node);
  }
};
 
namespace {
 
bool S390OpcodeOnlySupport12BitDisp(ArchOpcode opcode) {
  switch (opcode) {
    case kS390_AddFloat:
    case kS390_AddDouble:
    case kS390_CmpFloat:
    case kS390_CmpDouble:
    case kS390_Float32ToDouble:
      return true;
    default:
      return false;
  }
}
 
bool S390OpcodeOnlySupport12BitDisp(InstructionCode op) {
  ArchOpcode opcode = ArchOpcodeField::decode(op);
  return S390OpcodeOnlySupport12BitDisp(opcode);
}
 
#define OpcodeImmMode(op)                                       \
  (S390OpcodeOnlySupport12BitDisp(op) ? OperandMode::kUint12Imm \
                                      : OperandMode::kInt20Imm)
 
ArchOpcode SelectLoadOpcode(MemoryRepresentation loaded_rep,
                            RegisterRepresentation result_rep) {
  // NOTE: The meaning of `loaded_rep` = `MemoryRepresentation::AnyTagged()` is
  // we are loading a compressed tagged field, while `result_rep` =
  // `RegisterRepresentation::Tagged()` refers to an uncompressed tagged value.
  switch (loaded_rep) {
    case MemoryRepresentation::Int8():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word32());
      return kS390_LoadWordS8;
    case MemoryRepresentation::Uint8():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word32());
      return kS390_LoadWordU8;
    case MemoryRepresentation::Int16():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word32());
      return kS390_LoadWordS16;
    case MemoryRepresentation::Uint16():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word32());
      return kS390_LoadWordU16;
    case MemoryRepresentation::Int32():
    case MemoryRepresentation::Uint32():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word32());
      return kS390_LoadWordU32;
    case MemoryRepresentation::Int64():
    case MemoryRepresentation::Uint64():
      DCHECK_EQ(result_rep, RegisterRepresentation::Word64());
      return kS390_LoadWord64;
    case MemoryRepresentation::Float16():
      UNIMPLEMENTED();
    case MemoryRepresentation::Float32():
      DCHECK_EQ(result_rep, RegisterRepresentation::Float32());
      return kS390_LoadFloat32;
    case MemoryRepresentation::Float64():
      DCHECK_EQ(result_rep, RegisterRepresentation::Float64());
      return kS390_LoadDouble;
#ifdef V8_COMPRESS_POINTERS
    case MemoryRepresentation::AnyTagged():
    case MemoryRepresentation::TaggedPointer():
      if (result_rep == RegisterRepresentation::Compressed()) {
        return kS390_LoadWordS32;
      }
      DCHECK_EQ(result_rep, RegisterRepresentation::Tagged());
      return kS390_LoadDecompressTagged;
    case MemoryRepresentation::TaggedSigned():
      if (result_rep == RegisterRepresentation::Compressed()) {
        return kS390_LoadWordS32;
      }
      DCHECK_EQ(result_rep, RegisterRepresentation::Tagged());
      return kS390_LoadDecompressTaggedSigned;
#else
    case MemoryRepresentation::AnyTagged():
    case MemoryRepresentation::TaggedPointer():
    case MemoryRepresentation::TaggedSigned():
      DCHECK_EQ(result_rep, RegisterRepresentation::Tagged());
      return kS390_LoadWord64;
#endif
    case MemoryRepresentation::AnyUncompressedTagged():
    case MemoryRepresentation::UncompressedTaggedPointer():
    case MemoryRepresentation::UncompressedTaggedSigned():
      DCHECK_EQ(result_rep, RegisterRepresentation::Tagged());
      return kS390_LoadWord64;
    case MemoryRepresentation::Simd128():
      DCHECK_EQ(result_rep, RegisterRepresentation::Simd128());
      return kS390_LoadSimd128;
    case MemoryRepresentation::ProtectedPointer():
    case MemoryRepresentation::IndirectPointer():
    case MemoryRepresentation::SandboxedPointer():
    case MemoryRepresentation::Simd256():
      UNREACHABLE();
  }
}
 
ArchOpcode SelectLoadOpcode(LoadRepresentation load_rep) {
  ArchOpcode opcode;
  switch (load_rep.representation()) {
    case MachineRepresentation::kFloat32:
      opcode = kS390_LoadFloat32;
      break;
    case MachineRepresentation::kFloat64:
      opcode = kS390_LoadDouble;
      break;
    case MachineRepresentation::kBit:  // Fall through.
    case MachineRepresentation::kWord8:
      opcode = load_rep.IsSigned() ? kS390_LoadWordS8 : kS390_LoadWordU8;
      break;
    case MachineRepresentation::kWord16:
      opcode = load_rep.IsSigned() ? kS390_LoadWordS16 : kS390_LoadWordU16;
      break;
    case MachineRepresentation::kWord32:
      opcode = kS390_LoadWordU32;
      break;
    case MachineRepresentation::kCompressedPointer:  // Fall through.
    case MachineRepresentation::kCompressed:
    case MachineRepresentation::kIndirectPointer:  // Fall through.
    case MachineRepresentation::kSandboxedPointer:  // Fall through.
#ifdef V8_COMPRESS_POINTERS
      opcode = kS390_LoadWordS32;
      break;
#else
      UNREACHABLE();
#endif
#ifdef V8_COMPRESS_POINTERS
    case MachineRepresentation::kTaggedSigned:
      opcode = kS390_LoadDecompressTaggedSigned;
      break;
    case MachineRepresentation::kTaggedPointer:
      opcode = kS390_LoadDecompressTagged;
      break;
    case MachineRepresentation::kTagged:
      opcode = kS390_LoadDecompressTagged;
      break;
#else
    case MachineRepresentation::kTaggedSigned:   // Fall through.
    case MachineRepresentation::kTaggedPointer:  // Fall through.
    case MachineRepresentation::kTagged:         // Fall through.
#endif
    case MachineRepresentation::kWord64:
      opcode = kS390_LoadWord64;
      break;
    case MachineRepresentation::kSimd128:
      opcode = kS390_LoadSimd128;
      break;
    case MachineRepresentation::kFloat16:
      UNIMPLEMENTED();
    case MachineRepresentation::kProtectedPointer:  // Fall through.
    case MachineRepresentation::kSimd256:  // Fall through.
    case MachineRepresentation::kMapWord:  // Fall through.
    case MachineRepresentation::kFloat16RawBits:  // Fall through.
    case MachineRepresentation::kNone:
    default:
      UNREACHABLE();
  }
  return opcode;
}
 
#define RESULT_IS_WORD32_LIST(V)   \
  /* Float unary op*/              \
  V(BitcastFloat32ToInt32)         \
  /* V(TruncateFloat64ToWord32) */ \
  V(RoundFloat64ToInt32)           \
  V(TruncateFloat32ToInt32)        \
  V(TruncateFloat32ToUint32)       \
  V(TruncateFloat64ToUint32)       \
  V(ChangeFloat64ToInt32)          \
  V(ChangeFloat64ToUint32)         \
  /* Word32 unary op */            \
  V(Word32Clz)                     \
  V(Word32Popcnt)                  \
  V(Float64ExtractLowWord32)       \
  V(Float64ExtractHighWord32)      \
  V(SignExtendWord8ToInt32)        \
  V(SignExtendWord16ToInt32)       \
  /* Word32 bin op */              \
  V(Int32Add)                      \
  V(Int32Sub)                      \
  V(Int32Mul)                      \
  V(Int32AddWithOverflow)          \
  V(Int32SubWithOverflow)          \
  V(Int32MulWithOverflow)          \
  V(Int32MulHigh)                  \
  V(Uint32MulHigh)                 \
  V(Int32Div)                      \
  V(Uint32Div)                     \
  V(Int32Mod)                      \
  V(Uint32Mod)                     \
  V(Word32Ror)                     \
  V(Word32And)                     \
  V(Word32Or)                      \
  V(Word32Xor)                     \
  V(Word32Shl)                     \
  V(Word32Shr)                     \
  V(Word32Sar)
 
bool ProduceWord32Result(InstructionSelectorT* selector, OpIndex node) {
  const Operation& op = selector->Get(node);
  switch (op.opcode) {
    case Opcode::kWordBinop: {
      const auto& binop = op.Cast<WordBinopOp>();
      if (binop.rep != WordRepresentation::Word32()) return false;
      return binop.kind == WordBinopOp::Kind::kAdd ||
             binop.kind == WordBinopOp::Kind::kSub ||
             binop.kind == WordBinopOp::Kind::kMul ||
             binop.kind == WordBinopOp::Kind::kSignedDiv ||
             binop.kind == WordBinopOp::Kind::kUnsignedDiv ||
             binop.kind == WordBinopOp::Kind::kSignedMod ||
             binop.kind == WordBinopOp::Kind::kUnsignedMod ||
             binop.kind == WordBinopOp::Kind::kBitwiseAnd ||
             binop.kind == WordBinopOp::Kind::kBitwiseOr ||
             binop.kind == WordBinopOp::Kind::kBitwiseXor ||
             binop.kind == WordBinopOp::Kind::kSignedMulOverflownBits ||
             binop.kind == WordBinopOp::Kind::kUnsignedMulOverflownBits;
    }
    case Opcode::kWordUnary: {
      const auto& unop = op.Cast<WordUnaryOp>();
      if (unop.rep != WordRepresentation::Word32()) return false;
      return unop.kind == WordUnaryOp::Kind::kCountLeadingZeros ||
             unop.kind == WordUnaryOp::Kind::kPopCount ||
             unop.kind == WordUnaryOp::Kind::kSignExtend8 ||
             unop.kind == WordUnaryOp::Kind::kSignExtend16;
    }
    case Opcode::kChange: {
      const auto& changeop = op.Cast<ChangeOp>();
      switch (changeop.kind) {
        // Float64ExtractLowWord32
        // Float64ExtractHighWord32
        case ChangeOp::Kind::kExtractLowHalf:
        case ChangeOp::Kind::kExtractHighHalf:
          CHECK_EQ(changeop.from, FloatRepresentation::Float64());
          CHECK_EQ(changeop.to, WordRepresentation::Word32());
          return true;
        // BitcastFloat32ToInt32
        case ChangeOp::Kind::kBitcast:
          return changeop.from == FloatRepresentation::Float32() &&
                 changeop.to == WordRepresentation::Word32();
        case ChangeOp::Kind::kSignedFloatTruncateOverflowToMin:
        case ChangeOp::Kind::kUnsignedFloatTruncateOverflowToMin:
          // RoundFloat64ToInt32
          // ChangeFloat64ToInt32
          // TruncateFloat64ToUint32
          // ChangeFloat64ToUint32
          if (changeop.from == FloatRepresentation::Float64() &&
              changeop.to == WordRepresentation::Word32()) {
            return true;
          }
          // TruncateFloat32ToInt32
          // TruncateFloat32ToUint32
          if (changeop.from == FloatRepresentation::Float32() &&
              changeop.to == WordRepresentation::Word32()) {
            return true;
          }
          return false;
        default:
          return false;
      }
    }
    case Opcode::kShift: {
      const auto& shift = op.Cast<ShiftOp>();
      if (shift.rep != WordRepresentation::Word32()) return false;
      return shift.kind == ShiftOp::Kind::kShiftRightArithmetic ||
             shift.kind == ShiftOp::Kind::kShiftRightLogical ||
             shift.kind == ShiftOp::Kind::kShiftRightArithmeticShiftOutZeros ||
             shift.kind == ShiftOp::Kind::kShiftLeft ||
             shift.kind == ShiftOp::Kind::kRotateRight;
    }
    case Opcode::kOverflowCheckedBinop: {
      const auto& ovfbinop = op.Cast<OverflowCheckedBinopOp>();
      if (ovfbinop.rep != WordRepresentation::Word32()) return false;
      return ovfbinop.kind == OverflowCheckedBinopOp::Kind::kSignedAdd ||
             ovfbinop.kind == OverflowCheckedBinopOp::Kind::kSignedSub ||
             ovfbinop.kind == OverflowCheckedBinopOp::Kind::kSignedMul;
    }
    case Opcode::kLoad: {
      LoadRepresentation load_rep = selector->load_view(node).loaded_rep();
      MachineRepresentation rep = load_rep.representation();
      switch (rep) {
        case MachineRepresentation::kWord32:
          return true;
        case MachineRepresentation::kWord8:
          if (load_rep.IsSigned())
            return false;
          else
            return true;
        default:
          return false;
      }
    }
    default:
      return false;
  }
}
 
static inline bool DoZeroExtForResult(InstructionSelectorT* selector,
                                      OpIndex node) {
  return ProduceWord32Result(selector, node);
}
 
// TODO(john.yan): Create VisiteShift to match dst = src shift (R+I)
#if 0
void VisitShift() { }
#endif
 
void VisitTryTruncateDouble(InstructionSelectorT* selector, ArchOpcode opcode,
                            OpIndex node) {
  S390OperandGeneratorT g(selector);
  InstructionOperand inputs[] = {g.UseRegister(selector->input_at(node, 0))};
  InstructionOperand outputs[2];
  size_t output_count = 0;
  outputs[output_count++] = g.DefineAsRegister(node);
 
  OptionalOpIndex success_output = selector->FindProjection(node, 1);
  if (success_output.valid()) {
    outputs[output_count++] = g.DefineAsRegister(success_output.value());
  }
 
  selector->Emit(opcode, output_count, outputs, 1, inputs);
}
 
template <class CanCombineWithLoad>
void GenerateRightOperands(InstructionSelectorT* selector, OpIndex node,
                           OpIndex right, InstructionCode* opcode,
                           OperandModes* operand_mode,
                           InstructionOperand* inputs, size_t* input_count,
                           CanCombineWithLoad canCombineWithLoad) {
  S390OperandGeneratorT g(selector);
 
  if ((*operand_mode & OperandMode::kAllowImmediate) &&
      g.CanBeImmediate(right, *operand_mode)) {
    inputs[(*input_count)++] = g.UseImmediate(right);
    // Can only be RI or RRI
    *operand_mode &= OperandMode::kAllowImmediate;
  } else if (*operand_mode & OperandMode::kAllowMemoryOperand) {
    const Operation& right_op = selector->Get(right);
    if (right_op.Is<LoadOp>() && selector->CanCover(node, right) &&
        canCombineWithLoad(
            SelectLoadOpcode(selector->load_view(right).ts_loaded_rep(),
                             selector->load_view(right).ts_result_rep()))) {
      AddressingMode mode =
          g.GetEffectiveAddressMemoryOperand(right, inputs, input_count);
      *opcode |= AddressingModeField::encode(mode);
      *operand_mode &= ~OperandMode::kAllowImmediate;
      if (*operand_mode & OperandMode::kAllowRM)
        *operand_mode &= ~OperandMode::kAllowDistinctOps;
    } else if (*operand_mode & OperandMode::kAllowRM) {
      DCHECK(!(*operand_mode & OperandMode::kAllowRRM));
      inputs[(*input_count)++] = g.UseAnyExceptImmediate(right);
      // Can not be Immediate
      *operand_mode &=
          ~OperandMode::kAllowImmediate & ~OperandMode::kAllowDistinctOps;
    } else if (*operand_mode & OperandMode::kAllowRRM) {
      DCHECK(!(*operand_mode & OperandMode::kAllowRM));
      inputs[(*input_count)++] = g.UseAnyExceptImmediate(right);
      // Can not be Immediate
      *operand_mode &= ~OperandMode::kAllowImmediate;
    } else {
      UNREACHABLE();
    }
  } else {
    inputs[(*input_count)++] = g.UseRegister(right);
    // Can only be RR or RRR
    *operand_mode &= OperandMode::kAllowRRR;
  }
}
 
template <class CanCombineWithLoad>
void GenerateBinOpOperands(InstructionSelectorT* selector, OpIndex node,
                           OpIndex left, OpIndex right, InstructionCode* opcode,
                           OperandModes* operand_mode,
                           InstructionOperand* inputs, size_t* input_count,
                           CanCombineWithLoad canCombineWithLoad) {
  S390OperandGeneratorT g(selector);
  // left is always register
  InstructionOperand const left_input = g.UseRegister(left);
  inputs[(*input_count)++] = left_input;
 
  if (left == right) {
    inputs[(*input_count)++] = left_input;
    // Can only be RR or RRR
    *operand_mode &= OperandMode::kAllowRRR;
  } else {
    GenerateRightOperands(selector, node, right, opcode, operand_mode, inputs,
                          input_count, canCombineWithLoad);
  }
}
 
template <class CanCombineWithLoad>
void VisitUnaryOp(InstructionSelectorT* selector, OpIndex node,
                  InstructionCode opcode, OperandModes operand_mode,
                  FlagsContinuationT* cont,
                  CanCombineWithLoad canCombineWithLoad);
 
template <class CanCombineWithLoad>
void VisitBinOp(InstructionSelectorT* selector, OpIndex node,
                InstructionCode opcode, OperandModes operand_mode,
                FlagsContinuationT* cont,
                CanCombineWithLoad canCombineWithLoad);
 
// Generate The following variations:
//   VisitWord32UnaryOp, VisitWord32BinOp,
//   VisitWord64UnaryOp, VisitWord64BinOp,
//   VisitFloat32UnaryOp, VisitFloat32BinOp,
//   VisitFloat64UnaryOp, VisitFloat64BinOp
#define VISIT_OP_LIST_32(V)                                            \
  V(Word32, Unary, [](ArchOpcode opcode) {                             \
    return opcode == kS390_LoadWordS32 || opcode == kS390_LoadWordU32; \
  })                                                                   \
  V(Word64, Unary,                                                     \
    [](ArchOpcode opcode) { return opcode == kS390_LoadWord64; })      \
  V(Float32, Unary,                                                    \
    [](ArchOpcode opcode) { return opcode == kS390_LoadFloat32; })     \
  V(Float64, Unary,                                                    \
    [](ArchOpcode opcode) { return opcode == kS390_LoadDouble; })      \
  V(Word32, Bin, [](ArchOpcode opcode) {                               \
    return opcode == kS390_LoadWordS32 || opcode == kS390_LoadWordU32; \
  })                                                                   \
  V(Float32, Bin,                                                      \
    [](ArchOpcode opcode) { return opcode == kS390_LoadFloat32; })     \
  V(Float64, Bin, [](ArchOpcode opcode) { return opcode == kS390_LoadDouble; })
 
#define VISIT_OP_LIST(V) \
  VISIT_OP_LIST_32(V)    \
  V(Word64, Bin, [](ArchOpcode opcode) { return opcode == kS390_LoadWord64; })
 
#define DECLARE_VISIT_HELPER_FUNCTIONS(type1, type2, canCombineWithLoad)    \
  static inline void Visit##type1##type2##Op(                               \
      InstructionSelectorT* selector, OpIndex node, InstructionCode opcode, \
      OperandModes operand_mode, FlagsContinuationT* cont) {                \
    Visit##type2##Op(selector, node, opcode, operand_mode, cont,            \
                     canCombineWithLoad);                                   \
  }                                                                         \
  static inline void Visit##type1##type2##Op(                               \
      InstructionSelectorT* selector, OpIndex node, InstructionCode opcode, \
      OperandModes operand_mode) {                                          \
    FlagsContinuationT cont;                                                \
    Visit##type1##type2##Op(selector, node, opcode, operand_mode, &cont);   \
  }
VISIT_OP_LIST(DECLARE_VISIT_HELPER_FUNCTIONS)
#undef DECLARE_VISIT_HELPER_FUNCTIONS
#undef VISIT_OP_LIST_32
#undef VISIT_OP_LIST
 
template <class CanCombineWithLoad>
void VisitUnaryOp(InstructionSelectorT* selector, OpIndex node,
                  InstructionCode opcode, OperandModes operand_mode,
                  FlagsContinuationT* cont,
                  CanCombineWithLoad canCombineWithLoad) {
  S390OperandGeneratorT g(selector);
  InstructionOperand inputs[8];
  size_t input_count = 0;
  InstructionOperand outputs[2];
  size_t output_count = 0;
  OpIndex input = selector->input_at(node, 0);
 
  GenerateRightOperands(selector, node, input, &opcode, &operand_mode, inputs,
                        &input_count, canCombineWithLoad);
 
  bool input_is_word32 = ProduceWord32Result(selector, input);
 
  bool doZeroExt = DoZeroExtForResult(selector, node);
  bool canEliminateZeroExt = input_is_word32;
 
  if (doZeroExt) {
    // Add zero-ext indication
    inputs[input_count++] = g.TempImmediate(!canEliminateZeroExt);
  }
 
  if (!cont->IsDeoptimize()) {
    // If we can deoptimize as a result of the binop, we need to make sure
    // that the deopt inputs are not overwritten by the binop result. One way
    // to achieve that is to declare the output register as same-as-first.
    if (doZeroExt && canEliminateZeroExt) {
      // we have to make sure result and left use the same register
      outputs[output_count++] = g.DefineSameAsFirst(node);
    } else {
      outputs[output_count++] = g.DefineAsRegister(node);
    }
  } else {
    outputs[output_count++] = g.DefineSameAsFirst(node);
  }
 
  DCHECK_NE(0u, input_count);
  DCHECK_NE(0u, output_count);
  DCHECK_GE(arraysize(inputs), input_count);
  DCHECK_GE(arraysize(outputs), output_count);
 
  selector->EmitWithContinuation(opcode, output_count, outputs, input_count,
                                 inputs, cont);
}
 
template <class CanCombineWithLoad>
void VisitBinOp(InstructionSelectorT* selector, OpIndex node,
                InstructionCode opcode, OperandModes operand_mode,
                FlagsContinuationT* cont,
                CanCombineWithLoad canCombineWithLoad) {
  S390OperandGeneratorT g(selector);
  OpIndex left = selector->input_at(node, 0);
  OpIndex right = selector->input_at(node, 1);
  InstructionOperand inputs[8];
  size_t input_count = 0;
  InstructionOperand outputs[2];
  size_t output_count = 0;
 
    const Operation& op = selector->Get(node);
    if (op.TryCast<WordBinopOp>() &&
        WordBinopOp::IsCommutative(
            selector->Get(node).template Cast<WordBinopOp>().kind) &&
        !g.CanBeImmediate(right, operand_mode) &&
        (g.CanBeBetterLeftOperand(right))) {
      std::swap(left, right);
    }
 
  GenerateBinOpOperands(selector, node, left, right, &opcode, &operand_mode,
                        inputs, &input_count, canCombineWithLoad);
 
  bool left_is_word32 = ProduceWord32Result(selector, left);
 
  bool doZeroExt = DoZeroExtForResult(selector, node);
  bool canEliminateZeroExt = left_is_word32;
 
  if (doZeroExt) {
    // Add zero-ext indication
    inputs[input_count++] = g.TempImmediate(!canEliminateZeroExt);
  }
 
  if ((operand_mode & OperandMode::kAllowDistinctOps) &&
      // If we can deoptimize as a result of the binop, we need to make sure
      // that the deopt inputs are not overwritten by the binop result. One way
      // to achieve that is to declare the output register as same-as-first.
      !cont->IsDeoptimize()) {
    if (doZeroExt && canEliminateZeroExt) {
      // we have to make sure result and left use the same register
      outputs[output_count++] = g.DefineSameAsFirst(node);
    } else {
      outputs[output_count++] = g.DefineAsRegister(node);
    }
  } else {
    outputs[output_count++] = g.DefineSameAsFirst(node);
  }
 
  DCHECK_NE(0u, input_count);
  DCHECK_NE(0u, output_count);
  DCHECK_GE(arraysize(inputs), input_count);
  DCHECK_GE(arraysize(outputs), output_count);
 
  selector->EmitWithContinuation(opcode, output_count, outputs, input_count,
                                 inputs, cont);
}
 
}  // namespace
 
void InstructionSelectorT::VisitStackSlot(OpIndex node) {
  const StackSlotOp& stack_slot = Cast<StackSlotOp>(node);
  int slot = frame_->AllocateSpillSlot(stack_slot.size, stack_slot.alignment,
                                       stack_slot.is_tagged);
  OperandGenerator g(this);
 
  Emit(kArchStackSlot, g.DefineAsRegister(node),
       sequence()->AddImmediate(Constant(slot)), 0, nullptr);
}
 
void InstructionSelectorT::VisitAbortCSADcheck(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kArchAbortCSADcheck, g.NoOutput(),
       g.UseFixed(this->input_at(node, 0), r3));
}
 
void InstructionSelectorT::VisitLoad(OpIndex node, OpIndex value,
                                     InstructionCode opcode) {
  S390OperandGeneratorT g(this);
  InstructionOperand outputs[] = {g.DefineAsRegister(node)};
  InstructionOperand inputs[3];
  size_t input_count = 0;
  AddressingMode mode =
      g.GetEffectiveAddressMemoryOperand(value, inputs, &input_count);
  opcode |= AddressingModeField::encode(mode);
  Emit(opcode, 1, outputs, input_count, inputs);
}
 
void InstructionSelectorT::VisitLoad(OpIndex node) {
  TurboshaftAdapter::LoadView view = this->load_view(node);
  VisitLoad(node, node,
            SelectLoadOpcode(view.ts_loaded_rep(), view.ts_result_rep()));
}
 
void InstructionSelectorT::VisitProtectedLoad(OpIndex node) {
  // TODO(eholk)
  UNIMPLEMENTED();
}
 
static void VisitGeneralStore(
    InstructionSelectorT* selector, OpIndex node, MachineRepresentation rep,
    WriteBarrierKind write_barrier_kind = kNoWriteBarrier) {
  S390OperandGeneratorT g(selector);
 
  auto store_view = selector->store_view(node);
  DCHECK_EQ(store_view.element_size_log2(), 0);
 
  OpIndex base = store_view.base();
  OptionalOpIndex index = store_view.index();
  OpIndex value = store_view.value();
  int32_t displacement = store_view.displacement();
 
  if (write_barrier_kind != kNoWriteBarrier &&
      !v8_flags.disable_write_barriers) {
    DCHECK(CanBeTaggedOrCompressedPointer(rep));
    // Uncompressed stores should not happen if we need a write barrier.
    CHECK((store_view.ts_stored_rep() !=
           MemoryRepresentation::AnyUncompressedTagged()) &&
          (store_view.ts_stored_rep() !=
           MemoryRepresentation::UncompressedTaggedPointer()) &&
          (store_view.ts_stored_rep() !=
           MemoryRepresentation::UncompressedTaggedPointer()));
    AddressingMode addressing_mode;
    InstructionOperand inputs[4];
    size_t input_count = 0;
    addressing_mode = g.GenerateMemoryOperandInputs(
        index, base, displacement, DisplacementMode::kPositiveDisplacement,
        inputs, &input_count,
        S390OperandGeneratorT::RegisterUseKind::kUseUniqueRegister);
    DCHECK_LT(input_count, 4);
    inputs[input_count++] = g.UseUniqueRegister(value);
    RecordWriteMode record_write_mode =
        WriteBarrierKindToRecordWriteMode(write_barrier_kind);
    InstructionOperand temps[] = {g.TempRegister(), g.TempRegister()};
    size_t const temp_count = arraysize(temps);
    InstructionCode code = kArchStoreWithWriteBarrier;
    code |= AddressingModeField::encode(addressing_mode);
    code |= RecordWriteModeField::encode(record_write_mode);
    selector->Emit(code, 0, nullptr, input_count, inputs, temp_count, temps);
  } else {
    ArchOpcode opcode;
 
    switch (store_view.ts_stored_rep()) {
      case MemoryRepresentation::Int8():
      case MemoryRepresentation::Uint8():
        opcode = kS390_StoreWord8;
        break;
      case MemoryRepresentation::Int16():
      case MemoryRepresentation::Uint16():
        opcode = kS390_StoreWord16;
        break;
      case MemoryRepresentation::Int32():
      case MemoryRepresentation::Uint32(): {
        opcode = kS390_StoreWord32;
        const Operation& reverse_op = selector->Get(value);
        if (reverse_op.Is<Opmask::kWord32ReverseBytes>()) {
          opcode = kS390_StoreReverse32;
          value = selector->input_at(value, 0);
        }
        break;
      }
      case MemoryRepresentation::Int64():
      case MemoryRepresentation::Uint64(): {
        opcode = kS390_StoreWord64;
        const Operation& reverse_op = selector->Get(value);
        if (reverse_op.Is<Opmask::kWord64ReverseBytes>()) {
          opcode = kS390_StoreReverse64;
          value = selector->input_at(value, 0);
        }
        break;
      }
      case MemoryRepresentation::Float16():
        UNIMPLEMENTED();
      case MemoryRepresentation::Float32():
        opcode = kS390_StoreFloat32;
        break;
      case MemoryRepresentation::Float64():
        opcode = kS390_StoreDouble;
        break;
      case MemoryRepresentation::AnyTagged():
      case MemoryRepresentation::TaggedPointer():
      case MemoryRepresentation::TaggedSigned():
        opcode = kS390_StoreCompressTagged;
        break;
      case MemoryRepresentation::AnyUncompressedTagged():
      case MemoryRepresentation::UncompressedTaggedPointer():
      case MemoryRepresentation::UncompressedTaggedSigned():
        opcode = kS390_StoreWord64;
        break;
      case MemoryRepresentation::Simd128(): {
        opcode = kS390_StoreSimd128;
        const Operation& reverse_op = selector->Get(value);
        // TODO(miladfarca): Rename this to `Opmask::kSimd128ReverseBytes` once
        // Turboshaft naming is decoupled from Turbofan naming.
        if (reverse_op.Is<Opmask::kSimd128Simd128ReverseBytes>()) {
          opcode = kS390_StoreReverseSimd128;
          value = selector->input_at(value, 0);
        }
        break;
      }
      case MemoryRepresentation::ProtectedPointer():
        // We never store directly to protected pointers from generated code.
        UNREACHABLE();
      case MemoryRepresentation::IndirectPointer():
      case MemoryRepresentation::SandboxedPointer():
      case MemoryRepresentation::Simd256():
        UNREACHABLE();
    }
 
    InstructionOperand inputs[4];
    size_t input_count = 0;
    AddressingMode addressing_mode =
        g.GetEffectiveAddressMemoryOperand(node, inputs, &input_count);
    InstructionCode code =
        opcode | AddressingModeField::encode(addressing_mode);
    InstructionOperand value_operand = g.UseRegister(value);
    inputs[input_count++] = value_operand;
    selector->Emit(code, 0, static_cast<InstructionOperand*>(nullptr),
                   input_count, inputs);
  }
}
 
void InstructionSelectorT::VisitStorePair(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitStore(OpIndex node) {
  StoreRepresentation store_rep = this->store_view(node).stored_rep();
  WriteBarrierKind write_barrier_kind = store_rep.write_barrier_kind();
  MachineRepresentation rep = store_rep.representation();
 
  if (v8_flags.enable_unconditional_write_barriers &&
      CanBeTaggedOrCompressedPointer(rep)) {
    write_barrier_kind = kFullWriteBarrier;
  }
 
    VisitGeneralStore(this, node, rep, write_barrier_kind);
}
 
void InstructionSelectorT::VisitProtectedStore(OpIndex node) {
  // TODO(eholk)
  UNIMPLEMENTED();
}
 
// Architecture supports unaligned access, therefore VisitLoad is used instead
void InstructionSelectorT::VisitUnalignedLoad(OpIndex node) { UNREACHABLE(); }
 
// Architecture supports unaligned access, therefore VisitStore is used instead
void InstructionSelectorT::VisitUnalignedStore(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitStackPointerGreaterThan(
    OpIndex node, FlagsContinuation* cont) {
  StackCheckKind kind;
  OpIndex value;
  const auto& op = this->turboshaft_graph()
                       ->Get(node)
                       .template Cast<StackPointerGreaterThanOp>();
  kind = op.kind;
  value = op.stack_limit();
  InstructionCode opcode =
      kArchStackPointerGreaterThan | MiscField::encode(static_cast<int>(kind));
 
  S390OperandGeneratorT g(this);
 
  // No outputs.
  InstructionOperand* const outputs = nullptr;
  const int output_count = 0;
 
  // Applying an offset to this stack check requires a temp register. Offsets
  // are only applied to the first stack check. If applying an offset, we must
  // ensure the input and temp registers do not alias, thus kUniqueRegister.
  InstructionOperand temps[] = {g.TempRegister()};
  const int temp_count = (kind == StackCheckKind::kJSFunctionEntry) ? 1 : 0;
  const auto register_mode = (kind == StackCheckKind::kJSFunctionEntry)
                                 ? OperandGenerator::kUniqueRegister
                                 : OperandGenerator::kRegister;
 
  InstructionOperand inputs[] = {g.UseRegisterWithMode(value, register_mode)};
  static constexpr int input_count = arraysize(inputs);
 
  EmitWithContinuation(opcode, output_count, outputs, input_count, inputs,
                       temp_count, temps, cont);
}
 
#if 0
static inline bool IsContiguousMask32(uint32_t value, int* mb, int* me) {
  int mask_width = base::bits::CountPopulation(value);
  int mask_msb = base::bits::CountLeadingZeros32(value);
  int mask_lsb = base::bits::CountTrailingZeros32(value);
  if ((mask_width == 0) || (mask_msb + mask_width + mask_lsb != 32))
    return false;
  *mb = mask_lsb + mask_width - 1;
  *me = mask_lsb;
  return true;
}
#endif
 
static inline bool IsContiguousMask64(uint64_t value, int* mb, int* me) {
  int mask_width = base::bits::CountPopulation(value);
  int mask_msb = base::bits::CountLeadingZeros64(value);
  int mask_lsb = base::bits::CountTrailingZeros64(value);
  if ((mask_width == 0) || (mask_msb + mask_width + mask_lsb != 64))
    return false;
  *mb = mask_lsb + mask_width - 1;
  *me = mask_lsb;
  return true;
}
 
void InstructionSelectorT::VisitWord64And(OpIndex node) {
  S390OperandGeneratorT g(this);
 
  const WordBinopOp& bitwise_and = Get(node).Cast<WordBinopOp>();
  int mb = 0;
  int me = 0;
  int64_t value;
  if (MatchSignedIntegralConstant(bitwise_and.right(), &value) &&
      IsContiguousMask64(value, &mb, &me)) {
    int sh = 0;
    OpIndex left = bitwise_and.left();
    const Operation& lhs = Get(left);
    if ((lhs.Is<Opmask::kWord64ShiftRightLogical>() ||
         lhs.Is<Opmask::kWord64ShiftLeft>()) &&
        CanCover(node, left)) {
      // Try to absorb left/right shift into rldic
      int64_t shift_by;
      const ShiftOp& shift_op = lhs.Cast<ShiftOp>();
      if (MatchIntegralWord64Constant(shift_op.right(), &shift_by) &&
          base::IsInRange(shift_by, 0, 63)) {
        left = shift_op.left();
        sh = shift_by;
        if (lhs.Is<Opmask::kWord64ShiftRightLogical>()) {
          // Adjust the mask such that it doesn't include any rotated bits.
          if (mb > 63 - sh) mb = 63 - sh;
          sh = (64 - sh) & 0x3F;
        } else {
          // Adjust the mask such that it doesn't include any rotated bits.
          if (me < sh) me = sh;
        }
      }
    }
    if (mb >= me) {
      bool match = false;
      ArchOpcode opcode;
      int mask;
      if (me == 0) {
        match = true;
        opcode = kS390_RotLeftAndClearLeft64;
        mask = mb;
      } else if (mb == 63) {
        match = true;
        opcode = kS390_RotLeftAndClearRight64;
        mask = me;
      } else if (sh && me <= sh && lhs.Is<Opmask::kWord64ShiftLeft>()) {
        match = true;
        opcode = kS390_RotLeftAndClear64;
        mask = mb;
      }
      if (match && CpuFeatures::IsSupported(GENERAL_INSTR_EXT)) {
        Emit(opcode, g.DefineAsRegister(node), g.UseRegister(left),
             g.TempImmediate(sh), g.TempImmediate(mask));
        return;
      }
    }
  }
  VisitWord64BinOp(this, node, kS390_And64, And64OperandMode);
}
 
void InstructionSelectorT::VisitWord64Shl(OpIndex node) {
  S390OperandGeneratorT g(this);
  const ShiftOp& shl = this->Get(node).template Cast<ShiftOp>();
  const Operation& lhs = this->Get(shl.left());
  int64_t value;
  if (lhs.Is<Opmask::kWord64BitwiseAnd>() &&
      MatchSignedIntegralConstant(shl.right(), &value) &&
      base::IsInRange(value, 0, 63)) {
    int sh = value;
    int mb;
    int me;
    const WordBinopOp& bitwise_and = lhs.Cast<WordBinopOp>();
    int64_t right_value;
    if (MatchSignedIntegralConstant(bitwise_and.right(), &right_value) &&
        IsContiguousMask64(right_value << sh, &mb, &me)) {
      // Adjust the mask such that it doesn't include any rotated bits.
      if (me < sh) me = sh;
      if (mb >= me) {
        bool match = false;
        ArchOpcode opcode;
        int mask;
        if (me == 0) {
          match = true;
          opcode = kS390_RotLeftAndClearLeft64;
          mask = mb;
        } else if (mb == 63) {
          match = true;
          opcode = kS390_RotLeftAndClearRight64;
          mask = me;
        } else if (sh && me <= sh) {
          match = true;
          opcode = kS390_RotLeftAndClear64;
          mask = mb;
        }
        if (match && CpuFeatures::IsSupported(GENERAL_INSTR_EXT)) {
          Emit(opcode, g.DefineAsRegister(node),
               g.UseRegister(bitwise_and.left()), g.TempImmediate(sh),
               g.TempImmediate(mask));
          return;
        }
      }
    }
  }
  VisitWord64BinOp(this, node, kS390_ShiftLeft64, Shift64OperandMode);
}
 
void InstructionSelectorT::VisitWord64Shr(OpIndex node) {
  S390OperandGeneratorT g(this);
  const ShiftOp& shr = this->Get(node).template Cast<ShiftOp>();
  const Operation& lhs = this->Get(shr.left());
  int64_t value;
  if (lhs.Is<Opmask::kWord64BitwiseAnd>() &&
      MatchSignedIntegralConstant(shr.right(), &value) &&
      base::IsInRange(value, 0, 63)) {
    int sh = value;
    int mb;
    int me;
    const WordBinopOp& bitwise_and = lhs.Cast<WordBinopOp>();
    uint64_t right_value;
    if (MatchUnsignedIntegralConstant(bitwise_and.right(), &right_value) &&
        IsContiguousMask64(static_cast<uint64_t>(right_value >> sh), &mb,
                           &me)) {
      // Adjust the mask such that it doesn't include any rotated bits.
      if (mb > 63 - sh) mb = 63 - sh;
      sh = (64 - sh) & 0x3F;
      if (mb >= me) {
        bool match = false;
        ArchOpcode opcode;
        int mask;
        if (me == 0) {
          match = true;
          opcode = kS390_RotLeftAndClearLeft64;
          mask = mb;
        } else if (mb == 63) {
          match = true;
          opcode = kS390_RotLeftAndClearRight64;
          mask = me;
        }
        if (match) {
          Emit(opcode, g.DefineAsRegister(node),
               g.UseRegister(bitwise_and.left()), g.TempImmediate(sh),
               g.TempImmediate(mask));
          return;
        }
      }
    }
  }
  VisitWord64BinOp(this, node, kS390_ShiftRight64, Shift64OperandMode);
}
 
static inline bool TryMatchSignExtInt16OrInt8FromWord32Sar(
    InstructionSelectorT* selector, OpIndex node) {
  S390OperandGeneratorT g(selector);
 
  const ShiftOp& sar = selector->Get(node).template Cast<ShiftOp>();
  const Operation& lhs = selector->Get(sar.left());
  if (selector->CanCover(node, sar.left()) &&
      lhs.Is<Opmask::kWord32ShiftLeft>()) {
    const ShiftOp& shl = lhs.Cast<ShiftOp>();
    uint64_t sar_value;
    uint64_t shl_value;
    if (selector->MatchUnsignedIntegralConstant(sar.right(), &sar_value) &&
        selector->MatchUnsignedIntegralConstant(shl.right(), &shl_value)) {
      uint32_t sar_by = sar_value;
      uint32_t shl_by = shl_value;
      if ((sar_by == shl_by) && (sar_by == 16)) {
        bool canEliminateZeroExt = ProduceWord32Result(selector, shl.left());
        selector->Emit(kS390_SignExtendWord16ToInt32,
                       canEliminateZeroExt ? g.DefineSameAsFirst(node)
                                           : g.DefineAsRegister(node),
                       g.UseRegister(shl.left()),
                       g.TempImmediate(!canEliminateZeroExt));
        return true;
      } else if ((sar_by == shl_by) && (sar_by == 24)) {
        bool canEliminateZeroExt = ProduceWord32Result(selector, shl.left());
        selector->Emit(kS390_SignExtendWord8ToInt32,
                       canEliminateZeroExt ? g.DefineSameAsFirst(node)
                                           : g.DefineAsRegister(node),
                       g.UseRegister(shl.left()),
                       g.TempImmediate(!canEliminateZeroExt));
        return true;
      }
    }
  }
  return false;
}
 
void InstructionSelectorT::VisitWord32Rol(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitWord64Rol(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitWord32Ctz(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitWord64Ctz(OpIndex node) { UNREACHABLE(); }
 
void InstructionSelectorT::VisitWord32ReverseBits(OpIndex node) {
  UNREACHABLE();
}
 
void InstructionSelectorT::VisitWord64ReverseBits(OpIndex node) {
  UNREACHABLE();
}
 
void InstructionSelectorT::VisitInt32AbsWithOverflow(OpIndex node) {
  VisitWord32UnaryOp(this, node, kS390_Abs32, OperandMode::kNone);
}
 
void InstructionSelectorT::VisitInt64AbsWithOverflow(OpIndex node) {
  VisitWord64UnaryOp(this, node, kS390_Abs64, OperandMode::kNone);
}
 
void InstructionSelectorT::VisitWord64ReverseBytes(OpIndex node) {
  S390OperandGeneratorT g(this);
  OpIndex input = this->Get(node).input(0);
  const Operation& input_op = this->Get(input);
  if (CanCover(node, input) && input_op.Is<LoadOp>()) {
    auto load = this->load_view(input);
    LoadRepresentation load_rep = load.loaded_rep();
    if (load_rep.representation() == MachineRepresentation::kWord64) {
      InstructionOperand outputs[] = {g.DefineAsRegister(node)};
      InstructionOperand inputs[3];
      size_t input_count = 0;
      AddressingMode mode =
          g.GetEffectiveAddressMemoryOperand(input, inputs, &input_count);
      Emit(kS390_LoadReverse64 | AddressingModeField::encode(mode), 1, outputs,
           input_count, inputs);
      return;
    }
  }
  Emit(kS390_LoadReverse64RR, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)));
}
 
void InstructionSelectorT::VisitWord32ReverseBytes(OpIndex node) {
  S390OperandGeneratorT g(this);
  OpIndex input = this->Get(node).input(0);
  const Operation& input_op = this->Get(input);
  if (CanCover(node, input) && input_op.Is<LoadOp>()) {
    auto load = this->load_view(input);
    LoadRepresentation load_rep = load.loaded_rep();
    if (load_rep.representation() == MachineRepresentation::kWord32) {
      InstructionOperand outputs[] = {g.DefineAsRegister(node)};
      InstructionOperand inputs[3];
      size_t input_count = 0;
      AddressingMode mode =
          g.GetEffectiveAddressMemoryOperand(input, inputs, &input_count);
      Emit(kS390_LoadReverse32 | AddressingModeField::encode(mode), 1, outputs,
           input_count, inputs);
      return;
    }
  }
  Emit(kS390_LoadReverse32RR, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)));
}
 
void InstructionSelectorT::VisitSimd128ReverseBytes(OpIndex node) {
  S390OperandGeneratorT g(this);
  OpIndex input = this->Get(node).input(0);
  const Operation& input_op = this->Get(input);
  if (CanCover(node, input) && input_op.Is<LoadOp>()) {
    auto load = this->load_view(input);
    LoadRepresentation load_rep = load.loaded_rep();
    if (load_rep.representation() == MachineRepresentation::kSimd128) {
      InstructionOperand outputs[] = {g.DefineAsRegister(node)};
      InstructionOperand inputs[3];
      size_t input_count = 0;
      AddressingMode mode =
          g.GetEffectiveAddressMemoryOperand(input, inputs, &input_count);
      Emit(kS390_LoadReverseSimd128 | AddressingModeField::encode(mode), 1,
           outputs, input_count, inputs);
      return;
    }
  }
  Emit(kS390_LoadReverseSimd128RR, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)));
}
 
template <class Matcher, ArchOpcode neg_opcode>
static inline bool TryMatchNegFromSub(InstructionSelectorT* selector,
                                      OpIndex node) {
  S390OperandGeneratorT g(selector);
  static_assert(neg_opcode == kS390_Neg32 || neg_opcode == kS390_Neg64,
                "Provided opcode is not a Neg opcode.");
  const WordBinopOp& sub_op = selector->Get(node).template Cast<WordBinopOp>();
  if (selector->MatchIntegralZero(sub_op.left())) {
    OpIndex value = sub_op.right();
    bool doZeroExt = DoZeroExtForResult(selector, node);
    bool canEliminateZeroExt = ProduceWord32Result(selector, value);
    if (doZeroExt) {
      selector->Emit(neg_opcode,
                     canEliminateZeroExt ? g.DefineSameAsFirst(node)
                                         : g.DefineAsRegister(node),
                     g.UseRegister(value),
                     g.TempImmediate(!canEliminateZeroExt));
    } else {
      selector->Emit(neg_opcode, g.DefineAsRegister(node),
                     g.UseRegister(value));
    }
    return true;
  }
  return false;
}
 
template <class Matcher, ArchOpcode shift_op>
bool TryMatchShiftFromMul(InstructionSelectorT* selector, OpIndex node) {
  S390OperandGeneratorT g(selector);
  const Operation& op = selector->Get(node);
  const WordBinopOp& mul_op = op.Cast<WordBinopOp>();
  OpIndex left = mul_op.left();
  OpIndex right = mul_op.right();
  if (g.CanBeImmediate(right, OperandMode::kInt32Imm) &&
      base::bits::IsPowerOfTwo(g.GetImmediate(right))) {
    int power = 63 - base::bits::CountLeadingZeros64(g.GetImmediate(right));
    bool doZeroExt = DoZeroExtForResult(selector, node);
    bool canEliminateZeroExt = ProduceWord32Result(selector, left);
    InstructionOperand dst = (doZeroExt && !canEliminateZeroExt &&
                              CpuFeatures::IsSupported(DISTINCT_OPS))
                                 ? g.DefineAsRegister(node)
                                 : g.DefineSameAsFirst(node);
 
    if (doZeroExt) {
      selector->Emit(shift_op, dst, g.UseRegister(left), g.UseImmediate(power),
                     g.TempImmediate(!canEliminateZeroExt));
    } else {
      selector->Emit(shift_op, dst, g.UseRegister(left), g.UseImmediate(power));
    }
    return true;
  }
  return false;
}
 
template <ArchOpcode opcode>
static inline bool TryMatchInt32OpWithOverflow(InstructionSelectorT* selector,
                                               OpIndex node,
                                               OperandModes mode) {
  OptionalOpIndex ovf = selector->FindProjection(node, 1);
  if (ovf.valid()) {
    FlagsContinuationT cont =
        FlagsContinuationT::ForSet(kOverflow, ovf.value());
    VisitWord32BinOp(selector, node, opcode, mode, &cont);
    return true;
  }
  return false;
}
 
static inline bool TryMatchInt32AddWithOverflow(InstructionSelectorT* selector,
                                                OpIndex node) {
  return TryMatchInt32OpWithOverflow<kS390_Add32>(selector, node,
                                                  AddOperandMode);
}
 
static inline bool TryMatchInt32SubWithOverflow(InstructionSelectorT* selector,
                                                OpIndex node) {
  return TryMatchInt32OpWithOverflow<kS390_Sub32>(selector, node,
                                                  SubOperandMode);
}
 
static inline bool TryMatchInt32MulWithOverflow(InstructionSelectorT* selector,
                                                OpIndex node) {
  OptionalOpIndex ovf = selector->FindProjection(node, 1);
  if (ovf.valid()) {
    if (CpuFeatures::IsSupported(MISC_INSTR_EXT2)) {
      TryMatchInt32OpWithOverflow<kS390_Mul32>(
          selector, node, OperandMode::kAllowRRR | OperandMode::kAllowRM);
    } else {
      FlagsContinuationT cont =
          FlagsContinuationT::ForSet(kNotEqual, ovf.value());
      VisitWord32BinOp(selector, node, kS390_Mul32WithOverflow,
                       OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps,
                       &cont);
    }
    return true;
  }
  return TryMatchShiftFromMul<Int32BinopMatcher, kS390_ShiftLeft32>(selector,
                                                                    node);
}
 
template <ArchOpcode opcode>
static inline bool TryMatchInt64OpWithOverflow(InstructionSelectorT* selector,
                                               OpIndex node,
                                               OperandModes mode) {
  OptionalOpIndex ovf = selector->FindProjection(node, 1);
  if (ovf.valid()) {
    FlagsContinuationT cont =
        FlagsContinuationT::ForSet(kOverflow, ovf.value());
    VisitWord64BinOp(selector, node, opcode, mode, &cont);
    return true;
  }
  return false;
}
 
static inline bool TryMatchInt64AddWithOverflow(InstructionSelectorT* selector,
                                                OpIndex node) {
  return TryMatchInt64OpWithOverflow<kS390_Add64>(selector, node,
                                                  AddOperandMode);
}
 
static inline bool TryMatchInt64SubWithOverflow(InstructionSelectorT* selector,
                                                OpIndex node) {
  return TryMatchInt64OpWithOverflow<kS390_Sub64>(selector, node,
                                                  SubOperandMode);
}
 
void EmitInt64MulWithOverflow(InstructionSelectorT* selector, OpIndex node,
                              FlagsContinuationT* cont) {
  S390OperandGeneratorT g(selector);
  OpIndex lhs = selector->input_at(node, 0);
  OpIndex rhs = selector->input_at(node, 1);
  InstructionOperand inputs[2];
  size_t input_count = 0;
  InstructionOperand outputs[1];
  size_t output_count = 0;
 
  inputs[input_count++] = g.UseUniqueRegister(lhs);
  inputs[input_count++] = g.UseUniqueRegister(rhs);
  outputs[output_count++] = g.DefineAsRegister(node);
  selector->EmitWithContinuation(kS390_Mul64WithOverflow, output_count, outputs,
                                 input_count, inputs, cont);
}
 
static inline bool TryMatchDoubleConstructFromInsert(
    InstructionSelectorT* selector, OpIndex node) {
  UNIMPLEMENTED();
}
 
#define null ([]() { return false; })
 
#define FLOAT_UNARY_OP_LIST(V)                                                 \
  V(Float64, TruncateFloat64ToUint32, kS390_DoubleToUint32,                    \
    OperandMode::kNone, null)                                                  \
  V(Float64, Float64SilenceNaN, kS390_Float64SilenceNaN, OperandMode::kNone,   \
    null)                                                                      \
  V(Float64, Float64Sqrt, kS390_SqrtDouble, OperandMode::kNone, null)          \
  V(Float64, Float64RoundUp, kS390_CeilDouble, OperandMode::kNone, null)       \
  V(Float64, Float64RoundTruncate, kS390_TruncateDouble, OperandMode::kNone,   \
    null)                                                                      \
  V(Float64, Float64RoundTiesEven, kS390_DoubleNearestInt, OperandMode::kNone, \
    null)                                                                      \
  V(Float64, Float64RoundTiesAway, kS390_RoundDouble, OperandMode::kNone,      \
    null)                                                                      \
  V(Float64, Float64RoundDown, kS390_FloorDouble, OperandMode::kNone, null)    \
  V(Float64, Float64Neg, kS390_NegDouble, OperandMode::kNone, null)            \
  V(Float64, Float64Abs, kS390_AbsDouble, OperandMode::kNone, null)            \
  V(Float32, Float32Sqrt, kS390_SqrtFloat, OperandMode::kNone, null)           \
  V(Float32, Float32RoundUp, kS390_CeilFloat, OperandMode::kNone, null)        \
  V(Float32, Float32RoundTruncate, kS390_TruncateFloat, OperandMode::kNone,    \
    null)                                                                      \
  V(Float32, Float32RoundTiesEven, kS390_FloatNearestInt, OperandMode::kNone,  \
    null)                                                                      \
  V(Float32, Float32RoundDown, kS390_FloorFloat, OperandMode::kNone, null)     \
  V(Float32, Float32Neg, kS390_NegFloat, OperandMode::kNone, null)             \
  V(Float32, Float32Abs, kS390_AbsFloat, OperandMode::kNone, null)             \
  V(Float64, BitcastFloat64ToInt64, kS390_BitcastDoubleToInt64,                \
    OperandMode::kNone, null)                                                  \
  V(Float32, BitcastFloat32ToInt32, kS390_BitcastFloat32ToInt32,               \
    OperandMode::kAllowRM, null)                                               \
  V(Word32, Float64ExtractHighWord32, kS390_DoubleExtractHighWord32,           \
    OperandMode::kNone, null)                                                  \
  /* TODO(john.yan): can use kAllowRM */                                       \
  V(Word32, Float64ExtractLowWord32, kS390_DoubleExtractLowWord32,             \
    OperandMode::kNone, null)                                                  \
  V(Float64, ChangeFloat64ToUint64, kS390_DoubleToUint64, OperandMode::kNone,  \
    null)                                                                      \
  V(Float64, ChangeFloat64ToInt64, kS390_DoubleToInt64, OperandMode::kNone,    \
    null)                                                                      \
  V(Float64, ChangeFloat64ToUint32, kS390_DoubleToUint32, OperandMode::kNone,  \
    null)                                                                      \
  V(Float64, ChangeFloat64ToInt32, kS390_DoubleToInt32, OperandMode::kNone,    \
    null)                                                                      \
  V(Float64, TruncateFloat64ToInt64, kS390_DoubleToInt64, OperandMode::kNone,  \
    null)                                                                      \
  V(Float64, TruncateFloat64ToFloat32, kS390_DoubleToFloat32,                  \
    OperandMode::kNone, null)                                                  \
  V(Float64, TruncateFloat64ToWord32, kArchTruncateDoubleToI,                  \
    OperandMode::kNone, null)                                                  \
  V(Float32, ChangeFloat32ToFloat64, kS390_Float32ToDouble,                    \
    OperandMode::kAllowRM, null)                                               \
  V(Float64, RoundFloat64ToInt32, kS390_DoubleToInt32, OperandMode::kNone, null)
 
#define FLOAT_BIN_OP_LIST(V)                                           \
  V(Float64, Float64Mul, kS390_MulDouble, OperandMode::kAllowRM, null) \
  V(Float64, Float64Add, kS390_AddDouble, OperandMode::kAllowRM, null) \
  V(Float64, Float64Min, kS390_MinDouble, OperandMode::kNone, null)    \
  V(Float64, Float64Max, kS390_MaxDouble, OperandMode::kNone, null)    \
  V(Float32, Float32Min, kS390_MinFloat, OperandMode::kNone, null)     \
  V(Float32, Float32Max, kS390_MaxFloat, OperandMode::kNone, null)     \
  V(Float32, Float32Div, kS390_DivFloat, OperandMode::kAllowRM, null)  \
  V(Float32, Float32Mul, kS390_MulFloat, OperandMode::kAllowRM, null)  \
  V(Float32, Float32Sub, kS390_SubFloat, OperandMode::kAllowRM, null)  \
  V(Float32, Float32Add, kS390_AddFloat, OperandMode::kAllowRM, null)  \
  V(Float64, Float64Sub, kS390_SubDouble, OperandMode::kAllowRM, null) \
  V(Float64, Float64Div, kS390_DivDouble, OperandMode::kAllowRM, null)
 
#define WORD32_UNARY_OP_LIST(V)                                              \
  V(Word32, SignExtendWord32ToInt64, kS390_SignExtendWord32ToInt64,          \
    OperandMode::kNone, null)                                                \
  V(Word32, SignExtendWord16ToInt64, kS390_SignExtendWord16ToInt64,          \
    OperandMode::kNone, null)                                                \
  V(Word32, SignExtendWord8ToInt64, kS390_SignExtendWord8ToInt64,            \
    OperandMode::kNone, null)                                                \
  V(Word32, SignExtendWord16ToInt32, kS390_SignExtendWord16ToInt32,          \
    OperandMode::kNone, null)                                                \
  V(Word32, SignExtendWord8ToInt32, kS390_SignExtendWord8ToInt32,            \
    OperandMode::kNone, null)                                                \
  V(Word32, Word32Popcnt, kS390_Popcnt32, OperandMode::kNone, null)          \
  V(Word32, Word32Clz, kS390_Cntlz32, OperandMode::kNone, null)              \
  V(Word32, BitcastInt32ToFloat32, kS390_BitcastInt32ToFloat32,              \
    OperandMode::kNone, null)                                                \
  V(Word32, ChangeUint32ToFloat64, kS390_Uint32ToDouble, OperandMode::kNone, \
    null)                                                                    \
  V(Word32, RoundUint32ToFloat32, kS390_Uint32ToFloat32, OperandMode::kNone, \
    null)                                                                    \
  V(Word32, RoundInt32ToFloat32, kS390_Int32ToFloat32, OperandMode::kNone,   \
    null)                                                                    \
  V(Word32, ChangeInt32ToFloat64, kS390_Int32ToDouble, OperandMode::kNone,   \
    null)                                                                    \
  V(Word32, ChangeInt32ToInt64, kS390_SignExtendWord32ToInt64,               \
    OperandMode::kNone, null)                                                \
  V(Word32, ChangeUint32ToUint64, kS390_Uint32ToUint64, OperandMode::kNone,  \
    [&]() -> bool {                                                          \
      if (ProduceWord32Result(this, this->input_at(node, 0))) {              \
        EmitIdentity(node);                                                  \
        return true;                                                         \
      }                                                                      \
      return false;                                                          \
    })
 
#define WORD32_BIN_OP_LIST(V)                                                  \
  V(Word32, Float64InsertHighWord32, kS390_DoubleInsertHighWord32,             \
    OperandMode::kAllowRRR,                                                    \
    [&]() -> bool { return TryMatchDoubleConstructFromInsert(this, node); })   \
  V(Word32, Float64InsertLowWord32, kS390_DoubleInsertLowWord32,               \
    OperandMode::kAllowRRR,                                                    \
    [&]() -> bool { return TryMatchDoubleConstructFromInsert(this, node); })   \
  V(Word32, Int32SubWithOverflow, kS390_Sub32, SubOperandMode,                 \
    ([&]() { return TryMatchInt32SubWithOverflow(this, node); }))              \
  V(Word32, Uint32MulHigh, kS390_MulHighU32,                                   \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word32, Uint32Mod, kS390_ModU32,                                           \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word32, Uint32Div, kS390_DivU32,                                           \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word32, Int32Mod, kS390_Mod32,                                             \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word32, Int32Div, kS390_Div32,                                             \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word32, Int32Mul, kS390_Mul32, MulOperandMode, ([&]() {                    \
      return TryMatchShiftFromMul<Int32BinopMatcher, kS390_ShiftLeft32>(this,  \
                                                                        node); \
    }))                                                                        \
  V(Word32, Int32MulHigh, kS390_MulHigh32,                                     \
    OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps, null)             \
  V(Word32, Int32Sub, kS390_Sub32, SubOperandMode, ([&]() {                    \
      return TryMatchNegFromSub<Int32BinopMatcher, kS390_Neg32>(this, node);   \
    }))                                                                        \
  V(Word32, Int32Add, kS390_Add32, AddOperandMode, null)                       \
  V(Word32, Word32Xor, kS390_Xor32, Xor32OperandMode, null)                    \
  V(Word32, Word32Ror, kS390_RotRight32,                                       \
    OperandMode::kAllowRI | OperandMode::kAllowRRR | OperandMode::kAllowRRI |  \
        OperandMode::kShift32Imm,                                              \
    null)                                                                      \
  V(Word32, Word32Shr, kS390_ShiftRight32, Shift32OperandMode, null)           \
  V(Word32, Word32Shl, kS390_ShiftLeft32, Shift32OperandMode, null)            \
  V(Word32, Int32AddWithOverflow, kS390_Add32, AddOperandMode,                 \
    ([&]() { return TryMatchInt32AddWithOverflow(this, node); }))              \
  V(Word32, Int32MulWithOverflow, kS390_Mul32, MulOperandMode,                 \
    ([&]() { return TryMatchInt32MulWithOverflow(this, node); }))              \
  V(Word32, Word32And, kS390_And32, And32OperandMode, null)                    \
  V(Word32, Word32Or, kS390_Or32, Or32OperandMode, null)                       \
  V(Word32, Word32Sar, kS390_ShiftRightArith32, Shift32OperandMode,            \
    [&]() { return TryMatchSignExtInt16OrInt8FromWord32Sar(this, node); })
 
#define WORD64_UNARY_OP_LIST(V)                                              \
  V(Word64, TruncateInt64ToInt32, kS390_Int64ToInt32, OperandMode::kNone,    \
    null)                                                                    \
  V(Word64, Word64Clz, kS390_Cntlz64, OperandMode::kNone, null)              \
  V(Word64, Word64Popcnt, kS390_Popcnt64, OperandMode::kNone, null)          \
  V(Word64, Int64SubWithOverflow, kS390_Sub64, SubOperandMode,               \
    ([&]() { return TryMatchInt64SubWithOverflow(this, node); }))            \
  V(Word64, BitcastInt64ToFloat64, kS390_BitcastInt64ToDouble,               \
    OperandMode::kNone, null)                                                \
  V(Word64, ChangeInt64ToFloat64, kS390_Int64ToDouble, OperandMode::kNone,   \
    null)                                                                    \
  V(Word64, RoundUint64ToFloat64, kS390_Uint64ToDouble, OperandMode::kNone,  \
    null)                                                                    \
  V(Word64, RoundUint64ToFloat32, kS390_Uint64ToFloat32, OperandMode::kNone, \
    null)                                                                    \
  V(Word64, RoundInt64ToFloat32, kS390_Int64ToFloat32, OperandMode::kNone,   \
    null)                                                                    \
  V(Word64, RoundInt64ToFloat64, kS390_Int64ToDouble, OperandMode::kNone, null)
 
#define WORD64_BIN_OP_LIST(V)                                                  \
  V(Word64, Int64AddWithOverflow, kS390_Add64, AddOperandMode,                 \
    ([&]() { return TryMatchInt64AddWithOverflow(this, node); }))              \
  V(Word64, Uint64MulHigh, kS390_MulHighU64, OperandMode::kAllowRRR, null)     \
  V(Word64, Uint64Mod, kS390_ModU64,                                           \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word64, Uint64Div, kS390_DivU64,                                           \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word64, Int64Mod, kS390_Mod64,                                             \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word64, Int64Div, kS390_Div64,                                             \
    OperandMode::kAllowRRM | OperandMode::kAllowRRR, null)                     \
  V(Word64, Int64MulHigh, kS390_MulHighS64, OperandMode::kAllowRRR, null)      \
  V(Word64, Int64Mul, kS390_Mul64, MulOperandMode, ([&]() {                    \
      return TryMatchShiftFromMul<Int64BinopMatcher, kS390_ShiftLeft64>(this,  \
                                                                        node); \
    }))                                                                        \
  V(Word64, Int64Sub, kS390_Sub64, SubOperandMode, ([&]() {                    \
      return TryMatchNegFromSub<Int64BinopMatcher, kS390_Neg64>(this, node);   \
    }))                                                                        \
  V(Word64, Word64Xor, kS390_Xor64, Xor64OperandMode, null)                    \
  V(Word64, Word64Or, kS390_Or64, Or64OperandMode, null)                       \
  V(Word64, Word64Ror, kS390_RotRight64, Shift64OperandMode, null)             \
  V(Word64, Int64Add, kS390_Add64, AddOperandMode, null)                       \
  V(Word64, Word64Sar, kS390_ShiftRightArith64, Shift64OperandMode, null)
 
#define DECLARE_UNARY_OP(type, name, op, mode, try_extra) \
  void InstructionSelectorT::Visit##name(OpIndex node) {  \
    if (std::function<bool()>(try_extra)()) return;       \
    Visit##type##UnaryOp(this, node, op, mode);           \
  }
 
#define DECLARE_BIN_OP(type, name, op, mode, try_extra)  \
  void InstructionSelectorT::Visit##name(OpIndex node) { \
    if (std::function<bool()>(try_extra)()) return;      \
    Visit##type##BinOp(this, node, op, mode);            \
  }
 
FLOAT_UNARY_OP_LIST(DECLARE_UNARY_OP)
FLOAT_BIN_OP_LIST(DECLARE_BIN_OP)
WORD32_UNARY_OP_LIST(DECLARE_UNARY_OP)
WORD32_BIN_OP_LIST(DECLARE_BIN_OP)
WORD64_UNARY_OP_LIST(DECLARE_UNARY_OP)
WORD64_BIN_OP_LIST(DECLARE_BIN_OP)
 
#undef FLOAT_UNARY_OP_LIST
#undef FLOAT_BIN_OP_LIST
#undef WORD32_UNARY_OP_LIST
#undef WORD32_BIN_OP_LIST
#undef WORD64_UNARY_OP_LIST
#undef WORD64_BIN_OP_LIST
#undef DECLARE_UNARY_OP
#undef DECLARE_BIN_OP
#undef null
 
void InstructionSelectorT::VisitTryTruncateFloat32ToInt64(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_Float32ToInt64, node);
}
 
void InstructionSelectorT::VisitTryTruncateFloat64ToInt64(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_DoubleToInt64, node);
}
 
void InstructionSelectorT::VisitTryTruncateFloat32ToUint64(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_Float32ToUint64, node);
}
 
void InstructionSelectorT::VisitTryTruncateFloat64ToUint64(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_DoubleToUint64, node);
}
 
void InstructionSelectorT::VisitTryTruncateFloat64ToInt32(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_DoubleToInt32, node);
}
 
void InstructionSelectorT::VisitTryTruncateFloat64ToUint32(OpIndex node) {
  VisitTryTruncateDouble(this, kS390_DoubleToUint32, node);
}
 
void InstructionSelectorT::VisitBitcastWord32ToWord64(OpIndex node) {
  DCHECK(SmiValuesAre31Bits());
  DCHECK(COMPRESS_POINTERS_BOOL);
  EmitIdentity(node);
}
 
void InstructionSelectorT::VisitFloat64Mod(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kS390_ModDouble, g.DefineAsFixed(node, d1),
       g.UseFixed(this->input_at(node, 0), d1),
       g.UseFixed(this->input_at(node, 1), d2))
      ->MarkAsCall();
}
 
void InstructionSelectorT::VisitFloat64Ieee754Unop(OpIndex node,
                                                   InstructionCode opcode) {
  S390OperandGeneratorT g(this);
  Emit(opcode, g.DefineAsFixed(node, d1),
       g.UseFixed(this->input_at(node, 0), d1))
      ->MarkAsCall();
}
 
void InstructionSelectorT::VisitFloat64Ieee754Binop(OpIndex node,
                                                    InstructionCode opcode) {
  S390OperandGeneratorT g(this);
  Emit(opcode, g.DefineAsFixed(node, d1),
       g.UseFixed(this->input_at(node, 0), d1),
       g.UseFixed(this->input_at(node, 1), d2))
      ->MarkAsCall();
}
 
void InstructionSelectorT::VisitInt64MulWithOverflow(OpIndex node) {
  OptionalOpIndex ovf = FindProjection(node, 1);
  if (ovf.valid()) {
    FlagsContinuation cont = FlagsContinuation::ForSet(
        CpuFeatures::IsSupported(MISC_INSTR_EXT2) ? kOverflow : kNotEqual,
        ovf.value());
    return EmitInt64MulWithOverflow(this, node, &cont);
  }
    FlagsContinuation cont;
    EmitInt64MulWithOverflow(this, node, &cont);
}
 
static bool CompareLogical(FlagsContinuationT* cont) {
  switch (cont->condition()) {
    case kUnsignedLessThan:
    case kUnsignedGreaterThanOrEqual:
    case kUnsignedLessThanOrEqual:
    case kUnsignedGreaterThan:
      return true;
    default:
      return false;
  }
  UNREACHABLE();
}
 
namespace {
 
// Shared routine for multiple compare operations.
void VisitCompare(InstructionSelectorT* selector, InstructionCode opcode,
                  InstructionOperand left, InstructionOperand right,
                  FlagsContinuationT* cont) {
  selector->EmitWithContinuation(opcode, left, right, cont);
}
 
void VisitLoadAndTest(InstructionSelectorT* selector, InstructionCode opcode,
                      OpIndex node, OpIndex value, FlagsContinuationT* cont,
                      bool discard_output = false);
 
// Shared routine for multiple word compare operations.
void VisitWordCompare(InstructionSelectorT* selector, OpIndex node,
                      InstructionCode opcode, FlagsContinuationT* cont,
                      OperandModes immediate_mode) {
  S390OperandGeneratorT g(selector);
  OpIndex lhs = selector->input_at(node, 0);
  OpIndex rhs = selector->input_at(node, 1);
 
  const Operation& op = selector->Get(node);
  DCHECK(op.Is<ComparisonOp>() || op.Is<Opmask::kWord32Sub>() ||
         op.Is<Opmask::kWord64Sub>());
  USE(op);
 
  InstructionOperand inputs[8];
  InstructionOperand outputs[1];
  size_t input_count = 0;
  size_t output_count = 0;
 
  // If one of the two inputs is an immediate, make sure it's on the right, or
  // if one of the two inputs is a memory operand, make sure it's on the left.
  int effect_level = selector->GetEffectLevel(node, cont);
 
  if ((!g.CanBeImmediate(rhs, immediate_mode) &&
       g.CanBeImmediate(lhs, immediate_mode)) ||
      (!g.CanBeMemoryOperand(opcode, node, rhs, effect_level) &&
       g.CanBeMemoryOperand(opcode, node, lhs, effect_level))) {
    if (!selector->IsCommutative(node)) cont->Commute();
    std::swap(lhs, rhs);
  }
 
  // check if compare with 0
  if (g.CanBeImmediate(rhs, immediate_mode) && g.GetImmediate(rhs) == 0) {
    DCHECK(opcode == kS390_Cmp32 || opcode == kS390_Cmp64);
    ArchOpcode load_and_test = (opcode == kS390_Cmp32)
                                   ? kS390_LoadAndTestWord32
                                   : kS390_LoadAndTestWord64;
    return VisitLoadAndTest(selector, load_and_test, node, lhs, cont, true);
  }
 
  inputs[input_count++] = g.UseRegister(lhs);
  if (g.CanBeMemoryOperand(opcode, node, rhs, effect_level)) {
    // generate memory operand
    AddressingMode addressing_mode = g.GetEffectiveAddressMemoryOperand(
        rhs, inputs, &input_count, OpcodeImmMode(opcode));
    opcode |= AddressingModeField::encode(addressing_mode);
  } else if (g.CanBeImmediate(rhs, immediate_mode)) {
    inputs[input_count++] = g.UseImmediate(rhs);
  } else {
    inputs[input_count++] = g.UseAnyExceptImmediate(rhs);
  }
 
  DCHECK(input_count <= 8 && output_count <= 1);
  selector->EmitWithContinuation(opcode, output_count, outputs, input_count,
                                 inputs, cont);
}
 
void VisitWord32Compare(InstructionSelectorT* selector, OpIndex node,
                        FlagsContinuationT* cont) {
  OperandModes mode =
      (CompareLogical(cont) ? OperandMode::kUint32Imm : OperandMode::kInt32Imm);
  VisitWordCompare(selector, node, kS390_Cmp32, cont, mode);
}
 
void VisitWord64Compare(InstructionSelectorT* selector, OpIndex node,
                        FlagsContinuationT* cont) {
  OperandModes mode =
      (CompareLogical(cont) ? OperandMode::kUint32Imm : OperandMode::kInt32Imm);
  VisitWordCompare(selector, node, kS390_Cmp64, cont, mode);
}
 
// Shared routine for multiple float32 compare operations.
void VisitFloat32Compare(InstructionSelectorT* selector, OpIndex node,
                         FlagsContinuationT* cont) {
  VisitWordCompare(selector, node, kS390_CmpFloat, cont, OperandMode::kNone);
}
 
// Shared routine for multiple float64 compare operations.
void VisitFloat64Compare(InstructionSelectorT* selector, OpIndex node,
                         FlagsContinuationT* cont) {
  VisitWordCompare(selector, node, kS390_CmpDouble, cont, OperandMode::kNone);
}
 
void VisitTestUnderMask(InstructionSelectorT* selector, OpIndex node,
                        FlagsContinuationT* cont) {
  const Operation& op = selector->Get(node);
  DCHECK(op.Is<Opmask::kWord32BitwiseAnd>() ||
         op.Is<Opmask::kWord64BitwiseAnd>());
  USE(op);
 
  ArchOpcode opcode;
  if (selector->Get(node).template TryCast<Opmask::kWord32BitwiseAnd>()) {
    opcode = kS390_Tst32;
  } else {
    opcode = kS390_Tst64;
  }
 
  S390OperandGeneratorT g(selector);
  OpIndex lhs = selector->input_at(node, 0);
  OpIndex rhs = selector->input_at(node, 1);
  if (!g.CanBeImmediate(rhs, OperandMode::kUint32Imm) &&
      g.CanBeImmediate(lhs, OperandMode::kUint32Imm)) {
    std::swap(lhs, rhs);
  }
  VisitCompare(selector, opcode, g.UseRegister(lhs),
               g.UseOperand(rhs, OperandMode::kUint32Imm), cont);
}
 
void VisitLoadAndTest(InstructionSelectorT* selector, InstructionCode opcode,
                      OpIndex node, OpIndex value, FlagsContinuationT* cont,
                      bool discard_output) {
  static_assert(kS390_LoadAndTestFloat64 - kS390_LoadAndTestWord32 == 3,
                "LoadAndTest Opcode shouldn't contain other opcodes.");
  // TODO(john.yan): Add support for Float32/Float64.
  DCHECK(opcode >= kS390_LoadAndTestWord32 ||
         opcode <= kS390_LoadAndTestWord64);
 
  S390OperandGeneratorT g(selector);
  InstructionOperand inputs[8];
  InstructionOperand outputs[2];
  size_t input_count = 0;
  size_t output_count = 0;
  bool use_value = false;
 
  int effect_level = selector->GetEffectLevel(node, cont);
 
  if (g.CanBeMemoryOperand(opcode, node, value, effect_level)) {
    // generate memory operand
    AddressingMode addressing_mode =
        g.GetEffectiveAddressMemoryOperand(value, inputs, &input_count);
    opcode |= AddressingModeField::encode(addressing_mode);
  } else {
    inputs[input_count++] = g.UseAnyExceptImmediate(value);
    use_value = true;
  }
 
  if (!discard_output && !use_value) {
    outputs[output_count++] = g.DefineAsRegister(value);
  }
 
  DCHECK(input_count <= 8 && output_count <= 2);
  selector->EmitWithContinuation(opcode, output_count, outputs, input_count,
                                 inputs, cont);
}
 
}  // namespace
 
void InstructionSelectorT::VisitWordCompareZero(OpIndex user, OpIndex value,
                                                FlagsContinuation* cont) {
  // Try to combine with comparisons against 0 by simply inverting the branch.
  ConsumeEqualZero(&user, &value, cont);
 
  FlagsCondition fc = cont->condition();
  if (CanCover(user, value)) {
    const Operation& value_op = this->Get(value);
    if (const ComparisonOp* comparison = value_op.TryCast<ComparisonOp>()) {
      if (comparison->kind == ComparisonOp::Kind::kEqual) {
        switch (comparison->rep.MapTaggedToWord().value()) {
          case RegisterRepresentation::Word32(): {
            cont->OverwriteAndNegateIfEqual(kEqual);
            if (this->MatchIntegralZero(comparison->right())) {
              // Try to combine the branch with a comparison.
              if (CanCover(value, comparison->left())) {
                const Operation& left_op = this->Get(comparison->left());
                if (left_op.Is<Opmask::kWord32Sub>()) {
                  return VisitWord32Compare(this, comparison->left(), cont);
                } else if (left_op.Is<Opmask::kWord32BitwiseAnd>()) {
                  return VisitTestUnderMask(this, comparison->left(), cont);
                }
              }
            }
            return VisitWord32Compare(this, value, cont);
          }
          case RegisterRepresentation::Word64(): {
            cont->OverwriteAndNegateIfEqual(kEqual);
            if (this->MatchIntegralZero(comparison->right())) {
              // Try to combine the branch with a comparison.
              if (CanCover(value, comparison->left())) {
                const Operation& left_op = this->Get(comparison->left());
                if (left_op.Is<Opmask::kWord64Sub>()) {
                  return VisitWord64Compare(this, comparison->left(), cont);
                } else if (left_op.Is<Opmask::kWord64BitwiseAnd>()) {
                  return VisitTestUnderMask(this, comparison->left(), cont);
                }
              }
            }
            return VisitWord64Compare(this, value, cont);
          }
          case RegisterRepresentation::Float32():
            cont->OverwriteAndNegateIfEqual(kEqual);
            return VisitFloat32Compare(this, value, cont);
          case RegisterRepresentation::Float64():
            cont->OverwriteAndNegateIfEqual(kEqual);
            return VisitFloat64Compare(this, value, cont);
          default:
            break;
        }
      } else {
        switch (comparison->rep.MapTaggedToWord().value()) {
          case RegisterRepresentation::Word32():
            cont->OverwriteAndNegateIfEqual(
                GetComparisonFlagCondition(*comparison));
            return VisitWord32Compare(this, value, cont);
          case RegisterRepresentation::Word64():
            cont->OverwriteAndNegateIfEqual(
                GetComparisonFlagCondition(*comparison));
            return VisitWord64Compare(this, value, cont);
          case RegisterRepresentation::Float32():
            switch (comparison->kind) {
              case ComparisonOp::Kind::kSignedLessThan:
                cont->OverwriteAndNegateIfEqual(kUnsignedLessThan);
                return VisitFloat32Compare(this, value, cont);
              case ComparisonOp::Kind::kSignedLessThanOrEqual:
                cont->OverwriteAndNegateIfEqual(kUnsignedLessThanOrEqual);
                return VisitFloat32Compare(this, value, cont);
              default:
                UNREACHABLE();
            }
          case RegisterRepresentation::Float64():
            switch (comparison->kind) {
              case ComparisonOp::Kind::kSignedLessThan:
                cont->OverwriteAndNegateIfEqual(kUnsignedLessThan);
                return VisitFloat64Compare(this, value, cont);
              case ComparisonOp::Kind::kSignedLessThanOrEqual:
                cont->OverwriteAndNegateIfEqual(kUnsignedLessThanOrEqual);
                return VisitFloat64Compare(this, value, cont);
              default:
                UNREACHABLE();
            }
          default:
            break;
        }
      }
    } else if (const ProjectionOp* projection =
                   value_op.TryCast<ProjectionOp>()) {
      // Check if this is the overflow output projection of an
      // <Operation>WithOverflow node.
      if (projection->index == 1u) {
        // We cannot combine the <Operation>WithOverflow with this branch
        // unless the 0th projection (the use of the actual value of the
        // <Operation> is either nullptr, which means there's no use of the
        // actual value, or was already defined, which means it is scheduled
        // *AFTER* this branch).
        OpIndex node = projection->input();
        if (const OverflowCheckedBinopOp* binop =
                TryCast<OverflowCheckedBinopOp>(node);
            binop && CanDoBranchIfOverflowFusion(node)) {
          const bool is64 = binop->rep == WordRepresentation::Word64();
          switch (binop->kind) {
            case OverflowCheckedBinopOp::Kind::kSignedAdd:
              cont->OverwriteAndNegateIfEqual(kOverflow);
              if (is64) {
                return VisitWord64BinOp(this, node, kS390_Add64, AddOperandMode,
                                        cont);
              } else {
                return VisitWord32BinOp(this, node, kS390_Add32, AddOperandMode,
                                        cont);
              }
            case OverflowCheckedBinopOp::Kind::kSignedSub:
              cont->OverwriteAndNegateIfEqual(kOverflow);
              if (is64) {
                return VisitWord64BinOp(this, node, kS390_Sub64, AddOperandMode,
                                        cont);
              } else {
                return VisitWord32BinOp(this, node, kS390_Sub32, AddOperandMode,
                                        cont);
              }
            case OverflowCheckedBinopOp::Kind::kSignedMul:
              if (is64) {
                cont->OverwriteAndNegateIfEqual(
                    CpuFeatures::IsSupported(MISC_INSTR_EXT2) ? kOverflow
                                                              : kNotEqual);
                return EmitInt64MulWithOverflow(this, node, cont);
 
              } else {
                if (CpuFeatures::IsSupported(MISC_INSTR_EXT2)) {
                  cont->OverwriteAndNegateIfEqual(kOverflow);
                  return VisitWord32BinOp(
                      this, node, kS390_Mul32,
                      OperandMode::kAllowRRR | OperandMode::kAllowRM, cont);
                } else {
                  cont->OverwriteAndNegateIfEqual(kNotEqual);
                  return VisitWord32BinOp(
                      this, node, kS390_Mul32WithOverflow,
                      OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps,
                      cont);
                }
              }
            default:
              break;
          }
        } else if (const OverflowCheckedUnaryOp* unop =
                       TryCast<OverflowCheckedUnaryOp>(node);
                   unop && CanDoBranchIfOverflowFusion(node)) {
          const bool is64 = unop->rep == WordRepresentation::Word64();
          switch (unop->kind) {
            case OverflowCheckedUnaryOp::Kind::kAbs:
              if (is64) {
                cont->OverwriteAndNegateIfEqual(kOverflow);
                return VisitWord64UnaryOp(this, node, kS390_Abs64,
                                          OperandMode::kNone, cont);
              } else {
                cont->OverwriteAndNegateIfEqual(kOverflow);
                return VisitWord32UnaryOp(this, node, kS390_Abs32,
                                          OperandMode::kNone, cont);
              }
            default:
              break;
          }
        }
      }
    } else if (value_op.Is<Opmask::kWord32Sub>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord32Compare(this, value, cont);
    } else if (value_op.Is<Opmask::kWord32BitwiseAnd>()) {
      return VisitTestUnderMask(this, value, cont);
    } else if (value_op.Is<LoadOp>()) {
      auto load = this->load_view(value);
      LoadRepresentation load_rep = load.loaded_rep();
      switch (load_rep.representation()) {
        case MachineRepresentation::kWord32:
          return VisitLoadAndTest(this, kS390_LoadAndTestWord32, user, value,
                                  cont);
        default:
          break;
      }
    } else if (value_op.Is<Opmask::kWord32BitwiseOr>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord32BinOp(this, value, kS390_Or32, Or32OperandMode, cont);
    } else if (value_op.Is<Opmask::kWord32BitwiseXor>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord32BinOp(this, value, kS390_Xor32, Xor32OperandMode,
                                cont);
    } else if (value_op.Is<Opmask::kWord64Sub>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord64Compare(this, value, cont);
    } else if (value_op.Is<Opmask::kWord64BitwiseAnd>()) {
      return VisitTestUnderMask(this, value, cont);
    } else if (value_op.Is<Opmask::kWord64BitwiseOr>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord64BinOp(this, value, kS390_Or64, Or64OperandMode, cont);
    } else if (value_op.Is<Opmask::kWord64BitwiseXor>()) {
      if (fc == kNotEqual || fc == kEqual)
        return VisitWord64BinOp(this, value, kS390_Xor64, Xor64OperandMode,
                                cont);
    } else if (value_op.Is<StackPointerGreaterThanOp>()) {
      cont->OverwriteAndNegateIfEqual(kStackPointerGreaterThanCondition);
      return VisitStackPointerGreaterThan(value, cont);
    }
  }
  // Branch could not be combined with a compare, emit LoadAndTest
  VisitLoadAndTest(this, kS390_LoadAndTestWord32, user, value, cont, true);
}
 
void InstructionSelectorT::VisitSwitch(OpIndex node, const SwitchInfo& sw) {
  S390OperandGeneratorT g(this);
  InstructionOperand value_operand = g.UseRegister(this->input_at(node, 0));
 
  // Emit either ArchTableSwitch or ArchBinarySearchSwitch.
  if (enable_switch_jump_table_ ==
      InstructionSelector::kEnableSwitchJumpTable) {
  static const size_t kMaxTableSwitchValueRange = 2 << 16;
  size_t table_space_cost = 4 + sw.value_range();
  size_t table_time_cost = 3;
  size_t lookup_space_cost = 3 + 2 * sw.case_count();
  size_t lookup_time_cost = sw.case_count();
  if (sw.case_count() > 0 &&
      table_space_cost + 3 * table_time_cost <=
          lookup_space_cost + 3 * lookup_time_cost &&
      sw.min_value() > std::numeric_limits<int32_t>::min() &&
      sw.value_range() <= kMaxTableSwitchValueRange) {
      InstructionOperand index_operand = value_operand;
      if (sw.min_value()) {
      index_operand = g.TempRegister();
      Emit(kS390_Lay | AddressingModeField::encode(kMode_MRI), index_operand,
           value_operand, g.TempImmediate(-sw.min_value()));
      }
      InstructionOperand index_operand_zero_ext = g.TempRegister();
      Emit(kS390_Uint32ToUint64, index_operand_zero_ext, index_operand);
      index_operand = index_operand_zero_ext;
      // Generate a table lookup.
      return EmitTableSwitch(sw, index_operand);
  }
  }
 
  // Generate a tree of conditional jumps.
  return EmitBinarySearchSwitch(sw, value_operand);
}
 
void InstructionSelectorT::VisitWord32Equal(OpIndex const node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kEqual, node);
    const ComparisonOp& op = this->Get(node).template Cast<ComparisonOp>();
    if (this->MatchIntegralZero(op.right())) {
      return VisitLoadAndTest(this, kS390_LoadAndTestWord32, node, op.left(),
                              &cont, true);
    }
  VisitWord32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitInt32LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kSignedLessThan, node);
  VisitWord32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitInt32LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kSignedLessThanOrEqual, node);
  VisitWord32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitUint32LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kUnsignedLessThan, node);
  VisitWord32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitUint32LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kUnsignedLessThanOrEqual, node);
  VisitWord32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitWord64Equal(OpIndex const node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kEqual, node);
    const ComparisonOp& op = this->Get(node).template Cast<ComparisonOp>();
    if (this->MatchIntegralZero(op.right())) {
      return VisitLoadAndTest(this, kS390_LoadAndTestWord64, node, op.left(),
                              &cont, true);
    }
  VisitWord64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitInt64LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kSignedLessThan, node);
  VisitWord64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitInt64LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kSignedLessThanOrEqual, node);
  VisitWord64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitUint64LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kUnsignedLessThan, node);
  VisitWord64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitUint64LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kUnsignedLessThanOrEqual, node);
  VisitWord64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitTruncateFloat64ToFloat16RawBits(OpIndex node) {
  UNIMPLEMENTED();
}
 
void InstructionSelectorT::VisitChangeFloat16RawBitsToFloat64(OpIndex node) {
  UNIMPLEMENTED();
}
 
void InstructionSelectorT::VisitFloat32Equal(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kEqual, node);
  VisitFloat32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitFloat32LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kUnsignedLessThan, node);
  VisitFloat32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitFloat32LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kUnsignedLessThanOrEqual, node);
  VisitFloat32Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitFloat64Equal(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kEqual, node);
  VisitFloat64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitFloat64LessThan(OpIndex node) {
  FlagsContinuation cont = FlagsContinuation::ForSet(kUnsignedLessThan, node);
  VisitFloat64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitFloat64LessThanOrEqual(OpIndex node) {
  FlagsContinuation cont =
      FlagsContinuation::ForSet(kUnsignedLessThanOrEqual, node);
  VisitFloat64Compare(this, node, &cont);
}
 
void InstructionSelectorT::VisitBitcastWord32PairToFloat64(OpIndex node) {
  S390OperandGeneratorT g(this);
  const auto& bitcast = this->Cast<BitcastWord32PairToFloat64Op>(node);
  OpIndex hi = bitcast.high_word32();
  OpIndex lo = bitcast.low_word32();
 
  InstructionOperand temps[] = {g.TempRegister()};
  Emit(kS390_DoubleFromWord32Pair, g.DefineAsRegister(node), g.UseRegister(hi),
       g.UseRegister(lo), arraysize(temps), temps);
}
 
bool InstructionSelectorT::ZeroExtendsWord32ToWord64NoPhis(OpIndex node) {
  UNIMPLEMENTED();
}
 
void InstructionSelectorT::EmitMoveParamToFPR(OpIndex node, int index) {}
 
void InstructionSelectorT::EmitMoveFPRToParam(InstructionOperand* op,
                                              LinkageLocation location) {}
 
void InstructionSelectorT::EmitPrepareArguments(
    ZoneVector<PushParameter>* arguments, const CallDescriptor* call_descriptor,
    OpIndex node) {
  S390OperandGeneratorT g(this);
 
  // Prepare for C function call.
  if (call_descriptor->IsCFunctionCall()) {
      Emit(kArchPrepareCallCFunction | MiscField::encode(static_cast<int>(
                                           call_descriptor->ParameterCount())),
           0, nullptr, 0, nullptr);
 
      // Poke any stack arguments.
      int slot = kStackFrameExtraParamSlot;
      for (PushParameter input : (*arguments)) {
        if (!input.node.valid()) continue;
        Emit(kS390_StoreToStackSlot, g.NoOutput(), g.UseRegister(input.node),
             g.TempImmediate(slot));
        ++slot;
      }
  } else {
      // Push any stack arguments.
      int stack_decrement = 0;
      for (PushParameter input : base::Reversed(*arguments)) {
      stack_decrement += kSystemPointerSize;
      // Skip any alignment holes in pushed nodes.
      if (!input.node.valid()) continue;
      InstructionOperand decrement = g.UseImmediate(stack_decrement);
      stack_decrement = 0;
      Emit(kS390_Push, g.NoOutput(), decrement, g.UseRegister(input.node));
      }
  }
}
 
void InstructionSelectorT::VisitMemoryBarrier(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kArchNop, g.NoOutput());
}
 
bool InstructionSelectorT::IsTailCallAddressImmediate() { return false; }
 
void InstructionSelectorT::VisitWord32AtomicLoad(OpIndex node) {
  auto load = this->load_view(node);
  LoadRepresentation load_rep = load.loaded_rep();
  VisitLoad(node, node, SelectLoadOpcode(load_rep));
}
 
void InstructionSelectorT::VisitWord32AtomicStore(OpIndex node) {
  auto store = this->store_view(node);
  AtomicStoreParameters store_params(store.stored_rep().representation(),
                                     store.stored_rep().write_barrier_kind(),
                                     store.memory_order().value(),
                                     store.access_kind());
  VisitGeneralStore(this, node, store_params.representation());
}
 
void VisitAtomicExchange(InstructionSelectorT* selector, OpIndex node,
                         ArchOpcode opcode, AtomicWidth width) {
  S390OperandGeneratorT g(selector);
  const AtomicRMWOp& atomic_op = selector->Cast<AtomicRMWOp>(node);
  OpIndex base = atomic_op.base();
  OpIndex index = atomic_op.index();
  OpIndex value = atomic_op.value();
 
  AddressingMode addressing_mode = kMode_MRR;
  InstructionOperand inputs[3];
  size_t input_count = 0;
  inputs[input_count++] = g.UseUniqueRegister(base);
  inputs[input_count++] = g.UseUniqueRegister(index);
  inputs[input_count++] = g.UseUniqueRegister(value);
  InstructionOperand outputs[1];
  outputs[0] = g.DefineAsRegister(node);
  InstructionCode code = opcode | AddressingModeField::encode(addressing_mode) |
                         AtomicWidthField::encode(width);
  selector->Emit(code, 1, outputs, input_count, inputs);
}
 
void InstructionSelectorT::VisitWord32AtomicExchange(OpIndex node) {
  ArchOpcode opcode;
  const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
  if (atomic_op.memory_rep == MemoryRepresentation::Int8()) {
    opcode = kAtomicExchangeInt8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
    opcode = kAtomicExchangeUint8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Int16()) {
    opcode = kAtomicExchangeInt16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
    opcode = kAtomicExchangeUint16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Int32() ||
             atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
    opcode = kAtomicExchangeWord32;
  } else {
    UNREACHABLE();
  }
  VisitAtomicExchange(this, node, opcode, AtomicWidth::kWord32);
}
 
void InstructionSelectorT::VisitWord64AtomicExchange(OpIndex node) {
  ArchOpcode opcode;
  const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
  if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
    opcode = kAtomicExchangeUint8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
    opcode = kAtomicExchangeUint16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
    opcode = kAtomicExchangeWord32;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint64()) {
    opcode = kS390_Word64AtomicExchangeUint64;
  } else {
    UNREACHABLE();
  }
  VisitAtomicExchange(this, node, opcode, AtomicWidth::kWord64);
}
 
void VisitAtomicCompareExchange(InstructionSelectorT* selector, OpIndex node,
                                ArchOpcode opcode, AtomicWidth width) {
  S390OperandGeneratorT g(selector);
  const AtomicRMWOp& atomic_op = selector->Cast<AtomicRMWOp>(node);
  OpIndex base = atomic_op.base();
  OpIndex index = atomic_op.index();
  OpIndex old_value = atomic_op.expected().value();
  OpIndex new_value = atomic_op.value();
 
  InstructionOperand inputs[4];
  size_t input_count = 0;
  inputs[input_count++] = g.UseUniqueRegister(old_value);
  inputs[input_count++] = g.UseUniqueRegister(new_value);
  inputs[input_count++] = g.UseUniqueRegister(base);
 
  AddressingMode addressing_mode;
  if (g.CanBeImmediate(index, OperandMode::kInt20Imm)) {
    inputs[input_count++] = g.UseImmediate(index);
    addressing_mode = kMode_MRI;
  } else {
    inputs[input_count++] = g.UseUniqueRegister(index);
    addressing_mode = kMode_MRR;
  }
 
  InstructionOperand outputs[1];
  size_t output_count = 0;
  outputs[output_count++] = g.DefineSameAsFirst(node);
 
  InstructionCode code = opcode | AddressingModeField::encode(addressing_mode) |
                         AtomicWidthField::encode(width);
  selector->Emit(code, output_count, outputs, input_count, inputs);
}
 
void InstructionSelectorT::VisitWord32AtomicCompareExchange(OpIndex node) {
  const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
  ArchOpcode opcode;
  if (atomic_op.memory_rep == MemoryRepresentation::Int8()) {
    opcode = kAtomicCompareExchangeInt8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
    opcode = kAtomicCompareExchangeUint8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Int16()) {
    opcode = kAtomicCompareExchangeInt16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
    opcode = kAtomicCompareExchangeUint16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Int32() ||
             atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
    opcode = kAtomicCompareExchangeWord32;
  } else {
    UNREACHABLE();
  }
  VisitAtomicCompareExchange(this, node, opcode, AtomicWidth::kWord32);
}
 
void InstructionSelectorT::VisitWord64AtomicCompareExchange(OpIndex node) {
  const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
  ArchOpcode opcode;
  if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
    opcode = kAtomicCompareExchangeUint8;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
    opcode = kAtomicCompareExchangeUint16;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
    opcode = kAtomicCompareExchangeWord32;
  } else if (atomic_op.memory_rep == MemoryRepresentation::Uint64()) {
    opcode = kS390_Word64AtomicCompareExchangeUint64;
  } else {
    UNREACHABLE();
  }
  VisitAtomicCompareExchange(this, node, opcode, AtomicWidth::kWord64);
}
 
void VisitAtomicBinop(InstructionSelectorT* selector, OpIndex node,
                      ArchOpcode opcode, AtomicWidth width) {
  S390OperandGeneratorT g(selector);
  const AtomicRMWOp& atomic_op = selector->Cast<AtomicRMWOp>(node);
  OpIndex base = atomic_op.base();
  OpIndex index = atomic_op.index();
  OpIndex value = atomic_op.value();
 
  InstructionOperand inputs[3];
  size_t input_count = 0;
  inputs[input_count++] = g.UseUniqueRegister(base);
 
  AddressingMode addressing_mode;
  if (g.CanBeImmediate(index, OperandMode::kInt20Imm)) {
    inputs[input_count++] = g.UseImmediate(index);
    addressing_mode = kMode_MRI;
  } else {
    inputs[input_count++] = g.UseUniqueRegister(index);
    addressing_mode = kMode_MRR;
  }
 
  inputs[input_count++] = g.UseUniqueRegister(value);
 
  InstructionOperand outputs[1];
  size_t output_count = 0;
  outputs[output_count++] = g.DefineAsRegister(node);
 
  InstructionOperand temps[1];
  size_t temp_count = 0;
  temps[temp_count++] = g.TempRegister();
 
  InstructionCode code = opcode | AddressingModeField::encode(addressing_mode) |
                         AtomicWidthField::encode(width);
  selector->Emit(code, output_count, outputs, input_count, inputs, temp_count,
                 temps);
}
 
void InstructionSelectorT::VisitWord32AtomicBinaryOperation(
    OpIndex node, ArchOpcode int8_op, ArchOpcode uint8_op, ArchOpcode int16_op,
    ArchOpcode uint16_op, ArchOpcode word32_op) {
  ArchOpcode opcode;
    const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
    if (atomic_op.memory_rep == MemoryRepresentation::Int8()) {
      opcode = int8_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
      opcode = uint8_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Int16()) {
      opcode = int16_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
      opcode = uint16_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Int32() ||
               atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
      opcode = word32_op;
    } else {
      UNREACHABLE();
    }
  VisitAtomicBinop(this, node, opcode, AtomicWidth::kWord32);
}
 
#define VISIT_ATOMIC_BINOP(op)                                           \
  void InstructionSelectorT::VisitWord32Atomic##op(OpIndex node) {       \
    VisitWord32AtomicBinaryOperation(                                    \
        node, kAtomic##op##Int8, kAtomic##op##Uint8, kAtomic##op##Int16, \
        kAtomic##op##Uint16, kAtomic##op##Word32);                       \
  }
VISIT_ATOMIC_BINOP(Add)
VISIT_ATOMIC_BINOP(Sub)
VISIT_ATOMIC_BINOP(And)
VISIT_ATOMIC_BINOP(Or)
VISIT_ATOMIC_BINOP(Xor)
#undef VISIT_ATOMIC_BINOP
 
void InstructionSelectorT::VisitWord64AtomicBinaryOperation(
    OpIndex node, ArchOpcode uint8_op, ArchOpcode uint16_op,
    ArchOpcode word32_op, ArchOpcode word64_op) {
  ArchOpcode opcode;
    const AtomicRMWOp& atomic_op = this->Get(node).template Cast<AtomicRMWOp>();
    if (atomic_op.memory_rep == MemoryRepresentation::Uint8()) {
      opcode = uint8_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Uint16()) {
      opcode = uint16_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Uint32()) {
      opcode = word32_op;
    } else if (atomic_op.memory_rep == MemoryRepresentation::Uint64()) {
      opcode = word64_op;
    } else {
      UNREACHABLE();
    }
  VisitAtomicBinop(this, node, opcode, AtomicWidth::kWord64);
}
 
#define VISIT_ATOMIC64_BINOP(op)                                               \
  void InstructionSelectorT::VisitWord64Atomic##op(OpIndex node) {             \
    VisitWord64AtomicBinaryOperation(node, kAtomic##op##Uint8,                 \
                                     kAtomic##op##Uint16, kAtomic##op##Word32, \
                                     kS390_Word64Atomic##op##Uint64);          \
  }
VISIT_ATOMIC64_BINOP(Add)
VISIT_ATOMIC64_BINOP(Sub)
VISIT_ATOMIC64_BINOP(And)
VISIT_ATOMIC64_BINOP(Or)
VISIT_ATOMIC64_BINOP(Xor)
#undef VISIT_ATOMIC64_BINOP
 
void InstructionSelectorT::VisitWord64AtomicLoad(OpIndex node) {
  auto load = this->load_view(node);
  LoadRepresentation load_rep = load.loaded_rep();
  VisitLoad(node, node, SelectLoadOpcode(load_rep));
}
 
void InstructionSelectorT::VisitWord64AtomicStore(OpIndex node) {
  auto store = this->store_view(node);
  AtomicStoreParameters store_params(store.stored_rep().representation(),
                                     store.stored_rep().write_barrier_kind(),
                                     store.memory_order().value(),
                                     store.access_kind());
  VisitGeneralStore(this, node, store_params.representation());
}
 
#define SIMD_TYPES(V) \
  V(F64x2)            \
  V(F32x4)            \
  V(I64x2)            \
  V(I32x4)            \
  V(I16x8)            \
  V(I8x16)
 
#define SIMD_BINOP_LIST(V) \
  V(F64x2Add)              \
  V(F64x2Sub)              \
  V(F64x2Mul)              \
  V(F64x2Div)              \
  V(F64x2Eq)               \
  V(F64x2Ne)               \
  V(F64x2Lt)               \
  V(F64x2Le)               \
  V(F64x2Min)              \
  V(F64x2Max)              \
  V(F64x2Pmin)             \
  V(F64x2Pmax)             \
  V(F32x4Add)              \
  V(F32x4Sub)              \
  V(F32x4Mul)              \
  V(F32x4Eq)               \
  V(F32x4Ne)               \
  V(F32x4Lt)               \
  V(F32x4Le)               \
  V(F32x4Div)              \
  V(F32x4Min)              \
  V(F32x4Max)              \
  V(F32x4Pmin)             \
  V(F32x4Pmax)             \
  V(I64x2Add)              \
  V(I64x2Sub)              \
  V(I64x2Mul)              \
  V(I64x2Eq)               \
  V(I64x2ExtMulLowI32x4S)  \
  V(I64x2ExtMulHighI32x4S) \
  V(I64x2ExtMulLowI32x4U)  \
  V(I64x2ExtMulHighI32x4U) \
  V(I64x2Ne)               \
  V(I64x2GtS)              \
  V(I64x2GeS)              \
  V(I64x2Shl)              \
  V(I64x2ShrS)             \
  V(I64x2ShrU)             \
  V(I32x4Add)              \
  V(I32x4Sub)              \
  V(I32x4Mul)              \
  V(I32x4MinS)             \
  V(I32x4MinU)             \
  V(I32x4MaxS)             \
  V(I32x4MaxU)             \
  V(I32x4Eq)               \
  V(I32x4Ne)               \
  V(I32x4GtS)              \
  V(I32x4GeS)              \
  V(I32x4GtU)              \
  V(I32x4GeU)              \
  V(I32x4ExtMulLowI16x8S)  \
  V(I32x4ExtMulHighI16x8S) \
  V(I32x4ExtMulLowI16x8U)  \
  V(I32x4ExtMulHighI16x8U) \
  V(I32x4Shl)              \
  V(I32x4ShrS)             \
  V(I32x4ShrU)             \
  V(I32x4DotI16x8S)        \
  V(I16x8Add)              \
  V(I16x8Sub)              \
  V(I16x8Mul)              \
  V(I16x8MinS)             \
  V(I16x8MinU)             \
  V(I16x8MaxS)             \
  V(I16x8MaxU)             \
  V(I16x8Eq)               \
  V(I16x8Ne)               \
  V(I16x8GtS)              \
  V(I16x8GeS)              \
  V(I16x8GtU)              \
  V(I16x8GeU)              \
  V(I16x8SConvertI32x4)    \
  V(I16x8UConvertI32x4)    \
  V(I16x8RoundingAverageU) \
  V(I16x8ExtMulLowI8x16S)  \
  V(I16x8ExtMulHighI8x16S) \
  V(I16x8ExtMulLowI8x16U)  \
  V(I16x8ExtMulHighI8x16U) \
  V(I16x8Shl)              \
  V(I16x8ShrS)             \
  V(I16x8ShrU)             \
  V(I8x16Add)              \
  V(I8x16Sub)              \
  V(I8x16MinS)             \
  V(I8x16MinU)             \
  V(I8x16MaxS)             \
  V(I8x16MaxU)             \
  V(I8x16Eq)               \
  V(I8x16Ne)               \
  V(I8x16GtS)              \
  V(I8x16GeS)              \
  V(I8x16GtU)              \
  V(I8x16GeU)              \
  V(I8x16SConvertI16x8)    \
  V(I8x16UConvertI16x8)    \
  V(I8x16RoundingAverageU) \
  V(I8x16Shl)              \
  V(I8x16ShrS)             \
  V(I8x16ShrU)             \
  V(S128And)               \
  V(S128Or)                \
  V(S128Xor)               \
  V(S128AndNot)
 
#define SIMD_BINOP_UNIQUE_REGISTER_LIST(V) \
  V(I16x8AddSatS)                          \
  V(I16x8SubSatS)                          \
  V(I16x8AddSatU)                          \
  V(I16x8SubSatU)                          \
  V(I16x8Q15MulRSatS)                      \
  V(I8x16AddSatS)                          \
  V(I8x16SubSatS)                          \
  V(I8x16AddSatU)                          \
  V(I8x16SubSatU)
 
#define SIMD_UNOP_LIST(V)    \
  V(F64x2Abs)                \
  V(F64x2Neg)                \
  V(F64x2Sqrt)               \
  V(F64x2Ceil)               \
  V(F64x2Floor)              \
  V(F64x2Trunc)              \
  V(F64x2NearestInt)         \
  V(F64x2ConvertLowI32x4S)   \
  V(F64x2ConvertLowI32x4U)   \
  V(F64x2PromoteLowF32x4)    \
  V(F64x2Splat)              \
  V(F32x4Abs)                \
  V(F32x4Neg)                \
  V(F32x4Sqrt)               \
  V(F32x4Ceil)               \
  V(F32x4Floor)              \
  V(F32x4Trunc)              \
  V(F32x4NearestInt)         \
  V(F32x4DemoteF64x2Zero)    \
  V(F32x4SConvertI32x4)      \
  V(F32x4UConvertI32x4)      \
  V(F32x4Splat)              \
  V(I64x2Neg)                \
  V(I64x2SConvertI32x4Low)   \
  V(I64x2SConvertI32x4High)  \
  V(I64x2UConvertI32x4Low)   \
  V(I64x2UConvertI32x4High)  \
  V(I64x2Abs)                \
  V(I64x2BitMask)            \
  V(I64x2Splat)              \
  V(I64x2AllTrue)            \
  V(I32x4Neg)                \
  V(I32x4Abs)                \
  V(I32x4SConvertF32x4)      \
  V(I32x4UConvertF32x4)      \
  V(I32x4SConvertI16x8Low)   \
  V(I32x4SConvertI16x8High)  \
  V(I32x4UConvertI16x8Low)   \
  V(I32x4UConvertI16x8High)  \
  V(I32x4TruncSatF64x2SZero) \
  V(I32x4TruncSatF64x2UZero) \
  V(I32x4BitMask)            \
  V(I32x4Splat)              \
  V(I32x4AllTrue)            \
  V(I16x8Neg)                \
  V(I16x8Abs)                \
  V(I16x8SConvertI8x16Low)   \
  V(I16x8SConvertI8x16High)  \
  V(I16x8UConvertI8x16Low)   \
  V(I16x8UConvertI8x16High)  \
  V(I16x8BitMask)            \
  V(I16x8Splat)              \
  V(I16x8AllTrue)            \
  V(I8x16Neg)                \
  V(I8x16Abs)                \
  V(I8x16Popcnt)             \
  V(I8x16BitMask)            \
  V(I8x16Splat)              \
  V(I8x16AllTrue)            \
  V(S128Not)                 \
  V(V128AnyTrue)
 
#define SIMD_UNOP_UNIQUE_REGISTER_LIST(V) \
  V(I32x4ExtAddPairwiseI16x8S)            \
  V(I32x4ExtAddPairwiseI16x8U)            \
  V(I16x8ExtAddPairwiseI8x16S)            \
  V(I16x8ExtAddPairwiseI8x16U)
 
#define SIMD_VISIT_EXTRACT_LANE(Type, Sign)                                 \
  void InstructionSelectorT::Visit##Type##ExtractLane##Sign(OpIndex node) { \
    S390OperandGeneratorT g(this);                                          \
    int32_t lane;                                                           \
    using namespace turboshaft; /* NOLINT(build/namespaces) */              \
    const Operation& op = this->Get(node);                                  \
    lane = op.template Cast<Simd128ExtractLaneOp>().lane;                   \
    Emit(kS390_##Type##ExtractLane##Sign, g.DefineAsRegister(node),         \
         g.UseRegister(this->input_at(node, 0)), g.UseImmediate(lane));     \
  }
SIMD_VISIT_EXTRACT_LANE(F64x2, )
SIMD_VISIT_EXTRACT_LANE(F32x4, )
SIMD_VISIT_EXTRACT_LANE(I64x2, )
SIMD_VISIT_EXTRACT_LANE(I32x4, )
SIMD_VISIT_EXTRACT_LANE(I16x8, U)
SIMD_VISIT_EXTRACT_LANE(I16x8, S)
SIMD_VISIT_EXTRACT_LANE(I8x16, U)
SIMD_VISIT_EXTRACT_LANE(I8x16, S)
#undef SIMD_VISIT_EXTRACT_LANE
 
#define SIMD_VISIT_REPLACE_LANE(Type)                                  \
  void InstructionSelectorT::Visit##Type##ReplaceLane(OpIndex node) {  \
    S390OperandGeneratorT g(this);                                     \
    int32_t lane;                                                      \
    using namespace turboshaft; /* NOLINT(build/namespaces) */         \
    const Operation& op = this->Get(node);                             \
    lane = op.template Cast<Simd128ReplaceLaneOp>().lane;              \
    Emit(kS390_##Type##ReplaceLane, g.DefineAsRegister(node),          \
         g.UseRegister(this->input_at(node, 0)), g.UseImmediate(lane), \
         g.UseRegister(this->input_at(node, 1)));                      \
  }
SIMD_TYPES(SIMD_VISIT_REPLACE_LANE)
#undef SIMD_VISIT_REPLACE_LANE
 
#define SIMD_VISIT_BINOP(Opcode)                           \
  void InstructionSelectorT::Visit##Opcode(OpIndex node) { \
    S390OperandGeneratorT g(this);                         \
    Emit(kS390_##Opcode, g.DefineAsRegister(node),         \
         g.UseRegister(this->input_at(node, 0)),           \
         g.UseRegister(this->input_at(node, 1)));          \
  }
SIMD_BINOP_LIST(SIMD_VISIT_BINOP)
#undef SIMD_VISIT_BINOP
#undef SIMD_BINOP_LIST
 
#define SIMD_VISIT_BINOP_UNIQUE_REGISTER(Opcode)                         \
  void InstructionSelectorT::Visit##Opcode(OpIndex node) {               \
    S390OperandGeneratorT g(this);                                       \
    InstructionOperand temps[] = {g.TempSimd128Register(),               \
                                  g.TempSimd128Register()};              \
    Emit(kS390_##Opcode, g.DefineAsRegister(node),                       \
         g.UseUniqueRegister(this->input_at(node, 0)),                   \
         g.UseUniqueRegister(this->input_at(node, 1)), arraysize(temps), \
         temps);                                                         \
  }
SIMD_BINOP_UNIQUE_REGISTER_LIST(SIMD_VISIT_BINOP_UNIQUE_REGISTER)
#undef SIMD_VISIT_BINOP_UNIQUE_REGISTER
#undef SIMD_BINOP_UNIQUE_REGISTER_LIST
 
#define SIMD_VISIT_UNOP(Opcode)                            \
  void InstructionSelectorT::Visit##Opcode(OpIndex node) { \
    S390OperandGeneratorT g(this);                         \
    Emit(kS390_##Opcode, g.DefineAsRegister(node),         \
         g.UseRegister(this->input_at(node, 0)));          \
  }
SIMD_UNOP_LIST(SIMD_VISIT_UNOP)
#undef SIMD_VISIT_UNOP
#undef SIMD_UNOP_LIST
 
#define SIMD_VISIT_UNOP_UNIQUE_REGISTER(Opcode)                          \
  void InstructionSelectorT::Visit##Opcode(OpIndex node) {               \
    S390OperandGeneratorT g(this);                                       \
    InstructionOperand temps[] = {g.TempSimd128Register()};              \
    Emit(kS390_##Opcode, g.DefineAsRegister(node),                       \
         g.UseUniqueRegister(this->input_at(node, 0)), arraysize(temps), \
         temps);                                                         \
  }
SIMD_UNOP_UNIQUE_REGISTER_LIST(SIMD_VISIT_UNOP_UNIQUE_REGISTER)
#undef SIMD_VISIT_UNOP_UNIQUE_REGISTER
#undef SIMD_UNOP_UNIQUE_REGISTER_LIST
 
#define SIMD_VISIT_QFMOP(Opcode)                           \
  void InstructionSelectorT::Visit##Opcode(OpIndex node) { \
    S390OperandGeneratorT g(this);                         \
    Emit(kS390_##Opcode, g.DefineSameAsFirst(node),        \
         g.UseRegister(this->input_at(node, 0)),           \
         g.UseRegister(this->input_at(node, 1)),           \
         g.UseRegister(this->input_at(node, 2)));          \
  }
SIMD_VISIT_QFMOP(F64x2Qfma)
SIMD_VISIT_QFMOP(F64x2Qfms)
SIMD_VISIT_QFMOP(F32x4Qfma)
SIMD_VISIT_QFMOP(F32x4Qfms)
#undef SIMD_VISIT_QFMOP
 
#define SIMD_RELAXED_OP_LIST(V)                           \
  V(F64x2RelaxedMin, F64x2Pmin)                           \
  V(F64x2RelaxedMax, F64x2Pmax)                           \
  V(F32x4RelaxedMin, F32x4Pmin)                           \
  V(F32x4RelaxedMax, F32x4Pmax)                           \
  V(I32x4RelaxedTruncF32x4S, I32x4SConvertF32x4)          \
  V(I32x4RelaxedTruncF32x4U, I32x4UConvertF32x4)          \
  V(I32x4RelaxedTruncF64x2SZero, I32x4TruncSatF64x2SZero) \
  V(I32x4RelaxedTruncF64x2UZero, I32x4TruncSatF64x2UZero) \
  V(I16x8RelaxedQ15MulRS, I16x8Q15MulRSatS)               \
  V(I8x16RelaxedLaneSelect, S128Select)                   \
  V(I16x8RelaxedLaneSelect, S128Select)                   \
  V(I32x4RelaxedLaneSelect, S128Select)                   \
  V(I64x2RelaxedLaneSelect, S128Select)
 
#define SIMD_VISIT_RELAXED_OP(name, op) \
  void InstructionSelectorT::Visit##name(OpIndex node) { Visit##op(node); }
SIMD_RELAXED_OP_LIST(SIMD_VISIT_RELAXED_OP)
#undef SIMD_VISIT_RELAXED_OP
#undef SIMD_RELAXED_OP_LIST
 
#define F16_OP_LIST(V)    \
  V(F16x8Splat)           \
  V(F16x8ExtractLane)     \
  V(F16x8ReplaceLane)     \
  V(F16x8Abs)             \
  V(F16x8Neg)             \
  V(F16x8Sqrt)            \
  V(F16x8Floor)           \
  V(F16x8Ceil)            \
  V(F16x8Trunc)           \
  V(F16x8NearestInt)      \
  V(F16x8Add)             \
  V(F16x8Sub)             \
  V(F16x8Mul)             \
  V(F16x8Div)             \
  V(F16x8Min)             \
  V(F16x8Max)             \
  V(F16x8Pmin)            \
  V(F16x8Pmax)            \
  V(F16x8Eq)              \
  V(F16x8Ne)              \
  V(F16x8Lt)              \
  V(F16x8Le)              \
  V(F16x8SConvertI16x8)   \
  V(F16x8UConvertI16x8)   \
  V(I16x8SConvertF16x8)   \
  V(I16x8UConvertF16x8)   \
  V(F32x4PromoteLowF16x8) \
  V(F16x8DemoteF32x4Zero) \
  V(F16x8DemoteF64x2Zero) \
  V(F16x8Qfma)            \
  V(F16x8Qfms)
 
#define VISIT_F16_OP(name) \
  void InstructionSelectorT::Visit##name(OpIndex node) { UNIMPLEMENTED(); }
F16_OP_LIST(VISIT_F16_OP)
#undef VISIT_F16_OP
#undef F16_OP_LIST
#undef SIMD_TYPES
 
#if V8_ENABLE_WEBASSEMBLY
void InstructionSelectorT::VisitI8x16Shuffle(OpIndex node) {
  uint8_t shuffle[kSimd128Size];
  bool is_swizzle;
  // TODO(nicohartmann@): Properly use view here once Turboshaft support is
  // implemented.
  auto view = this->simd_shuffle_view(node);
  CanonicalizeShuffle(view, shuffle, &is_swizzle);
  S390OperandGeneratorT g(this);
  OpIndex input0 = view.input(0);
  OpIndex input1 = view.input(1);
  // Remap the shuffle indices to match IBM lane numbering.
  int max_index = 15;
  int total_lane_count = 2 * kSimd128Size;
  uint8_t shuffle_remapped[kSimd128Size];
  for (int i = 0; i < kSimd128Size; i++) {
    uint8_t current_index = shuffle[i];
    shuffle_remapped[i] = (current_index <= max_index
                               ? max_index - current_index
                               : total_lane_count - current_index + max_index);
  }
  Emit(kS390_I8x16Shuffle, g.DefineAsRegister(node), g.UseRegister(input0),
       g.UseRegister(input1),
       g.UseImmediate(wasm::SimdShuffle::Pack4Lanes(shuffle_remapped)),
       g.UseImmediate(wasm::SimdShuffle::Pack4Lanes(shuffle_remapped + 4)),
       g.UseImmediate(wasm::SimdShuffle::Pack4Lanes(shuffle_remapped + 8)),
       g.UseImmediate(wasm::SimdShuffle::Pack4Lanes(shuffle_remapped + 12)));
}
 
void InstructionSelectorT::VisitI8x16Swizzle(OpIndex node) {
  S390OperandGeneratorT g(this);
  bool relaxed;
  const Simd128BinopOp& binop = this->Get(node).template Cast<Simd128BinopOp>();
  DCHECK(binop.kind == any_of(Simd128BinopOp::Kind::kI8x16Swizzle,
                              Simd128BinopOp::Kind::kI8x16RelaxedSwizzle));
  relaxed = binop.kind == Simd128BinopOp::Kind::kI8x16RelaxedSwizzle;
  // TODO(miladfarca): Optimize Swizzle if relaxed.
  USE(relaxed);
 
  Emit(kS390_I8x16Swizzle, g.DefineAsRegister(node),
       g.UseUniqueRegister(this->input_at(node, 0)),
       g.UseUniqueRegister(this->input_at(node, 1)));
}
 
void InstructionSelectorT::VisitSetStackPointer(OpIndex node) {
  OperandGenerator g(this);
  // TODO(miladfarca): Optimize by using UseAny.
  auto input = g.UseRegister(this->input_at(node, 0));
  Emit(kArchSetStackPointer, 0, nullptr, 1, &input);
}
 
#else
void InstructionSelectorT::VisitI8x16Shuffle(OpIndex node) { UNREACHABLE(); }
void InstructionSelectorT::VisitI8x16Swizzle(OpIndex node) { UNREACHABLE(); }
#endif  // V8_ENABLE_WEBASSEMBLY
 
// This is a replica of SimdShuffle::Pack4Lanes. However, above function will
// not be available on builds with webassembly disabled, hence we need to have
// it declared locally as it is used on other visitors such as S128Const.
static int32_t Pack4Lanes(const uint8_t* shuffle) {
  int32_t result = 0;
  for (int i = 3; i >= 0; --i) {
    result <<= 8;
    result |= shuffle[i];
  }
  return result;
}
 
void InstructionSelectorT::VisitS128Const(OpIndex node) {
  S390OperandGeneratorT g(this);
  uint32_t val[kSimd128Size / sizeof(uint32_t)];
  const Simd128ConstantOp& constant =
      this->Get(node).template Cast<Simd128ConstantOp>();
  memcpy(val, constant.value, kSimd128Size);
  // If all bytes are zeros, avoid emitting code for generic constants.
  bool all_zeros = !(val[0] || val[1] || val[2] || val[3]);
  bool all_ones = val[0] == UINT32_MAX && val[1] == UINT32_MAX &&
                  val[2] == UINT32_MAX && val[3] == UINT32_MAX;
  InstructionOperand dst = g.DefineAsRegister(node);
  if (all_zeros) {
    Emit(kS390_S128Zero, dst);
  } else if (all_ones) {
    Emit(kS390_S128AllOnes, dst);
  } else {
    // We have to use Pack4Lanes to reverse the bytes (lanes) on BE,
    // Which in this case is ineffective on LE.
    Emit(kS390_S128Const, dst,
         g.UseImmediate(Pack4Lanes(reinterpret_cast<uint8_t*>(&val[0]))),
         g.UseImmediate(Pack4Lanes(reinterpret_cast<uint8_t*>(&val[0]) + 4)),
         g.UseImmediate(Pack4Lanes(reinterpret_cast<uint8_t*>(&val[0]) + 8)),
         g.UseImmediate(Pack4Lanes(reinterpret_cast<uint8_t*>(&val[0]) + 12)));
  }
}
 
void InstructionSelectorT::VisitS128Zero(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kS390_S128Zero, g.DefineAsRegister(node));
}
 
void InstructionSelectorT::VisitS128Select(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kS390_S128Select, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)),
       g.UseRegister(this->input_at(node, 1)),
       g.UseRegister(this->input_at(node, 2)));
}
 
void InstructionSelectorT::EmitPrepareResults(
    ZoneVector<PushParameter>* results, const CallDescriptor* call_descriptor,
    OpIndex node) {
  S390OperandGeneratorT g(this);
 
  for (PushParameter output : *results) {
    if (!output.location.IsCallerFrameSlot()) continue;
    // Skip any alignment holes in nodes.
    if (output.node.valid()) {
      DCHECK(!call_descriptor->IsCFunctionCall());
      if (output.location.GetType() == MachineType::Float32()) {
        MarkAsFloat32(output.node);
      } else if (output.location.GetType() == MachineType::Float64()) {
        MarkAsFloat64(output.node);
      } else if (output.location.GetType() == MachineType::Simd128()) {
        MarkAsSimd128(output.node);
      }
      int offset = call_descriptor->GetOffsetToReturns();
      int reverse_slot = -output.location.GetLocation() - offset;
      Emit(kS390_Peek, g.DefineAsRegister(output.node),
           g.UseImmediate(reverse_slot));
    }
  }
}
 
void InstructionSelectorT::VisitLoadLane(OpIndex node) {
  InstructionCode opcode;
  int32_t lane;
    const Simd128LaneMemoryOp& load =
        this->Get(node).template Cast<Simd128LaneMemoryOp>();
    lane = load.lane;
    switch (load.lane_kind) {
      case Simd128LaneMemoryOp::LaneKind::k8:
        opcode = kS390_S128Load8Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k16:
        opcode = kS390_S128Load16Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k32:
        opcode = kS390_S128Load32Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k64:
        opcode = kS390_S128Load64Lane;
        break;
    }
    S390OperandGeneratorT g(this);
    InstructionOperand outputs[] = {g.DefineSameAsFirst(node)};
    InstructionOperand inputs[5];
    size_t input_count = 0;
 
    inputs[input_count++] = g.UseRegister(this->input_at(node, 2));
    inputs[input_count++] = g.UseImmediate(lane);
 
    AddressingMode mode =
        g.GetEffectiveAddressMemoryOperand(node, inputs, &input_count);
    opcode |= AddressingModeField::encode(mode);
    Emit(opcode, 1, outputs, input_count, inputs);
}
 
void InstructionSelectorT::VisitLoadTransform(OpIndex node) {
  ArchOpcode opcode;
    const Simd128LoadTransformOp& op =
        this->Get(node).template Cast<Simd128LoadTransformOp>();
    switch (op.transform_kind) {
      case Simd128LoadTransformOp::TransformKind::k8Splat:
        opcode = kS390_S128Load8Splat;
        break;
      case Simd128LoadTransformOp::TransformKind::k16Splat:
        opcode = kS390_S128Load16Splat;
        break;
      case Simd128LoadTransformOp::TransformKind::k32Splat:
        opcode = kS390_S128Load32Splat;
        break;
      case Simd128LoadTransformOp::TransformKind::k64Splat:
        opcode = kS390_S128Load64Splat;
        break;
      case Simd128LoadTransformOp::TransformKind::k8x8S:
        opcode = kS390_S128Load8x8S;
        break;
      case Simd128LoadTransformOp::TransformKind::k8x8U:
        opcode = kS390_S128Load8x8U;
        break;
      case Simd128LoadTransformOp::TransformKind::k16x4S:
        opcode = kS390_S128Load16x4S;
        break;
      case Simd128LoadTransformOp::TransformKind::k16x4U:
        opcode = kS390_S128Load16x4U;
        break;
      case Simd128LoadTransformOp::TransformKind::k32x2S:
        opcode = kS390_S128Load32x2S;
        break;
      case Simd128LoadTransformOp::TransformKind::k32x2U:
        opcode = kS390_S128Load32x2U;
        break;
      case Simd128LoadTransformOp::TransformKind::k32Zero:
        opcode = kS390_S128Load32Zero;
        break;
      case Simd128LoadTransformOp::TransformKind::k64Zero:
        opcode = kS390_S128Load64Zero;
        break;
      default:
        UNIMPLEMENTED();
    }
  VisitLoad(node, node, opcode);
}
 
void InstructionSelectorT::VisitStoreLane(OpIndex node) {
  InstructionCode opcode = kArchNop;
  int32_t lane;
    const Simd128LaneMemoryOp& store =
        this->Get(node).template Cast<Simd128LaneMemoryOp>();
    lane = store.lane;
    switch (store.lane_kind) {
      case Simd128LaneMemoryOp::LaneKind::k8:
        opcode = kS390_S128Store8Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k16:
        opcode = kS390_S128Store16Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k32:
        opcode = kS390_S128Store32Lane;
        break;
      case Simd128LaneMemoryOp::LaneKind::k64:
        opcode = kS390_S128Store64Lane;
        break;
    }
    S390OperandGeneratorT g(this);
    InstructionOperand inputs[5];
    size_t input_count = 0;
 
    inputs[input_count++] = g.UseRegister(this->input_at(node, 2));
    inputs[input_count++] = g.UseImmediate(lane);
 
    AddressingMode mode =
        g.GetEffectiveAddressMemoryOperand(node, inputs, &input_count);
    opcode |= AddressingModeField::encode(mode);
    Emit(opcode, 0, nullptr, input_count, inputs);
}
 
void InstructionSelectorT::VisitI16x8DotI8x16I7x16S(OpIndex node) {
  S390OperandGeneratorT g(this);
  Emit(kS390_I16x8DotI8x16S, g.DefineAsRegister(node),
       g.UseUniqueRegister(this->input_at(node, 0)),
       g.UseUniqueRegister(this->input_at(node, 1)));
}
 
void InstructionSelectorT::VisitI32x4DotI8x16I7x16AddS(OpIndex node) {
  S390OperandGeneratorT g(this);
  InstructionOperand temps[] = {g.TempSimd128Register()};
  Emit(kS390_I32x4DotI8x16AddS, g.DefineAsRegister(node),
       g.UseUniqueRegister(this->input_at(node, 0)),
       g.UseUniqueRegister(this->input_at(node, 1)),
       g.UseUniqueRegister(this->input_at(node, 2)), arraysize(temps), temps);
}
 
void InstructionSelectorT::VisitTruncateFloat32ToInt32(OpIndex node) {
  S390OperandGeneratorT g(this);
  const Operation& op = this->Get(node);
  InstructionCode opcode = kS390_Float32ToInt32;
  if (op.Is<Opmask::kTruncateFloat32ToInt32OverflowToMin>()) {
    opcode |= MiscField::encode(true);
  }
  Emit(opcode, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)));
}
 
void InstructionSelectorT::VisitTruncateFloat32ToUint32(OpIndex node) {
  S390OperandGeneratorT g(this);
  const Operation& op = this->Get(node);
  InstructionCode opcode = kS390_Float32ToUint32;
  if (op.Is<Opmask::kTruncateFloat32ToUint32OverflowToMin>()) {
    opcode |= MiscField::encode(true);
  }
 
  Emit(opcode, g.DefineAsRegister(node),
       g.UseRegister(this->input_at(node, 0)));
}
 
void InstructionSelectorT::AddOutputToSelectContinuation(OperandGenerator* g,
                                                         int first_input_index,
                                                         OpIndex node) {
  UNREACHABLE();
}
 
MachineOperatorBuilder::Flags
InstructionSelector::SupportedMachineOperatorFlags() {
  return MachineOperatorBuilder::kFloat32RoundDown |
         MachineOperatorBuilder::kFloat64RoundDown |
         MachineOperatorBuilder::kFloat32RoundUp |
         MachineOperatorBuilder::kFloat64RoundUp |
         MachineOperatorBuilder::kFloat32RoundTruncate |
         MachineOperatorBuilder::kFloat64RoundTruncate |
         MachineOperatorBuilder::kFloat32RoundTiesEven |
         MachineOperatorBuilder::kFloat64RoundTiesEven |
         MachineOperatorBuilder::kFloat64RoundTiesAway |
         MachineOperatorBuilder::kWord32Popcnt |
         MachineOperatorBuilder::kInt32AbsWithOverflow |
         MachineOperatorBuilder::kInt64AbsWithOverflow |
         MachineOperatorBuilder::kWord64Popcnt;
}
 
MachineOperatorBuilder::AlignmentRequirements
InstructionSelector::AlignmentRequirements() {
  return MachineOperatorBuilder::AlignmentRequirements::
      FullUnalignedAccessSupport();
}
 
}  // namespace compiler
}  // namespace internal
}  // namespace v8