mozjs_sys 0.67.1

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: set ts=8 sts=2 et sw=2 tw=80:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef jit_x86_shared_CodeGenerator_x86_shared_h
#define jit_x86_shared_CodeGenerator_x86_shared_h

#include "jit/shared/CodeGenerator-shared.h"

namespace js {
namespace jit {

class CodeGeneratorX86Shared;
class OutOfLineBailout;
class OutOfLineUndoALUOperation;
class OutOfLineLoadTypedArrayOutOfBounds;
class MulNegativeZeroCheck;
class ModOverflowCheck;
class ReturnZero;
class OutOfLineTableSwitch;

using OutOfLineWasmTruncateCheck =
    OutOfLineWasmTruncateCheckBase<CodeGeneratorX86Shared>;

class CodeGeneratorX86Shared : public CodeGeneratorShared {
  friend class MoveResolverX86;

  template <typename T>
  void bailout(const T& t, LSnapshot* snapshot);

 protected:
  CodeGeneratorX86Shared(MIRGenerator* gen, LIRGraph* graph,
                         MacroAssembler* masm);

  // Load a NaN or zero into a register for an out of bounds AsmJS or static
  // typed array load.
  class OutOfLineLoadTypedArrayOutOfBounds
      : public OutOfLineCodeBase<CodeGeneratorX86Shared> {
    AnyRegister dest_;
    Scalar::Type viewType_;

   public:
    OutOfLineLoadTypedArrayOutOfBounds(AnyRegister dest, Scalar::Type viewType)
        : dest_(dest), viewType_(viewType) {}

    AnyRegister dest() const { return dest_; }
    Scalar::Type viewType() const { return viewType_; }
    void accept(CodeGeneratorX86Shared* codegen) override {
      codegen->visitOutOfLineLoadTypedArrayOutOfBounds(this);
    }
  };

  NonAssertingLabel deoptLabel_;

  Operand ToOperand(const LAllocation& a);
  Operand ToOperand(const LAllocation* a);
  Operand ToOperand(const LDefinition* def);

#ifdef JS_PUNBOX64
  Operand ToOperandOrRegister64(const LInt64Allocation input);
#else
  Register64 ToOperandOrRegister64(const LInt64Allocation input);
#endif

  MoveOperand toMoveOperand(LAllocation a) const;

  void bailoutIf(Assembler::Condition condition, LSnapshot* snapshot);
  void bailoutIf(Assembler::DoubleCondition condition, LSnapshot* snapshot);
  void bailoutFrom(Label* label, LSnapshot* snapshot);
  void bailout(LSnapshot* snapshot);

  template <typename T1, typename T2>
  void bailoutCmpPtr(Assembler::Condition c, T1 lhs, T2 rhs,
                     LSnapshot* snapshot) {
    masm.cmpPtr(lhs, rhs);
    bailoutIf(c, snapshot);
  }
  void bailoutTestPtr(Assembler::Condition c, Register lhs, Register rhs,
                      LSnapshot* snapshot) {
    masm.testPtr(lhs, rhs);
    bailoutIf(c, snapshot);
  }
  template <typename T1, typename T2>
  void bailoutCmp32(Assembler::Condition c, T1 lhs, T2 rhs,
                    LSnapshot* snapshot) {
    masm.cmp32(lhs, rhs);
    bailoutIf(c, snapshot);
  }
  template <typename T1, typename T2>
  void bailoutTest32(Assembler::Condition c, T1 lhs, T2 rhs,
                     LSnapshot* snapshot) {
    masm.test32(lhs, rhs);
    bailoutIf(c, snapshot);
  }
  void bailoutIfFalseBool(Register reg, LSnapshot* snapshot) {
    masm.test32(reg, Imm32(0xFF));
    bailoutIf(Assembler::Zero, snapshot);
  }
  void bailoutCvttsd2si(FloatRegister src, Register dest, LSnapshot* snapshot) {
    // vcvttsd2si returns 0x80000000 on failure. Test for it by
    // subtracting 1 and testing overflow. The other possibility is to test
    // equality for INT_MIN after a comparison, but 1 costs fewer bytes to
    // materialize.
    masm.vcvttsd2si(src, dest);
    masm.cmp32(dest, Imm32(1));
    bailoutIf(Assembler::Overflow, snapshot);
  }
  void bailoutCvttss2si(FloatRegister src, Register dest, LSnapshot* snapshot) {
    // Same trick as explained in the above comment.
    masm.vcvttss2si(src, dest);
    masm.cmp32(dest, Imm32(1));
    bailoutIf(Assembler::Overflow, snapshot);
  }

  bool generateOutOfLineCode();

  void emitCompare(MCompare::CompareType type, const LAllocation* left,
                   const LAllocation* right);

  // Emits a branch that directs control flow to the true block if |cond| is
  // true, and the false block if |cond| is false.
  void emitBranch(Assembler::Condition cond, MBasicBlock* ifTrue,
                  MBasicBlock* ifFalse,
                  Assembler::NaNCond ifNaN = Assembler::NaN_HandledByCond);
  void emitBranch(Assembler::DoubleCondition cond, MBasicBlock* ifTrue,
                  MBasicBlock* ifFalse);

  void testNullEmitBranch(Assembler::Condition cond, const ValueOperand& value,
                          MBasicBlock* ifTrue, MBasicBlock* ifFalse) {
    cond = masm.testNull(cond, value);
    emitBranch(cond, ifTrue, ifFalse);
  }
  void testUndefinedEmitBranch(Assembler::Condition cond,
                               const ValueOperand& value, MBasicBlock* ifTrue,
                               MBasicBlock* ifFalse) {
    cond = masm.testUndefined(cond, value);
    emitBranch(cond, ifTrue, ifFalse);
  }
  void testObjectEmitBranch(Assembler::Condition cond,
                            const ValueOperand& value, MBasicBlock* ifTrue,
                            MBasicBlock* ifFalse) {
    cond = masm.testObject(cond, value);
    emitBranch(cond, ifTrue, ifFalse);
  }

  void testZeroEmitBranch(Assembler::Condition cond, Register reg,
                          MBasicBlock* ifTrue, MBasicBlock* ifFalse) {
    MOZ_ASSERT(cond == Assembler::Equal || cond == Assembler::NotEqual);
    masm.cmpPtr(reg, ImmWord(0));
    emitBranch(cond, ifTrue, ifFalse);
  }

  void emitTableSwitchDispatch(MTableSwitch* mir, Register index,
                               Register base);

  void generateInvalidateEpilogue();

  void canonicalizeIfDeterministic(Scalar::Type type, const LAllocation* value);

 public:
  // Out of line visitors.
  void visitOutOfLineBailout(OutOfLineBailout* ool);
  void visitOutOfLineUndoALUOperation(OutOfLineUndoALUOperation* ool);
  void visitMulNegativeZeroCheck(MulNegativeZeroCheck* ool);
  void visitModOverflowCheck(ModOverflowCheck* ool);
  void visitReturnZero(ReturnZero* ool);
  void visitOutOfLineTableSwitch(OutOfLineTableSwitch* ool);
  void visitOutOfLineLoadTypedArrayOutOfBounds(
      OutOfLineLoadTypedArrayOutOfBounds* ool);
  void visitOutOfLineWasmTruncateCheck(OutOfLineWasmTruncateCheck* ool);
};

// An out-of-line bailout thunk.
class OutOfLineBailout : public OutOfLineCodeBase<CodeGeneratorX86Shared> {
  LSnapshot* snapshot_;

 public:
  explicit OutOfLineBailout(LSnapshot* snapshot) : snapshot_(snapshot) {}

  void accept(CodeGeneratorX86Shared* codegen) override;

  LSnapshot* snapshot() const { return snapshot_; }
};

}  // namespace jit
}  // namespace js

#endif /* jit_x86_shared_CodeGenerator_x86_shared_h */