mozjs_sys 0.67.1

System crate for the Mozilla SpiderMonkey JavaScript engine.
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/* -*- 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_mips_shared_SharedICHelpers_mips_shared_inl_h
#define jit_mips_shared_SharedICHelpers_mips_shared_inl_h

#include "jit/SharedICHelpers.h"

#include "jit/MacroAssembler-inl.h"

namespace js {
namespace jit {

inline void EmitBaselineTailCallVM(TrampolinePtr target, MacroAssembler& masm,
                                   uint32_t argSize) {
  Register scratch = R2.scratchReg();

  // Compute frame size.
  masm.movePtr(BaselineFrameReg, scratch);
  masm.addPtr(Imm32(BaselineFrame::FramePointerOffset), scratch);
  masm.subPtr(BaselineStackReg, scratch);

  // Store frame size without VMFunction arguments for GC marking.
  masm.subPtr(Imm32(argSize), scratch);
  masm.store32(scratch, Address(BaselineFrameReg,
                                BaselineFrame::reverseOffsetOfFrameSize()));
  masm.addPtr(Imm32(argSize), scratch);

  // Push frame descriptor and perform the tail call.
  // ICTailCallReg (ra) already contains the return address (as we
  // keep it there through the stub calls), but the VMWrapper code being
  // called expects the return address to also be pushed on the stack.
  MOZ_ASSERT(ICTailCallReg == ra);
  masm.makeFrameDescriptor(scratch, FrameType::BaselineJS,
                           ExitFrameLayout::Size());
  masm.subPtr(Imm32(sizeof(CommonFrameLayout)), StackPointer);
  masm.storePtr(scratch,
                Address(StackPointer, CommonFrameLayout::offsetOfDescriptor()));
  masm.storePtr(
      ra, Address(StackPointer, CommonFrameLayout::offsetOfReturnAddress()));

  masm.jump(target);
}

inline void EmitBaselineCreateStubFrameDescriptor(MacroAssembler& masm,
                                                  Register reg,
                                                  uint32_t headerSize) {
  // Compute stub frame size. We have to add two pointers: the stub reg and
  // previous frame pointer pushed by EmitEnterStubFrame.
  masm.movePtr(BaselineFrameReg, reg);
  masm.addPtr(Imm32(sizeof(intptr_t) * 2), reg);
  masm.subPtr(BaselineStackReg, reg);

  masm.makeFrameDescriptor(reg, FrameType::BaselineStub, headerSize);
}

inline void EmitBaselineCallVM(TrampolinePtr target, MacroAssembler& masm) {
  Register scratch = R2.scratchReg();
  EmitBaselineCreateStubFrameDescriptor(masm, scratch, ExitFrameLayout::Size());
  masm.push(scratch);
  masm.call(target);
}

inline void EmitBaselineEnterStubFrame(MacroAssembler& masm, Register scratch) {
  MOZ_ASSERT(scratch != ICTailCallReg);

  // Compute frame size.
  masm.movePtr(BaselineFrameReg, scratch);
  masm.addPtr(Imm32(BaselineFrame::FramePointerOffset), scratch);
  masm.subPtr(BaselineStackReg, scratch);

  masm.store32(scratch, Address(BaselineFrameReg,
                                BaselineFrame::reverseOffsetOfFrameSize()));

  // Note: when making changes here, don't forget to update
  // BaselineStubFrame if needed.

  // Push frame descriptor and return address.
  masm.makeFrameDescriptor(scratch, FrameType::BaselineJS,
                           BaselineStubFrameLayout::Size());
  masm.subPtr(Imm32(STUB_FRAME_SIZE), StackPointer);
  masm.storePtr(scratch,
                Address(StackPointer, offsetof(BaselineStubFrame, descriptor)));
  masm.storePtr(ICTailCallReg, Address(StackPointer, offsetof(BaselineStubFrame,
                                                              returnAddress)));

  // Save old frame pointer, stack pointer and stub reg.
  masm.storePtr(ICStubReg,
                Address(StackPointer, offsetof(BaselineStubFrame, savedStub)));
  masm.storePtr(BaselineFrameReg,
                Address(StackPointer, offsetof(BaselineStubFrame, savedFrame)));
  masm.movePtr(BaselineStackReg, BaselineFrameReg);

  // Stack should remain aligned.
  masm.assertStackAlignment(sizeof(Value), 0);
}

}  // namespace jit
}  // namespace js

#endif /* jit_mips_shared_SharedICHelpers_mips_shared_inl_h */