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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_x86_SharedICHelpers_x86_inl_h
#define jit_x86_SharedICHelpers_x86_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) {
// We assume during this that R0 and R1 have been pushed.
// Compute frame size.
masm.movl(BaselineFrameReg, eax);
masm.addl(Imm32(BaselineFrame::FramePointerOffset), eax);
masm.subl(BaselineStackReg, eax);
// Store frame size without VMFunction arguments for GC marking.
masm.movl(eax, ebx);
masm.subl(Imm32(argSize), ebx);
masm.store32(ebx, Address(BaselineFrameReg,
BaselineFrame::reverseOffsetOfFrameSize()));
// Push frame descriptor and perform the tail call.
masm.makeFrameDescriptor(eax, FrameType::BaselineJS, ExitFrameLayout::Size());
masm.push(eax);
masm.push(ICTailCallReg);
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.movl(BaselineFrameReg, reg);
masm.addl(Imm32(sizeof(void*) * 2), reg);
masm.subl(BaselineStackReg, reg);
masm.makeFrameDescriptor(reg, FrameType::BaselineStub, headerSize);
}
inline void EmitBaselineCallVM(TrampolinePtr target, MacroAssembler& masm) {
EmitBaselineCreateStubFrameDescriptor(masm, eax, ExitFrameLayout::Size());
masm.push(eax);
masm.call(target);
}
// Size of values pushed by EmitBaselineEnterStubFrame.
static const uint32_t STUB_FRAME_SIZE = 4 * sizeof(void*);
static const uint32_t STUB_FRAME_SAVED_STUB_OFFSET = sizeof(void*);
inline void EmitBaselineEnterStubFrame(MacroAssembler& masm, Register scratch) {
// Compute frame size. Because the return address is still on the stack,
// this is:
//
// BaselineFrameReg
// + BaselineFrame::FramePointerOffset
// - BaselineStackReg
// - sizeof(return address)
//
// The two constants cancel each other out, so we can just calculate
// BaselineFrameReg - BaselineStackReg.
static_assert(
BaselineFrame::FramePointerOffset == sizeof(void*),
"FramePointerOffset must be the same as the return address size");
masm.movl(BaselineFrameReg, scratch);
masm.subl(BaselineStackReg, scratch);
masm.store32(scratch, Address(BaselineFrameReg,
BaselineFrame::reverseOffsetOfFrameSize()));
// Note: when making changes here, don't forget to update STUB_FRAME_SIZE
// if needed.
// Push the return address that's currently on top of the stack.
masm.Push(Operand(BaselineStackReg, 0));
// Replace the original return address with the frame descriptor.
masm.makeFrameDescriptor(scratch, FrameType::BaselineJS,
BaselineStubFrameLayout::Size());
masm.storePtr(scratch, Address(BaselineStackReg, sizeof(uintptr_t)));
// Save old frame pointer, stack pointer and stub reg.
masm.Push(ICStubReg);
masm.Push(BaselineFrameReg);
masm.mov(BaselineStackReg, BaselineFrameReg);
}
} // namespace jit
} // namespace js
#endif /* jit_x86_SharedICHelpers_x86_inl_h */