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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_arm_SharedICHelpers_arm_h
#define jit_arm_SharedICHelpers_arm_h
#include "jit/BaselineFrame.h"
#include "jit/BaselineIC.h"
#include "jit/MacroAssembler.h"
#include "jit/SharedICRegisters.h"
namespace js {
namespace jit {
// Distance from sp to the top Value inside an IC stub (no return address on the
// stack on ARM).
static const size_t ICStackValueOffset = 0;
inline void EmitRestoreTailCallReg(MacroAssembler& masm) {
// No-op on ARM because link register is always holding the return address.
}
inline void EmitRepushTailCallReg(MacroAssembler& masm) {
// No-op on ARM because link register is always holding the return address.
}
inline void EmitCallIC(MacroAssembler& masm, const ICEntry* entry,
CodeOffset* callOffset) {
// Load stub pointer into ICStubReg.
masm.loadPtr(AbsoluteAddress(entry).offset(ICEntry::offsetOfFirstStub()),
ICStubReg);
// Load stubcode pointer from the ICStub.
// R2 won't be active when we call ICs, so we can use r0.
MOZ_ASSERT(R2 == ValueOperand(r1, r0));
masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0);
// Call the stubcode via a direct branch-and-link.
masm.ma_blx(r0);
*callOffset = CodeOffset(masm.currentOffset());
}
inline void EmitEnterTypeMonitorIC(
MacroAssembler& masm,
size_t monitorStubOffset = ICMonitoredStub::offsetOfFirstMonitorStub()) {
// This is expected to be called from within an IC, when ICStubReg is
// properly initialized to point to the stub.
masm.loadPtr(Address(ICStubReg, (uint32_t)monitorStubOffset), ICStubReg);
// Load stubcode pointer from BaselineStubEntry.
// R2 won't be active when we call ICs, so we can use r0.
MOZ_ASSERT(R2 == ValueOperand(r1, r0));
masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0);
// Jump to the stubcode.
masm.branch(r0);
}
inline void EmitReturnFromIC(MacroAssembler& masm) { masm.ma_mov(lr, pc); }
inline void EmitBaselineLeaveStubFrame(MacroAssembler& masm,
bool calledIntoIon = false) {
ScratchRegisterScope scratch(masm);
// Ion frames do not save and restore the frame pointer. If we called into
// Ion, we have to restore the stack pointer from the frame descriptor. If
// we performed a VM call, the descriptor has been popped already so in that
// case we use the frame pointer.
if (calledIntoIon) {
masm.Pop(scratch);
masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), scratch);
masm.add32(scratch, BaselineStackReg);
} else {
masm.mov(BaselineFrameReg, BaselineStackReg);
}
masm.Pop(BaselineFrameReg);
masm.Pop(ICStubReg);
// Load the return address.
masm.Pop(ICTailCallReg);
// Discard the frame descriptor.
masm.Pop(scratch);
}
template <typename AddrType>
inline void EmitPreBarrier(MacroAssembler& masm, const AddrType& addr,
MIRType type) {
// On ARM, lr is clobbered by guardedCallPreBarrier. Save it first.
masm.push(lr);
masm.guardedCallPreBarrier(addr, type);
masm.pop(lr);
}
inline void EmitStubGuardFailure(MacroAssembler& masm) {
// Load next stub into ICStubReg.
masm.loadPtr(Address(ICStubReg, ICStub::offsetOfNext()), ICStubReg);
// Return address is already loaded, just jump to the next stubcode.
MOZ_ASSERT(ICTailCallReg == lr);
masm.jump(Address(ICStubReg, ICStub::offsetOfStubCode()));
}
} // namespace jit
} // namespace js
#endif /* jit_arm_SharedICHelpers_arm_h */