| /* |
| * Copyright (C) 2013-2021 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| #include "CallFrame.h" |
| #include "JSCJSValue.h" |
| #include <wtf/MathExtras.h> |
| |
| namespace JSC { |
| |
| // NB. Different platforms may have different requirements here. But 16 bytes is very common. |
| constexpr unsigned stackAlignmentBytes() { return 16; } |
| |
| constexpr unsigned stackAlignmentRegisters() |
| { |
| return stackAlignmentBytes() / sizeof(EncodedJSValue); |
| } |
| |
| // Align argument count taking into account the CallFrameHeaderSize may be |
| // an "unaligned" count of registers. |
| inline unsigned roundArgumentCountToAlignFrame(unsigned argumentCount) |
| { |
| return WTF::roundUpToMultipleOf(stackAlignmentRegisters(), argumentCount + CallFrame::headerSizeInRegisters) - CallFrame::headerSizeInRegisters; |
| } |
| |
| // Align local register count to make the last local end on a stack aligned address given the |
| // CallFrame is at an address that is stack aligned minus CallerFrameAndPC::sizeInRegisters |
| inline unsigned roundLocalRegisterCountForFramePointerOffset(unsigned localRegisterCount) |
| { |
| return WTF::roundUpToMultipleOf(stackAlignmentRegisters(), localRegisterCount + CallerFrameAndPC::sizeInRegisters) - CallerFrameAndPC::sizeInRegisters; |
| } |
| |
| inline unsigned argumentCountForStackSize(unsigned sizeInBytes) |
| { |
| unsigned sizeInRegisters = sizeInBytes / sizeof(void*); |
| |
| if (sizeInRegisters <= CallFrame::headerSizeInRegisters) |
| return 0; |
| |
| return sizeInRegisters - CallFrame::headerSizeInRegisters; |
| } |
| |
| inline unsigned logStackAlignmentRegisters() |
| { |
| return WTF::fastLog2(stackAlignmentRegisters()); |
| } |
| |
| } // namespace JSC |
