1/*
2 * Copyright (C) 2018 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28namespace WTF {
29
30#if defined(NDEBUG) && COMPILER(GCC_COMPATIBLE) \
31 && (CPU(X86_64) || CPU(X86) || CPU(ARM64) || CPU(ARM_THUMB2) || CPU(ARM_TRADITIONAL))
32
33// We can only use the inline asm implementation on release builds because it
34// needs to be inlinable in order to be correct.
35ALWAYS_INLINE void* currentStackPointer()
36{
37 void* stackPointer = nullptr;
38#if CPU(X86_64)
39 __asm__ volatile ("movq %%rsp, %0" : "=r"(stackPointer) ::);
40#elif CPU(X86)
41 __asm__ volatile ("movl %%esp, %0" : "=r"(stackPointer) ::);
42#elif CPU(ARM64) && defined(__ILP32__)
43 uint64_t stackPointerRegister = 0;
44 __asm__ volatile ("mov %0, sp" : "=r"(stackPointerRegister) ::);
45 stackPointer = reinterpret_cast<void*>(stackPointerRegister);
46#elif CPU(ARM64) || CPU(ARM_THUMB2) || CPU(ARM_TRADITIONAL)
47 __asm__ volatile ("mov %0, sp" : "=r"(stackPointer) ::);
48#endif
49 return stackPointer;
50}
51
52#else
53
54#define USE_GENERIC_CURRENT_STACK_POINTER 1
55WTF_EXPORT_PRIVATE void* currentStackPointer();
56
57#endif
58
59} // namespace WTF
60
61using WTF::currentStackPointer;
62