platform_bionic/libc/platform/bionic/macros.h
Peter Collingbourne 2528dab741 Clean up untag_address.
We had two copies of this function, one (not quite correct) in tests/utils.h
and another in bionic/macros.h. Delete the former and have the users include
the latter.

Also, create an overload of the function that takes a uintptr_t, which will
be useful for out-of-process scenarios such as the MTE support in debuggerd.

Bug: 135772972
Change-Id: Ia3c2652c97797663146b3f05fa786afe09f7ea97
2020-03-20 15:35:54 -07:00

97 lines
3.3 KiB
C++

/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <stdint.h>
#define BIONIC_DISALLOW_COPY_AND_ASSIGN(TypeName) \
TypeName(const TypeName&) = delete; \
void operator=(const TypeName&) = delete
#define BIONIC_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
TypeName() = delete; \
BIONIC_DISALLOW_COPY_AND_ASSIGN(TypeName)
#define BIONIC_ROUND_UP_POWER_OF_2(value) \
((sizeof(value) == 8) \
? (1UL << (64 - __builtin_clzl(static_cast<unsigned long>(value)))) \
: (1UL << (32 - __builtin_clz(static_cast<unsigned int>(value)))))
static constexpr uintptr_t align_down(uintptr_t p, size_t align) {
return p & ~(align - 1);
}
static constexpr uintptr_t align_up(uintptr_t p, size_t align) {
return (p + align - 1) & ~(align - 1);
}
template <typename T>
static inline T* align_down(T* p, size_t align) {
return reinterpret_cast<T*>(align_down(reinterpret_cast<uintptr_t>(p), align));
}
template <typename T>
static inline T* align_up(T* p, size_t align) {
return reinterpret_cast<T*>(align_up(reinterpret_cast<uintptr_t>(p), align));
}
#if defined(__arm__)
#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined r14")
#elif defined(__aarch64__)
#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined x30")
#elif defined(__i386__)
#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined \%eip")
#elif defined(__x86_64__)
#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined \%rip")
#endif
// The arraysize(arr) macro returns the # of elements in an array arr.
// The expression is a compile-time constant, and therefore can be
// used in defining new arrays, for example. If you use arraysize on
// a pointer by mistake, you will get a compile-time error.
//
// One caveat is that arraysize() doesn't accept any array of an
// anonymous type or a type defined inside a function.
//
// This template function declaration is used in defining arraysize.
// Note that the function doesn't need an implementation, as we only
// use its type.
template <typename T, size_t N>
char (&ArraySizeHelper(T (&array)[N]))[N]; // NOLINT(readability/casting)
#define arraysize(array) (sizeof(ArraySizeHelper(array)))
// Used to inform clang's -Wimplicit-fallthrough that a fallthrough is intended. There's no way to
// silence (or enable, apparently) -Wimplicit-fallthrough in C yet.
#ifdef __cplusplus
#define __BIONIC_FALLTHROUGH [[clang::fallthrough]]
#else
#define __BIONIC_FALLTHROUGH
#endif
static inline uintptr_t untag_address(uintptr_t p) {
#if defined(__aarch64__)
return p & ((1ULL << 56) - 1);
#else
return p;
#endif
}
template <typename T>
static inline T* untag_address(T* p) {
return reinterpret_cast<T*>(untag_address(reinterpret_cast<uintptr_t>(p)));
}