1//===- MemAlloc.h - Memory allocation functions -----------------*- C++ -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8/// \file 9/// 10/// This file defines counterparts of C library allocation functions defined in 11/// the namespace 'std'. The new allocation functions crash on allocation 12/// failure instead of returning null pointer. 13/// 14//===----------------------------------------------------------------------===// 15 16#ifndef LLVM_SUPPORT_MEMALLOC_H 17#define LLVM_SUPPORT_MEMALLOC_H 18 19#include "llvm/Support/Compiler.h" 20#include "llvm/Support/ErrorHandling.h" 21#include <cstdlib> 22 23namespace llvm { 24 25LLVM_ATTRIBUTE_RETURNS_NONNULL inline void *safe_malloc(size_t Sz) { 26 void *Result = std::malloc(Sz); 27 if (Result == nullptr) { 28 // It is implementation-defined whether allocation occurs if the space 29 // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting 30 // non-zero, if the space requested was zero. 31 if (Sz == 0) 32 return safe_malloc(1); 33 report_bad_alloc_error("Allocation failed"); 34 } 35 return Result; 36} 37 38LLVM_ATTRIBUTE_RETURNS_NONNULL inline void *safe_calloc(size_t Count, 39 size_t Sz) { 40 void *Result = std::calloc(Count, Sz); 41 if (Result == nullptr) { 42 // It is implementation-defined whether allocation occurs if the space 43 // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting 44 // non-zero, if the space requested was zero. 45 if (Count == 0 || Sz == 0) 46 return safe_malloc(1); 47 report_bad_alloc_error("Allocation failed"); 48 } 49 return Result; 50} 51 52LLVM_ATTRIBUTE_RETURNS_NONNULL inline void *safe_realloc(void *Ptr, size_t Sz) { 53 void *Result = std::realloc(Ptr, Sz); 54 if (Result == nullptr) { 55 // It is implementation-defined whether allocation occurs if the space 56 // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting 57 // non-zero, if the space requested was zero. 58 if (Sz == 0) 59 return safe_malloc(1); 60 report_bad_alloc_error("Allocation failed"); 61 } 62 return Result; 63} 64 65/// Allocate a buffer of memory with the given size and alignment. 66/// 67/// When the compiler supports aligned operator new, this will use it to 68/// handle even over-aligned allocations. 69/// 70/// However, this doesn't make any attempt to leverage the fancier techniques 71/// like posix_memalign due to portability. It is mostly intended to allow 72/// compatibility with platforms that, after aligned allocation was added, use 73/// reduced default alignment. 74LLVM_ATTRIBUTE_RETURNS_NONNULL LLVM_ATTRIBUTE_RETURNS_NOALIAS void * 75allocate_buffer(size_t Size, size_t Alignment); 76 77/// Deallocate a buffer of memory with the given size and alignment. 78/// 79/// If supported, this will used the sized delete operator. Also if supported, 80/// this will pass the alignment to the delete operator. 81/// 82/// The pointer must have been allocated with the corresponding new operator, 83/// most likely using the above helper. 84void deallocate_buffer(void *Ptr, size_t Size, size_t Alignment); 85 86} // namespace llvm 87#endif 88