1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/js/src/yarr/PageAllocation.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,131 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
1.5 + * vim: set ts=8 sts=4 et sw=4 tw=99:
1.6 + *
1.7 + * ***** BEGIN LICENSE BLOCK *****
1.8 + * Copyright (C) 2010 Apple Inc. All rights reserved.
1.9 + *
1.10 + * Redistribution and use in source and binary forms, with or without
1.11 + * modification, are permitted provided that the following conditions
1.12 + * are met:
1.13 + * 1. Redistributions of source code must retain the above copyright
1.14 + * notice, this list of conditions and the following disclaimer.
1.15 + * 2. Redistributions in binary form must reproduce the above copyright
1.16 + * notice, this list of conditions and the following disclaimer in the
1.17 + * documentation and/or other materials provided with the distribution.
1.18 + *
1.19 + * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
1.20 + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.21 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
1.22 + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
1.23 + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
1.24 + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
1.25 + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
1.26 + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
1.27 + * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.28 + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.29 + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.30 + *
1.31 + * ***** END LICENSE BLOCK ***** */
1.32 +
1.33 +#ifndef yarr_PageAllocation_h
1.34 +#define yarr_PageAllocation_h
1.35 +
1.36 +#include "yarr/wtfbridge.h"
1.37 +#include "yarr/OSAllocator.h"
1.38 +#include "yarr/PageBlock.h"
1.39 +#include "assembler/wtf/VMTags.h"
1.40 +
1.41 +#if WTF_OS_DARWIN
1.42 +#include <mach/mach_init.h>
1.43 +#include <mach/vm_map.h>
1.44 +#endif
1.45 +
1.46 +#if WTF_OS_HAIKU
1.47 +#include <OS.h>
1.48 +#endif
1.49 +
1.50 +#if WTF_OS_WINDOWS
1.51 +#include <malloc.h>
1.52 +#include <windows.h>
1.53 +#endif
1.54 +
1.55 +#if WTF_OS_SYMBIAN
1.56 +#include <e32hal.h>
1.57 +#include <e32std.h>
1.58 +#endif
1.59 +
1.60 +#if WTF_HAVE_ERRNO_H
1.61 +#include <errno.h>
1.62 +#endif
1.63 +
1.64 +#if WTF_HAVE_MMAP
1.65 +#include <sys/mman.h>
1.66 +#include <unistd.h>
1.67 +#endif
1.68 +
1.69 +namespace WTF {
1.70 +
1.71 +/*
1.72 + PageAllocation
1.73 +
1.74 + The PageAllocation class provides a cross-platform memory allocation interface
1.75 + with similar capabilities to posix mmap/munmap. Memory is allocated by calling
1.76 + PageAllocation::allocate, and deallocated by calling deallocate on the
1.77 + PageAllocation object. The PageAllocation holds the allocation's base pointer
1.78 + and size.
1.79 +
1.80 + The allocate method is passed the size required (which must be a multiple of
1.81 + the system page size, which can be accessed using PageAllocation::pageSize).
1.82 + Callers may also optinally provide a flag indicating the usage (for use by
1.83 + system memory usage tracking tools, where implemented), and boolean values
1.84 + specifying the required protection (defaulting to writable, non-executable).
1.85 +*/
1.86 +
1.87 +class PageAllocation : private PageBlock {
1.88 +public:
1.89 + PageAllocation()
1.90 + {
1.91 + }
1.92 +
1.93 + using PageBlock::size;
1.94 + using PageBlock::base;
1.95 +
1.96 +#ifndef __clang__
1.97 + using PageBlock::operator bool;
1.98 +#else
1.99 + // FIXME: This is a workaround for <rdar://problem/8876150>, wherein Clang incorrectly emits an access
1.100 + // control warning when a client tries to use operator bool exposed above via "using PageBlock::operator bool".
1.101 + operator bool() const { return PageBlock::operator bool(); }
1.102 +#endif
1.103 +
1.104 + static PageAllocation allocate(size_t size, OSAllocator::Usage usage = OSAllocator::UnknownUsage, bool writable = true, bool executable = false)
1.105 + {
1.106 + ASSERT(isPageAligned(size));
1.107 + return PageAllocation(OSAllocator::reserveAndCommit(size, usage, writable, executable), size);
1.108 + }
1.109 +
1.110 + void deallocate()
1.111 + {
1.112 + // Clear base & size before calling release; if this is *inside* allocation
1.113 + // then we won't be able to clear then after deallocating the memory.
1.114 + PageAllocation tmp;
1.115 + JSC::std::swap(tmp, *this);
1.116 +
1.117 + ASSERT(tmp);
1.118 + ASSERT(!*this);
1.119 +
1.120 + OSAllocator::decommitAndRelease(tmp.base(), tmp.size());
1.121 + }
1.122 +
1.123 +private:
1.124 + PageAllocation(void* base, size_t size)
1.125 + : PageBlock(base, size)
1.126 + {
1.127 + }
1.128 +};
1.129 +
1.130 +} // namespace WTF
1.131 +
1.132 +using WTF::PageAllocation;
1.133 +
1.134 +#endif /* yarr_PageAllocation_h */
