1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/Platform-Windows.cpp	Tue Jul 24 23:53:34 2012 -0700
     1.3 @@ -0,0 +1,111 @@
     1.4 +/* vim: set ts=4 sw=4 tw=99 et:
     1.5 + *
     1.6 + * Copyright (C) 2012 David Anderson
     1.7 + *
     1.8 + * This file is part of JITCraft.
     1.9 + *
    1.10 + * JITCraft is free software: you can redistribute it and/or modify it under
    1.11 + * the terms of the GNU General Public License as published by the Free
    1.12 + * Software Foundation, either version 3 of the License, or (at your option)
    1.13 + * any later version.
    1.14 + * 
    1.15 + * Foobar is distributed in the hope that it will be useful, but WITHOUT ANY
    1.16 + * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    1.17 + * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
    1.18 + *
    1.19 + * You should have received a copy of the GNU General Public License along with
    1.20 + * JITCraft. If not, see http://www.gnu.org/licenses/.
    1.21 + */
    1.22 +
    1.23 +// :TODO: move into utility-style include
    1.24 +#define WIN32_LEAN_AND_MEAN
    1.25 +#include <Windows.h>
    1.26 +#include "Platform.h"
    1.27 +
    1.28 +using namespace ke;
    1.29 +
    1.30 +static inline DWORD
    1.31 +ToProtBits(OS::Protection prot)
    1.32 +{
    1.33 +    switch (prot) {
    1.34 +      case OS::Prot_ReadWrite:
    1.35 +        return PAGE_READWRITE;
    1.36 +      case OS::Prot_ReadWriteExecute:
    1.37 +        return PAGE_EXECUTE_READWRITE;
    1.38 +      default:
    1.39 +        assert(prot == OS::Prot_ReadExecute);
    1.40 +        return PAGE_EXECUTE_READ;
    1.41 +    }
    1.42 +}
    1.43 +
    1.44 +Address
    1.45 +OS::MapMemory(size_t amount, MapMode mode, Protection prot_)
    1.46 +{
    1.47 +    DWORD prot = ToProtBits(prot_);
    1.48 +    DWORD type = MEM_RESERVE;
    1.49 +    if (mode == Map_Commit)
    1.50 +        type |= MEM_COMMIT;
    1.51 +
    1.52 +    return (Address)VirtualAlloc(NULL, amount, type, prot);
    1.53 +}
    1.54 +
    1.55 +bool
    1.56 +OS::CommitMemory(Address address, size_t amount, Protection prot_)
    1.57 +{
    1.58 +    DWORD prot = ToProtBits(prot_);
    1.59 +    return !!VirtualAlloc(address, amount, MEM_COMMIT, prot);
    1.60 +}
    1.61 +
    1.62 +void
    1.63 +OS::UnmapMemory(Address address, size_t size)
    1.64 +{
    1.65 +    VirtualFree(address, 0, MEM_RELEASE);
    1.66 +}
    1.67 +
    1.68 +static Address
    1.69 +MapMemoryAt(Address address, size_t amount, OS::MapMode mode, OS::Protection prot_)
    1.70 +{
    1.71 +    DWORD bits = ToProtBits(prot_);
    1.72 +    DWORD flags = MEM_RESERVE;
    1.73 +    if (mode == OS::Map_Commit)
    1.74 +        flags |= MEM_COMMIT;
    1.75 +
    1.76 +    return (Address)VirtualAlloc((LPVOID)address, amount, flags, bits);
    1.77 +}
    1.78 +
    1.79 +OS::AlignableMapping
    1.80 +OS::MapAlignedMemory(size_t amount, size_t alignment, MapMode mode)
    1.81 +{
    1.82 +    Address addr = MapMemory(amount, mode, OS::Prot_ReadWrite);
    1.83 +    if (!addr)
    1.84 +        return AlignableMapping(NULL, alignment, 0);
    1.85 +
    1.86 +    if (!IsAligned(addr, alignment)) {
    1.87 +        UnmapMemory(addr, amount);
    1.88 +
    1.89 +        // Try to grab the next available aligned address.
    1.90 +        addr = AlignedBase(addr, alignment);
    1.91 +        addr = MapMemoryAt(addr + alignment, amount, mode, OS::Prot_ReadWrite);
    1.92 +        while (!addr) {
    1.93 +            // Try to over-allocate to get the right region. This can race
    1.94 +            // with other threads; we expect this to be rare. If this turns
    1.95 +            // out to be a problem, the API is set up such that we can just
    1.96 +            // return two pointers: the base, and the aligned address into
    1.97 +            // the over-allocated region.
    1.98 +            addr = MapMemory(amount + alignment, mode, OS::Prot_ReadWrite);
    1.99 +            if (!addr)
   1.100 +                return AlignableMapping(NULL, alignment, 0);
   1.101 +            UnmapMemory(addr, amount + alignment);
   1.102 +            addr = AlignedBase(addr, alignment);
   1.103 +            addr = MapMemoryAt(addr + alignment, amount, mode, OS::Prot_ReadWrite);
   1.104 +        }
   1.105 +    }
   1.106 +
   1.107 +    return AlignableMapping(addr, alignment, amount);
   1.108 +}
   1.109 +
   1.110 +void
   1.111 +OS::UnmapAlignedMemory(Address address, size_t size)
   1.112 +{
   1.113 +    OS::UnmapMemory(address, size);
   1.114 +}