1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/jitcraft/Platform-Windows.cpp	Fri Jun 29 19:35:17 2012 -0700
     1.3 @@ -0,0 +1,115 @@
     1.4 +/*
     1.5 + * Copyright (C) 2012 David Anderson
     1.6 + *
     1.7 + * This file is part of JITCraft.
     1.8 + *
     1.9 + * JITCraft is free software: you can redistribute it and/or modify it under
    1.10 + * the terms of the GNU General Public License as published by the Free
    1.11 + * Software Foundation, either version 3 of the License, or (at your option)
    1.12 + * any later version.
    1.13 + * 
    1.14 + * Foobar is distributed in the hope that it will be useful, but WITHOUT ANY
    1.15 + * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    1.16 + * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
    1.17 + *
    1.18 + * You should have received a copy of the GNU General Public License along with
    1.19 + * JITCraft. If not, see http://www.gnu.org/licenses/.
    1.20 + */
    1.21 +
    1.22 +// :TODO: move into utility-style include
    1.23 +#define WIN32_LEAN_AND_MEAN
    1.24 +#include <Windows.h>
    1.25 +#include "Platform.h"
    1.26 +
    1.27 +using namespace jc;
    1.28 +
    1.29 +static inline DWORD
    1.30 +ToProtBits(OS::Protection prot)
    1.31 +{
    1.32 +    switch (prot) {
    1.33 +	  case OS::Prot_ReadWrite:
    1.34 +        return PAGE_READWRITE;
    1.35 +      case OS::Prot_ReadWriteExecute:
    1.36 +        return PAGE_EXECUTE_READWRITE;
    1.37 +      default:
    1.38 +        assert(prot == OS::Prot_ReadExecute);
    1.39 +        return PAGE_EXECUTE_READ;
    1.40 +    }
    1.41 +}
    1.42 +
    1.43 +Address
    1.44 +OS::MapMemory(size_t amount, MapMode mode, Protection prot_)
    1.45 +{
    1.46 +    DWORD prot = ToProtBits(prot_);
    1.47 +    DWORD type = MEM_RESERVE;
    1.48 +    if (mode == Map_Commit)
    1.49 +        type |= MEM_COMMIT;
    1.50 +
    1.51 +    return (Address)VirtualAlloc(NULL, amount, type, prot);
    1.52 +}
    1.53 +
    1.54 +bool
    1.55 +OS::CommitMemory(Address address, size_t amount, Protection prot_)
    1.56 +{
    1.57 +    DWORD prot = ToProtBits(prot_);
    1.58 +    return !!VirtualAlloc(address, amount, MEM_COMMIT, prot);
    1.59 +}
    1.60 +
    1.61 +void
    1.62 +OS::UnmapMemory(Address address, size_t size)
    1.63 +{
    1.64 +    VirtualFree(address, 0, MEM_RELEASE);
    1.65 +}
    1.66 +
    1.67 +OS::AlignableMapping
    1.68 +OS::MapAlignedMemory(size_t amount, size_t alignment, MapMode mode)
    1.69 +{
    1.70 +    Address addr = MapMemory(amount, mode, OS::Prot_ReadWrite);
    1.71 +    if (!addr)
    1.72 +        return AlignableMapping(NULL, alignment, 0);
    1.73 +
    1.74 +    if (!IsAligned(addr, alignment)) {
    1.75 +        UnmapMemory(addr, amount);
    1.76 +
    1.77 +        // Try to grab the next available aligned address.
    1.78 +        addr = AlignedBase(addr, alignment);
    1.79 +        addr = MapMemoryAt(addr + alignment, amount, mode, OS::Prot_ReadWrite);
    1.80 +        while (!addr) {
    1.81 +            // Try to over-allocate to get the right region. This can race
    1.82 +            // with other threads; we expect this to be rare. If this turns
    1.83 +            // out to be a problem, the API is set up such that we can just
    1.84 +            // return two pointers: the base, and the aligned address into
    1.85 +            // the over-allocated region.
    1.86 +            addr = MapMemory(amount + alignment, mode, OS::Prot_ReadWrite);
    1.87 +            if (!addr)
    1.88 +                return AlignableMapping(NULL, alignment, 0);
    1.89 +            UnmapMemory(addr, amount + alignment);
    1.90 +            addr = AlignedBase(addr, alignment);
    1.91 +            addr = MapMemoryAt(addr + alignment, amount, mode, OS::Prot_ReadWrite);
    1.92 +        }
    1.93 +    }
    1.94 +
    1.95 +    return AlignableMapping(addr, alignment, amount);
    1.96 +}
    1.97 +
    1.98 +Address
    1.99 +OS::MapMemoryAt(Address address, size_t amount, MapMode mode, Protection prot_)
   1.100 +{
   1.101 +    DWORD bits = ToProtBits(prot_);
   1.102 +    DWORD flags = MEM_RESERVE;
   1.103 +    if (mode == Map_Commit)
   1.104 +        flags |= MEM_COMMIT;
   1.105 +
   1.106 +    Address x = (Address)VirtualAlloc((LPVOID)address, amount, flags, bits);
   1.107 +    if (!x) {
   1.108 +        DWORD err = GetLastError();
   1.109 +        return x;
   1.110 +    }
   1.111 +    return x;
   1.112 +}
   1.113 +
   1.114 +void
   1.115 +OS::UnmapAlignedMemory(Address address, size_t size)
   1.116 +{
   1.117 +    OS::UnmapMemory(address, size);
   1.118 +}