1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/jitcraft/Environments.cpp	Mon Jul 23 01:19:44 2012 -0700
     1.3 @@ -0,0 +1,97 @@
     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 +#include "Utility.h"
    1.22 +#include "Environments.h"
    1.23 +#include "Structures.h"
    1.24 +#include "FixedArray.h"
    1.25 +#include "Zone.h"
    1.26 +#include "NameBinding.h"
    1.27 +
    1.28 +using namespace ke;
    1.29 +
    1.30 +EnvironmentSlotDescriptorArray *
    1.31 +EnvironmentSlotDescriptorArray::New(Zone *zone, unsigned nslots)
    1.32 +{
    1.33 +    size_t bytesNeeded = sizeof(EnvironmentSlotDescriptorArray) +
    1.34 +                         sizeof(EnvironmentSlotDescriptor) * nslots;
    1.35 +
    1.36 +    Local<EnvironmentSlotDescriptorArray> array(zone);
    1.37 +    Local<Map> map(zone, zone->getMap(MapKind_EnvironmentSlotDescriptorArray));
    1.38 +
    1.39 +    array = EnvironmentSlotDescriptorArray::cast(zone->allocate(map, bytesNeeded, Heap::Tenure_Old));
    1.40 +    if (!array)
    1.41 +        return NULL;
    1.42 +
    1.43 +    // We zero the array for safety, since we could GC or fail before initialization.
    1.44 +    array->length_ = nslots;
    1.45 +    memset(array->slots(), 0, sizeof(EnvironmentSlotDescriptor) * nslots);
    1.46 +    return array;
    1.47 +}
    1.48 +
    1.49 +Environment *
    1.50 +Environment::New(Zone *zone, Handle<EnvironmentMap> map, Heap::Tenure tenure)
    1.51 +{
    1.52 +    size_t bytesNeeded = sizeof(Environment) + map->structureSize();
    1.53 +    Local<Environment> env(zone, Environment::cast(zone->allocate(map, bytesNeeded, tenure)));
    1.54 +    if (!env)
    1.55 +        return NULL;
    1.56 +
    1.57 +    // Initialize when called from C++, to make sure object slots are NULL.
    1.58 +    memset((Object *)env + 1, 0, map->structureSize());
    1.59 +    return env;
    1.60 +}
    1.61 +
    1.62 +EnvironmentMap *
    1.63 +EnvironmentMap::New(Zone *zone, unsigned nvars, Variable **vars)
    1.64 +{
    1.65 +    StructureBufferBuilder structure;
    1.66 +
    1.67 +    Local<EnvironmentSlotDescriptorArray> slots(zone);
    1.68 +    slots = EnvironmentSlotDescriptorArray::New(zone, nvars);
    1.69 +    if (!slots)
    1.70 +        return NULL;
    1.71 +
    1.72 +    // Build the descriptor table, mapping each slot to an offset and type.
    1.73 +    Local<Type> type(zone);
    1.74 +    for (unsigned i = 0; i < nvars; i++) {
    1.75 +        assert(vars[i]->slot() == i);
    1.76 +        type = vars[i]->type();
    1.77 +
    1.78 +        EnvironmentSlotDescriptor &desc = slots->slots()[i];
    1.79 +        if (!structure.add(type, &desc.offset))
    1.80 +            return NULL;
    1.81 +
    1.82 +        desc.type = type;
    1.83 +    }
    1.84 +
    1.85 +    // Allocate the actual map now.
    1.86 +    size_t bytesNeeded = sizeof(EnvironmentMap) + structure.traceableOffsetCount() * sizeof(unsigned);
    1.87 +    Local<EnvironmentMap> map(zone);
    1.88 +    
    1.89 +    map = EnvironmentMap::cast(zone->allocateMap(MapKind_Environment, bytesNeeded, MapKind_MetaEnvironment));
    1.90 +    if (!map)
    1.91 +        return NULL;
    1.92 +    
    1.93 +    // Fill in the map fields, and copy the traceable offsets structure.
    1.94 +    map->structureSize_ = structure.structureSize();
    1.95 +    map->traceOffsetCount_ = structure.traceableOffsetCount();
    1.96 +    map->slots_ = slots;
    1.97 +    memcpy(const_cast<unsigned *>(map->traceOffsets()), structure.offsets(), sizeof(unsigned) * structure.traceableOffsetCount());
    1.98 +
    1.99 +    return map;
   1.100 +}