1 files changed, 162 insertions, 0 deletions
diff --git a/src/Execution/Allocator.php b/src/Execution/Allocator.php
new file mode 100644
index 0000000..ad62fc7
--- /dev/null
+++ b/src/Execution/Allocator.php
@@ -0,0 +1,162 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Nsfisis\Waddiwasi\Execution;
+
+use Nsfisis\Waddiwasi\Structure\Modules\ExportDescs;
+use Nsfisis\Waddiwasi\Structure\Modules\Func;
+use Nsfisis\Waddiwasi\Structure\Modules\Module;
+use Nsfisis\Waddiwasi\Structure\Types\GlobalType;
+use Nsfisis\Waddiwasi\Structure\Types\MemType;
+use Nsfisis\Waddiwasi\Structure\Types\RefType;
+use Nsfisis\Waddiwasi\Structure\Types\TableType;
+
+final readonly class Allocator
+{
+    public function __construct(
+        private readonly Store $store,
+    ) {
+    }
+
+    /**
+     * @param list<ExternVal> $externVals
+     */
+    public function allocPreInitModule(
+        Module $module,
+        array $externVals,
+    ): ModuleInst {
+        $m = new ModuleInst($module->types, [], [], [], [], [], [], []);
+
+        foreach ($externVals as $externVal) {
+            if ($externVal instanceof ExternVals\Global_) {
+                $m->globalAddrs[] = $externVal->addr;
+            }
+        }
+        foreach ($module->funcs as $func) {
+            $m->funcAddrs[] = $this->allocFunc($func, $m);
+        }
+
+        return $m;
+    }
+
+    /**
+     * @param list<ExternVal> $externVals
+     * @param list<Val> $vals
+     * @param list<list<Ref>> $refsList
+     * @param list<FuncAddr> $preAllocatedFuncs
+     */
+    public function allocModule(
+        Module $module,
+        array $externVals,
+        array $vals,
+        array $refsList,
+        array $preAllocatedFuncs,
+    ): ModuleInst {
+        $m = new ModuleInst($module->types, [], [], [], [], [], [], []);
+
+        foreach ($externVals as $externVal) {
+            match ($externVal::class) {
+                ExternVals\Func::class => $m->funcAddrs[] = $externVal->addr,
+                ExternVals\Table::class => $m->tableAddrs[] = $externVal->addr,
+                ExternVals\Mem::class => $m->memAddrs[] = $externVal->addr,
+                ExternVals\Global_::class => $m->globalAddrs[] = $externVal->addr,
+                default => throw new \RuntimeException("unreachable"),
+            };
+        }
+
+        foreach ($preAllocatedFuncs as $funcAddr) {
+            $m->funcAddrs[] = $funcAddr;
+            $funcInst = $this->store->funcs[$funcAddr->value];
+            assert($funcInst instanceof FuncInsts\Wasm);
+            // @phpstan-ignore-next-line
+            $this->store->funcs[$funcAddr->value] = FuncInst::Wasm(
+                $funcInst->type,
+                $m,
+                $funcInst->code,
+            );
+        }
+        foreach ($module->tables as $table) {
+            $m->tableAddrs[] = $this->allocTable($table->type, Ref::RefNull($table->type->refType));
+        }
+        foreach ($module->mems as $mem) {
+            $m->memAddrs[] = $this->allocMem($mem->type);
+        }
+        foreach ($module->datas as $data) {
+            $m->dataAddrs[] = $this->allocData($data->init);
+        }
+
+        foreach ($module->globals as $i => $global) {
+            $m->globalAddrs[] = $this->allocGlobal($global->type, $vals[$i]);
+        }
+        foreach ($module->elems as $i => $elem) {
+            $m->elemAddrs[] = $this->allocElem($elem->type, $refsList[$i]);
+        }
+
+        foreach ($module->exports as $export) {
+            $value = match ($export->desc::class) {
+                ExportDescs\Func::class => ExternVal::Func($m->funcAddrs[$export->desc->func->value]),
+                ExportDescs\Table::class => ExternVal::Table($m->tableAddrs[$export->desc->table->value]),
+                ExportDescs\Mem::class => ExternVal::Mem($m->memAddrs[$export->desc->mem->value]),
+                ExportDescs\Global_::class => ExternVal::Global_($m->globalAddrs[$export->desc->global->value]),
+                default => throw new \RuntimeException("unreachable"),
+            };
+            $m->exports[] = new ExportInst($export->name, $value);
+        }
+
+        return $m;
+    }
+
+    private function allocFunc(Func $func, ModuleInst $moduleInst): FuncAddr
+    {
+        $funcType = $moduleInst->types[$func->type->value];
+        $funcInst = FuncInst::Wasm($funcType, $moduleInst, $func);
+        $this->store->funcs[] = $funcInst;
+        return new FuncAddr(count($this->store->funcs) - 1);
+    }
+
+    private function allocTable(TableType $tableType, Ref $ref): TableAddr
+    {
+        $minSize = $tableType->limits->min;
+        $elem = array_fill(0, $minSize, $ref);
+        $tableInst = new TableInst($tableType, $elem);
+        $this->store->tables[] = $tableInst;
+        return new TableAddr(count($this->store->tables) - 1);
+    }
+
+    private function allocMem(MemType $memType): MemAddr
+    {
+        $minSize = $memType->limits->min;
+        $data = array_fill(0, $minSize * 64 * 1024, 0);
+        $memInst = new MemInst($memType, $data);
+        $this->store->mems[] = $memInst;
+        return new MemAddr(count($this->store->mems) - 1);
+    }
+
+    private function allocGlobal(GlobalType $globalType, Val $val): GlobalAddr
+    {
+        $globalInst = new GlobalInst($globalType, $val);
+        $this->store->globals[] = $globalInst;
+        return new GlobalAddr(count($this->store->globals) - 1);
+    }
+
+    /**
+     * @param list<Ref> $elem
+     */
+    private function allocElem(RefType $refType, array $elem): ElemAddr
+    {
+        $elemInst = new ElemInst($refType, $elem);
+        $this->store->elems[] = $elemInst;
+        return new ElemAddr(count($this->store->elems) - 1);
+    }
+
+    /**
+     * @param list<Byte> $data
+     */
+    private function allocData(array $data): DataAddr
+    {
+        $dataInst = new DataInst($data);
+        $this->store->datas[] = $dataInst;
+        return new DataAddr(count($this->store->datas) - 1);
+    }
+}