1 files changed, 166 insertions, 0 deletions
diff --git a/src/Execution/Stack.php b/src/Execution/Stack.php
index 1fa2dae..439726d 100644
--- a/src/Execution/Stack.php
+++ b/src/Execution/Stack.php
@@ -4,6 +4,8 @@ declare(strict_types=1);
 
 namespace Nsfisis\Waddiwasi\Execution;
 
+use Nsfisis\Waddiwasi\Structure\Types\RefType;
+
 final class Stack
 {
     /**
@@ -19,11 +21,165 @@ final class Stack
         $this->entries[] = $entry;
     }
 
+    public function pushValue(Val $val): void
+    {
+        $this->push(StackEntry::Value($val));
+    }
+
+    public function pushBool(bool $value): void
+    {
+        $this->pushValue(Val::NumI32((int)$value));
+    }
+
+    /**
+     * @param S32 $value
+     */
+    public function pushI32(int $value): void
+    {
+        $this->pushValue(Val::NumI32($value));
+    }
+
+    /**
+     * @param S64 $value
+     */
+    public function pushI64(int $value): void
+    {
+        $this->pushValue(Val::NumI64($value));
+    }
+
+    /**
+     * @param F32 $value
+     */
+    public function pushF32(float $value): void
+    {
+        $this->pushValue(Val::NumF32($value));
+    }
+
+    /**
+     * @param F64 $value
+     */
+    public function pushF64(float $value): void
+    {
+        $this->pushValue(Val::NumF64($value));
+    }
+
+    public function pushRefNull(RefType $type): void
+    {
+        $this->pushValue(Val::RefNull($type));
+    }
+
+    public function pushRefFunc(FuncAddr $addr): void
+    {
+        $this->pushValue(Val::RefFunc($addr));
+    }
+
+    public function pushRefExtern(ExternAddr $addr): void
+    {
+        $this->pushValue(Val::RefExtern($addr));
+    }
+
     public function pop(): ?StackEntry
     {
         return array_pop($this->entries);
     }
 
+    public function popValue(): Val
+    {
+        $result = $this->pop();
+        assert($result instanceof StackEntries\Value);
+        return $result->inner;
+    }
+
+    /**
+     * @return list<Val>
+     */
+    public function popNValues(int $n): array
+    {
+        $results = [];
+        for ($i = 0; $i < $n; $i++) {
+            $results[] = $this->popValue();
+        }
+        return $results;
+    }
+
+    /**
+     * @return S32
+     */
+    public function popI32(): int
+    {
+        $v = $this->popValue();
+        assert($v instanceof Vals\Num);
+        assert($v->inner instanceof Nums\I32);
+        return $v->inner->value;
+    }
+
+    /**
+     * @return S64
+     */
+    public function popI64(): int
+    {
+        $v = $this->popValue();
+        assert($v instanceof Vals\Num);
+        assert($v->inner instanceof Nums\I64);
+        return $v->inner->value;
+    }
+
+    /**
+     * @return F32
+     */
+    public function popF32(): float
+    {
+        $v = $this->popValue();
+        assert($v instanceof Vals\Num);
+        assert($v->inner instanceof Nums\F32_);
+        return $v->inner->value;
+    }
+
+    /**
+     * @return F64
+     */
+    public function popF64(): float
+    {
+        $v = $this->popValue();
+        assert($v instanceof Vals\Num);
+        assert($v->inner instanceof Nums\F64_);
+        return $v->inner->value;
+    }
+
+    public function popRef(): Ref
+    {
+        $v = $this->popValue();
+        assert($v instanceof Vals\Ref);
+        return $v->inner;
+    }
+
+    /**
+     * @return list<Val>
+     */
+    public function popValuesToLabel(): array
+    {
+        $results = [];
+        while (!$this->isEmpty()) {
+            $top = $this->pop();
+            if ($top instanceof StackEntries\Value) {
+                $results[] = $top->inner;
+            } else {
+                assert($top instanceof StackEntries\Label);
+                break;
+            }
+        }
+        return $results;
+    }
+
+    public function popEntriesToCurrentFrame(): void
+    {
+        while (!$this->isEmpty()) {
+            if ($this->pop() instanceof StackEntries\Frame) {
+                return;
+            }
+        }
+    }
+
     public function top(): ?StackEntry
     {
         $n = array_key_last($this->entries);
@@ -39,4 +195,14 @@ final class Stack
     {
         return $this->count() === 0;
     }
+
+    public function currentFrame(): StackEntries\Frame
+    {
+        for ($i = count($this->entries) - 1; 0 <= $i; $i--) {
+            if ($this->entries[$i] instanceof StackEntries\Frame) {
+                return $this->entries[$i];
+            }
+        }
+        throw new \RuntimeException('No frame found');
+    }
 }