diff --git a/examples/simple.php b/examples/simple.php
index 9a4b0d8f..6e1eee41 100644
--- a/examples/simple.php
+++ b/examples/simple.php
@@ -1,10 +1,13 @@
 <?php
-function main() {
-    $a = 0;
-    for ($i = 0; $i < 1000000; $i++)
-        $a++;
+function Ack($m, $n){
+    if($m == 0) return $n+1;
+    if($n == 0) return Ack($m-1, 1);
+    return Ack($m - 1, Ack($m, ($n - 1)));
+}
+
 
-    $thisisanotherlongname = 0;
-    for ($thisisalongname = 0; $thisisalongname < 1000000; $thisisalongname++)
-        $thisisanotherlongname++;
+function main() {
+    $n = 7;
+    $r = Ack(3, $n);
+    print "Ack(3,$n): $r\n";
 }
\ No newline at end of file
diff --git a/main.cc b/main.cc
index 121832cc..ed765e3e 100644
--- a/main.cc
+++ b/main.cc
@@ -29,6 +29,7 @@ int main(int cpp_argc, char **cpp_argv) {
 #endif
     argc.unset();
     argv.unset();
+    php::request_shutdown();
     php_embed_shutdown();
     return rc;
 }
diff --git a/src/Php/Translator.php b/src/Php/Translator.php
index c91b28eb..1e88128e 100644
--- a/src/Php/Translator.php
+++ b/src/Php/Translator.php
@@ -31,6 +31,8 @@ class Translator extends \PhpAot\Core\Translator
     protected string $lang = 'PHP';
     private string $cppCompiler = 'g++';
     private array $arguments = [];
+    private array $literalStrings = [];
+    private int $literalStringIndex = 0;
     private int $tmpVarIndex = 0;
     private array $zendTypeMap = [
         'int' => self::TYPE_INT,
@@ -40,6 +42,7 @@ class Translator extends \PhpAot\Core\Translator
 
     private array $headers = [
         'phpx.h',
+        'phpx_helper.h',
         'phpx_func.h',
         'php_func_decl.h',
     ];
@@ -229,6 +232,9 @@ class Translator extends \PhpAot\Core\Translator
         foreach ($this->globalVars as $name => $type) {
             $lines[] = 'extern ' . self::TYPE_VAR . ' ' . $name . ';';
         }
+
+        $literalStringsCount = count($this->literalStrings);
+        $lines[] = 'extern php::Var _literal_strings[' . $literalStringsCount . '];' . PHP_EOL;
         return implode(PHP_EOL, $lines) . PHP_EOL . PHP_EOL;
     }
 
@@ -286,6 +292,7 @@ class Translator extends \PhpAot\Core\Translator
                 return $this->doConvert($phpCode);
             } catch (ReturnTypeChanged $e) {
                 // 某些情况，例如返回值变更，需要重新解析
+                $this->climate->cyan('Return type changed, retrying...');
                 continue;
             }
         }
@@ -362,6 +369,13 @@ class Translator extends \PhpAot\Core\Translator
             $this->internalFunctions[$name] = $this->functionDef;
         }
 
+        foreach ($this->functionDef->argInfoList as $argInfo) {
+            $this->arguments[$argInfo->name] = $argInfo->type;
+            if (!$this->hasLocalVar($argInfo->name)) {
+                $this->addLocalVar($argInfo->name, $argInfo->type);
+            }
+        }
+
         $this->indentLevel++;
         $stmts = $this->parseStmts($v->stmts);
         $this->indentLevel--;
@@ -410,7 +424,8 @@ class Translator extends \PhpAot\Core\Translator
             case 'Scalar_Float':
                 return $this->parseScalarFloat($expr);
             case 'Scalar_String':
-                return '"' . $this->escapeString($expr->value) . '"';
+                $index = $this->literalStrings[$expr->value] ?? $this->addLiteralString($expr->value);
+                return '_literal_strings[' . $index . ']';
             case 'Expr_ConstFetch':
                 return $this->parseConstFetch($expr);
             default:
@@ -426,9 +441,6 @@ class Translator extends \PhpAot\Core\Translator
             $type = $this->parseType($param->type);
             $name = $this->parseIdentifier($param->var);
             $list[] = $type . ' ' . $name;
-            $this->arguments[$name] = $type;
-            $this->addLocalVar($name, $type);
-
             $argInfo = new ArgInfo();
             $argInfo->name = $name;
             $argInfo->type = $type;
@@ -806,6 +818,13 @@ class Translator extends \PhpAot\Core\Translator
         $this->localVars[$name] = $type;
     }
 
+    private function addLiteralString(string $value): int
+    {
+        $index = $this->literalStringIndex++;
+        $this->literalStrings[$value] = $index;
+        return $index;
+    }
+
     private function addGlobalVar(string $name, string $type): void
     {
         $this->globalVars[$name] = $type;
@@ -1162,8 +1181,8 @@ class Translator extends \PhpAot\Core\Translator
         } else {
             $fn = '"' . $name . '"';
         }
-        if ($name === 'strlen' and $expr->args[0]->value->getType() === 'Expr_Variable') {
-            return '((php::Int)' . $this->parseIdentifier($expr->args[0]->value) . '.length())';
+        if ($name === 'strlen') {
+            return 'php::len(' . $this->parseIdentifier($expr->args[0]->value) . ')';
         }
         if (count($expr->args) == 1) {
             switch ($name) {
@@ -1894,6 +1913,17 @@ class Translator extends \PhpAot\Core\Translator
             $lines[] = self::TYPE_VAR . ' ' . $name . ';';
         }
         $code .= implode(PHP_EOL, $lines) . PHP_EOL;
+
+        $code .= PHP_EOL;
+        $literalStringsCount = count($this->literalStrings);
+        $code .= 'php::Var _literal_strings[' . $literalStringsCount . '] = {' . PHP_EOL;
+        $this->indentLevel++;
+        foreach ($this->literalStrings as $str => $index) {
+            $code .= $this->getIndent() . 'php::String{ZEND_STRL("' . $this->escapeString($str) . '"), true},' . PHP_EOL;
+        }
+        $this->indentLevel--;
+        $code .= '};' . PHP_EOL;
+
         file_put_contents($file, $code);
     }
 
diff --git a/tests/aot/fib.phpt b/tests/aot/fib.phpt
new file mode 100644
index 00000000..29dce2ac
--- /dev/null
+++ b/tests/aot/fib.phpt
@@ -0,0 +1,30 @@
+--TEST--
+Fibonacci
+--FILE--
+<?php
+function fib(int $n): int
+{
+    if ($n == 1 || $n == 2) {
+        return 1;
+    } else {
+        return fib($n - 1) + fib($n - 2);
+    }
+}
+
+function main()
+{
+    $n = 40;
+    if ($n > 100) {
+        echo "Too big number\n";
+        exit(1);
+    } elseif ($n < 1) {
+        echo "Too small number\n";
+        exit(1);
+    }
+
+    $begin = microtime(true);
+    echo fib($n) . "\n";
+}
+?>
+--EXPECT--
+102334155
\ No newline at end of file
diff --git a/tests/aot/pi.phpt b/tests/aot/pi.phpt
new file mode 100644
index 00000000..7b70bebc
--- /dev/null
+++ b/tests/aot/pi.phpt
@@ -0,0 +1,25 @@
+--TEST--
+π
+--FILE--
+<?php
+function main()
+{
+    ini_set("precision", 17);
+    $rounds = 1_0000_0000;
+    $stop = $rounds + 2;
+
+    $begin = microtime(true);
+    $x = 1.0;
+    $pi = 1.0;
+
+    for ($i = 2; $i <= $stop; $i++) {
+        $x = -1.0 + 2.0 * ($i & 0x1);
+        $pi += $x / (2 * $i - 1);
+    }
+
+    $pi *= 4.0;
+    print $pi . "\n";
+}
+?>
+--EXPECT--
+3.141592643589326
\ No newline at end of file