diff --git a/examples/n-body/assembly/index.ts b/examples/n-body/assembly/index.ts
index 6f3ea912..9a37c2d6 100644
--- a/examples/n-body/assembly/index.ts
+++ b/examples/n-body/assembly/index.ts
@@ -96,7 +96,7 @@ class NBodySystem {
       py += b.vy * m;
       pz += b.vz * m;
     }
-    bodies[0].offsetMomentum(px, py, pz);
+    unchecked(bodies[0]).offsetMomentum(px, py, pz);
   }
 
   advance(dt: float): void {
@@ -206,5 +206,5 @@ export function bench(steps: u32): void {
 
 export function getBody(index: i32): Body | null {
   var bodies = system.bodies;
-  return <u32>index < <u32>bodies.length ? bodies[index] : null;
+  return <u32>index < <u32>bodies.length ? unchecked(bodies[index]) : null;
 }
diff --git a/examples/n-body/build/index.asm.js b/examples/n-body/build/index.asm.js
index 8dd198d0..f9dbb20d 100644
--- a/examples/n-body/build/index.asm.js
+++ b/examples/n-body/build/index.asm.js
@@ -20,32 +20,45 @@ function asmFunc(global, env, buffer) {
  var abort = env.abort;
  var nan = global.NaN;
  var infinity = global.Infinity;
+ var assembly_index_system = 0;
  var $lib_allocator_arena_startOffset = 0;
  var $lib_allocator_arena_offset = 0;
- var assembly_index_system = 0;
  var i64toi32_i32$HIGH_BITS = 0;
- function $lib_allocator_arena___memory_allocate($0) {
+ function $lib_memory_memory_allocate($0) {
   $0 = $0 | 0;
   var $1 = 0, $2 = 0, $3 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0, wasm2js_i32$2 = 0;
   if ($0 >>> 0 > 1073741824 >>> 0) abort();
   $1 = $lib_allocator_arena_offset;
-  $2 = (($1 + (wasm2js_i32$0 = $0, wasm2js_i32$1 = 1, wasm2js_i32$2 = $0 >>> 0 > 1 >>> 0, wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) + 7 | 0) & 4294967288 | 0;
-  $3 = __wasm_current_memory();
-  if ($2 >>> 0 > ($3 << 16 | 0) >>> 0) {
-   $0 = ((($2 - $1 | 0) + 65535 | 0) & 4294901760 | 0) >>> 16 | 0;
-   if ((__wasm_grow_memory((wasm2js_i32$0 = $3, wasm2js_i32$1 = $0, wasm2js_i32$2 = ($3 | 0) > ($0 | 0), wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) | 0) < (0 | 0)) if ((__wasm_grow_memory($0 | 0) | 0) < (0 | 0)) abort();;
+  $0 = (($1 + (wasm2js_i32$0 = $0, wasm2js_i32$1 = 1, wasm2js_i32$2 = $0 >>> 0 > 1 >>> 0, wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) + 7 | 0) & 4294967288 | 0;
+  $2 = __wasm_current_memory();
+  if ($0 >>> 0 > ($2 << 16 | 0) >>> 0) {
+   $3 = ((($0 - $1 | 0) + 65535 | 0) & 4294901760 | 0) >>> 16 | 0;
+   if ((__wasm_grow_memory((wasm2js_i32$0 = $2, wasm2js_i32$1 = $3, wasm2js_i32$2 = ($2 | 0) > ($3 | 0), wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) | 0) < (0 | 0)) if ((__wasm_grow_memory($3 | 0) | 0) < (0 | 0)) abort();;
   }
-  $lib_allocator_arena_offset = $2;
+  $lib_allocator_arena_offset = $0;
   return $1 | 0;
  }
  
+ function $lib_runtime_doAllocate($0) {
+  $0 = $0 | 0;
+  var $1 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
+  $1 = $lib_memory_memory_allocate(1 << (32 - Math_clz32($0 + 7 | 0) | 0) | 0 | 0) | 0;
+  wasm2js_i32$0 = $1;
+  wasm2js_i32$1 = 2774420247;
+  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $1;
+  wasm2js_i32$1 = $0;
+  HEAP32[(wasm2js_i32$0 + 4 | 0) >> 2] = wasm2js_i32$1;
+  return $1 + 8 | 0 | 0;
+ }
+ 
  function assembly_index_NBodySystem_constructor($0) {
   $0 = $0 | 0;
-  var $1 = 0, $2 = 0, $3 = 0.0, $4 = 0.0, $5 = 0.0, $6 = 0.0, $7 = 0, $49 = 0, wasm2js_i32$0 = 0, wasm2js_f64$0 = 0.0, wasm2js_i32$1 = 0;
-  $7 = HEAP32[($0 + 4 | 0) >> 2] | 0;
+  var $1 = 0, $2 = 0, $3 = 0.0, $4 = 0.0, $5 = 0.0, $6 = 0.0, $7 = 0, wasm2js_i32$0 = 0, wasm2js_f64$0 = 0.0, wasm2js_i32$1 = 0;
+  $7 = HEAP32[($0 + 12 | 0) >> 2] | 0;
   repeat_0 : do {
    if (($1 | 0) < ($7 | 0)) {
-    $2 = HEAPU32[(((HEAPU32[$0 >> 2] | 0) + ($1 << 2 | 0) | 0) + 8 | 0) >> 2] | 0;
+    $2 = HEAPU32[((HEAP32[($0 + 4 | 0) >> 2] | 0) + ($1 << 2 | 0) | 0) >> 2] | 0;
     $3 = +HEAPF64[($2 + 48 | 0) >> 3];
     $4 = $4 + +HEAPF64[($2 + 24 | 0) >> 3] * $3;
     $5 = $5 + +HEAPF64[($2 + 32 | 0) >> 3] * $3;
@@ -55,9 +68,7 @@ function asmFunc(global, env, buffer) {
    }
    break repeat_0;
   } while (1);
-  $1 = HEAPU32[$0 >> 2] | 0;
-  if (0 >>> 0 < ((HEAP32[$1 >> 2] | 0) >>> 2 | 0) >>> 0) $49 = HEAPU32[($1 + 8 | 0) >> 2] | 0; else abort();
-  $1 = $49;
+  $1 = HEAPU32[(HEAP32[($0 + 4 | 0) >> 2] | 0) >> 2] | 0;
   wasm2js_i32$0 = $1;
   wasm2js_f64$0 = -$4 / 39.47841760435743;
   HEAPF64[(wasm2js_i32$0 + 24 | 0) >> 3] = wasm2js_f64$0;
@@ -67,7 +78,10 @@ function asmFunc(global, env, buffer) {
   wasm2js_i32$0 = $1;
   wasm2js_f64$0 = -$6 / 39.47841760435743;
   HEAPF64[(wasm2js_i32$0 + 40 | 0) >> 3] = wasm2js_f64$0;
-  $1 = $lib_allocator_arena___memory_allocate(4 | 0) | 0;
+  $1 = $lib_runtime_doAllocate(4 | 0) | 0;
+  wasm2js_i32$0 = $1 - 8 | 0;
+  wasm2js_i32$1 = 1;
+  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
   wasm2js_i32$0 = $1;
   wasm2js_i32$1 = $0;
   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
@@ -82,8 +96,11 @@ function asmFunc(global, env, buffer) {
   $4 = +$4;
   $5 = +$5;
   $6 = +$6;
-  var $7 = 0, wasm2js_i32$0 = 0, wasm2js_f64$0 = 0.0;
-  $7 = $lib_allocator_arena___memory_allocate(56 | 0) | 0;
+  var $7 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0, wasm2js_f64$0 = 0.0;
+  $7 = $lib_runtime_doAllocate(56 | 0) | 0;
+  wasm2js_i32$0 = $7 - 8 | 0;
+  wasm2js_i32$1 = 2;
+  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
   wasm2js_i32$0 = $7;
   wasm2js_f64$0 = $0;
   HEAPF64[wasm2js_i32$0 >> 3] = wasm2js_f64$0;
@@ -108,135 +125,145 @@ function asmFunc(global, env, buffer) {
   return $7 | 0;
  }
  
- function $lib_internal_memory_memset($0) {
+ function $lib_memory_memory_fill($0) {
   $0 = $0 | 0;
   var $1 = 0, $2 = 0, i64toi32_i32$1 = 0, i64toi32_i32$0 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0, wasm2js_i32$2 = 0, wasm2js_i32$3 = 0;
-  wasm2js_i32$0 = $0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  $1 = $0 + 20 | 0;
-  wasm2js_i32$0 = $1 - 1 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 1 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 2 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 2 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 3 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 3 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 4 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
-  $1 = (0 - $0 | 0) & 3 | 0;
-  $0 = $1 + $0 | 0;
-  wasm2js_i32$0 = $0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  $2 = (20 - $1 | 0) & 4294967292 | 0;
-  wasm2js_i32$0 = ($2 + $0 | 0) - 4 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  if ($2 >>> 0 <= 8 >>> 0) return;
-  wasm2js_i32$0 = $0 + 4 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 8 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  $1 = $0 + $2 | 0;
-  wasm2js_i32$0 = $1 - 12 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 8 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  if ($2 >>> 0 <= 24 >>> 0) return;
-  wasm2js_i32$0 = $0 + 12 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 16 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 20 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $0 + 24 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  $1 = $0 + $2 | 0;
-  wasm2js_i32$0 = $1 - 28 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 24 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 20 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  wasm2js_i32$0 = $1 - 16 | 0;
-  wasm2js_i32$1 = 0;
-  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  $1 = ($0 & 4 | 0) + 24 | 0;
-  $0 = $1 + $0 | 0;
-  $2 = $2 - $1 | 0;
-  continue_0 : do {
-   if ($2 >>> 0 >= 32 >>> 0) {
-    i64toi32_i32$1 = $0;
-    i64toi32_i32$0 = 0;
-    wasm2js_i32$0 = $0;
-    wasm2js_i32$1 = 0;
-    HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-    wasm2js_i32$0 = $0;
-    wasm2js_i32$1 = i64toi32_i32$0;
-    (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
-    i64toi32_i32$1 = $0 + 8 | 0;
-    i64toi32_i32$0 = 0;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = 0;
-    HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = i64toi32_i32$0;
-    (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
-    i64toi32_i32$1 = $0 + 16 | 0;
-    i64toi32_i32$0 = 0;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = 0;
-    HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = i64toi32_i32$0;
-    (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
-    i64toi32_i32$1 = $0 + 24 | 0;
-    i64toi32_i32$0 = 0;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = 0;
-    HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-    wasm2js_i32$0 = i64toi32_i32$1;
-    wasm2js_i32$1 = i64toi32_i32$0;
-    (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
-    $2 = $2 - 32 | 0;
-    $0 = $0 + 32 | 0;
-    continue continue_0;
-   }
-   break continue_0;
-  } while (1);
+  $lib_util_memory_memset_inlined_0 : {
+   wasm2js_i32$0 = $0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   $1 = $0 + 20 | 0;
+   wasm2js_i32$0 = $1 - 1 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 1 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 2 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 2 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 3 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 3 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 4 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP8[wasm2js_i32$0 >> 0] = wasm2js_i32$1;
+   $1 = (0 - $0 | 0) & 3 | 0;
+   $2 = 20 - $1 | 0;
+   $0 = $0 + $1 | 0;
+   wasm2js_i32$0 = $0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   $2 = $2 & 4294967292 | 0;
+   wasm2js_i32$0 = ($2 + $0 | 0) - 4 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   if ($2 >>> 0 <= 8 >>> 0) break $lib_util_memory_memset_inlined_0;
+   wasm2js_i32$0 = $0 + 4 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 8 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   $1 = $0 + $2 | 0;
+   wasm2js_i32$0 = $1 - 12 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 8 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   if ($2 >>> 0 <= 24 >>> 0) break $lib_util_memory_memset_inlined_0;
+   wasm2js_i32$0 = $0 + 12 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 16 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 20 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $0 + 24 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   $1 = $0 + $2 | 0;
+   wasm2js_i32$0 = $1 - 28 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 24 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 20 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   wasm2js_i32$0 = $1 - 16 | 0;
+   wasm2js_i32$1 = 0;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+   $1 = ($0 & 4 | 0) + 24 | 0;
+   $0 = $1 + $0 | 0;
+   $2 = $2 - $1 | 0;
+   continue_0 : do {
+    if ($2 >>> 0 >= 32 >>> 0) {
+     i64toi32_i32$1 = $0;
+     i64toi32_i32$0 = 0;
+     wasm2js_i32$0 = $0;
+     wasm2js_i32$1 = 0;
+     HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+     wasm2js_i32$0 = $0;
+     wasm2js_i32$1 = i64toi32_i32$0;
+     (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
+     i64toi32_i32$1 = $0 + 8 | 0;
+     i64toi32_i32$0 = 0;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = 0;
+     HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = i64toi32_i32$0;
+     (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
+     i64toi32_i32$1 = $0 + 16 | 0;
+     i64toi32_i32$0 = 0;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = 0;
+     HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = i64toi32_i32$0;
+     (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
+     i64toi32_i32$1 = $0 + 24 | 0;
+     i64toi32_i32$0 = 0;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = 0;
+     HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+     wasm2js_i32$0 = i64toi32_i32$1;
+     wasm2js_i32$1 = i64toi32_i32$0;
+     (wasm2js_i32$2 = wasm2js_i32$0, wasm2js_i32$3 = wasm2js_i32$1), ((HEAP8[(wasm2js_i32$2 + 4 | 0) >> 0] = wasm2js_i32$3 & 255 | 0, HEAP8[(wasm2js_i32$2 + 5 | 0) >> 0] = (wasm2js_i32$3 >>> 8 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 6 | 0) >> 0] = (wasm2js_i32$3 >>> 16 | 0) & 255 | 0), HEAP8[(wasm2js_i32$2 + 7 | 0) >> 0] = (wasm2js_i32$3 >>> 24 | 0) & 255 | 0;
+     $2 = $2 - 32 | 0;
+     $0 = $0 + 32 | 0;
+     continue continue_0;
+    }
+    break continue_0;
+   } while (1);
+  };
  }
  
- function $lib_array_Array_Body__constructor() {
-  var $0 = 0, $1 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
-  $1 = $lib_allocator_arena___memory_allocate(32 | 0) | 0;
-  wasm2js_i32$0 = $1;
-  wasm2js_i32$1 = 20;
+ function $lib_runtime_ArrayBufferView_constructor($0) {
+  $0 = $0 | 0;
+  var $1 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
+  $1 = $lib_runtime_doAllocate(20 | 0) | 0;
+  $lib_memory_memory_fill($1 | 0);
+  wasm2js_i32$0 = $1 - 8 | 0;
+  wasm2js_i32$1 = 4;
   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
-  $0 = $lib_allocator_arena___memory_allocate(8 | 0) | 0;
+  if (($0 | 0) == (0 | 0)) {
+   $0 = $lib_runtime_doAllocate(12 | 0) | 0;
+   wasm2js_i32$0 = $0 - 8 | 0;
+   wasm2js_i32$1 = 5;
+   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+  }
   wasm2js_i32$0 = $0;
   wasm2js_i32$1 = 0;
   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
@@ -244,38 +271,55 @@ function asmFunc(global, env, buffer) {
   wasm2js_i32$1 = 0;
   HEAP32[(wasm2js_i32$0 + 4 | 0) >> 2] = wasm2js_i32$1;
   wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = 0;
+  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
   wasm2js_i32$1 = $1;
   HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
   wasm2js_i32$0 = $0;
-  wasm2js_i32$1 = 5;
+  wasm2js_i32$1 = $1;
   HEAP32[(wasm2js_i32$0 + 4 | 0) >> 2] = wasm2js_i32$1;
-  $lib_internal_memory_memset($1 + 8 | 0 | 0);
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = 20;
+  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
+  return $0 | 0;
+ }
+ 
+ function $lib_array_Array_Body__constructor() {
+  var $0 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
+  $0 = $lib_runtime_doAllocate(16 | 0) | 0;
+  wasm2js_i32$0 = $0 - 8 | 0;
+  wasm2js_i32$1 = 6;
+  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+  $0 = $lib_runtime_ArrayBufferView_constructor($0 | 0) | 0;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = 0;
+  HEAP32[(wasm2js_i32$0 + 12 | 0) >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = 5;
+  HEAP32[(wasm2js_i32$0 + 12 | 0) >> 2] = wasm2js_i32$1;
   return $0 | 0;
  }
  
  function assembly_index_init() {
   var $0 = 0, $1 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
   $1 = $lib_array_Array_Body__constructor() | 0;
-  $0 = assembly_index_Body_constructor(+(0.0), +(0.0), +(0.0), +(0.0), +(0.0), +(0.0), +(39.47841760435743)) | 0;
-  wasm2js_i32$0 = HEAPU32[$1 >> 2] | 0;
-  wasm2js_i32$1 = $0;
-  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
-  $0 = assembly_index_Body_constructor(+(4.841431442464721), +(-1.1603200440274284), +(-.10362204447112311), +(.606326392995832), +(2.81198684491626), +(-.02521836165988763), +(.03769367487038949)) | 0;
-  wasm2js_i32$0 = (HEAPU32[$1 >> 2] | 0) + 4 | 0;
-  wasm2js_i32$1 = $0;
-  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
-  $0 = assembly_index_Body_constructor(+(8.34336671824458), +(4.124798564124305), +(-.4035234171143214), +(-1.0107743461787924), +(1.8256623712304119), +(.008415761376584154), +(.011286326131968767)) | 0;
-  wasm2js_i32$0 = (HEAPU32[$1 >> 2] | 0) + 8 | 0;
-  wasm2js_i32$1 = $0;
-  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
-  $0 = assembly_index_Body_constructor(+(12.894369562139131), +(-15.111151401698631), +(-.22330757889265573), +(1.0827910064415354), +(.8687130181696082), +(-.010832637401363636), +(1.7237240570597112e-03)) | 0;
-  wasm2js_i32$0 = (HEAPU32[$1 >> 2] | 0) + 12 | 0;
-  wasm2js_i32$1 = $0;
-  HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
-  $0 = assembly_index_Body_constructor(+(15.379697114850917), +(-25.919314609987964), +(.17925877295037118), +(.979090732243898), +(.5946989986476762), +(-.034755955504078104), +(2.0336868699246304e-03)) | 0;
-  wasm2js_i32$0 = (HEAPU32[$1 >> 2] | 0) + 16 | 0;
-  wasm2js_i32$1 = $0;
+  $0 = HEAPU32[($1 + 4 | 0) >> 2] | 0;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = assembly_index_Body_constructor(+(0.0), +(0.0), +(0.0), +(0.0), +(0.0), +(0.0), +(39.47841760435743)) | 0;
+  HEAP32[wasm2js_i32$0 >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = assembly_index_Body_constructor(+(4.841431442464721), +(-1.1603200440274284), +(-.10362204447112311), +(.606326392995832), +(2.81198684491626), +(-.02521836165988763), +(.03769367487038949)) | 0;
+  HEAP32[(wasm2js_i32$0 + 4 | 0) >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = assembly_index_Body_constructor(+(8.34336671824458), +(4.124798564124305), +(-.4035234171143214), +(-1.0107743461787924), +(1.8256623712304119), +(.008415761376584154), +(.011286326131968767)) | 0;
   HEAP32[(wasm2js_i32$0 + 8 | 0) >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = assembly_index_Body_constructor(+(12.894369562139131), +(-15.111151401698631), +(-.22330757889265573), +(1.0827910064415354), +(.8687130181696082), +(-.010832637401363636), +(1.7237240570597112e-03)) | 0;
+  HEAP32[(wasm2js_i32$0 + 12 | 0) >> 2] = wasm2js_i32$1;
+  wasm2js_i32$0 = $0;
+  wasm2js_i32$1 = assembly_index_Body_constructor(+(15.379697114850917), +(-25.919314609987964), +(.17925877295037118), +(.979090732243898), +(.5946989986476762), +(-.034755955504078104), +(2.0336868699246304e-03)) | 0;
+  HEAP32[(wasm2js_i32$0 + 16 | 0) >> 2] = wasm2js_i32$1;
   assembly_index_system = assembly_index_NBodySystem_constructor($1 | 0) | 0;
  }
  
@@ -283,10 +327,10 @@ function asmFunc(global, env, buffer) {
   $0 = $0 | 0;
   var $1 = 0, $2 = 0.0, $8 = 0.0, $3 = 0, $4 = 0.0, $5 = 0.0, $6 = 0.0, $7 = 0, $9 = 0.0, $10 = 0.0, $11 = 0.0, $12 = 0, $13 = 0, $18 = 0.0, $14 = 0.0, $15 = 0.0, $16 = 0.0, $17 = 0.0, wasm2js_i32$0 = 0, wasm2js_f64$0 = 0.0;
   $12 = HEAPU32[$0 >> 2] | 0;
-  $13 = HEAP32[($12 + 4 | 0) >> 2] | 0;
+  $13 = HEAP32[($12 + 12 | 0) >> 2] | 0;
   repeat_0 : do {
    if ($3 >>> 0 < $13 >>> 0) {
-    $0 = HEAPU32[(((HEAPU32[$12 >> 2] | 0) + ($3 << 2 | 0) | 0) + 8 | 0) >> 2] | 0;
+    $0 = HEAPU32[((HEAP32[($12 + 4 | 0) >> 2] | 0) + ($3 << 2 | 0) | 0) >> 2] | 0;
     $14 = +HEAPF64[$0 >> 3];
     $15 = +HEAPF64[($0 + 8 | 0) >> 3];
     $16 = +HEAPF64[($0 + 16 | 0) >> 3];
@@ -297,7 +341,7 @@ function asmFunc(global, env, buffer) {
     $7 = $3 + 1 | 0;
     repeat_1 : do {
      if ($7 >>> 0 < $13 >>> 0) {
-      $1 = HEAPU32[(((HEAPU32[$12 >> 2] | 0) + ($7 << 2 | 0) | 0) + 8 | 0) >> 2] | 0;
+      $1 = HEAPU32[((HEAP32[($12 + 4 | 0) >> 2] | 0) + ($7 << 2 | 0) | 0) >> 2] | 0;
       $18 = $14 - +HEAPF64[$1 >> 3];
       $2 = $18;
       $9 = $15 - +HEAPF64[($1 + 8 | 0) >> 3];
@@ -351,33 +395,35 @@ function asmFunc(global, env, buffer) {
  
  function assembly_index_NBodySystem_energy($0) {
   $0 = $0 | 0;
-  var $1 = 0.0, $2 = 0, $3 = 0, $4 = 0, $5 = 0, $10 = 0.0, $6 = 0.0, $7 = 0.0, $8 = 0.0, $9 = 0.0, $30 = 0.0, $39 = 0.0, $45 = 0.0, $69 = 0.0, $84 = 0.0;
+  var $1 = 0.0, $2 = 0, $3 = 0, $4 = 0, $5 = 0, $9 = 0.0, $6 = 0.0, $7 = 0.0, $8 = 0.0, $30 = 0.0, $39 = 0.0, $45 = 0.0, $10 = 0.0, $72 = 0.0, $86 = 0.0;
   $4 = HEAPU32[$0 >> 2] | 0;
-  $5 = HEAP32[($4 + 4 | 0) >> 2] | 0;
+  $5 = HEAP32[($4 + 12 | 0) >> 2] | 0;
   repeat_0 : do {
    if ($2 >>> 0 < $5 >>> 0) {
-    $0 = HEAPU32[(((HEAPU32[$4 >> 2] | 0) + ($2 << 2 | 0) | 0) + 8 | 0) >> 2] | 0;
-    $7 = +HEAPF64[$0 >> 3];
-    $8 = +HEAPF64[($0 + 8 | 0) >> 3];
-    $9 = +HEAPF64[($0 + 16 | 0) >> 3];
+    $0 = HEAPU32[((HEAP32[($4 + 4 | 0) >> 2] | 0) + ($2 << 2 | 0) | 0) >> 2] | 0;
+    $6 = +HEAPF64[$0 >> 3];
+    $7 = +HEAPF64[($0 + 8 | 0) >> 3];
+    $8 = +HEAPF64[($0 + 16 | 0) >> 3];
     $30 = $1;
-    $10 = +HEAPF64[($0 + 48 | 0) >> 3];
+    $9 = +HEAPF64[($0 + 48 | 0) >> 3];
     $1 = +HEAPF64[($0 + 24 | 0) >> 3];
     $39 = $1 * $1;
     $1 = +HEAPF64[($0 + 32 | 0) >> 3];
     $45 = $39 + $1 * $1;
     $1 = +HEAPF64[($0 + 40 | 0) >> 3];
-    $1 = $30 + .5 * $10 * ($45 + $1 * $1);
+    $1 = $30 + .5 * $9 * ($45 + $1 * $1);
     $0 = $2 + 1 | 0;
     repeat_1 : do {
      if ($0 >>> 0 < $5 >>> 0) {
-      $3 = HEAPU32[(((HEAPU32[$4 >> 2] | 0) + ($0 << 2 | 0) | 0) + 8 | 0) >> 2] | 0;
-      $6 = $7 - +HEAPF64[$3 >> 3];
-      $69 = $1;
-      $1 = $8 - +HEAPF64[($3 + 8 | 0) >> 3];
-      $84 = $6 * $6 + $1 * $1;
-      $1 = $9 - +HEAPF64[($3 + 16 | 0) >> 3];
-      $1 = $69 - $10 * +HEAPF64[($3 + 48 | 0) >> 3] / Math_sqrt($84 + $1 * $1);
+      $10 = $1;
+      $3 = HEAPU32[((HEAP32[($4 + 4 | 0) >> 2] | 0) + ($0 << 2 | 0) | 0) >> 2] | 0;
+      $1 = $6 - +HEAPF64[$3 >> 3];
+      $72 = $1 * $1;
+      $1 = $7 - +HEAPF64[($3 + 8 | 0) >> 3];
+      $1 = $72 + $1 * $1;
+      $86 = $1;
+      $1 = $8 - +HEAPF64[($3 + 16 | 0) >> 3];
+      $1 = $10 - $9 * +HEAPF64[($3 + 48 | 0) >> 3] / Math_sqrt($86 + $1 * $1);
       $0 = $0 + 1 | 0;
       continue repeat_1;
      }
@@ -412,18 +458,14 @@ function asmFunc(global, env, buffer) {
  
  function assembly_index_getBody($0) {
   $0 = $0 | 0;
-  var $1 = 0, $22 = 0, $20 = 0;
+  var $1 = 0, $14 = 0;
   $1 = HEAPU32[assembly_index_system >> 2] | 0;
-  if ($0 >>> 0 < (HEAP32[($1 + 4 | 0) >> 2] | 0) >>> 0) {
-   $1 = HEAPU32[$1 >> 2] | 0;
-   if ($0 >>> 0 < ((HEAP32[$1 >> 2] | 0) >>> 2 | 0) >>> 0) $20 = HEAPU32[((($0 << 2 | 0) + $1 | 0) + 8 | 0) >> 2] | 0; else abort();
-   $22 = $20;
-  } else $22 = 0;
-  return $22 | 0;
+  if ($0 >>> 0 < (HEAP32[($1 + 12 | 0) >> 2] | 0) >>> 0) $14 = HEAPU32[((HEAP32[($1 + 4 | 0) >> 2] | 0) + ($0 << 2 | 0) | 0) >> 2] | 0; else $14 = 0;
+  return $14 | 0;
  }
  
  function start() {
-  $lib_allocator_arena_startOffset = 40;
+  $lib_allocator_arena_startOffset = 96;
   $lib_allocator_arena_offset = $lib_allocator_arena_startOffset;
  }
  
@@ -493,7 +535,8 @@ const assignasmFunc = (
         }
       }
     )(memasmFunc);
-assignasmFunc(8, "DQAAAH4AbABpAGIALwBhAHIAcgBhAHkALgB0AHM=");
+assignasmFunc(8, "AwAAAB4AAAB+AGwAaQBiAC8AcgB1AG4AdABpAG0AZQAuAHQAcw==");
+assignasmFunc(48, "AwAAACYAAAB+AGwAaQBiAC8AYQByAHIAYQB5AGIAdQBmAGYAZQByAC4AdABz");
 const retasmFunc = asmFunc({Math,Int8Array,Uint8Array,Int16Array,Uint16Array,Int32Array,Uint32Array,Float32Array,Float64Array,NaN,Infinity}, {abort:function() { throw new Error('abort'); }},memasmFunc);
 export const memory = retasmFunc.memory;
 export const init = retasmFunc.init;
diff --git a/examples/n-body/build/optimized.wasm b/examples/n-body/build/optimized.wasm
index e299a576..8405b87c 100644
Binary files a/examples/n-body/build/optimized.wasm and b/examples/n-body/build/optimized.wasm differ
diff --git a/examples/n-body/build/optimized.wat b/examples/n-body/build/optimized.wat
index de9adc85..b11978f3 100644
--- a/examples/n-body/build/optimized.wat
+++ b/examples/n-body/build/optimized.wat
@@ -7,12 +7,13 @@
  (type $FUNCSIG$iddddddd (func (param f64 f64 f64 f64 f64 f64 f64) (result i32)))
  (type $FUNCSIG$i (func (result i32)))
  (import "env" "memory" (memory $0 1))
- (data (i32.const 8) "\0d\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s")
+ (data (i32.const 8) "\03\00\00\00\1e\00\00\00~\00l\00i\00b\00/\00r\00u\00n\00t\00i\00m\00e\00.\00t\00s")
+ (data (i32.const 48) "\03\00\00\00&\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00b\00u\00f\00f\00e\00r\00.\00t\00s")
  (table $0 1 funcref)
  (elem (i32.const 0) $null)
+ (global $assembly/index/system (mut i32) (i32.const 0))
  (global $~lib/allocator/arena/startOffset (mut i32) (i32.const 0))
  (global $~lib/allocator/arena/offset (mut i32) (i32.const 0))
- (global $assembly/index/system (mut i32) (i32.const 0))
  (export "memory" (memory $0))
  (export "table" (table $0))
  (export "init" (func $assembly/index/init))
@@ -20,7 +21,7 @@
  (export "bench" (func $assembly/index/bench))
  (export "getBody" (func $assembly/index/getBody))
  (start $start)
- (func $~lib/allocator/arena/__memory_allocate (; 0 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+ (func $~lib/memory/memory.allocate (; 0 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
   (local $2 i32)
   (local $3 i32)
@@ -43,15 +44,15 @@
   i32.add
   i32.const -8
   i32.and
-  local.tee $2
+  local.tee $0
   current_memory
-  local.tee $3
+  local.tee $2
   i32.const 16
   i32.shl
   i32.gt_u
   if
-   local.get $3
    local.get $2
+   local.get $0
    local.get $1
    i32.sub
    i32.const 65535
@@ -60,16 +61,16 @@
    i32.and
    i32.const 16
    i32.shr_u
-   local.tee $0
+   local.tee $3
+   local.get $2
    local.get $3
-   local.get $0
    i32.gt_s
    select
    grow_memory
    i32.const 0
    i32.lt_s
    if
-    local.get $0
+    local.get $3
     grow_memory
     i32.const 0
     i32.lt_s
@@ -78,11 +79,32 @@
     end
    end
   end
-  local.get $2
+  local.get $0
   global.set $~lib/allocator/arena/offset
   local.get $1
  )
- (func $assembly/index/NBodySystem#constructor (; 1 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+ (func $~lib/runtime/doAllocate (; 1 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+  (local $1 i32)
+  i32.const 1
+  i32.const 32
+  local.get $0
+  i32.const 7
+  i32.add
+  i32.clz
+  i32.sub
+  i32.shl
+  call $~lib/memory/memory.allocate
+  local.tee $1
+  i32.const -1520547049
+  i32.store
+  local.get $1
+  local.get $0
+  i32.store offset=4
+  local.get $1
+  i32.const 8
+  i32.add
+ )
+ (func $assembly/index/NBodySystem#constructor (; 2 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
   (local $2 i32)
   (local $3 f64)
@@ -91,7 +113,7 @@
   (local $6 f64)
   (local $7 i32)
   local.get $0
-  i32.load offset=4
+  i32.load offset=12
   local.set $7
   loop $repeat|0
    local.get $1
@@ -99,12 +121,12 @@
    i32.lt_s
    if
     local.get $0
-    i32.load
+    i32.load offset=4
     local.get $1
     i32.const 2
     i32.shl
     i32.add
-    i32.load offset=8
+    i32.load
     local.tee $2
     f64.load offset=48
     local.set $3
@@ -136,21 +158,10 @@
     br $repeat|0
    end
   end
-  i32.const 0
   local.get $0
+  i32.load offset=4
   i32.load
   local.tee $1
-  i32.load
-  i32.const 2
-  i32.shr_u
-  i32.lt_u
-  if (result i32)
-   local.get $1
-   i32.load offset=8
-  else   
-   unreachable
-  end
-  local.tee $1
   local.get $4
   f64.neg
   f64.const 39.47841760435743
@@ -169,17 +180,27 @@
   f64.div
   f64.store offset=40
   i32.const 4
-  call $~lib/allocator/arena/__memory_allocate
+  call $~lib/runtime/doAllocate
   local.tee $1
+  i32.const 8
+  i32.sub
+  i32.const 1
+  i32.store
+  local.get $1
   local.get $0
   i32.store
   local.get $1
  )
- (func $assembly/index/Body#constructor (; 2 ;) (type $FUNCSIG$iddddddd) (param $0 f64) (param $1 f64) (param $2 f64) (param $3 f64) (param $4 f64) (param $5 f64) (param $6 f64) (result i32)
+ (func $assembly/index/Body#constructor (; 3 ;) (type $FUNCSIG$iddddddd) (param $0 f64) (param $1 f64) (param $2 f64) (param $3 f64) (param $4 f64) (param $5 f64) (param $6 f64) (result i32)
   (local $7 i32)
   i32.const 56
-  call $~lib/allocator/arena/__memory_allocate
+  call $~lib/runtime/doAllocate
   local.tee $7
+  i32.const 8
+  i32.sub
+  i32.const 2
+  i32.store
+  local.get $7
   local.get $0
   f64.store
   local.get $7
@@ -202,232 +223,267 @@
   f64.store offset=48
   local.get $7
  )
- (func $~lib/internal/memory/memset (; 3 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/memory/memory.fill (; 4 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   (local $2 i32)
-  local.get $0
-  i32.const 0
-  i32.store8
-  local.get $0
-  i32.const 20
-  i32.add
-  local.tee $1
-  i32.const 1
-  i32.sub
-  i32.const 0
-  i32.store8
-  local.get $0
-  i32.const 1
-  i32.add
-  i32.const 0
-  i32.store8
-  local.get $0
-  i32.const 2
-  i32.add
-  i32.const 0
-  i32.store8
-  local.get $1
-  i32.const 2
-  i32.sub
-  i32.const 0
-  i32.store8
-  local.get $1
-  i32.const 3
-  i32.sub
-  i32.const 0
-  i32.store8
-  local.get $0
-  i32.const 3
-  i32.add
-  i32.const 0
-  i32.store8
-  local.get $1
-  i32.const 4
-  i32.sub
-  i32.const 0
-  i32.store8
-  i32.const 0
-  local.get $0
-  i32.sub
-  i32.const 3
-  i32.and
-  local.tee $1
-  local.get $0
-  i32.add
-  local.tee $0
-  i32.const 0
-  i32.store
-  i32.const 20
-  local.get $1
-  i32.sub
-  i32.const -4
-  i32.and
-  local.tee $2
-  local.get $0
-  i32.add
-  i32.const 4
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $2
-  i32.const 8
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 4
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  i32.const 8
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  local.tee $1
-  i32.const 12
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $1
-  i32.const 8
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $2
-  i32.const 24
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 12
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  i32.const 16
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  i32.const 20
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  i32.const 24
-  i32.add
-  i32.const 0
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  local.tee $1
-  i32.const 28
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $1
-  i32.const 24
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $1
-  i32.const 20
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $1
-  i32.const 16
-  i32.sub
-  i32.const 0
-  i32.store
-  local.get $0
-  i32.const 4
-  i32.and
-  i32.const 24
-  i32.add
-  local.tee $1
-  local.get $0
-  i32.add
-  local.set $0
-  local.get $2
-  local.get $1
-  i32.sub
-  local.set $2
-  loop $continue|0
+  block $~lib/util/memory/memset|inlined.0
+   local.get $0
+   i32.const 0
+   i32.store8
+   local.get $0
+   i32.const 20
+   i32.add
+   local.tee $1
+   i32.const 1
+   i32.sub
+   i32.const 0
+   i32.store8
+   local.get $0
+   i32.const 1
+   i32.add
+   i32.const 0
+   i32.store8
+   local.get $0
+   i32.const 2
+   i32.add
+   i32.const 0
+   i32.store8
+   local.get $1
+   i32.const 2
+   i32.sub
+   i32.const 0
+   i32.store8
+   local.get $1
+   i32.const 3
+   i32.sub
+   i32.const 0
+   i32.store8
+   local.get $0
+   i32.const 3
+   i32.add
+   i32.const 0
+   i32.store8
+   local.get $1
+   i32.const 4
+   i32.sub
+   i32.const 0
+   i32.store8
+   i32.const 20
+   i32.const 0
+   local.get $0
+   i32.sub
+   i32.const 3
+   i32.and
+   local.tee $1
+   i32.sub
+   local.set $2
+   local.get $0
+   local.get $1
+   i32.add
+   local.tee $0
+   i32.const 0
+   i32.store
    local.get $2
-   i32.const 32
-   i32.ge_u
-   if
-    local.get $0
-    i64.const 0
-    i64.store
-    local.get $0
-    i32.const 8
-    i32.add
-    i64.const 0
-    i64.store
-    local.get $0
-    i32.const 16
-    i32.add
-    i64.const 0
-    i64.store
-    local.get $0
-    i32.const 24
-    i32.add
-    i64.const 0
-    i64.store
+   i32.const -4
+   i32.and
+   local.tee $2
+   local.get $0
+   i32.add
+   i32.const 4
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $2
+   i32.const 8
+   i32.le_u
+   br_if $~lib/util/memory/memset|inlined.0
+   local.get $0
+   i32.const 4
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 8
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   local.tee $1
+   i32.const 12
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $1
+   i32.const 8
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $2
+   i32.const 24
+   i32.le_u
+   br_if $~lib/util/memory/memset|inlined.0
+   local.get $0
+   i32.const 12
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 16
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 20
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 24
+   i32.add
+   i32.const 0
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   local.tee $1
+   i32.const 28
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $1
+   i32.const 24
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $1
+   i32.const 20
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $1
+   i32.const 16
+   i32.sub
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 4
+   i32.and
+   i32.const 24
+   i32.add
+   local.tee $1
+   local.get $0
+   i32.add
+   local.set $0
+   local.get $2
+   local.get $1
+   i32.sub
+   local.set $2
+   loop $continue|0
     local.get $2
     i32.const 32
-    i32.sub
-    local.set $2
-    local.get $0
-    i32.const 32
-    i32.add
-    local.set $0
-    br $continue|0
+    i32.ge_u
+    if
+     local.get $0
+     i64.const 0
+     i64.store
+     local.get $0
+     i32.const 8
+     i32.add
+     i64.const 0
+     i64.store
+     local.get $0
+     i32.const 16
+     i32.add
+     i64.const 0
+     i64.store
+     local.get $0
+     i32.const 24
+     i32.add
+     i64.const 0
+     i64.store
+     local.get $2
+     i32.const 32
+     i32.sub
+     local.set $2
+     local.get $0
+     i32.const 32
+     i32.add
+     local.set $0
+     br $continue|0
+    end
    end
   end
  )
- (func $~lib/array/Array<Body>#constructor (; 4 ;) (type $FUNCSIG$i) (result i32)
-  (local $0 i32)
+ (func $~lib/runtime/ArrayBufferView#constructor (; 5 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
-  i32.const 32
-  call $~lib/allocator/arena/__memory_allocate
-  local.tee $1
   i32.const 20
-  i32.store
+  call $~lib/runtime/doAllocate
+  local.tee $1
+  call $~lib/memory/memory.fill
+  local.get $1
   i32.const 8
-  call $~lib/allocator/arena/__memory_allocate
-  local.tee $0
+  i32.sub
+  i32.const 4
+  i32.store
+  local.get $0
+  i32.eqz
+  if
+   i32.const 12
+   call $~lib/runtime/doAllocate
+   local.tee $0
+   i32.const 8
+   i32.sub
+   i32.const 5
+   i32.store
+  end
+  local.get $0
   i32.const 0
   i32.store
   local.get $0
   i32.const 0
   i32.store offset=4
   local.get $0
+  i32.const 0
+  i32.store offset=8
+  local.get $0
   local.get $1
   i32.store
   local.get $0
-  i32.const 5
-  i32.store offset=4
   local.get $1
-  i32.const 8
-  i32.add
-  call $~lib/internal/memory/memset
+  i32.store offset=4
+  local.get $0
+  i32.const 20
+  i32.store offset=8
   local.get $0
  )
- (func $assembly/index/init (; 5 ;) (type $FUNCSIG$v)
+ (func $~lib/array/Array<Body>#constructor (; 6 ;) (type $FUNCSIG$i) (result i32)
+  (local $0 i32)
+  i32.const 16
+  call $~lib/runtime/doAllocate
+  local.tee $0
+  i32.const 8
+  i32.sub
+  i32.const 6
+  i32.store
+  local.get $0
+  call $~lib/runtime/ArrayBufferView#constructor
+  local.tee $0
+  i32.const 0
+  i32.store offset=12
+  local.get $0
+  i32.const 5
+  i32.store offset=12
+  local.get $0
+ )
+ (func $assembly/index/init (; 7 ;) (type $FUNCSIG$v)
   (local $0 i32)
   (local $1 i32)
   call $~lib/array/Array<Body>#constructor
-  local.set $1
+  local.tee $1
+  i32.load offset=4
+  local.tee $0
   f64.const 0
   f64.const 0
   f64.const 0
@@ -436,11 +492,8 @@
   f64.const 0
   f64.const 39.47841760435743
   call $assembly/index/Body#constructor
-  local.set $0
-  local.get $1
-  i32.load
+  i32.store
   local.get $0
-  i32.store offset=8
   f64.const 4.841431442464721
   f64.const -1.1603200440274284
   f64.const -0.10362204447112311
@@ -449,13 +502,8 @@
   f64.const -0.02521836165988763
   f64.const 0.03769367487038949
   call $assembly/index/Body#constructor
-  local.set $0
-  local.get $1
-  i32.load
-  i32.const 4
-  i32.add
+  i32.store offset=4
   local.get $0
-  i32.store offset=8
   f64.const 8.34336671824458
   f64.const 4.124798564124305
   f64.const -0.4035234171143214
@@ -464,13 +512,8 @@
   f64.const 0.008415761376584154
   f64.const 0.011286326131968767
   call $assembly/index/Body#constructor
-  local.set $0
-  local.get $1
-  i32.load
-  i32.const 8
-  i32.add
-  local.get $0
   i32.store offset=8
+  local.get $0
   f64.const 12.894369562139131
   f64.const -15.111151401698631
   f64.const -0.22330757889265573
@@ -479,13 +522,8 @@
   f64.const -0.010832637401363636
   f64.const 1.7237240570597112e-03
   call $assembly/index/Body#constructor
-  local.set $0
-  local.get $1
-  i32.load
-  i32.const 12
-  i32.add
+  i32.store offset=12
   local.get $0
-  i32.store offset=8
   f64.const 15.379697114850917
   f64.const -25.919314609987964
   f64.const 0.17925877295037118
@@ -494,18 +532,12 @@
   f64.const -0.034755955504078104
   f64.const 2.0336868699246304e-03
   call $assembly/index/Body#constructor
-  local.set $0
-  local.get $1
-  i32.load
-  i32.const 16
-  i32.add
-  local.get $0
-  i32.store offset=8
+  i32.store offset=16
   local.get $1
   call $assembly/index/NBodySystem#constructor
   global.set $assembly/index/system
  )
- (func $assembly/index/NBodySystem#advance (; 6 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $assembly/index/NBodySystem#advance (; 8 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   (local $2 f64)
   (local $3 i32)
@@ -527,7 +559,7 @@
   local.get $0
   i32.load
   local.tee $12
-  i32.load offset=4
+  i32.load offset=12
   local.set $13
   loop $repeat|0
    local.get $3
@@ -535,12 +567,12 @@
    i32.lt_u
    if
     local.get $12
-    i32.load
+    i32.load offset=4
     local.get $3
     i32.const 2
     i32.shl
     i32.add
-    i32.load offset=8
+    i32.load
     local.tee $0
     f64.load
     local.set $14
@@ -573,12 +605,12 @@
      if
       local.get $14
       local.get $12
-      i32.load
+      i32.load offset=4
       local.get $7
       i32.const 2
       i32.shl
       i32.add
-      i32.load offset=8
+      i32.load
       local.tee $1
       f64.load
       f64.sub
@@ -707,7 +739,7 @@
    end
   end
  )
- (func $assembly/index/NBodySystem#energy (; 7 ;) (type $FUNCSIG$di) (param $0 i32) (result f64)
+ (func $assembly/index/NBodySystem#energy (; 9 ;) (type $FUNCSIG$di) (param $0 i32) (result f64)
   (local $1 f64)
   (local $2 i32)
   (local $3 i32)
@@ -721,7 +753,7 @@
   local.get $0
   i32.load
   local.tee $4
-  i32.load offset=4
+  i32.load offset=12
   local.set $5
   loop $repeat|0
    local.get $2
@@ -729,26 +761,26 @@
    i32.lt_u
    if
     local.get $4
-    i32.load
+    i32.load offset=4
     local.get $2
     i32.const 2
     i32.shl
     i32.add
-    i32.load offset=8
+    i32.load
     local.tee $0
     f64.load
-    local.set $7
+    local.set $6
     local.get $0
     f64.load offset=8
-    local.set $8
+    local.set $7
     local.get $0
     f64.load offset=16
-    local.set $9
+    local.set $8
     local.get $1
     f64.const 0.5
     local.get $0
     f64.load offset=48
-    local.tee $10
+    local.tee $9
     f64.mul
     local.get $0
     f64.load offset=24
@@ -779,27 +811,23 @@
      local.get $5
      i32.lt_u
      if
-      local.get $7
+      local.get $1
+      local.set $10
+      local.get $6
       local.get $4
-      i32.load
+      i32.load offset=4
       local.get $0
       i32.const 2
       i32.shl
       i32.add
-      i32.load offset=8
+      i32.load
       local.tee $3
       f64.load
       f64.sub
-      local.set $6
+      local.tee $1
       local.get $1
-      local.get $10
-      local.get $3
-      f64.load offset=48
       f64.mul
-      local.get $6
-      local.get $6
-      f64.mul
-      local.get $8
+      local.get $7
       local.get $3
       f64.load offset=8
       f64.sub
@@ -807,8 +835,15 @@
       local.get $1
       f64.mul
       f64.add
+      local.set $1
+      local.get $10
       local.get $9
       local.get $3
+      f64.load offset=48
+      f64.mul
+      local.get $1
+      local.get $8
+      local.get $3
       f64.load offset=16
       f64.sub
       local.tee $1
@@ -835,13 +870,13 @@
   end
   local.get $1
  )
- (func $assembly/index/step (; 8 ;) (type $FUNCSIG$d) (result f64)
+ (func $assembly/index/step (; 10 ;) (type $FUNCSIG$d) (result f64)
   global.get $assembly/index/system
   call $assembly/index/NBodySystem#advance
   global.get $assembly/index/system
   call $assembly/index/NBodySystem#energy
  )
- (func $assembly/index/bench (; 9 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $assembly/index/bench (; 11 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   block $break|0
    loop $repeat|0
@@ -861,44 +896,33 @@
    unreachable
   end
  )
- (func $assembly/index/getBody (; 10 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+ (func $assembly/index/getBody (; 12 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
   local.get $0
   global.get $assembly/index/system
   i32.load
   local.tee $1
-  i32.load offset=4
+  i32.load offset=12
   i32.lt_u
   if (result i32)
-   local.get $0
    local.get $1
-   i32.load
-   local.tee $1
-   i32.load
+   i32.load offset=4
+   local.get $0
    i32.const 2
-   i32.shr_u
-   i32.lt_u
-   if (result i32)
-    local.get $0
-    i32.const 2
-    i32.shl
-    local.get $1
-    i32.add
-    i32.load offset=8
-   else    
-    unreachable
-   end
+   i32.shl
+   i32.add
+   i32.load
   else   
    i32.const 0
   end
  )
- (func $start (; 11 ;) (type $FUNCSIG$v)
-  i32.const 40
+ (func $start (; 13 ;) (type $FUNCSIG$v)
+  i32.const 96
   global.set $~lib/allocator/arena/startOffset
   global.get $~lib/allocator/arena/startOffset
   global.set $~lib/allocator/arena/offset
  )
- (func $null (; 12 ;) (type $FUNCSIG$v)
+ (func $null (; 14 ;) (type $FUNCSIG$v)
   nop
  )
 )
diff --git a/examples/n-body/build/untouched.wat b/examples/n-body/build/untouched.wat
index 8077faee..0532282d 100644
--- a/examples/n-body/build/untouched.wat
+++ b/examples/n-body/build/untouched.wat
@@ -1,29 +1,35 @@
 (module
  (type $FUNCSIG$v (func))
  (type $FUNCSIG$iii (func (param i32 i32) (result i32)))
- (type $FUNCSIG$iiddd (func (param i32 f64 f64 f64) (result i32)))
  (type $FUNCSIG$ii (func (param i32) (result i32)))
+ (type $FUNCSIG$iiddd (func (param i32 f64 f64 f64) (result i32)))
+ (type $FUNCSIG$vi (func (param i32)))
+ (type $FUNCSIG$viiii (func (param i32 i32 i32 i32)))
  (type $FUNCSIG$i (func (result i32)))
  (type $FUNCSIG$iiddddddd (func (param i32 f64 f64 f64 f64 f64 f64 f64) (result i32)))
- (type $FUNCSIG$viiii (func (param i32 i32 i32 i32)))
+ (type $FUNCSIG$iiii (func (param i32 i32 i32) (result i32)))
  (type $FUNCSIG$viii (func (param i32 i32 i32)))
  (type $FUNCSIG$d (func (result f64)))
  (type $FUNCSIG$vid (func (param i32 f64)))
  (type $FUNCSIG$di (func (param i32) (result f64)))
- (type $FUNCSIG$vi (func (param i32)))
  (import "env" "memory" (memory $0 1))
- (data (i32.const 8) "\0d\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s\00")
- (data (i32.const 40) "\1c\00\00\00~\00l\00i\00b\00/\00i\00n\00t\00e\00r\00n\00a\00l\00/\00a\00r\00r\00a\00y\00b\00u\00f\00f\00e\00r\00.\00t\00s\00")
+ (data (i32.const 8) "\02\00\00\00\1e\00\00\00~\00l\00i\00b\00/\00r\00u\00n\00t\00i\00m\00e\00.\00t\00s\00")
+ (data (i32.const 48) "\02\00\00\00&\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00b\00u\00f\00f\00e\00r\00.\00t\00s\00")
  (import "env" "abort" (func $~lib/env/abort (param i32 i32 i32 i32)))
  (table $0 1 funcref)
  (elem (i32.const 0) $null)
- (global $~lib/allocator/arena/startOffset (mut i32) (i32.const 0))
- (global $~lib/allocator/arena/offset (mut i32) (i32.const 0))
  (global $~lib/math/NativeMath.PI f64 (f64.const 3.141592653589793))
  (global $assembly/index/SOLAR_MASS f64 (f64.const 39.47841760435743))
  (global $assembly/index/DAYS_PER_YEAR f64 (f64.const 365.24))
  (global $assembly/index/system (mut i32) (i32.const 0))
- (global $~lib/memory/HEAP_BASE i32 (i32.const 100))
+ (global $~lib/runtime/GC_IMPLEMENTED i32 (i32.const 0))
+ (global $~lib/runtime/HEADER_SIZE i32 (i32.const 8))
+ (global $~lib/runtime/HEADER_MAGIC i32 (i32.const -1520547049))
+ (global $~lib/allocator/arena/startOffset (mut i32) (i32.const 0))
+ (global $~lib/allocator/arena/offset (mut i32) (i32.const 0))
+ (global $~lib/ASC_NO_ASSERT i32 (i32.const 0))
+ (global $~lib/runtime/MAX_BYTELENGTH i32 (i32.const 1073741816))
+ (global $~lib/memory/HEAP_BASE i32 (i32.const 96))
  (export "memory" (memory $0))
  (export "table" (table $0))
  (export "init" (func $assembly/index/init))
@@ -31,75 +37,11 @@
  (export "bench" (func $assembly/index/bench))
  (export "getBody" (func $assembly/index/getBody))
  (start $start)
- (func $start:~lib/allocator/arena (; 1 ;) (type $FUNCSIG$v)
-  global.get $~lib/memory/HEAP_BASE
-  i32.const 7
-  i32.add
-  i32.const 7
-  i32.const -1
-  i32.xor
-  i32.and
-  global.set $~lib/allocator/arena/startOffset
-  global.get $~lib/allocator/arena/startOffset
-  global.set $~lib/allocator/arena/offset
- )
- (func $start:assembly/index (; 2 ;) (type $FUNCSIG$v)
-  call $start:~lib/allocator/arena
- )
- (func $~lib/array/Array<Body>#__unchecked_get (; 3 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
-  (local $2 i32)
-  (local $3 i32)
-  (local $4 i32)
+ (func $~lib/array/Array<Body>#get:length (; 1 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   local.get $0
-  i32.load
-  local.set $2
-  local.get $1
-  local.set $3
-  i32.const 0
-  local.set $4
-  local.get $2
-  local.get $3
-  i32.const 2
-  i32.shl
-  i32.add
-  local.get $4
-  i32.add
-  i32.load offset=8
+  i32.load offset=12
  )
- (func $~lib/array/Array<Body>#__get (; 4 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
-  (local $2 i32)
-  (local $3 i32)
-  (local $4 i32)
-  (local $5 i32)
-  local.get $0
-  i32.load
-  local.set $2
-  local.get $1
-  local.get $2
-  i32.load
-  i32.const 2
-  i32.shr_u
-  i32.lt_u
-  if (result i32)
-   local.get $2
-   local.set $3
-   local.get $1
-   local.set $4
-   i32.const 0
-   local.set $5
-   local.get $3
-   local.get $4
-   i32.const 2
-   i32.shl
-   i32.add
-   local.get $5
-   i32.add
-   i32.load offset=8
-  else   
-   unreachable
-  end
- )
- (func $assembly/index/Body#offsetMomentum (; 5 ;) (type $FUNCSIG$iiddd) (param $0 i32) (param $1 f64) (param $2 f64) (param $3 f64) (result i32)
+ (func $assembly/index/Body#offsetMomentum (; 2 ;) (type $FUNCSIG$iiddd) (param $0 i32) (param $1 f64) (param $2 f64) (param $3 f64) (result i32)
   local.get $0
   local.get $1
   f64.neg
@@ -120,91 +62,163 @@
   f64.store offset=40
   local.get $0
  )
- (func $~lib/allocator/arena/__memory_allocate (; 6 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+ (func $~lib/runtime/ADJUSTOBLOCK (; 3 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+  i32.const 1
+  i32.const 32
+  local.get $0
+  global.get $~lib/runtime/HEADER_SIZE
+  i32.add
+  i32.const 1
+  i32.sub
+  i32.clz
+  i32.sub
+  i32.shl
+ )
+ (func $~lib/memory/memory.allocate (; 4 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
   (local $2 i32)
   (local $3 i32)
   (local $4 i32)
   (local $5 i32)
   (local $6 i32)
-  local.get $0
-  i32.const 1073741824
-  i32.gt_u
-  if
-   unreachable
-  end
-  global.get $~lib/allocator/arena/offset
-  local.set $1
-  local.get $1
-  local.get $0
-  local.tee $2
-  i32.const 1
-  local.tee $3
-  local.get $2
-  local.get $3
-  i32.gt_u
-  select
-  i32.add
-  i32.const 7
-  i32.add
-  i32.const 7
-  i32.const -1
-  i32.xor
-  i32.and
-  local.set $4
-  current_memory
-  local.set $5
-  local.get $4
-  local.get $5
-  i32.const 16
-  i32.shl
-  i32.gt_u
-  if
-   local.get $4
+  (local $7 i32)
+  block $~lib/allocator/arena/__memory_allocate|inlined.0 (result i32)
+   local.get $0
+   local.set $1
    local.get $1
-   i32.sub
-   i32.const 65535
+   i32.const 1073741824
+   i32.gt_u
+   if
+    unreachable
+   end
+   global.get $~lib/allocator/arena/offset
+   local.set $2
+   local.get $2
+   local.get $1
+   local.tee $3
+   i32.const 1
+   local.tee $4
+   local.get $3
+   local.get $4
+   i32.gt_u
+   select
    i32.add
-   i32.const 65535
+   i32.const 7
+   i32.add
+   i32.const 7
    i32.const -1
    i32.xor
    i32.and
-   i32.const 16
-   i32.shr_u
-   local.set $2
-   local.get $5
-   local.tee $3
-   local.get $2
-   local.tee $6
-   local.get $3
-   local.get $6
-   i32.gt_s
-   select
    local.set $3
+   current_memory
+   local.set $4
    local.get $3
-   grow_memory
-   i32.const 0
-   i32.lt_s
+   local.get $4
+   i32.const 16
+   i32.shl
+   i32.gt_u
    if
+    local.get $3
     local.get $2
+    i32.sub
+    i32.const 65535
+    i32.add
+    i32.const 65535
+    i32.const -1
+    i32.xor
+    i32.and
+    i32.const 16
+    i32.shr_u
+    local.set $5
+    local.get $4
+    local.tee $6
+    local.get $5
+    local.tee $7
+    local.get $6
+    local.get $7
+    i32.gt_s
+    select
+    local.set $6
+    local.get $6
     grow_memory
     i32.const 0
     i32.lt_s
     if
-     unreachable
+     local.get $5
+     grow_memory
+     i32.const 0
+     i32.lt_s
+     if
+      unreachable
+     end
     end
    end
+   local.get $3
+   global.set $~lib/allocator/arena/offset
+   local.get $2
   end
-  local.get $4
-  global.set $~lib/allocator/arena/offset
-  local.get $1
- )
- (func $~lib/memory/memory.allocate (; 7 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
-  local.get $0
-  call $~lib/allocator/arena/__memory_allocate
   return
  )
- (func $assembly/index/NBodySystem#constructor (; 8 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
+ (func $~lib/runtime/doAllocate (; 5 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+  (local $1 i32)
+  local.get $0
+  call $~lib/runtime/ADJUSTOBLOCK
+  call $~lib/memory/memory.allocate
+  local.set $1
+  local.get $1
+  global.get $~lib/runtime/HEADER_MAGIC
+  i32.store
+  local.get $1
+  local.get $0
+  i32.store offset=4
+  local.get $1
+  global.get $~lib/runtime/HEADER_SIZE
+  i32.add
+ )
+ (func $~lib/runtime/ALLOCATE (; 6 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+  local.get $0
+  call $~lib/runtime/doAllocate
+ )
+ (func $~lib/runtime/assertUnregistered (; 7 ;) (type $FUNCSIG$vi) (param $0 i32)
+  local.get $0
+  global.get $~lib/memory/HEAP_BASE
+  i32.gt_u
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 16
+   i32.const 192
+   i32.const 2
+   call $~lib/env/abort
+   unreachable
+  end
+  local.get $0
+  global.get $~lib/runtime/HEADER_SIZE
+  i32.sub
+  i32.load
+  global.get $~lib/runtime/HEADER_MAGIC
+  i32.eq
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 16
+   i32.const 193
+   i32.const 2
+   call $~lib/env/abort
+   unreachable
+  end
+ )
+ (func $~lib/runtime/doRegister (; 8 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
+  local.get $0
+  call $~lib/runtime/assertUnregistered
+  local.get $0
+  global.get $~lib/runtime/HEADER_SIZE
+  i32.sub
+  local.get $1
+  i32.store
+  local.get $0
+ )
+ (func $assembly/index/NBodySystem#constructor (; 9 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
   (local $2 f64)
   (local $3 f64)
   (local $4 f64)
@@ -218,26 +232,26 @@
   local.set $3
   f64.const 0
   local.set $4
-  block $~lib/array/Array<Body>#get:length|inlined.0 (result i32)
-   local.get $1
-   local.set $5
-   local.get $5
-   i32.load offset=4
-  end
-  local.set $6
+  local.get $1
+  call $~lib/array/Array<Body>#get:length
+  local.set $5
   block $break|0
    i32.const 0
-   local.set $5
+   local.set $6
    loop $repeat|0
-    local.get $5
     local.get $6
+    local.get $5
     i32.lt_s
     i32.eqz
     br_if $break|0
     block
      local.get $1
-     local.get $5
-     call $~lib/array/Array<Body>#__unchecked_get
+     i32.load offset=4
+     local.get $6
+     i32.const 2
+     i32.shl
+     i32.add
+     i32.load
      local.set $7
      local.get $7
      f64.load offset=48
@@ -264,18 +278,18 @@
      f64.add
      local.set $4
     end
-    local.get $5
+    local.get $6
     i32.const 1
     i32.add
-    local.set $5
+    local.set $6
     br $repeat|0
     unreachable
    end
    unreachable
   end
   local.get $1
-  i32.const 0
-  call $~lib/array/Array<Body>#__get
+  i32.load offset=4
+  i32.load
   local.get $2
   local.get $3
   local.get $4
@@ -284,8 +298,14 @@
   local.get $0
   i32.eqz
   if
-   i32.const 4
-   call $~lib/memory/memory.allocate
+   block $~lib/runtime/REGISTER<NBodySystem>|inlined.0 (result i32)
+    i32.const 4
+    call $~lib/runtime/ALLOCATE
+    local.set $6
+    local.get $6
+    i32.const 1
+    call $~lib/runtime/doRegister
+   end
    local.set $0
   end
   local.get $0
@@ -293,12 +313,19 @@
   i32.store
   local.get $0
  )
- (func $assembly/index/Body#constructor (; 9 ;) (type $FUNCSIG$iiddddddd) (param $0 i32) (param $1 f64) (param $2 f64) (param $3 f64) (param $4 f64) (param $5 f64) (param $6 f64) (param $7 f64) (result i32)
+ (func $assembly/index/Body#constructor (; 10 ;) (type $FUNCSIG$iiddddddd) (param $0 i32) (param $1 f64) (param $2 f64) (param $3 f64) (param $4 f64) (param $5 f64) (param $6 f64) (param $7 f64) (result i32)
+  (local $8 i32)
   local.get $0
   i32.eqz
   if
-   i32.const 56
-   call $~lib/memory/memory.allocate
+   block $~lib/runtime/REGISTER<Body>|inlined.0 (result i32)
+    i32.const 56
+    call $~lib/runtime/ALLOCATE
+    local.set $8
+    local.get $8
+    i32.const 3
+    call $~lib/runtime/doRegister
+   end
    local.set $0
   end
   local.get $0
@@ -324,7 +351,7 @@
   f64.store offset=48
   local.get $0
  )
- (func $assembly/index/Sun (; 10 ;) (type $FUNCSIG$i) (result i32)
+ (func $assembly/index/Sun (; 11 ;) (type $FUNCSIG$i) (result i32)
   i32.const 0
   f64.const 0
   f64.const 0
@@ -335,7 +362,379 @@
   global.get $assembly/index/SOLAR_MASS
   call $assembly/index/Body#constructor
  )
- (func $assembly/index/Jupiter (; 11 ;) (type $FUNCSIG$i) (result i32)
+ (func $~lib/memory/memory.fill (; 12 ;) (type $FUNCSIG$viii) (param $0 i32) (param $1 i32) (param $2 i32)
+  (local $3 i32)
+  (local $4 i32)
+  (local $5 i64)
+  block $~lib/util/memory/memset|inlined.0
+   local.get $2
+   i32.eqz
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   local.get $0
+   local.get $1
+   i32.store8
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 1
+   i32.sub
+   local.get $1
+   i32.store8
+   local.get $2
+   i32.const 2
+   i32.le_u
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   local.get $0
+   i32.const 1
+   i32.add
+   local.get $1
+   i32.store8
+   local.get $0
+   i32.const 2
+   i32.add
+   local.get $1
+   i32.store8
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 2
+   i32.sub
+   local.get $1
+   i32.store8
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 3
+   i32.sub
+   local.get $1
+   i32.store8
+   local.get $2
+   i32.const 6
+   i32.le_u
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   local.get $0
+   i32.const 3
+   i32.add
+   local.get $1
+   i32.store8
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 4
+   i32.sub
+   local.get $1
+   i32.store8
+   local.get $2
+   i32.const 8
+   i32.le_u
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   i32.const 0
+   local.get $0
+   i32.sub
+   i32.const 3
+   i32.and
+   local.set $3
+   local.get $0
+   local.get $3
+   i32.add
+   local.set $0
+   local.get $2
+   local.get $3
+   i32.sub
+   local.set $2
+   local.get $2
+   i32.const -4
+   i32.and
+   local.set $2
+   i32.const -1
+   i32.const 255
+   i32.div_u
+   local.get $1
+   i32.const 255
+   i32.and
+   i32.mul
+   local.set $4
+   local.get $0
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 4
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $2
+   i32.const 8
+   i32.le_u
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   local.get $0
+   i32.const 4
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   i32.const 8
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 12
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 8
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $2
+   i32.const 24
+   i32.le_u
+   if
+    br $~lib/util/memory/memset|inlined.0
+   end
+   local.get $0
+   i32.const 12
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   i32.const 16
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   i32.const 20
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   i32.const 24
+   i32.add
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 28
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 24
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 20
+   i32.sub
+   local.get $4
+   i32.store
+   local.get $0
+   local.get $2
+   i32.add
+   i32.const 16
+   i32.sub
+   local.get $4
+   i32.store
+   i32.const 24
+   local.get $0
+   i32.const 4
+   i32.and
+   i32.add
+   local.set $3
+   local.get $0
+   local.get $3
+   i32.add
+   local.set $0
+   local.get $2
+   local.get $3
+   i32.sub
+   local.set $2
+   local.get $4
+   i64.extend_i32_u
+   local.get $4
+   i64.extend_i32_u
+   i64.const 32
+   i64.shl
+   i64.or
+   local.set $5
+   block $break|0
+    loop $continue|0
+     local.get $2
+     i32.const 32
+     i32.ge_u
+     if
+      block
+       local.get $0
+       local.get $5
+       i64.store
+       local.get $0
+       i32.const 8
+       i32.add
+       local.get $5
+       i64.store
+       local.get $0
+       i32.const 16
+       i32.add
+       local.get $5
+       i64.store
+       local.get $0
+       i32.const 24
+       i32.add
+       local.get $5
+       i64.store
+       local.get $2
+       i32.const 32
+       i32.sub
+       local.set $2
+       local.get $0
+       i32.const 32
+       i32.add
+       local.set $0
+      end
+      br $continue|0
+     end
+    end
+   end
+  end
+ )
+ (func $~lib/arraybuffer/ArrayBuffer#constructor (; 13 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
+  (local $2 i32)
+  (local $3 i32)
+  local.get $1
+  global.get $~lib/runtime/MAX_BYTELENGTH
+  i32.gt_u
+  if
+   i32.const 0
+   i32.const 56
+   i32.const 24
+   i32.const 43
+   call $~lib/env/abort
+   unreachable
+  end
+  block $~lib/runtime/ALLOCATE|inlined.0 (result i32)
+   local.get $1
+   local.set $2
+   local.get $2
+   call $~lib/runtime/doAllocate
+  end
+  local.set $3
+  local.get $3
+  i32.const 0
+  local.get $1
+  call $~lib/memory/memory.fill
+  block $~lib/runtime/REGISTER<ArrayBuffer>|inlined.0 (result i32)
+   local.get $3
+   local.set $2
+   local.get $2
+   i32.const 4
+   call $~lib/runtime/doRegister
+  end
+ )
+ (func $~lib/runtime/ArrayBufferView#constructor (; 14 ;) (type $FUNCSIG$iiii) (param $0 i32) (param $1 i32) (param $2 i32) (result i32)
+  (local $3 i32)
+  (local $4 i32)
+  local.get $1
+  global.get $~lib/runtime/MAX_BYTELENGTH
+  local.get $2
+  i32.shr_u
+  i32.gt_u
+  if
+   i32.const 0
+   i32.const 16
+   i32.const 227
+   i32.const 57
+   call $~lib/env/abort
+   unreachable
+  end
+  i32.const 0
+  local.get $1
+  local.get $2
+  i32.shl
+  local.tee $1
+  call $~lib/arraybuffer/ArrayBuffer#constructor
+  local.set $3
+  block (result i32)
+   local.get $0
+   i32.eqz
+   if
+    block $~lib/runtime/REGISTER<ArrayBufferView>|inlined.0 (result i32)
+     i32.const 12
+     call $~lib/runtime/ALLOCATE
+     local.set $4
+     local.get $4
+     i32.const 5
+     call $~lib/runtime/doRegister
+    end
+    local.set $0
+   end
+   local.get $0
+   i32.const 0
+   i32.store
+   local.get $0
+   i32.const 0
+   i32.store offset=4
+   local.get $0
+   i32.const 0
+   i32.store offset=8
+   local.get $0
+  end
+  local.get $3
+  i32.store
+  local.get $0
+  local.get $3
+  i32.store offset=4
+  local.get $0
+  local.get $1
+  i32.store offset=8
+  local.get $0
+ )
+ (func $~lib/array/Array<Body>#constructor (; 15 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
+  (local $2 i32)
+  local.get $0
+  if (result i32)
+   local.get $0
+  else   
+   i32.const 16
+   call $~lib/runtime/ALLOCATE
+   local.set $2
+   local.get $2
+   i32.const 6
+   call $~lib/runtime/doRegister
+  end
+  local.get $1
+  i32.const 2
+  call $~lib/runtime/ArrayBufferView#constructor
+  local.set $0
+  local.get $0
+  i32.const 0
+  i32.store offset=12
+  local.get $0
+  local.get $1
+  i32.store offset=12
+  local.get $0
+ )
+ (func $assembly/index/Jupiter (; 16 ;) (type $FUNCSIG$i) (result i32)
   i32.const 0
   f64.const 4.841431442464721
   f64.const -1.1603200440274284
@@ -354,7 +753,7 @@
   f64.mul
   call $assembly/index/Body#constructor
  )
- (func $assembly/index/Saturn (; 12 ;) (type $FUNCSIG$i) (result i32)
+ (func $assembly/index/Saturn (; 17 ;) (type $FUNCSIG$i) (result i32)
   i32.const 0
   f64.const 8.34336671824458
   f64.const 4.124798564124305
@@ -373,7 +772,7 @@
   f64.mul
   call $assembly/index/Body#constructor
  )
- (func $assembly/index/Uranus (; 13 ;) (type $FUNCSIG$i) (result i32)
+ (func $assembly/index/Uranus (; 18 ;) (type $FUNCSIG$i) (result i32)
   i32.const 0
   f64.const 12.894369562139131
   f64.const -15.111151401698631
@@ -392,7 +791,7 @@
   f64.mul
   call $assembly/index/Body#constructor
  )
- (func $assembly/index/Neptune (; 14 ;) (type $FUNCSIG$i) (result i32)
+ (func $assembly/index/Neptune (; 19 ;) (type $FUNCSIG$i) (result i32)
   i32.const 0
   f64.const 15.379697114850917
   f64.const -25.919314609987964
@@ -411,388 +810,9 @@
   f64.mul
   call $assembly/index/Body#constructor
  )
- (func $~lib/internal/arraybuffer/computeSize (; 15 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
-  i32.const 1
-  i32.const 32
-  local.get $0
-  i32.const 8
-  i32.add
-  i32.const 1
-  i32.sub
-  i32.clz
-  i32.sub
-  i32.shl
- )
- (func $~lib/internal/arraybuffer/allocateUnsafe (; 16 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
-  (local $1 i32)
-  (local $2 i32)
-  local.get $0
-  i32.const 1073741816
-  i32.le_u
-  i32.eqz
-  if
-   i32.const 0
-   i32.const 40
-   i32.const 26
-   i32.const 2
-   call $~lib/env/abort
-   unreachable
-  end
-  block $~lib/memory/memory.allocate|inlined.0 (result i32)
-   local.get $0
-   call $~lib/internal/arraybuffer/computeSize
-   local.set $2
-   local.get $2
-   call $~lib/allocator/arena/__memory_allocate
-   br $~lib/memory/memory.allocate|inlined.0
-  end
-  local.set $1
-  local.get $1
-  local.get $0
-  i32.store
-  local.get $1
- )
- (func $~lib/internal/memory/memset (; 17 ;) (type $FUNCSIG$viii) (param $0 i32) (param $1 i32) (param $2 i32)
-  (local $3 i32)
-  (local $4 i32)
-  (local $5 i64)
-  local.get $2
-  i32.eqz
-  if
-   return
-  end
-  local.get $0
-  local.get $1
-  i32.store8
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 1
-  i32.sub
-  local.get $1
-  i32.store8
-  local.get $2
-  i32.const 2
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 1
-  i32.add
-  local.get $1
-  i32.store8
-  local.get $0
-  i32.const 2
-  i32.add
-  local.get $1
-  i32.store8
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 2
-  i32.sub
-  local.get $1
-  i32.store8
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 3
-  i32.sub
-  local.get $1
-  i32.store8
-  local.get $2
-  i32.const 6
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 3
-  i32.add
-  local.get $1
-  i32.store8
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 4
-  i32.sub
-  local.get $1
-  i32.store8
-  local.get $2
-  i32.const 8
-  i32.le_u
-  if
-   return
-  end
-  i32.const 0
-  local.get $0
-  i32.sub
-  i32.const 3
-  i32.and
-  local.set $3
-  local.get $0
-  local.get $3
-  i32.add
-  local.set $0
-  local.get $2
-  local.get $3
-  i32.sub
-  local.set $2
-  local.get $2
-  i32.const -4
-  i32.and
-  local.set $2
-  i32.const -1
-  i32.const 255
-  i32.div_u
-  local.get $1
-  i32.const 255
-  i32.and
-  i32.mul
-  local.set $4
-  local.get $0
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 4
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $2
-  i32.const 8
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 4
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  i32.const 8
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 12
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 8
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $2
-  i32.const 24
-  i32.le_u
-  if
-   return
-  end
-  local.get $0
-  i32.const 12
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  i32.const 16
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  i32.const 20
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  i32.const 24
-  i32.add
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 28
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 24
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 20
-  i32.sub
-  local.get $4
-  i32.store
-  local.get $0
-  local.get $2
-  i32.add
-  i32.const 16
-  i32.sub
-  local.get $4
-  i32.store
-  i32.const 24
-  local.get $0
-  i32.const 4
-  i32.and
-  i32.add
-  local.set $3
-  local.get $0
-  local.get $3
-  i32.add
-  local.set $0
-  local.get $2
-  local.get $3
-  i32.sub
-  local.set $2
-  local.get $4
-  i64.extend_i32_u
-  local.get $4
-  i64.extend_i32_u
-  i64.const 32
-  i64.shl
-  i64.or
-  local.set $5
-  block $break|0
-   loop $continue|0
-    local.get $2
-    i32.const 32
-    i32.ge_u
-    if
-     block
-      local.get $0
-      local.get $5
-      i64.store
-      local.get $0
-      i32.const 8
-      i32.add
-      local.get $5
-      i64.store
-      local.get $0
-      i32.const 16
-      i32.add
-      local.get $5
-      i64.store
-      local.get $0
-      i32.const 24
-      i32.add
-      local.get $5
-      i64.store
-      local.get $2
-      i32.const 32
-      i32.sub
-      local.set $2
-      local.get $0
-      i32.const 32
-      i32.add
-      local.set $0
-     end
-     br $continue|0
-    end
-   end
-  end
- )
- (func $~lib/array/Array<Body>#constructor (; 18 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
-  (local $2 i32)
-  (local $3 i32)
-  (local $4 i32)
-  (local $5 i32)
-  (local $6 i32)
-  local.get $1
-  i32.const 268435454
-  i32.gt_u
-  if
-   i32.const 0
-   i32.const 8
-   i32.const 45
-   i32.const 39
-   call $~lib/env/abort
-   unreachable
-  end
-  local.get $1
-  i32.const 2
-  i32.shl
-  local.set $2
-  local.get $2
-  call $~lib/internal/arraybuffer/allocateUnsafe
-  local.set $3
-  block (result i32)
-   local.get $0
-   i32.eqz
-   if
-    i32.const 8
-    call $~lib/memory/memory.allocate
-    local.set $0
-   end
-   local.get $0
-   i32.const 0
-   i32.store
-   local.get $0
-   i32.const 0
-   i32.store offset=4
-   local.get $0
-  end
-  local.get $3
-  i32.store
-  local.get $0
-  local.get $1
-  i32.store offset=4
-  block $~lib/memory/memory.fill|inlined.0
-   local.get $3
-   i32.const 8
-   i32.add
-   local.set $4
-   i32.const 0
-   local.set $5
-   local.get $2
-   local.set $6
-   local.get $4
-   local.get $5
-   local.get $6
-   call $~lib/internal/memory/memset
-  end
-  local.get $0
- )
- (func $~lib/array/Array<Body>#__unchecked_set (; 19 ;) (type $FUNCSIG$viii) (param $0 i32) (param $1 i32) (param $2 i32)
-  (local $3 i32)
-  (local $4 i32)
-  (local $5 i32)
-  (local $6 i32)
-  local.get $0
-  i32.load
-  local.set $3
-  local.get $1
-  local.set $4
-  local.get $2
-  local.set $5
-  i32.const 0
-  local.set $6
-  local.get $3
-  local.get $4
-  i32.const 2
-  i32.shl
-  i32.add
-  local.get $6
-  i32.add
-  local.get $5
-  i32.store offset=8
- )
  (func $assembly/index/init (; 20 ;) (type $FUNCSIG$v)
   (local $0 i32)
+  (local $1 i32)
   i32.const 0
   block (result i32)
    i32.const 0
@@ -800,25 +820,23 @@
    call $~lib/array/Array<Body>#constructor
    local.set $0
    local.get $0
-   i32.const 0
+   i32.load offset=4
+   local.set $1
+   local.get $1
    call $assembly/index/Sun
-   call $~lib/array/Array<Body>#__unchecked_set
-   local.get $0
-   i32.const 1
+   i32.store
+   local.get $1
    call $assembly/index/Jupiter
-   call $~lib/array/Array<Body>#__unchecked_set
-   local.get $0
-   i32.const 2
+   i32.store offset=4
+   local.get $1
    call $assembly/index/Saturn
-   call $~lib/array/Array<Body>#__unchecked_set
-   local.get $0
-   i32.const 3
+   i32.store offset=8
+   local.get $1
    call $assembly/index/Uranus
-   call $~lib/array/Array<Body>#__unchecked_set
-   local.get $0
-   i32.const 4
+   i32.store offset=12
+   local.get $1
    call $assembly/index/Neptune
-   call $~lib/array/Array<Body>#__unchecked_set
+   i32.store offset=16
    local.get $0
   end
   call $assembly/index/NBodySystem#constructor
@@ -849,26 +867,26 @@
   local.get $0
   i32.load
   local.set $2
-  block $~lib/array/Array<Body>#get:length|inlined.1 (result i32)
-   local.get $2
-   local.set $3
-   local.get $3
-   i32.load offset=4
-  end
-  local.set $4
+  local.get $2
+  call $~lib/array/Array<Body>#get:length
+  local.set $3
   block $break|0
    i32.const 0
-   local.set $3
+   local.set $4
    loop $repeat|0
-    local.get $3
     local.get $4
+    local.get $3
     i32.lt_u
     i32.eqz
     br_if $break|0
     block
      local.get $2
-     local.get $3
-     call $~lib/array/Array<Body>#__unchecked_get
+     i32.load offset=4
+     local.get $4
+     i32.const 2
+     i32.shl
+     i32.add
+     i32.load
      local.set $5
      local.get $5
      f64.load
@@ -892,20 +910,24 @@
      f64.load offset=48
      local.set $12
      block $break|1
-      local.get $3
+      local.get $4
       i32.const 1
       i32.add
       local.set $13
       loop $repeat|1
        local.get $13
-       local.get $4
+       local.get $3
        i32.lt_u
        i32.eqz
        br_if $break|1
        block
         local.get $2
+        i32.load offset=4
         local.get $13
-        call $~lib/array/Array<Body>#__unchecked_get
+        i32.const 2
+        i32.shl
+        i32.add
+        i32.load
         local.set $14
         local.get $6
         local.get $14
@@ -1042,10 +1064,10 @@
      f64.add
      f64.store offset=16
     end
-    local.get $3
+    local.get $4
     i32.const 1
     i32.add
-    local.set $3
+    local.set $4
     br $repeat|0
     unreachable
    end
@@ -1080,12 +1102,8 @@
    block
     i32.const 0
     local.set $3
-    block $~lib/array/Array<Body>#get:length|inlined.2 (result i32)
-     local.get $2
-     local.set $4
-     local.get $4
-     i32.load offset=4
-    end
+    local.get $2
+    call $~lib/array/Array<Body>#get:length
     local.set $4
    end
    loop $repeat|0
@@ -1096,8 +1114,12 @@
     br_if $break|0
     block
      local.get $2
+     i32.load offset=4
      local.get $3
-     call $~lib/array/Array<Body>#__unchecked_get
+     i32.const 2
+     i32.shl
+     i32.add
+     i32.load
      local.set $5
      local.get $5
      f64.load
@@ -1151,8 +1173,12 @@
        br_if $break|1
        block
         local.get $2
+        i32.load offset=4
         local.get $13
-        call $~lib/array/Array<Body>#__unchecked_get
+        i32.const 2
+        i32.shl
+        i32.add
+        i32.load
         local.set $14
         local.get $6
         local.get $14
@@ -1250,28 +1276,36 @@
  )
  (func $assembly/index/getBody (; 25 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
-  (local $2 i32)
   global.get $assembly/index/system
   i32.load
   local.set $1
   local.get $0
-  block $~lib/array/Array<Body>#get:length|inlined.4 (result i32)
-   local.get $1
-   local.set $2
-   local.get $2
-   i32.load offset=4
-  end
+  local.get $1
+  call $~lib/array/Array<Body>#get:length
   i32.lt_u
   if (result i32)
    local.get $1
+   i32.load offset=4
    local.get $0
-   call $~lib/array/Array<Body>#__get
+   i32.const 2
+   i32.shl
+   i32.add
+   i32.load
   else   
    i32.const 0
   end
  )
  (func $start (; 26 ;) (type $FUNCSIG$v)
-  call $start:assembly/index
+  global.get $~lib/memory/HEAP_BASE
+  i32.const 7
+  i32.add
+  i32.const 7
+  i32.const -1
+  i32.xor
+  i32.and
+  global.set $~lib/allocator/arena/startOffset
+  global.get $~lib/allocator/arena/startOffset
+  global.set $~lib/allocator/arena/offset
  )
  (func $null (; 27 ;) (type $FUNCSIG$v)
  )
diff --git a/src/resolver.ts b/src/resolver.ts
index 0c3fa35b..e057fbcc 100644
--- a/src/resolver.ts
+++ b/src/resolver.ts
@@ -82,6 +82,10 @@ import {
   Token
 } from "./tokenizer";
 
+import {
+  BuiltinSymbols
+} from "./builtins";
+
 /** Indicates whether errors are reported or not. */
 export enum ReportMode {
   /** Report errors. */
@@ -1208,6 +1212,14 @@ export class Resolver extends DiagnosticEmitter {
     );
     if (!target) return null;
     if (target.kind == ElementKind.FUNCTION_PROTOTYPE) {
+      // `unchecked(expr: *): *` is special
+      if (
+        (<FunctionPrototype>target).internalName == BuiltinSymbols.unchecked &&
+        expression.arguments.length > 0
+      ) {
+        return this.resolveExpression(expression.arguments[0], flow, contextualType, reportMode);
+      }
+      // otherwise resolve normally
       let instance = this.resolveFunctionInclTypeArguments(
         <FunctionPrototype>target,
         expression.typeArguments,