Add memory allocation

Author: dontru

src/memory_allocation.wat

@@ -0,0 +1,81 @@
+(module
+  (import "env" "_Znwj" (func $_Znwj (param i32) (result i32))) ;; new
+  (import "env" "_Znaj" (func $_Znaj (param i32) (result i32))) ;; new[]
+  (import "env" "_ZdlPv" (func $_ZdlPv (param i32))) ;; delete
+  (import "env" "_ZdaPv" (func $_ZdaPv (param i32))) ;; delete[]
+
+  (memory $memory 1)
+
+  ;; int load(int* a) {
+  ;;   return *a;
+  ;; }
+  (func $load (param $a i32) (result i32)
+    (i32.load
+      (get_local $a)))
+
+  ;; void store(int* a, int b) {
+  ;;   *a = b;
+  ;; }
+  (func $store (param $a i32) (param $b i32)
+    (i32.store
+      (get_local $a)
+      (get_local $b)))
+
+  ;; int* func1() {
+  ;;   int* ptr = new int;
+  ;;   return ptr;
+  ;; }
+  (func $func1 (result i32)
+    (call $_Znwj
+      (i32.const 4)))
+
+  ;; void func2(int* ptr) {
+  ;;   delete ptr;
+  ;; }
+  (func $func2 (param $ptr i32)
+    (block $B0
+      (br_if $B0
+        (i32.eqz
+          (get_local $ptr)))
+      (call $_ZdlPv
+        (get_local $ptr))))
+
+  ;; int* func3() {
+  ;;   int* ptr = new int[10];
+  ;;   return ptr;
+  ;; }
+  (func $func3 (result i32)
+    (call $_Znaj
+      (i32.const 40)))
+
+  ;; void func4(int* ptr) {
+  ;;   delete[] ptr;
+  ;; }
+  (func $func4 (param $ptr i32)
+    (block $B0
+      (br_if $B0
+        (i32.eqz
+          (get_local $ptr)))
+      (call $_ZdaPv
+        (get_local $ptr))))
+
+  ;; int* func5(int size) {
+  ;;   int* ptr = new int[size];
+  ;;   return ptr;
+  ;; }
+  (func $func5 (param $size i32) (result i32)
+    (local $l0 i64)
+    (call $_Znaj
+      (select
+        (i32.const -1)
+        (i32.wrap/i64
+          (tee_local $l0
+            (i64.shl
+              (i64.extend_u/i32
+                (get_local $size))
+              (i64.const 2))))
+        (i32.wrap/i64
+          (i64.shr_u
+            (get_local $l0)
+            (i64.const 32))))))
+)