bh_atomic.h: Add BH_ATOMIC_32_FETCH_ADD/BH_ATOMIC_32_FETCH_SUB (#2408)

core/shared/utils/bh_atomic.h

@@ -63,10 +63,16 @@ typedef uint32 bh_atomic_32_t;
     __atomic_fetch_or(&(v), (val), __ATOMIC_SEQ_CST)
 #define BH_ATOMIC_32_FETCH_AND(v, val) \
     __atomic_fetch_and(&(v), (val), __ATOMIC_SEQ_CST)
+#define BH_ATOMIC_32_FETCH_ADD(v, val) \
+    __atomic_fetch_add(&(v), (val), __ATOMIC_SEQ_CST)
+#define BH_ATOMIC_32_FETCH_SUB(v, val) \
+    __atomic_fetch_sub(&(v), (val), __ATOMIC_SEQ_CST)
 #else /* else of defined(CLANG_GCC_HAS_ATOMIC_BUILTIN) */
 #define BH_ATOMIC_32_LOAD(v) (v)
 #define BH_ATOMIC_32_FETCH_OR(v, val) nonatomic_32_fetch_or(&(v), val)
 #define BH_ATOMIC_32_FETCH_AND(v, val) nonatomic_32_fetch_and(&(v), val)
+#define BH_ATOMIC_32_FETCH_ADD(v, val) nonatomic_32_fetch_add(&(v), val)
+#define BH_ATOMIC_32_FETCH_SUB(v, val) nonatomic_32_fetch_sub(&(v), val)
 
 static inline uint32
 nonatomic_32_fetch_or(bh_atomic_32_t *p, uint32 val)
@@ -84,6 +90,22 @@ nonatomic_32_fetch_and(bh_atomic_32_t *p, uint32 val)
     return old;
 }
 
+static inline uint32
+nonatomic_32_fetch_add(bh_atomic_32_t *p, uint32 val)
+{
+    uint32 old = *p;
+    *p += val;
+    return old;
+}
+
+static inline uint32
+nonatomic_32_fetch_sub(bh_atomic_32_t *p, uint32 val)
+{
+    uint32 old = *p;
+    *p -= val;
+    return old;
+}
+
 /* The flag can be defined by the user if the platform
    supports atomic access to uint32 aligned memory. */
 #ifdef WASM_UINT32_IS_ATOMIC

samples/bh_atomic/main.c

@@ -28,5 +28,15 @@ main(int argc, char **argv)
     assert(o == 0x00ff00ff);
     assert(v == 0x00ff0000);
 
+    v = 0x00ff00ff;
+    o = BH_ATOMIC_32_FETCH_ADD(v, 0x10101);
+    assert(o == 0x00ff00ff);
+    assert(v == 0x00ff00ff + 0x10101);
+
+    v = 0x00ff00ff;
+    o = BH_ATOMIC_32_FETCH_SUB(v, 0x10101);
+    assert(o == 0x00ff00ff);
+    assert(v == 0x00ff00ff - 0x10101);
+
     return 0;
 }