asm2wasm atomics (#1171)

* translate asm.js atomics into wasm atomics

* fix wasm-builder atomic load emitting, the alignment is the loaded size, not the output size

* don't require code for each node type in vaccuum, for non-mentioned nodes, assume we can't optimize them out

* support atomics in hashing, comparing, and copying

1 files changed, 69 insertions, 0 deletions

diff --git a/test/threads.fromasm b/test/threads.fromasm
new file mode 100644
index 000000000..5114d985a
--- /dev/null
+++ b/test/threads.fromasm
@@ -0,0 +1,69 @@
+(module
+ (import "env" "memory" (memory $0 256 256 shared))
+ (import "env" "table" (table 0 0 anyfunc))
+ (import "env" "memoryBase" (global $memoryBase i32))
+ (import "env" "tableBase" (global $tableBase i32))
+ (data (get_global $memoryBase) "threads.asm.js")
+ (export "test" (func $test))
+ (func $test
+  (local $0 i32)
+  (drop
+   (i32.atomic.load
+    (i32.const 4916)
+   )
+  )
+  (drop
+   (i32.atomic.rmw.xor
+    (i32.atomic.rmw.or
+     (i32.atomic.rmw.and
+      (i32.atomic.rmw.sub
+       (i32.atomic.rmw.add
+        (i32.atomic.rmw.cmpxchg
+         (block (result i32)
+          (i32.atomic.store
+           (i32.atomic.load16_u
+            (i32.const 2458)
+           )
+           (tee_local $0
+            (i32.const 0)
+           )
+          )
+          (i32.atomic.rmw.xchg
+           (get_local $0)
+           (i32.const 1)
+          )
+         )
+         (i32.const 1)
+         (i32.const 2)
+        )
+        (i32.const 0)
+       )
+       (i32.const 0)
+      )
+      (i32.const 0)
+     )
+     (i32.const 0)
+    )
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.atomic.rmw.xor
+    (i32.const 4096)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.atomic.rmw16_u.xor
+    (i32.const 2048)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.atomic.rmw8_u.xor
+    (i32.const 1024)
+    (i32.const 0)
+   )
+  )
+ )
+)