Avoid new blocks in binary reading/writing (#1165)

* don't emit a toplevel block if we don't need to, as in wasm it is a list context

* don't create unnecessary blocks in wasm reading

1 files changed, 164 insertions, 210 deletions

diff --git a/test/unit.wast.fromBinary b/test/unit.wast.fromBinary
index 817cc3c7a..f4e9f88b9 100644
--- a/test/unit.wast.fromBinary
+++ b/test/unit.wast.fromBinary
@@ -19,27 +19,25 @@
  (export "big_negative" (func $big_negative))
  (func $big_negative (type $1)
   (local $var$0 f64)
-  (block $label$0
-   (set_local $var$0
-    (f64.const -2147483648)
-   )
-   (set_local $var$0
-    (f64.const -2147483648)
-   )
-   (set_local $var$0
-    (f64.const -21474836480)
-   )
-   (set_local $var$0
-    (f64.const 0.039625)
-   )
-   (set_local $var$0
-    (f64.const -0.039625)
-   )
+  (set_local $var$0
+   (f64.const -2147483648)
+  )
+  (set_local $var$0
+   (f64.const -2147483648)
+  )
+  (set_local $var$0
+   (f64.const -21474836480)
+  )
+  (set_local $var$0
+   (f64.const 0.039625)
+  )
+  (set_local $var$0
+   (f64.const -0.039625)
   )
  )
  (func $importedDoubles (type $4) (result f64)
   (local $var$0 f64)
-  (block $label$0 (result f64)
+  (block $label$1 (result f64)
    (set_local $var$0
     (f64.add
      (f64.add
@@ -71,10 +69,8 @@
      )
      (i32.const 0)
     )
-    (block $label$1
-     (br $label$0
-      (f64.const -3.4)
-     )
+    (br $label$1
+     (f64.const -3.4)
     )
    )
    (if
@@ -84,10 +80,8 @@
      )
      (f64.const 0)
     )
-    (block $label$2
-     (br $label$0
-      (f64.const 5.6)
-     )
+    (br $label$1
+     (f64.const 5.6)
     )
    )
    (f64.const 1.2)
@@ -97,16 +91,14 @@
   (local $var$2 i32)
   (local $var$3 f64)
   (local $var$4 f64)
-  (block $label$0 (result f64)
+  (block $label$1 (result f64)
    (if
     (f64.gt
      (get_local $var$0)
      (f64.const 0)
     )
-    (block $label$1
-     (br $label$0
-      (f64.const 1.2)
-     )
+    (br $label$1
+     (f64.const 1.2)
     )
    )
    (if
@@ -114,10 +106,8 @@
      (get_local $var$4)
      (f64.const 0)
     )
-    (block $label$2
-     (br $label$0
-      (f64.const -3.4)
-     )
+    (br $label$1
+     (f64.const -3.4)
     )
    )
    (if
@@ -125,10 +115,8 @@
      (get_local $var$2)
      (i32.const 0)
     )
-    (block $label$3
-     (br $label$0
-      (f64.const 5.6)
-     )
+    (br $label$1
+     (f64.const 5.6)
     )
    )
    (if
@@ -136,10 +124,8 @@
      (get_local $var$0)
      (get_local $var$1)
     )
-    (block $label$4
-     (br $label$0
-      (get_local $var$0)
-     )
+    (br $label$1
+     (get_local $var$0)
     )
    )
    (get_local $var$1)
@@ -166,23 +152,21 @@
  (func $conversions (type $1)
   (local $var$0 i32)
   (local $var$1 f64)
-  (block $label$0
-   (set_local $var$0
-    (call $import$1
-     (get_local $var$1)
-    )
+  (set_local $var$0
+   (call $import$1
+    (get_local $var$1)
    )
-   (set_local $var$1
-    (f64.convert_s/i32
-     (get_local $var$0)
-    )
+  )
+  (set_local $var$1
+   (f64.convert_s/i32
+    (get_local $var$0)
    )
-   (set_local $var$1
-    (f64.convert_u/i32
-     (i32.shr_u
-      (get_local $var$0)
-      (i32.const 0)
-     )
+  )
+  (set_local $var$1
+   (f64.convert_u/i32
+    (i32.shr_u
+     (get_local $var$0)
+     (i32.const 0)
     )
    )
   )
@@ -191,13 +175,13 @@
   (local $var$0 f64)
   (set_local $var$0
    (f64.sub
-    (block $label$0 (result f64)
+    (block $label$1 (result f64)
      (drop
       (f64.const 0.1)
      )
      (f64.const 5.1)
     )
-    (block $label$1 (result f64)
+    (block $label$2 (result f64)
      (drop
       (f64.const 3.2)
      )
@@ -207,75 +191,75 @@
   )
  )
  (func $switcher (type $6) (param $var$0 i32) (result i32)
-  (block $label$0 (result i32)
-   (block $label$1
-    (block $label$2
-     (block $label$3
-      (block $label$4
-       (br_table $label$4 $label$3 $label$2
+  (block $label$1 (result i32)
+   (block $label$2
+    (block $label$3
+     (block $label$4
+      (block $label$5
+       (br_table $label$5 $label$4 $label$3
         (i32.sub
          (get_local $var$0)
          (i32.const 1)
         )
        )
       )
-      (br $label$0
+      (br $label$1
        (i32.const 1)
       )
      )
-     (br $label$0
+     (br $label$1
       (i32.const 2)
      )
     )
     (nop)
    )
-   (block $label$5
-    (block $label$6
-     (block $label$7
-      (block $label$8
-       (br_table $label$7 $label$6 $label$6 $label$6 $label$6 $label$6 $label$6 $label$8 $label$6
+   (block $label$6
+    (block $label$7
+     (block $label$8
+      (block $label$9
+       (br_table $label$8 $label$7 $label$7 $label$7 $label$7 $label$7 $label$7 $label$9 $label$7
         (i32.sub
          (get_local $var$0)
          (i32.const 5)
         )
        )
       )
-      (br $label$0
+      (br $label$1
        (i32.const 121)
       )
      )
-     (br $label$0
+     (br $label$1
       (i32.const 51)
      )
     )
     (nop)
    )
-   (block $label$9
-    (block $label$10
-     (block $label$11
-      (block $label$12
-       (block $label$13
-        (block $label$14
-         (br_table $label$11 $label$10 $label$10 $label$12 $label$10 $label$10 $label$10 $label$10 $label$13 $label$10 $label$14 $label$10
+   (block $label$10
+    (block $label$11
+     (block $label$12
+      (block $label$13
+       (block $label$14
+        (block $label$15
+         (br_table $label$12 $label$11 $label$11 $label$13 $label$11 $label$11 $label$11 $label$11 $label$14 $label$11 $label$15 $label$11
           (i32.sub
            (get_local $var$0)
            (i32.const 2)
           )
          )
         )
-        (br $label$9)
+        (br $label$10)
        )
-       (br $label$9)
+       (br $label$10)
       )
-      (block $label$15
-       (loop $label$16
-        (br $label$15)
+      (block $label$16
+       (loop $label$17
+        (br $label$16)
        )
       )
      )
-     (block $label$17
-      (loop $label$18
-       (br $label$9)
+     (block $label$18
+      (loop $label$19
+       (br $label$10)
       )
      )
     )
@@ -285,8 +269,8 @@
   )
  )
  (func $blocker (type $1)
-  (block $label$0
-   (br $label$0)
+  (block $label$1
+   (br $label$1)
   )
  )
  (func $frem (type $4) (result f64)
@@ -297,44 +281,40 @@
  )
  (func $big_uint_div_u (type $5) (result i32)
   (local $var$0 i32)
-  (block $label$0 (result i32)
-   (set_local $var$0
-    (i32.and
-     (i32.div_u
-      (i32.const -1)
-      (i32.const 2)
-     )
+  (set_local $var$0
+   (i32.and
+    (i32.div_u
      (i32.const -1)
+     (i32.const 2)
     )
+    (i32.const -1)
    )
-   (get_local $var$0)
   )
+  (get_local $var$0)
  )
  (func $fr (type $0) (param $var$0 f32)
   (local $var$1 f32)
   (local $var$2 f64)
-  (block $label$0
-   (drop
-    (f32.demote/f64
-     (get_local $var$2)
-    )
-   )
-   (drop
-    (get_local $var$1)
-   )
-   (drop
-    (f32.const 5)
-   )
-   (drop
-    (f32.const 0)
-   )
-   (drop
-    (f32.const 5)
-   )
-   (drop
-    (f32.const 0)
+  (drop
+   (f32.demote/f64
+    (get_local $var$2)
    )
   )
+  (drop
+   (get_local $var$1)
+  )
+  (drop
+   (f32.const 5)
+  )
+  (drop
+   (f32.const 0)
+  )
+  (drop
+   (f32.const 5)
+  )
+  (drop
+   (f32.const 0)
+  )
  )
  (func $negZero (type $4) (result f64)
   (f64.const -0)
@@ -344,54 +324,50 @@
   (local $var$1 i32)
   (local $var$2 f32)
   (local $var$3 f64)
-  (block $label$0
-   (set_local $var$0
-    (block $label$1 (result i32)
-     (set_local $var$1
+  (set_local $var$0
+   (block $label$1 (result i32)
+    (set_local $var$1
+     (i32.const 0)
+    )
+    (select
+     (i32.sub
       (i32.const 0)
+      (get_local $var$1)
      )
-     (select
-      (i32.sub
-       (i32.const 0)
-       (get_local $var$1)
-      )
+     (get_local $var$1)
+     (i32.lt_s
       (get_local $var$1)
-      (i32.lt_s
-       (get_local $var$1)
-       (i32.const 0)
-      )
+      (i32.const 0)
      )
     )
    )
-   (set_local $var$3
-    (f64.abs
-     (f64.const 0)
-    )
+  )
+  (set_local $var$3
+   (f64.abs
+    (f64.const 0)
    )
-   (set_local $var$2
-    (f32.abs
-     (f32.const 0)
-    )
+  )
+  (set_local $var$2
+   (f32.abs
+    (f32.const 0)
    )
   )
  )
  (func $neg (type $1)
   (local $var$0 f32)
-  (block $label$0
-   (set_local $var$0
-    (f32.neg
-     (get_local $var$0)
-    )
-   )
-   (call_indirect $0
+  (set_local $var$0
+   (f32.neg
     (get_local $var$0)
-    (i32.add
-     (i32.and
-      (i32.const 1)
-      (i32.const 7)
-     )
-     (i32.const 8)
+   )
+  )
+  (call_indirect $0
+   (get_local $var$0)
+   (i32.add
+    (i32.and
+     (i32.const 1)
+     (i32.const 7)
     )
+    (i32.const 8)
    )
   )
  )
@@ -426,18 +402,16 @@
   (nop)
  )
  (func $block_and_after (type $5) (result i32)
-  (block $label$0 (result i32)
-   (block $label$1
-    (drop
-     (i32.const 1)
-    )
-    (br $label$1)
+  (block $label$1
+   (drop
+    (i32.const 1)
    )
-   (i32.const 0)
+   (br $label$1)
   )
+  (i32.const 0)
  )
  (func $loop-roundtrip (type $7) (param $var$0 f64) (result f64)
-  (loop $label$0 (result f64)
+  (loop $label$1 (result f64)
    (drop
     (get_local $var$0)
    )
@@ -459,7 +433,7 @@
   )
  )
  (func $unreachable-block (type $5) (result i32)
-  (block $label$0
+  (block $label$1
    (drop
     (i32.const 1)
    )
@@ -469,72 +443,58 @@
   )
  )
  (func $unreachable-block-toplevel (type $5) (result i32)
-  (block $label$0
-   (drop
-    (i32.const 1)
-   )
-   (return
-    (i32.const 2)
-   )
+  (drop
+   (i32.const 1)
+  )
+  (return
+   (i32.const 2)
   )
  )
  (func $unreachable-block0 (type $5) (result i32)
-  (block $label$0
+  (block $label$1
    (return
     (i32.const 2)
    )
   )
  )
  (func $unreachable-block0-toplevel (type $5) (result i32)
-  (block $label$0
-   (return
-    (i32.const 2)
-   )
+  (return
+   (i32.const 2)
   )
  )
  (func $unreachable-block-with-br (type $5) (result i32)
-  (block $label$0 (result i32)
-   (block $label$1
-    (drop
-     (i32.const 1)
-    )
-    (br $label$1)
+  (block $label$1
+   (drop
+    (i32.const 1)
    )
-   (i32.const 1)
+   (br $label$1)
   )
+  (i32.const 1)
  )
  (func $unreachable-if (type $5) (result i32)
   (if
    (i32.const 3)
-   (block $label$0
-    (return
-     (i32.const 2)
-    )
+   (return
+    (i32.const 2)
    )
-   (block $label$1
-    (return
-     (i32.const 1)
-    )
+   (return
+    (i32.const 1)
    )
   )
  )
  (func $unreachable-if-toplevel (type $5) (result i32)
   (if
    (i32.const 3)
-   (block $label$0
-    (return
-     (i32.const 2)
-    )
+   (return
+    (i32.const 2)
    )
-   (block $label$1
-    (return
-     (i32.const 1)
-    )
+   (return
+    (i32.const 1)
    )
   )
  )
  (func $unreachable-loop (type $5) (result i32)
-  (loop $label$0
+  (loop $label$1
    (nop)
    (return
     (i32.const 1)
@@ -542,14 +502,14 @@
   )
  )
  (func $unreachable-loop0 (type $5) (result i32)
-  (loop $label$0
+  (loop $label$1
    (return
     (i32.const 1)
    )
   )
  )
  (func $unreachable-loop-toplevel (type $5) (result i32)
-  (loop $label$0
+  (loop $label$1
    (nop)
    (return
     (i32.const 1)
@@ -557,26 +517,20 @@
   )
  )
  (func $unreachable-loop0-toplevel (type $5) (result i32)
-  (loop $label$0
+  (loop $label$1
    (return
     (i32.const 1)
    )
   )
  )
  (func $unreachable-ifs (type $1)
-  (block $label$0
-   (unreachable)
-  )
+  (unreachable)
  )
  (func $unreachable-if-arm (type $1)
   (if
    (i32.const 1)
-   (block $label$0
-    (nop)
-   )
-   (block $label$1
-    (unreachable)
-   )
+   (nop)
+   (unreachable)
   )
  )
 )