Remove redundant instructions in Flatten (#2524)

When the expression type is none, it does not seem to be necessary to
make it a prelude and insert a nop. This also results in unnecessary
blocks that contains an expression with a nop, which can be reduced to
just the expression. This also adds some newlines to improve
readability.

1 files changed, 18 insertions, 34 deletions

diff --git a/test/passes/asyncify_mod-asyncify-always-and-only-unwind.txt b/test/passes/asyncify_mod-asyncify-always-and-only-unwind.txt
index 49c3ed7ed..f5c1ed1c0 100644
--- a/test/passes/asyncify_mod-asyncify-always-and-only-unwind.txt
+++ b/test/passes/asyncify_mod-asyncify-always-and-only-unwind.txt
@@ -44,35 +44,26 @@
         )
        )
       )
-      (block
-       (if
-        (if (result i32)
-         (i32.eq
-          (global.get $__asyncify_state)
-          (i32.const 0)
-         )
-         (i32.const 1)
-         (i32.eq
-          (local.get $1)
-          (i32.const 0)
-         )
-        )
-        (block
-         (call $import)
-         (if
-          (i32.const 1)
-          (br $__asyncify_unwind
-           (i32.const 0)
-          )
-         )
-        )
-       )
-       (if
+      (if
+       (if (result i32)
         (i32.eq
          (global.get $__asyncify_state)
          (i32.const 0)
         )
-        (nop)
+        (i32.const 1)
+        (i32.eq
+         (local.get $1)
+         (i32.const 0)
+        )
+       )
+       (block
+        (call $import)
+        (if
+         (i32.const 1)
+         (br $__asyncify_unwind
+          (i32.const 0)
+         )
+        )
        )
       )
      )
@@ -216,7 +207,6 @@
          (local.set $temp
           (local.get $1)
          )
-         (nop)
          (local.set $2
           (local.get $temp)
          )
@@ -227,7 +217,6 @@
        )
        (nop)
        (nop)
-       (nop)
       )
       (unreachable)
      )
@@ -379,14 +368,10 @@
          (global.get $__asyncify_state)
          (i32.const 0)
         )
-        (block
-         (drop
-          (local.get $0)
-         )
-         (nop)
+        (drop
+         (local.get $0)
         )
        )
-       (nop)
       )
      )
      (return)
@@ -441,7 +426,6 @@
   (drop
    (local.get $0)
   )
-  (nop)
  )
  (func $asyncify_start_unwind (; 7 ;) (param $0 i32)
   (global.set $__asyncify_state