Slightly improve pass pipeline (#1498)

Author: MaxGraey

src/module.ts

@@ -1526,11 +1526,12 @@ export class Module {
         passes.push("remove-unused-brs");
         passes.push("remove-unused-names");
         passes.push("merge-blocks");
-        passes.push("precompute");
+        passes.push("precompute-propagate");
       }
       if (optimizeLevel >= 3) {
         passes.push("flatten");
         passes.push("simplify-locals-notee-nostructure");
+        passes.push("merge-locals");
         passes.push("vacuum");
 
         passes.push("code-folding");
@@ -1548,12 +1549,11 @@ export class Module {
       passes.push("optimize-instructions");
       if (optimizeLevel >= 3 || shrinkLevel >= 1) {
         passes.push("dce");
-        passes.push("inlining");
       }
       passes.push("remove-unused-brs");
       passes.push("remove-unused-names");
-      passes.push("inlining-optimizing");
       if (optimizeLevel >= 3 || shrinkLevel >= 2) {
+        passes.push("inlining");
         passes.push("precompute-propagate");
       } else {
         passes.push("precompute");
@@ -1581,9 +1581,6 @@ export class Module {
         passes.push("merge-locals");
       }
       passes.push("vacuum");
-      if (optimizeLevel >= 3 || shrinkLevel >= 1) {
-        passes.push("code-folding");
-      }
       if (optimizeLevel >= 2 || shrinkLevel >= 1) {
         passes.push("simplify-globals-optimizing");
       }
@@ -1622,6 +1619,9 @@ export class Module {
         passes.push("simplify-globals");
         passes.push("vacuum");
       }
+      if (optimizeLevel >= 3 || shrinkLevel >= 1) {
+        passes.push("code-folding");
+      }
       // precompute works best after global optimizations
       if (optimizeLevel >= 2 || shrinkLevel >= 1) {
         passes.push("precompute-propagate");
@@ -1656,7 +1656,7 @@ export class Module {
           passes.push("simplify-locals");
           passes.push("vacuum");
 
-          passes.push("inlining-optimizing");
+          passes.push("inlining");
           passes.push("precompute-propagate");
           passes.push("vacuum");
 

tests/compiler/issues/1095.optimized.wat

@@ -952,16 +952,16 @@
   i32.const 16
   i32.add
   call $~lib/rt/pure/__retain
-  local.tee $3
+  local.tee $2
   i32.const 1200
   i32.store
-  local.get $3
+  local.get $2
   call $~lib/rt/pure/__retain
-  local.tee $1
-  local.set $2
-  local.get $1
-  i32.load
   local.tee $0
+  local.set $3
+  local.get $0
+  i32.load
+  local.tee $1
   i32.eqz
   if
    i32.const 1232
@@ -971,25 +971,25 @@
    call $~lib/builtins/abort
    unreachable
   end
+  local.get $1
   local.get $0
-  local.get $2
   i32.load
-  local.tee $2
+  local.tee $0
   i32.ne
   if
-   local.get $0
+   local.get $1
    call $~lib/rt/pure/__retain
-   local.set $0
-   local.get $2
+   local.set $1
+   local.get $0
    call $~lib/rt/pure/__release
   end
+  local.get $3
   local.get $1
-  local.get $0
   i32.store
-  local.get $1
-  call $~lib/rt/pure/__release
   local.get $3
   call $~lib/rt/pure/__release
+  local.get $2
+  call $~lib/rt/pure/__release
  )
  (func $~lib/rt/pure/decrement (param $0 i32)
   (local $1 i32)