[pipeline] Add early inline pass (#2117)

Author: MaxGraey

src/module.ts

@@ -2298,6 +2298,7 @@ export class Module {
       // --- PassRunner::addDefaultFunctionOptimizationPasses ---
       if (optimizeLevel >= 2) {
         passes.push("once-reduction");
+        passes.push("inlining");
       }
       if (optimizeLevel >= 3 || shrinkLevel >= 1) {
         passes.push("rse");

tests/compiler/NonNullable.optimized.wat

@@ -23,6 +23,7 @@
   (local $2 i32)
   (local $3 i32)
   (local $4 i32)
+  (local $5 i32)
   local.get $0
   local.get $1
   i32.eq
@@ -57,47 +58,47 @@
    i32.const 0
    return
   end
-  block $__inlined_func$~lib/util/string/compareImpl (result i32)
-   local.get $0
-   local.tee $2
-   i32.const 7
-   i32.and
-   local.get $1
-   i32.const 7
-   i32.and
-   i32.or
-   i32.eqz
-   local.get $3
-   local.tee $0
-   i32.const 4
-   i32.ge_u
-   i32.and
-   if
-    loop $do-loop|0
+  local.get $0
+  local.tee $2
+  i32.const 7
+  i32.and
+  local.get $1
+  i32.const 7
+  i32.and
+  i32.or
+  i32.eqz
+  local.get $3
+  local.tee $0
+  i32.const 4
+  i32.ge_u
+  i32.and
+  if
+   loop $do-loop|0
+    local.get $2
+    i64.load
+    local.get $1
+    i64.load
+    i64.eq
+    if
      local.get $2
-     i64.load
+     i32.const 8
+     i32.add
+     local.set $2
      local.get $1
-     i64.load
-     i64.eq
-     if
-      local.get $2
-      i32.const 8
-      i32.add
-      local.set $2
-      local.get $1
-      i32.const 8
-      i32.add
-      local.set $1
-      local.get $0
-      i32.const 4
-      i32.sub
-      local.tee $0
-      i32.const 4
-      i32.ge_u
-      br_if $do-loop|0
-     end
+     i32.const 8
+     i32.add
+     local.set $1
+     local.get $0
+     i32.const 4
+     i32.sub
+     local.tee $0
+     i32.const 4
+     i32.ge_u
+     br_if $do-loop|0
     end
    end
+  end
+  block $__inlined_func$~lib/util/string/compareImpl
    loop $while-continue|1
     local.get $0
     local.tee $3
@@ -108,17 +109,16 @@
     if
      local.get $2
      i32.load16_u
-     local.tee $3
+     local.tee $5
      local.get $1
      i32.load16_u
      local.tee $4
+     i32.sub
+     local.set $3
+     local.get $4
+     local.get $5
      i32.ne
-     if
-      local.get $3
-      local.get $4
-      i32.sub
-      br $__inlined_func$~lib/util/string/compareImpl
-     end
+     br_if $__inlined_func$~lib/util/string/compareImpl
      local.get $2
      i32.const 2
      i32.add
@@ -131,16 +131,18 @@
     end
    end
    i32.const 0
+   local.set $3
   end
+  local.get $3
   i32.eqz
  )
  (func $~start
   (local $0 i32)
-  global.get $~lib/memory/__stack_pointer
-  i32.const 12
-  i32.sub
-  global.set $~lib/memory/__stack_pointer
   block $folding-inner1
+   global.get $~lib/memory/__stack_pointer
+   i32.const 12
+   i32.sub
+   global.set $~lib/memory/__stack_pointer
    block $folding-inner0
     global.get $~lib/memory/__stack_pointer
     i32.const 1324