move asm loop optimization into last phase

1 files changed, 21 insertions, 15 deletions

diff --git a/tools/js-optimizer.js b/tools/js-optimizer.js
index 57c9cf79..df71ab86 100644
--- a/tools/js-optimizer.js
+++ b/tools/js-optimizer.js
@@ -1805,21 +1805,6 @@ function registerize(ast) {
       }
       denormalizeAsm(fun, finalAsmData);
     }
-
-    // Post-registerize optimizations. This is near the end of the pipeline, we can assume all other optimizations except for minification are done
-    traverse(fun, function(node, type) {
-      if (type == 'while' && node[1][0] == 'num' && node[1][1] == 1 && node[2][0] == 'block') {
-        // while (1) { .. if (..) { break } } ==> do { .. } while(..)
-        var stats = node[2][1];
-        var last = stats[stats.length-1];
-        if (last[0] == 'if' && !last[3] && last[2][0] == 'block' && last[2][1][0][0] == 'break' && !last[2][1][0][1]) {
-          var conditionToBreak = last[1];
-          stats.pop();
-          node[0] = 'do';
-          node[1] = simplifyNotComps(['unary-prefix', '!', conditionToBreak]);
-        }
-      }
-    });
   });
 }
 
@@ -2471,6 +2456,26 @@ function fixDotZero(js) {
   });
 }
 
+function asmLoopOptimizer(ast) {
+  traverseGeneratedFunctions(ast, function(fun) {
+    // This is at the end of the pipeline, we can assume all other optimizations are done, and we modify loops
+    // into shapes that might confuse other passes
+    traverse(fun, function(node, type) {
+      if (type == 'while' && node[1][0] == 'num' && node[1][1] == 1 && node[2][0] == 'block') {
+        // while (1) { .. if (..) { break } } ==> do { .. } while(..)
+        var stats = node[2][1];
+        var last = stats[stats.length-1];
+        if (last[0] == 'if' && !last[3] && last[2][0] == 'block' && last[2][1][0][0] == 'break' && !last[2][1][0][1]) {
+          var conditionToBreak = last[1];
+          stats.pop();
+          node[0] = 'do';
+          node[1] = simplifyNotComps(['unary-prefix', '!', conditionToBreak]);
+        }
+      }
+    });
+  });
+}
+
 // Passes table
 
 var compress = false, printMetadata = true, asm = false, last = false;
@@ -2514,6 +2519,7 @@ arguments_.slice(1).forEach(function(arg) {
   passes[arg](ast);
 });
 if (asm && last) {
+  asmLoopOptimizer(ast);
   prepDotZero(ast);
 }
 var js = astToSrc(ast, compress), old;