move asm loop optimization into last phase

5 files changed, 37 insertions, 30 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;
diff --git a/tools/test-js-optimizer-asm-last-output.js b/tools/test-js-optimizer-asm-last-output.js
index c10cc6b0..02605db8 100644
--- a/tools/test-js-optimizer-asm-last-output.js
+++ b/tools/test-js-optimizer-asm-last-output.js
@@ -32,4 +32,9 @@ function finall(x) {
   a = -0xde0b6b000000000;
   return 12.0e10;
 }
+function looop() {
+  do {
+    do_it();
+  } while (!condition());
+}
 
diff --git a/tools/test-js-optimizer-asm-last.js b/tools/test-js-optimizer-asm-last.js
index 6e97b687..d3dffcae 100644
--- a/tools/test-js-optimizer-asm-last.js
+++ b/tools/test-js-optimizer-asm-last.js
@@ -32,4 +32,13 @@ function finall(x) {
   a = -0xde0b6b000000000;
   return +12e10;
 }
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["finall"]
+function looop() {
+  while (1) {
+    do_it();
+    if (condition()) {
+      break;
+    }
+  }
+}
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["finall", "looop"]
+
diff --git a/tools/test-js-optimizer-regs-output.js b/tools/test-js-optimizer-regs-output.js
index c1c9ec87..fe7de5fb 100644
--- a/tools/test-js-optimizer-regs-output.js
+++ b/tools/test-js-optimizer-regs-output.js
@@ -229,9 +229,4 @@ function __ZN14NetworkAddressC1EPKcti(r1) {
   __ZN14NetworkAddressC2EPKcti(r1);
   return;
 }
-function looop() {
-  do {
-    do_it();
-  } while (!condition());
-}
 
diff --git a/tools/test-js-optimizer-regs.js b/tools/test-js-optimizer-regs.js
index b38760cc..3013e518 100644
--- a/tools/test-js-optimizer-regs.js
+++ b/tools/test-js-optimizer-regs.js
@@ -234,12 +234,4 @@ function __ZN14NetworkAddressC1EPKcti($this) {
   __ZN14NetworkAddressC2EPKcti($this);
   return;
 }
-function looop() {
-  while (1) {
-    do_it();
-    if (condition()) {
-      break;
-    }
-  }
-}
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes", "atomic", "fcntl_open", "ex", "switchey", "__ZN14NetworkAddressC1EPKcti", "looop"]
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes", "atomic", "fcntl_open", "ex", "switchey", "__ZN14NetworkAddressC1EPKcti"]