fix eliminator bug with eliminating over loops

3 files changed, 19 insertions, 6 deletions

diff --git a/tools/eliminator/eliminator-test-output.js b/tools/eliminator/eliminator-test-output.js
index da9be5cc..876340de 100644
--- a/tools/eliminator/eliminator-test-output.js
+++ b/tools/eliminator/eliminator-test-output.js
@@ -111,4 +111,11 @@ function f2() {
   var $8 = $_pre;
   c($8);
 }
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["f", "g", "h", "py", "r", "t", "f2"]
+function f3($s, $tree, $k) {
+  var $0 = HEAPU32[($s + 2908 + ($k << 2) | 0) >> 2];
+  while (1) {
+    HEAP32[($s + 2908 + ($storemerge_in << 2) | 0) >> 2] = $9;
+  }
+  HEAP32[($s + 2908 + ($storemerge_in << 2) | 0) >> 2] = $0;
+}
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["f", "g", "h", "py", "r", "t", "f2", "f3"]
diff --git a/tools/eliminator/eliminator-test.js b/tools/eliminator/eliminator-test.js
index 3410499d..4928134a 100644
--- a/tools/eliminator/eliminator-test.js
+++ b/tools/eliminator/eliminator-test.js
@@ -122,5 +122,13 @@ function f2() {
   var $8 = $_pre;
   c($8);
 }
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["f", "g", "h", "py", "r", "t", "f2"]
+function f3($s, $tree, $k) {
+  // HEAP vars alias each other, and the loop can confuse us
+  var $0 = HEAPU32[($s + 2908 + ($k << 2) | 0) >> 2];
+  while (1) {
+    HEAP32[($s + 2908 + ($storemerge_in << 2) | 0) >> 2] = $9;
+  }
+  HEAP32[($s + 2908 + ($storemerge_in << 2) | 0) >> 2] = $0;
+}
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["f", "g", "h", "py", "r", "t", "f2", "f3"]
 
diff --git a/tools/eliminator/eliminator.coffee b/tools/eliminator/eliminator.coffee
index 84e544b2..5b8ac43f 100644
--- a/tools/eliminator/eliminator.coffee
+++ b/tools/eliminator/eliminator.coffee
@@ -252,12 +252,10 @@ class Eliminator
             traverseChild child
         else
           # Don't put anything from outside into the body of a loop.
-          savedLive = isLive
           isLive = {}
           for child in node then traverseChild child
-          for name of isLive
-            if not isLive[name] then savedLive[name] = false
-          isLive = savedLive
+          # Don't keep anything alive through a loop
+          isLive = {}
         return node
       else if type is 'var'
         for [varName, varValue] in node[1]