handle multiple var defs of the same var in registerize

3 files changed, 35 insertions, 4 deletions

diff --git a/tools/js-optimizer.js b/tools/js-optimizer.js
index 57d62339..f968fec2 100644
--- a/tools/js-optimizer.js
+++ b/tools/js-optimizer.js
@@ -1150,7 +1150,10 @@ function registerize(ast, conservative) {
       if (type == 'var') {
         node[1].forEach(function(arg) {
           var name = arg[0];
-          varUses[name] = 1;
+          if (!varUses[name]) { // may have multiple var definitions
+            varUses[name] = 0;
+          }
+          varUses[name]++;
         });
       }
     });
@@ -1174,7 +1177,7 @@ function registerize(ast, conservative) {
     var loopRegs = [];
     var loops = 0;
     function decUse(name) {
-      if (!varUses[name]) return varRegs[name]; // no uses left, but still need to replace the name if it has a register
+      if (!varUses[name]) return false; // no uses left, or not a relevant variable
       var reg = varRegs[name];
       if (!reg) {
         // acquire register
diff --git a/tools/test-js-optimizer-regs-output.js b/tools/test-js-optimizer-regs-output.js
index c0c6c923..f3322e11 100644
--- a/tools/test-js-optimizer-regs-output.js
+++ b/tools/test-js-optimizer-regs-output.js
@@ -62,4 +62,18 @@ function primes() {
   return 1;
   return null;
 }
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes"]
+function atomic() {
+  var r1, r2, r3, r4;
+  r2 = STACKTOP;
+  STACKTOP += 4;
+  r1 = r2 >> 2;
+  HEAP32[r1] = 10;
+  r3 = (tempValue = HEAP32[r1], HEAP32[r1] == 10 && (HEAP32[r1] = 7), tempValue);
+  r4 = (r3 | 0) == 10 & 1;
+  r3 = HEAP32[r1];
+  r1 = _printf(STRING_TABLE.__str | 0, (tempInt = STACKTOP, STACKTOP += 8, HEAP32[tempInt >> 2] = r3, HEAP32[tempInt + 4 >> 2] = r4, tempInt));
+  STACKTOP = r2;
+  return 0;
+  return null;
+}
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes", "atomic"]
diff --git a/tools/test-js-optimizer-regs.js b/tools/test-js-optimizer-regs.js
index 1dd7b9d3..d54ce508 100644
--- a/tools/test-js-optimizer-regs.js
+++ b/tools/test-js-optimizer-regs.js
@@ -65,4 +65,18 @@ function primes() {
   return 1;
   return null;
 }
-// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes"]
+function atomic() {
+  var $x$s2;
+  var __stackBase__ = STACKTOP;
+  STACKTOP += 4;
+  var $x$s2 = __stackBase__ >> 2;
+  HEAP32[$x$s2] = 10;
+  var $0 = (tempValue = HEAP32[$x$s2], HEAP32[$x$s2] == 10 && (HEAP32[$x$s2] = 7), tempValue);
+  var $conv = ($0 | 0) == 10 & 1;
+  var $2 = HEAP32[$x$s2];
+  var $call = _printf(STRING_TABLE.__str | 0, (tempInt = STACKTOP, STACKTOP += 8, HEAP32[tempInt >> 2] = $2, HEAP32[tempInt + 4 >> 2] = $conv, tempInt));
+  STACKTOP = __stackBase__;
+  return 0;
+  return null;
+}
+// EMSCRIPTEN_GENERATED_FUNCTIONS: ["test", "primes", "atomic"]