Optimize alignment rounding.

Replace x>>2<<2 and x>>3<<3 with x&-4 and x&-8, respectively, since
an and is cheaper than two shifts.

1 files changed, 1 insertions, 1 deletions

diff --git a/emscripten.py b/emscripten.py
index 2b62c93a..2e90fa48 100755
--- a/emscripten.py
+++ b/emscripten.py
@@ -588,7 +588,7 @@ function stackAlloc(size) {
   var ret = 0;
   ret = STACKTOP;
   STACKTOP = (STACKTOP + size)|0;
-''' + ('STACKTOP = ((STACKTOP + 3)>>2)<<2;' if settings['TARGET_X86'] else 'STACKTOP = ((STACKTOP + 7)>>3)<<3;') + '''
+''' + ('STACKTOP = (STACKTOP + 3)&-4;' if settings['TARGET_X86'] else 'STACKTOP = (STACKTOP + 7)&-8;') + '''
   return ret|0;
 }
 function stackSave() {