make ctpop_i32 and 64 asm.js methods

Author: kripken

src/library.js

@@ -916,20 +916,24 @@ LibraryManager.library = {
     {{{ makeStructuralReturn(['ret', '0']) }}};
   },
 
+  llvm_ctpop_i32__asm: true,
+  llvm_ctpop_i32__sig: 'ii',
   llvm_ctpop_i32: function(x) {
     // http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
-    x = x|0;
-    x = x - ((x >>> 1) & 0x55555555)|0;
-    x = (x & 0x33333333) + ((x >>> 2) & 0x33333333)|0;
-
-    // next line is asm.js friendly, but unfortunatelly gives WRONG result
-    // return (((x + (x >>> 4) & 0xF0F0F0F)|0 * 0x1010101) >>> 24)|0;
-    return (((x + (x >>> 4) & 0xF0F0F0F) * 0x1010101) >>> 24)|0;
+    // http://bits.stephan-brumme.com/countBits.html
+    x = x | 0;
+    x = x - ((x >>> 1) & 0x55555555) | 0;
+    x = (x & 0x33333333) + ((x >>> 2) & 0x33333333) | 0;
+    return (Math_imul((x + (x >>> 4) & 252645135 /* 0xF0F0F0F, but hits uglify parse bug? */), 0x1010101) >>> 24) | 0;
   },
 
   llvm_ctpop_i64__deps: ['llvm_ctpop_i32'],
+  llvm_ctpop_i64__asm: true,
+  llvm_ctpop_i64__sig: 'iii',
   llvm_ctpop_i64: function(l, h) {
-    return _llvm_ctpop_i32(l) + _llvm_ctpop_i32(h);
+    l = l | 0;
+    h = h | 0;
+    return (_llvm_ctpop_i32(l) | 0) + (_llvm_ctpop_i32(h) | 0) | 0;
   },
 
   llvm_trap: function() {