wasm2js: Do not convert x >>> 0 | 0 to x >>> 0 (#2581)

isBinary was used where we should only accept
a signed binary, as removing the | 0 from an unsigned
value may be incorrect.

This does regress a few small things (as can be seen
in the diff). If it's important we can add more sophisticated
optimizations here, perhaps like an assumption that the
signedness of a local never matters.

Fixes emscripten-core/emscripten#10173

1 files changed, 4 insertions, 4 deletions

diff --git a/test/wasm2js/stack-modified.2asm.js.opt b/test/wasm2js/stack-modified.2asm.js.opt
index d321f6f67..2cd863f72 100644
--- a/test/wasm2js/stack-modified.2asm.js.opt
+++ b/test/wasm2js/stack-modified.2asm.js.opt
@@ -52,15 +52,15 @@ function asmFunc(global, env, buffer) {
  
  function _ZN17compiler_builtins3int3mul3Mul3mul17h070e9a1c69faec5bE($0_1, $1, $2, $3) {
   var $4 = 0, $5 = 0, $6 = 0, $7 = 0, $8 = 0, $9 = 0;
-  $4 = $2 >>> 16;
-  $5 = $0_1 >>> 16;
+  $4 = $2 >>> 16 | 0;
+  $5 = $0_1 >>> 16 | 0;
   $9 = Math_imul($4, $5);
   $6 = $2 & 65535;
   $7 = $0_1 & 65535;
   $8 = Math_imul($6, $7);
-  $5 = ($8 >>> 16) + Math_imul($5, $6) | 0;
+  $5 = ($8 >>> 16 | 0) + Math_imul($5, $6) | 0;
   $4 = ($5 & 65535) + Math_imul($4, $7) | 0;
-  $0_1 = (((Math_imul($1, $2) + $9 | 0) + Math_imul($0_1, $3) | 0) + ($5 >>> 16) | 0) + ($4 >>> 16) | 0;
+  $0_1 = (Math_imul($1, $2) + $9 | 0) + Math_imul($0_1, $3) + ($5 >>> 16) + ($4 >>> 16) | 0;
   $1 = $8 & 65535 | $4 << 16;
   i64toi32_i32$HIGH_BITS = $0_1;
   return $1;