[machine-operator-reducer] fix float truncation

test/mjsunit/math-52-mul-div.js

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --turbo-filter=*
+
+function mul(a, b) {
+  const l = a & 0x3ffffff;
+  const h = b & 0x3ffffff;
+
+  return (l * h) >>> 0;
+}
+
+function mulAndDiv(a, b) {
+  const l = a & 0x3ffffff;
+  const h = b & 0x3ffffff;
+  const m = l * h;
+
+  const rl = m & 0x3ffffff;
+  const rh = (m / 0x4000000) >>> 0;
+
+  return rl | rh;
+}
+
+function overflowMul(a, b) {
+  const l = a | 0;
+  const h = b | 0;
+
+  return (l * h) >>> 0;
+}
+
+function overflowDiv(a, b) {
+  const l = a & 0x3ffffff;
+  const h = b & 0x3ffffff;
+  const m = l * h;
+
+  return (m / 0x10) >>> 0;
+}
+
+function nonPowerOfTwoDiv(a, b) {
+  const l = a & 0x3ffffff;
+  const h = b & 0x3ffffff;
+  const m = l * h;
+
+  return (m / 0x4000001) >>> 0;
+}
+
+function test(fn, a, b, sets) {
+  const expected = fn(a, b);
+  fn(1, 2);
+  fn(0, 0);
+  %OptimizeFunctionOnNextCall(fn);
+  const actual = fn(a, b);
+
+  assertEquals(expected, actual);
+
+  sets.forEach(function(set, i) {
+    assertEquals(set.expected, fn(set.a, set.b), fn.name + ', set #' + i);
+  });
+}
+
+test(mul, 0x3ffffff, 0x3ffffff, [
+  { a: 0, b: 0, expected: 0 },
+  { a: 0xdead, b: 0xbeef, expected: 0xa6144983 },
+  { a: 0x1aa1dea, b: 0x2badead, expected: 0x35eb2322 }
+]);
+test(mulAndDiv, 0x3ffffff, 0x3ffffff, [
+  { a: 0, b: 0, expected: 0 },
+  { a: 0xdead, b: 0xbeef, expected: 0x21449ab },
+  { a: 0x1aa1dea, b: 0x2badead, expected: 0x1ebf32f }
+]);
+test(overflowMul, 0x4ffffff, 0x4ffffff, [
+  { a: 0, b: 0, expected: 0 },
+  { a: 0xdead, b: 0xbeef, expected: 0xa6144983 },
+  { a: 0x1aa1dea, b: 0x2badead, expected: 0x35eb2322 }
+]);
+test(overflowDiv, 0x3ffffff, 0x3ffffff, [
+  { a: 0, b: 0, expected: 0 },
+  { a: 0xdead, b: 0xbeef, expected: 0xa614498 },
+  { a: 0x1aa1dea, b: 0x2badead, expected: 0x835eb232 }
+]);
+test(nonPowerOfTwoDiv, 0x3ffffff, 0x3ffffff, [
+  { a: 0, b: 0, expected: 0 },
+  { a: 0xdead, b: 0xbeef, expected: 0x29 },
+  { a: 0x1aa1dea, b: 0x2badead, expected: 0x122d20d }
+]);