Collect type feedback on result of Math.[round|ceil|floor]

test/mjsunit/math-round-minus-zero.js

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax --noalways-opt
+
+// Test that a -0 result doesn't cause deopt loops
+function noDeoptLoop(x) {
+  return Math.round(x);
+}
+assertEquals(0, noDeoptLoop(0.4));
+assertEquals(0, noDeoptLoop(0.4));
+assertEquals(0, noDeoptLoop(0.4));
+%OptimizeFunctionOnNextCall(noDeoptLoop);
+assertEquals(0, noDeoptLoop(0.4));
+assertEquals(0, noDeoptLoop(0.4));
+assertEquals(-Infinity, 1/noDeoptLoop(-0.4));
+assertUnoptimized(noDeoptLoop);
+assertEquals(-Infinity, 1/noDeoptLoop(-0.4));
+assertEquals(-Infinity, 1/noDeoptLoop(-0.0));
+assertEquals(-Infinity, 1/noDeoptLoop(-0.5));
+assertEquals(-1, noDeoptLoop(-1));
+assertEquals(-1, noDeoptLoop(-0.51));
+%OptimizeFunctionOnNextCall(noDeoptLoop);
+assertEquals(-Infinity, 1/noDeoptLoop(-0.4));
+assertEquals(-Infinity, 1/noDeoptLoop(-0.4));
+assertOptimized(noDeoptLoop);
+%ClearFunctionTypeFeedback(noDeoptLoop);
+%DeoptimizeFunction(noDeoptLoop);
+
+// Test that round that goes megamorphic is handled correctly.
+function notRound(x) {
+  return -x;
+}
+function testMega(f, x) {
+  return f(x);
+}
+assertEquals(7, testMega(Math.round, 7.4));
+assertEquals(7, testMega(Math.round, 7.4));
+assertEquals(7, testMega(Math.round, 7.4));
+assertEquals(-7.4, testMega(notRound, 7.4));
+
+// Make sure that we can learn about round specialization from Cranskhaft, which
+// doesn't insert soft deopts for CallICs.
+function crankRoundLearn(x) {
+  return Math.round(x);
+}
+%OptimizeFunctionOnNextCall(crankRoundLearn);
+assertEquals(12, crankRoundLearn(12.3));
+assertOptimized(crankRoundLearn);
+assertEquals(-Infinity, 1/crankRoundLearn(-0.4));
+assertOptimized(crankRoundLearn);
+assertEquals(-Infinity, 1/crankRoundLearn(-0.4));