Check for NaN in inlined versions of Math.min, Math.max.

R=danno@chromium.org
BUG=V8:2056
TEST=mjsunit/regress/regress-2056.js

Review URL: https://chromiumcodereview.appspot.com/10006008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11237 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen.cc

@@ -5730,7 +5730,27 @@ bool HGraphBuilder::TryInlineBuiltinMethodCall(Call* expr,
         set_current_block(return_left);
         Push(left);
         set_current_block(return_right);
-        Push(right);
+        // The branch above always returns the right operand if either of
+        // them is NaN, but the spec requires that max/min(NaN, X) = NaN.
+        // We add another branch that checks if the left operand is NaN or not.
+        if (left_operand->representation().IsDouble()) {
+          // If left_operand != left_operand then it is NaN.
+          HCompareIDAndBranch* compare_nan = new(zone()) HCompareIDAndBranch(
+              left_operand, left_operand, Token::EQ);
+          compare_nan->SetInputRepresentation(left_operand->representation());
+          HBasicBlock* left_is_number = graph()->CreateBasicBlock();
+          HBasicBlock* left_is_nan = graph()->CreateBasicBlock();
+          compare_nan->SetSuccessorAt(0, left_is_number);
+          compare_nan->SetSuccessorAt(1, left_is_nan);
+          current_block()->Finish(compare_nan);
+          set_current_block(left_is_nan);
+          Push(left);
+          set_current_block(left_is_number);
+          Push(right);
+          return_right = CreateJoin(left_is_number, left_is_nan, expr->id());
+        } else {
+          Push(right);
+        }
 
         HBasicBlock* join = CreateJoin(return_left, return_right, expr->id());
         set_current_block(join);

test/mjsunit/regress/regress-2056.js

+// Copyright 2012 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
+
+var cases = [
+    [0.0, 0.0, 0.0, 0,0],
+    [undefined, 0.0, NaN, NaN],
+    [0.0, undefined, NaN, NaN],
+    [NaN, 0.0, NaN, NaN],
+    [0.0, NaN, NaN, NaN],
+    [-NaN, 0.0, NaN, NaN],
+    [0.0, -NaN, NaN, NaN],
+    [Infinity, 0.0, Infinity, 0.0],
+    [0.0, Infinity, Infinity, 0.0],
+    [-Infinity, 0.0, 0.0, -Infinity],
+    [0.0, -Infinity, 0.0, -Infinity]
+];
+
+function do_min(a, b) {
+    return Math.min(a, b);
+}
+
+function do_max(a, b) {
+    return Math.max(a, b);
+}
+
+// Make sure that non-crankshaft results match expectations.
+for (i = 0; i < cases.length; ++i) {
+    var c = cases[i];
+    assertEquals(c[3], do_min(c[0], c[1]));
+    assertEquals(c[2], do_max(c[0], c[1]));
+}
+
+// Make sure that crankshaft results match expectations.
+for (i = 0; i < cases.length; ++i) {
+    var c = cases[i];
+    %OptimizeFunctionOnNextCall(do_min);
+    %OptimizeFunctionOnNextCall(do_max);
+    assertEquals(c[3], do_min(c[0], c[1]));
+    assertEquals(c[2], do_max(c[0], c[1]));
+}