Improve check elimination with branch sensitivity on HCompareObjectEqAndBranch.

test/mjsunit/compiler/compare_objeq_elim.js

 // Copyright 2010 the V8 project authors. All rights reserved.
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 // 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.
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 //       copyright notice, this list of conditions and the following
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 //
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 // "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 --check-elimination
 
-a = {
-  f: function() { this.y = 3; }
-};
-b = {
-  f: function() { this.y = 4; }
-};
-
-function x(z) {
-  return z.f();
+function A(x, y) {
+  this.x = x;
+  this.y = y;
 }
 
-x(a);
-x(b);
-x(a);
-x(b);
-x(a);
-x(b);
+function B(x, y) {
+  this.x = x;
+  this.y = y;
+}
 
-%OptimizeFunctionOnNextCall(x)
+function F1(a, b) {
+  if (a == b) return a.x;
+  else return b.x;
+}
 
-x(a);
-x(b);
+function F2(a, b) {
+  if (a == b) return a.x;
+  else return b.x;
+}
+
+function F3(a, b) {
+  var f = a.y;
+  if (a == b) return a.x;
+  else return b.x;
+}
+
+function F4(a, b) {
+  var f = b.y;
+  if (a == b) return a.x;
+  else return b.x;
+}
+
+%NeverOptimizeFunction(test);
+
+function test(f, a, b) {
+  f(a, a);
+  f(a, b);
+  f(b, a);
+  f(b, c);
+  f(b, b);
+  f(c, c);
+
+  %OptimizeFunctionOnNextCall(f)
+
+  assertEquals(a.x, f(a, a));
+  assertEquals(b.x, f(b, b));
+}
+
+var a = new A(3, 5);
+var b = new B(2, 6);
+var c = new A(1, 7);
+
+test(F1, a, c);
+test(F2, a, b);
+test(F3, a, b);
+test(F4, a, b);