Fixed code generation for LBranch on ARM when the operand's representation is double.

The condition code for branching on the result of vcmp was wrong, effectively
swapping the true/false branches.

TEST=regress-lbranch-double.js
Review URL: http://codereview.chromium.org/7553010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8784 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/lithium-codegen-arm.cc

@@ -1560,7 +1560,7 @@ void LCodeGen::DoBranch(LBranch* instr) {
     // Test the double value. Zero and NaN are false.
     __ VFPCompareAndLoadFlags(reg, 0.0, scratch);
     __ tst(scratch, Operand(kVFPZConditionFlagBit | kVFPVConditionFlagBit));
-    EmitBranch(true_block, false_block, ne);
+    EmitBranch(true_block, false_block, eq);
   } else {
     ASSERT(r.IsTagged());
     Register reg = ToRegister(instr->InputAt(0));

test/mjsunit/compiler/regress-lbranch-double.js

+// Copyright 2011 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
+
+// ARM's code generator for LBranch had a bug, swapping the true/false
+// branches when the representation of the condition is a double.
+
+function foo() {
+  return Math.sqrt(2.6415) ? 88 : 99;
+}
+
+assertEquals(88, foo());
+assertEquals(88, foo());
+%OptimizeFunctionOnNextCall(foo)
+assertEquals(88, foo());