Fix Math.pow(-0, 0.5) and Math.pow(-0, -0.5). These are not equal to sqrt(-0...

src/arm/codegen-arm.cc

 // Copyright 2010 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
@@ skipping 4680 matching lines @@
     // Compare exponent with -0.5.
     __ cmp(scratch1, Operand(0xbfe00000));
     __ b(ne, &not_minus_half);
 
     // Get the double value from the base into vfp register d0.
     __ ObjectToDoubleVFPRegister(base, d0,
                                  scratch1, scratch2, heap_number_map, s0,
                                  runtime.entry_label(),
                                  AVOID_NANS_AND_INFINITIES);
 
+    // Convert -0 into +0 by adding +0.
+    __ vmov(d2, 0.0);
+    __ vadd(d0, d2, d0);
     // Load 1.0 into d2.
     __ vmov(d2, 1.0);
 
-    // Calculate the reciprocal of the square root. 1/sqrt(x) = sqrt(1/x).
+    // Calculate the reciprocal of the square root.
+    __ vsqrt(d0, d0);
     __ vdiv(d0, d2, d0);
-    __ vsqrt(d0, d0);
 
     __ b(&allocate_return);
 
     __ bind(&not_minus_half);
     // Compare exponent with 0.5.
     __ cmp(scratch1, Operand(0x3fe00000));
     runtime.Branch(ne);
 
       // Get the double value from the base into vfp register d0.
     __ ObjectToDoubleVFPRegister(base, d0,
                                  scratch1, scratch2, heap_number_map, s0,
                                  runtime.entry_label(),
                                  AVOID_NANS_AND_INFINITIES);
+    // Convert -0 into +0 by adding +0.
+    __ vmov(d2, 0.0);
+    __ vadd(d0, d2, d0);
     __ vsqrt(d0, d0);
 
     __ bind(&allocate_return);
     Register scratch3 = r5;
     __ AllocateHeapNumberWithValue(scratch3, d0, scratch1, scratch2,
                                    heap_number_map, runtime.entry_label());
     __ mov(base, scratch3);
     done.Jump();
 
     runtime.Bind();
@@ skipping 2633 matching lines @@
                BinaryOpIC::GetName(runtime_operands_type_));
   return name_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM