Emit VMLS for multiply-subtract on ARM.

test/cctest/test-assembler-arm.cc

 // 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
@@ skipping 247 matching lines @@
     __ stm(db_w, sp, r4.bit() | fp.bit() | lr.bit());
     __ sub(fp, ip, Operand(4));
 
     __ mov(r4, Operand(r0));
     __ vldr(d6, r4, OFFSET_OF(T, a));
     __ vldr(d7, r4, OFFSET_OF(T, b));
     __ vadd(d5, d6, d7);
     __ vstr(d5, r4, OFFSET_OF(T, c));
 
     __ vmla(d5, d6, d7);
+    __ vmls(d5, d5, d6);
 
     __ vmov(r2, r3, d5);
     __ vmov(d4, r2, r3);
     __ vstr(d4, r4, OFFSET_OF(T, b));
 
     // Load t.x and t.y, switch values, and store back to the struct.
     __ vldr(s0, r4, OFFSET_OF(T, x));
     __ vldr(s31, r4, OFFSET_OF(T, y));
     __ vmov(s16, s0);
     __ vmov(s0, s31);
@@ skipping 69 matching lines @@
     CHECK_EQ(9.0, t.x);
     CHECK_EQ(-123.456, t.n);
     CHECK_EQ(2718.2818, t.m);
     CHECK_EQ(2, t.i);
     CHECK_EQ(2718.2818, t.g);
     CHECK_EQ(31415926.5, t.h);
     CHECK_EQ(42.0, t.f);
     CHECK_EQ(1.0, t.e);
     CHECK_EQ(1.000000059604644775390625, t.d);
     CHECK_EQ(4.25, t.c);
-    CHECK_EQ(8.375, t.b);
+    CHECK_EQ(-4.1875, t.b);
     CHECK_EQ(1.5, t.a);
   }
 }
 
 
 TEST(5) {
   // Test the ARMv7 bitfield instructions.
   InitializeVM();
   v8::HandleScope scope;
 
@@ skipping 783 matching lines @@
     CHECK_EQ(2.75, t.x);
     CHECK_EQ(1.5, t.y);
     CHECK_EQ(17.0, t.z);
     CHECK_EQ(14.7610017472335499, t.i);
     CHECK_EQ(16.0, t.j);
     CHECK_EQ(73.8818412254460241, t.k);
   }
 }
 
 #undef __