Fixed issue v8:1644 (bug in the chaining of fixup position)

test/cctest/test-assembler-mips.cc

 // 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
@@ skipping 1241 matching lines @@
   CHECK(GET_FPU_ERR(t.type##_err4_out) & kFCSRInvalidOpFlagMask); \
   CHECK_EQ(kFPUInvalidResult, t.type##_invalid_result);
 
     CHECK_ROUND_RESULT(round);
     CHECK_ROUND_RESULT(floor);
     CHECK_ROUND_RESULT(ceil);
     CHECK_ROUND_RESULT(cvt);
   }
 }
 
+
+TEST(MIPS15) {
+  // Test chaining of label usages within instructions (issue 1644).
+  InitializeVM();
+  v8::HandleScope scope;
+  Assembler assm(Isolate::Current(), NULL, 0);
+
+  Label target;
+  __ beq(v0, v1, &target);
+  __ bne(v0, v1, &target);
+  __ bind(&target);
+  __ nop();
+}
+
 #undef __