MIPS64: Fix 'MIPS: Fix dd() implementations for compact branches.'

test/cctest/test-macro-assembler-mips64.cc

 // Copyright 2013 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.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
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@@ skipping 323 matching lines @@
     Label here;
 
     __ bal(&here);
     __ dsll(at, a0, 3);  // In delay slot.
     __ bind(&here);
     __ daddu(at, at, ra);
     __ ld(at, MemOperand(at, 6 * Assembler::kInstrSize));
     __ jalr(at);
     __ nop();  // Branch delay slot nop.
     __ bc(&done);
+    // A nop instruction must be generated by the forbidden slot guard
+    // (Assembler::dd(Label*)) so the first label goes to an 8 bytes aligned
+    // location.
     for (int i = 0; i < kNumCases; ++i) {
       __ dd(&labels[i]);
     }
   }
 
   for (int i = 0; i < kNumCases; ++i) {
     __ bind(&labels[i]);
     __ lui(v0, (values[i] >> 16) & 0xffff);
     __ ori(v0, v0, values[i] & 0xffff);
     __ jr(ra);
@@ skipping 181 matching lines @@
   for (size_t i = 0; i < nr_test_cases; ++i) {
     uint64_t res = run_dlsa(tc[i].rt, tc[i].rs, tc[i].sa);
     PrintF("0x%" PRIx64 " =? 0x%" PRIx64 " == Dlsa(v0, %" PRIx64 ", %" PRIx64
            ", %hhu)\n",
            tc[i].expected_res, res, tc[i].rt, tc[i].rs, tc[i].sa);
     CHECK_EQ(tc[i].expected_res, res);
   }
 }
 
 #undef __