MIPS: Fix unpredictable random failures after direct api function call.

src/mips64/assembler-mips64.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 1430 matching lines @@
                      (kImm26Bits + kImmFieldShift)) == 0;
     DCHECK(in_range && ((target & 3) == 0));
   }
 #endif
   positions_recorder()->WriteRecordedPositions();
   GenInstrJump(JAL, static_cast<uint32_t>(target >> 2) & kImm26Mask);
 }
 
 
 void Assembler::jalr(Register rs, Register rd) {
+  DCHECK(rs.code() != rd.code());
   BlockTrampolinePoolScope block_trampoline_pool(this);
   positions_recorder()->WriteRecordedPositions();
   GenInstrRegister(SPECIAL, rs, zero_reg, rd, 0, JALR);
   BlockTrampolinePoolFor(1);  // For associated delay slot.
 }
 
 
 void Assembler::jic(Register rt, int16_t offset) {
   DCHECK(kArchVariant == kMips64r6);
   Instr instr = POP66 | (JIC << kRsShift) | (rt.code() << kRtShift) |
@@ skipping 1777 matching lines @@
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
     CpuFeatures::FlushICache(pc, 4 * Assembler::kInstrSize);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64