[snapshot] do not embed string addresses in code.

src/mips/assembler-mips.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 1956 matching lines @@
 void Assembler::stop(const char* msg, uint32_t code) {
   DCHECK(code > kMaxWatchpointCode);
   DCHECK(code <= kMaxStopCode);
 #if V8_HOST_ARCH_MIPS
   break_(0x54321);
 #else  // V8_HOST_ARCH_MIPS
   BlockTrampolinePoolFor(2);
   // The Simulator will handle the stop instruction and get the message address.
   // On MIPS stop() is just a special kind of break_().
   break_(code, true);
-  emit(reinterpret_cast<Instr>(msg));
+  // Do not embed the message string address! We used to do this, but that
+  // made snapshots created from position-independent executable builds
+  // non-deterministic.
+  // TODO(yangguo): remove this field entirely.
+  nop();
 #endif
 }
 
 
 void Assembler::tge(Register rs, Register rt, uint16_t code) {
   DCHECK(is_uint10(code));
   Instr instr = SPECIAL | TGE | rs.code() << kRsShift
       | rt.code() << kRtShift | code << 6;
   emit(instr);
 }
@@ skipping 1200 matching lines @@
 
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
     Assembler::FlushICache(isolate, pc, 2 * sizeof(int32_t));
   }
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS