MIPS: Added the stop() instruction with same behavior as on Arm simulator.

src/mips/constants-mips.h

 // Copyright 2010 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 140 matching lines @@
 // On MIPS all instructions are 32 bits.
 typedef int32_t Instr;
 
 // Special Software Interrupt codes when used in the presence of the MIPS
 // simulator.
 enum SoftwareInterruptCodes {
   // Transition to C code.
   call_rt_redirected = 0xfffff
 };
 
+// On MIPS Simulator breakpoints can have different codes:
+// - Breaks between 0 and kMaxWatchpointCode are treated as simple watchpoints,
+//   the simulator will run through them and print the registers.
+// - Breaks between kMaxWatchpointCode and kMaxStopCode are treated as stop()
+//   instructions (see Assembler::stop()).
+// - Breaks larger than kMaxStopCode are simple breaks, dropping you into the
+//   debugger.
+static const uint32_t kMaxWatchpointCode = 31;
+static const uint32_t kMaxStopCode = 127;
+STATIC_ASSERT(kMaxWatchpointCode < kMaxStopCode);
+
+
 // ----- Fields offset and length.
 static const int kOpcodeShift   = 26;
 static const int kOpcodeBits    = 6;
 static const int kRsShift       = 21;
 static const int kRsBits        = 5;
 static const int kRtShift       = 16;
 static const int kRtBits        = 5;
 static const int kRdShift       = 11;
 static const int kRdBits        = 5;
 static const int kSaShift       = 6;
@@ skipping 559 matching lines @@
 
 static const int kDoubleAlignmentBits = 3;
 static const int kDoubleAlignment = (1 << kDoubleAlignmentBits);
 static const int kDoubleAlignmentMask = kDoubleAlignment - 1;
 
 
 } }   // namespace v8::internal
 
 #endif    // #ifndef V8_MIPS_CONSTANTS_H_