* Handle 10 and 20-bit versions of Break instruction. Move handling

* of special values from signal_exception() in interp.c into mips.igen.
*
* Modified: gencode.c interp.c mips.igen sim-main.h

4 files changed, 68 insertions, 45 deletions

diff --git a/sim/mips/gencode.c b/sim/mips/gencode.c
index 928b88e..2e5ed28 100644
--- a/sim/mips/gencode.c
+++ b/sim/mips/gencode.c
@@ -2716,6 +2716,24 @@ build_instruction (doisa, features, mips16, insn)
      break ;
 
     case BREAK:
+
+     printf("    unsigned int break_code = instruction & HALT_INSTRUCTION_MASK;\n");
+     printf("    if (   break_code == (HALT_INSTRUCTION  & HALT_INSTRUCTION_MASK)\n");
+     printf("        || break_code == (HALT_INSTRUCTION2 & HALT_INSTRUCTION_MASK))\n");
+     printf("      {\n");
+     printf("        sim_engine_halt (SD, CPU, NULL, cia,\n");
+     printf("                         sim_exited, (unsigned int)(A0 & 0xFFFFFFFF));\n");
+     printf("      }\n");
+     printf("    else if (   break_code == (BREAKPOINT_INSTRUCTION  & HALT_INSTRUCTION_MASK)\n");
+     printf("             || break_code == (BREAKPOINT_INSTRUCTION2 & HALT_INSTRUCTION_MASK))\n");
+     printf("      {\n");
+     printf("        if (STATE & simDELAYSLOT)\n");
+     printf("          PC = cia - 4; /* reference the branch instruction */\n");
+     printf("        else\n");
+     printf("          PC = cia;\n");
+     printf("        sim_engine_halt (SD, CPU, NULL, cia, sim_stopped, SIM_SIGTRAP);\n");
+     printf("    }\n");
+
      printf("   SignalException(BreakPoint,instruction);\n");
      break ;
 
diff --git a/sim/mips/interp.c b/sim/mips/interp.c
index 07b7e6b..f35674a 100644
--- a/sim/mips/interp.c
+++ b/sim/mips/interp.c
@@ -110,23 +110,11 @@ char* pr_uword64 PARAMS ((uword64 addr));
 #define RSVD_INSTRUCTION_ARG_MASK  0xFFFFF  
 
 
-/* The following reserved instruction value is used when a simulator
-   halt is required.  NOTE: Care must be taken, since this value may
-   be used in later revisions of the MIPS ISA. */
-#define HALT_INSTRUCTION       (0x03ff000d)
-#define HALT_INSTRUCTION2      (0x0000ffcd)
-#define HALT_INSTRUCTION_MASK  (0x03FFFFC0)
-
-
 /* Bits in the Debug register */
 #define Debug_DBD 0x80000000   /* Debug Branch Delay */
 #define Debug_DM  0x40000000   /* Debug Mode         */
 #define Debug_DBp 0x00000002   /* Debug Breakpoint indicator */
 
-
-
-
-
 /*---------------------------------------------------------------------------*/
 /*-- GDB simulator interface ------------------------------------------------*/
 /*---------------------------------------------------------------------------*/
@@ -1839,33 +1827,6 @@ signal_exception (SIM_DESC sd,
        sim_io_eprintf(sd,"ReservedInstruction at PC = 0x%s\n", pr_addr (cia));
      }
 
-    case BreakPoint:
-#ifdef DEBUG
-      sim_io_printf(sd,"DBG: SignalException(%d) PC = 0x%s\n",exception,pr_addr(cia));
-#endif /* DEBUG */
-      /* Keep a copy of the current A0 in-case this is the program exit
-	 breakpoint:  */
-      {
-	va_list ap;
-	unsigned int instruction;
-	va_start(ap, exception);
-	instruction = va_arg(ap,unsigned int);
-	va_end(ap);
-	/* Check for our special terminating BREAK: */
-	if ((instruction & HALT_INSTRUCTION_MASK) == (HALT_INSTRUCTION & HALT_INSTRUCTION_MASK) ||
-	    (instruction & HALT_INSTRUCTION_MASK) == (HALT_INSTRUCTION2 & HALT_INSTRUCTION_MASK))
-	  {
-	    sim_engine_halt (SD, CPU, NULL, cia,
-			     sim_exited, (unsigned int)(A0 & 0xFFFFFFFF));
-	  }
-      }
-      if (STATE & simDELAYSLOT)
-	PC = cia - 4; /* reference the branch instruction */
-      else
-	PC = cia;
-      sim_engine_halt (SD, CPU, NULL, cia,
-		       sim_stopped, SIM_SIGTRAP);
-
     default:
      /* Store exception code into current exception id variable (used
         by exit code): */
@@ -1964,6 +1925,7 @@ signal_exception (SIM_DESC sd,
 	 sim_engine_halt (SD, CPU, NULL, NULL_CIA,
 			  sim_stopped, SIM_SIGFPE);
 
+       case BreakPoint:
        case SystemCall:
        case Trap:
 	 sim_engine_restart (SD, CPU, NULL, PC);
@@ -1974,11 +1936,6 @@ signal_exception (SIM_DESC sd,
 	 sim_engine_halt (SD, CPU, NULL, NULL_CIA,
 			  sim_stopped, SIM_SIGTRAP);
 
-       case BreakPoint:
-	 PC = EPC;
-	 sim_engine_abort (SD, CPU, NULL_CIA,
-			   "FATAL: Should not encounter a breakpoint\n");
-
        default : /* Unknown internal exception */
 	 PC = EPC;
 	 sim_engine_halt (SD, CPU, NULL, NULL_CIA,
diff --git a/sim/mips/mips.igen b/sim/mips/mips.igen
index 10ed6b8..d6b247c 100644
--- a/sim/mips/mips.igen
+++ b/sim/mips/mips.igen
@@ -941,6 +941,36 @@
 *tx19:
 // end-sanitize-tx19
 {
+  /* Check for some break instruction which are reserved for use by the simulator.  */
+  unsigned int break_code = instruction_0 & HALT_INSTRUCTION_MASK;
+  if (break_code == (HALT_INSTRUCTION  & HALT_INSTRUCTION_MASK) ||
+      break_code == (HALT_INSTRUCTION2 & HALT_INSTRUCTION_MASK))
+    {
+      sim_engine_halt (SD, CPU, NULL, cia,
+                       sim_exited, (unsigned int)(A0 & 0xFFFFFFFF));
+    }
+  else if (break_code == (BREAKPOINT_INSTRUCTION  & HALT_INSTRUCTION_MASK) ||
+           break_code == (BREAKPOINT_INSTRUCTION2 & HALT_INSTRUCTION_MASK))
+    {
+      if (STATE & simDELAYSLOT)
+        PC = cia - 4; /* reference the branch instruction */
+      else
+        PC = cia;
+      sim_engine_halt (SD, CPU, NULL, cia, sim_stopped, SIM_SIGTRAP);
+    }
+// start-sanitize-sky
+  else if (break_code == (HALT_INSTRUCTION_PASS & HALT_INSTRUCTION_MASK))
+    {
+      sim_engine_halt (SD, CPU, NULL, cia, sim_exited, 0);
+    }
+  else if (break_code == (HALT_INSTRUCTION_FAIL & HALT_INSTRUCTION_MASK))
+    {
+      sim_engine_halt (SD, CPU, NULL, cia, sim_exited, 15);
+    }
+// end-sanitize-sky
+
+  /* If we get this far, we're not an instruction reserved by the sim.  Raise 
+     the exception. */
   SignalException(BreakPoint, instruction_0);
 }
 
diff --git a/sim/mips/sim-main.h b/sim/mips/sim-main.h
index 295b127..4a632ab 100644
--- a/sim/mips/sim-main.h
+++ b/sim/mips/sim-main.h
@@ -212,7 +212,7 @@ typedef struct _hilo_history {
 #define ALU32_END(ANS) \
   if (ALU32_HAD_OVERFLOW) \
     SignalExceptionIntegerOverflow (); \
-  (ANS) = ALU32_OVERFLOW_RESULT
+  (ANS) = (signed32) ALU32_OVERFLOW_RESULT
 
 
 #define ALU64_END(ANS) \
@@ -838,6 +838,24 @@ struct sim_state {
    run-time errors in the simulator. */
 #define SimulatorFault      (0xFFFFFFFF)
 
+/* The following break instructions are reserved for use by the
+   simulator.  The first is used to halt the simulation.  The second
+   is used by gdb for break-points.  NOTE: Care must be taken, since 
+   this value may be used in later revisions of the MIPS ISA. */
+#define HALT_INSTRUCTION_MASK  (0x03FFFFC0)
+
+#define HALT_INSTRUCTION       (0x03ff000d)
+#define HALT_INSTRUCTION2      (0x0000ffcd)
+
+/* start-sanitize-sky */
+#define HALT_INSTRUCTION_PASS    (0x03fffc0d)
+#define HALT_INSTRUCTION_FAIL    (0x03ffffcd)
+/* end-sanitize-sky */
+
+#define BREAKPOINT_INSTRUCTION  (0x0005000d)
+#define BREAKPOINT_INSTRUCTION2 (0x0000014d)
+
+
 void signal_exception (SIM_DESC sd, sim_cpu *cpu, address_word cia, int exception, ...);
 #define SignalException(exc,instruction)     signal_exception (SD, CPU, cia, (exc), (instruction))
 #define SignalExceptionInterrupt()           signal_exception (SD, CPU, cia, Interrupt)