Make avr_where() available for use in debugging. It provides a decoded

string representing the PC's value.  Also fix mangled line indentification
strings found in use.  They occurred when multiple lines had one address.

Author: ga

simavr/sim/sim_avr.h

@@ -503,6 +503,12 @@ uint64_t
 avr_get_time_stamp(
 		avr_t * avr );
 
+/* This function returns a text string describing where in flash the AVR's
+ * PC is pointing.  It requires the CONFIG_SIMAVR_TRACE option.
+ */
+
+const char *avr_where(avr_t *avr);
+
 #ifdef __cplusplus
 };
 #endif

simavr/sim/sim_core.c

@@ -71,7 +71,7 @@ int dont_trace(const char * name)
 
 static int donttrace;
 
-static const char *where(avr_t *avr)
+const char *avr_where(avr_t *avr)
 {
 	avr_flashaddr_t  pc;
 	const char      *s;
@@ -100,8 +100,8 @@ static const char *where(avr_t *avr)
 	return "";
 }
 
-#define STATE(_f, argsf ...)	if (avr->trace) {				\
-	const char *symn = where(avr);							\
+#define STATE(_f, argsf ...)	if (avr->trace) {			\
+	const char *symn = avr_where(avr);						\
 	if (symn)												\
 		printf("%04x: %-25s " _f, avr->pc, symn, ## argsf);	\
 }
@@ -161,6 +161,8 @@ void crash(avr_t* avr)
 	avr_sadly_crashed(avr, 0);
 
 }
+
+const char *avr_where(avr_t *avr) { return ""; }
 #endif
 
 static inline uint16_t

simavr/sim/sim_dwarf.c

@@ -306,6 +306,7 @@ int avr_read_dwarf(avr_t *avr, const char *filename)
         CHECK("dwarf_siblingof_b");
 
 #if CONFIG_SIMAVR_TRACE
+        Dwarf_Addr  prev_addr = -1;
         const char *last_symbol = NULL;
         int         i, prev_line;
 
@@ -322,9 +323,10 @@ int avr_read_dwarf(avr_t *avr, const char *filename)
             CHECK("dwarf_lineno");
             rv = dwarf_lineaddr(ctx.lines[i], &addr, &err);
             CHECK("dwarf_lineaddr");
-            if (prev_line == lineno)
+            if (prev_line == lineno || prev_addr == addr)
                 continue;	// Ignore duplicates
             prev_line = lineno;
+            prev_addr = addr;
             if (addr == 0) // Inlined?
                 continue;
             ep = avr->trace_data->codeline + (addr >> 1);