gbdb: optimize breakpoints and add runto

src/apps/gbdb.c

@@ -19,13 +19,14 @@
 #include "common/tri.h"
 
 #define INPUT_MAX_LEN 512
-#define MAX_BREAKPTS 4 /* Should be plenty for anyone */
+#define MAX_BREAKPTS 2 /* Should be plenty for anyone */
 #define MAX_RAM_LEN (1 << 20) /* Up to 8Mb Cartridge */
 #define UNMAP_BOOTROM_ADDR 0xff50
 
 typedef void (gbdb_cmd)(char *arg_string);
 
 static bool cpu_at_breakpoint(void);
+static void breakpoint_addr_hit(uint16_t id);
 
 static uint8_t ram[MAX_RAM_LEN];
 static const char prompt[] = "gbdb >";
@@ -208,6 +209,7 @@ static void step(char *arg_list)
 	if (init_steps + steps <= cpu.metrics.retired_instrs) {
 		gb_log("CPU stopped after %" PRId64 " instructions\n", steps);
 	} else if (cpu_at_breakpoint()) {
+		breakpoint_addr_hit(cpu.pc);
 		gb_log("Breakpoint hit\n");
 	} else if (cpu.halted) {
 		gb_log("CPU halted\n");
@@ -438,8 +440,7 @@ static void quit(char *arg_list)
 	exit(0);
 }
 
-static void run(char *arg_list)
-{
+static void do_run(void) {
 	paused = 0;
 	signal(SIGINT, break_execution_handler);
 	while(!cpu.halted && !cpu_at_breakpoint() && !paused) {
@@ -451,43 +452,129 @@ static void run(char *arg_list)
 	} else if (paused) {
 		gb_log("Interrupted.\n");
 	} else {
-		gb_log("Breakpoint hit\n");
+	  breakpoint_addr_hit(cpu.pc);
+	  gb_log("Breakpoint hit\n");
 	}
 }
 
-static struct {
-	uint16_t addr;
-	bool active;
+static void run(char *arg_list)
+{
+  do_run();
+}
+
+static struct breakpoint {
+  uint16_t addr;
+  int id;
+  bool temp;
 } breakpoints[MAX_BREAKPTS];
 
+static int num_breakpoints = 0;
+
+static struct breakpoint *get_breakpoint(int id)
+{
+  int i;
+
+  for (i = 0; i < num_breakpoints; i++) {
+	if (breakpoints[i].id == id) {
+	  return &breakpoints[i];
+	}
+  }
+
+  return NULL;
+}
+
+static int do_set_breakpoint(uint16_t addr, bool temp)
+{
+  static int id = 0;
+  if (num_breakpoints < ARRAY_SIZE(breakpoints)) {
+	breakpoints[num_breakpoints].addr = addr;
+	breakpoints[num_breakpoints].id = id++;
+	breakpoints[num_breakpoints].temp = temp;
+	num_breakpoints++;
+  } else {
+	printf("maximum number of breakpoints reached\n");
+  }
+}
+
 static void set_breakpoint(char *arg_string)
 {
 	uint16_t addr, i;
 	char *token = strtok(arg_string, " ");
-
+	
 	if (token == NULL) {
 		printf("usage: breakpoint add <addr>\n");
 		return;
 	}
 
 	addr = parse_val(token);
+	do_set_breakpoint(addr, false);
+}
 
-	for (i = 0; i < ARRAY_SIZE(breakpoints); i++) {
-		if (breakpoints[i].active == false) {
-			breakpoints[i].addr = addr;
-			breakpoints[i].active = true;
-			return;
-		}
+static void runto(char *arg_string)
+{
+  uint16_t addr, i, rc;
+	char *token = strtok(arg_string, " ");
+	
+	if (token == NULL) {
+		printf("usage: runto <addr>\n");
+		return;
 	}
 
-	printf("maximum number of breakpoints reached\n");
+	addr = parse_val(token);
+	rc = do_set_breakpoint(addr, true);
+	if (rc < 0) {
+	  printf("failed to set breakpoint\n");
+	  return;
+	}
+
+	do_run();
+}
+
+static int do_delete_breakpoint(int id)
+{
+  struct breakpoint *bkpt = get_breakpoint(id);
+  int index;
+  
+  if (bkpt == NULL) {
+	return -1;
+  }
+
+  index = bkpt - breakpoints;
+  memmove(&breakpoints[index], &breakpoints[index + 1],
+		  num_breakpoints - index - 1);
+  num_breakpoints--;
+
+  return 0;
+}
+
+static void breakpoint_addr_hit(uint16_t addr)
+{
+  struct breakpoint *bkpt = NULL;
+  int i;
+
+  for (i = 0; i < num_breakpoints; i++) {
+	if (breakpoints[i].addr == addr) {
+	  bkpt= &breakpoints[i];
+	  break;
+	}
+  }
+  
+
+  if (bkpt == NULL) {
+	printf("No breakpoint found at addr=%d\n", addr);
+	return;
+  }
+
+  if (bkpt->temp) {
+	do_delete_breakpoint(bkpt->id);
+  }
 }
 
 static void delete_breakpoint(char *arg_string)
 {
-	int bkpt;
 	char *token = strtok(arg_string, " ");
-
+	int rc, bkpt;
+	
 	if (token == NULL) {
 		printf("usage: breakpoint rm <bkpt num>\n");
 		return;
@@ -495,27 +582,21 @@ static void delete_breakpoint(char *arg_string)
 
 	bkpt = parse_val(token);
 
-	if (bkpt < 0 || bkpt >= ARRAY_SIZE(breakpoints) || !breakpoints[bkpt].active) {
-		printf("%d is not a valid breakpoint number\n", bkpt);
-		return;
+	rc = do_delete_breakpoint(bkpt);
+	if (rc < 0) {
+	  printf("%d is not a valid breakpoint number\n", bkpt);
 	}
-
-	breakpoints[bkpt].active = false;
 }
 
 static void display_breakpoints(char *arg_string)
 {
-	bool found1 = false;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(breakpoints); i++) {
-		if (breakpoints[i].active) {
-			printf("#%d: 0x%04x\n", i, breakpoints[i].addr);
-			found1 = true;
-		}
-	}
-
-	if(!found1) {
+	if (num_breakpoints) {
+	  for (i = 0; i < num_breakpoints; i++) {
+		printf("#%d: 0x%04x\n", breakpoints[i].id, breakpoints[i].addr);
+	  }
+	} else {
 		printf("No breakpoints set\n");
 	}
 }
@@ -565,8 +646,8 @@ static void breakpoint(char *arg_list)
 static bool breakpoint_is_at_addr(uint16_t addr) {
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(breakpoints); i++) {
-		if (breakpoints[i].active && addr == breakpoints[i].addr) {
+	for (i = 0; i < num_breakpoints; i++) {
+		if (breakpoints[i].addr == addr) {
 			return true;
 		}
 	}
@@ -576,7 +657,7 @@ static bool breakpoint_is_at_addr(uint16_t addr) {
 
 static bool cpu_at_breakpoint(void)
 {
-	return breakpoint_is_at_addr(lr35902_get_reg_16(&cpu, LR35902_REG_PC));
+	return breakpoint_is_at_addr(cpu.pc);
 }
 
 static void process_cmd(const char *cmd_str, struct tri *commands)
@@ -689,6 +770,7 @@ int main(int argc, char **argv)
 	tri_add_string(&commands, "help", help);
 	tri_add_string(&commands, "?", help);
 	tri_add_string(&commands, "breakpoint", breakpoint);
+	tri_add_string(&commands, "runto", runto);
 	tri_add_string(&commands, "reset", init);
 	tri_add_string(&commands, "assert", assert);
 	tri_add_string(&commands, "set", set);