X-Git-Url: https://git.gag.com/?p=fw%2Fsdcc;a=blobdiff_plain;f=debugger%2Fmcs51%2Fcmd.c;h=cd038fffea32bcf9665469ffdfa2ba1671a79186;hp=4cae0c91c5ec1284ef09a7437c965a3744e58e3b;hb=HEAD;hpb=31264d72ca126a7ad645192145c94daf4d72e2a7

diff --git a/debugger/mcs51/cmd.c b/debugger/mcs51/cmd.c
index 4cae0c91..cd038fff 100644
--- a/debugger/mcs51/cmd.c
+++ b/debugger/mcs51/cmd.c
@@ -1053,7 +1053,16 @@ static int stack_change(unsigned addr)
 	}
 }
 
-static int pc_change(unsigned addr, unsigned addrs[2])
+static void
+do_indent(int indent);
+
+#if 1
+#define DPC(x)
+#else
+#define DPC(x)	do { do_indent(indent); printf x; } while (0);
+#endif
+
+static int pc_change(unsigned addr, unsigned addrs[2], int indent)
 {
 	unsigned char insn;
 	unsigned new_addr;
@@ -1072,6 +1081,7 @@ static int pc_change(unsigned addr, unsigned addrs[2])
 	if (insn == LJMP_addr16) {
 		addrs[0] = ((simGetValue(addr+1, 'C', 1) << 8) |
 			  (simGetValue(addr+2, 'C', 1)));
+		DPC(("0x%04x LJMP 0x%04x\n", addr, addrs[0]));
 		return 1;
 	}
 	
@@ -1080,6 +1090,7 @@ static int pc_change(unsigned addr, unsigned addrs[2])
 		unsigned char	direct = simGetValue(addr+1,'C', 1);
 
 		addrs[0] = ((addr + 2) & 0xf800) | ((insn & 0xe0) << 3) | direct;
+		DPC(("0x%04x AJMP 0x%04x\n", addr, addrs[0]));
 		return 1;
 	}
 
@@ -1089,23 +1100,44 @@ static int pc_change(unsigned addr, unsigned addrs[2])
 	delta = (signed char) simGetValue(addr+len-1, 'C', 1);
 	new_addr = (addr + len) + delta;
 	
-	if (insn == SJMP_rel) {
+	if (insn == SJMP_rel || (addr + len) == new_addr) {
 		addrs[0] = new_addr;
+		DPC(("0x%04x SJMP 0x%04x\n", addr, addrs[0]));
 		return 1;
 	}
+	addrs[0] = (addr + len) & 0xffff;
+	addrs[1] = new_addr & 0xffff;
 
-	addrs[0] = addr + len;
-	addrs[1] = new_addr;
+	DPC(("0x%04x SJMP 0x%04x 0x%04x\n", addr, addrs[0], addrs[1]));
 	return 2;
 }
 
-#define SEARCH_FAILED	0x8000
+#define SEARCH_LOOP	0x8000
+#define SEARCH_EXPIRED	0x8001
+
+#define MAX_STACK_BRANCH_TRACE	8192
+static unsigned stack_branch_trace[MAX_STACK_BRANCH_TRACE];
 
 static int
-stack_depth(unsigned pc, int search)
+been_here(unsigned pc, int ntrace)
+{
+	int t;
+	
+	for (t = 0; t < ntrace; t++)
+		if (stack_branch_trace[t] == pc)
+			return 1;
+	return 0;
+}
+
+#define MAX_SEARCH	100
+
+#define indent (MAX_SEARCH - search)
+
+static int
+stack_depth(unsigned pc, int search, int ntrace)
 {
 	unsigned new_pc[2];
-	unsigned max_pc = pc;
+	int d[2];
 	int n;
 	int s;
 	int change;
@@ -1113,35 +1145,62 @@ stack_depth(unsigned pc, int search)
 	change = 0;
 	for (;;) {
 		change += stack_change(pc);
-		n = pc_change(pc, new_pc);
+		n = pc_change(pc, new_pc, MAX_SEARCH - search);
 		if (n == 0)
 			return change;
 		if (n != 1)
 			break;
+		if (new_pc[0] <= pc) {
+			if (been_here(pc, ntrace)) {
+				DPC(("0x%04x loop 1\n", pc));
+				return SEARCH_LOOP;
+			}
+			stack_branch_trace[ntrace++] = pc;
+		}
 		pc = new_pc[0];
-		/* detect infinite loop */
-		if (pc == max_pc)
-			return change;
-		if (pc > max_pc)
-			max_pc = pc;
 	}
 	
-	if (search == 0)
-		return SEARCH_FAILED;
+	if (search == 0) {
+		DPC(("0x%04x max depth\n", pc));
+		return SEARCH_EXPIRED;
+	}
 	
+	if (been_here(pc, ntrace))
+	{
+		DPC(("0x%04x loop 2\n", pc));
+		return SEARCH_LOOP;
+	}
+	stack_branch_trace[ntrace++] = pc;
+
 	for (s = 0; s < search - 1; s++) {
-		int d;
-		int i;
-		d = SEARCH_FAILED;
-		for (i = 0; i < n; i++) {
-			d = stack_depth(new_pc[i], search-1);
-			if (d != SEARCH_FAILED)
+		int i, j, d;
+		
+		i = 0;
+		while (i < n) {
+			d = stack_depth(new_pc[i], search-1, ntrace);
+			if (d == SEARCH_LOOP) {
+				for (j = i; j < n-1; j++)
+					new_pc[j] = new_pc[j+1];
+				n--;
+				continue;
+			}
+			if (d != SEARCH_EXPIRED) {
+				DPC(("success %d\n", d + change));
 				return d + change;
+			}
+			i++;
+		}
+		if (n == 0) {
+			DPC(("0x%04x loop 3\n", pc));
+			return SEARCH_LOOP;
 		}
 	}
-	return SEARCH_FAILED;
+	DPC(("search expired\n"));
+	return SEARCH_EXPIRED;
 }
 
+#undef indent
+
 unsigned int
 stack_start(void)
 {
@@ -1162,10 +1221,11 @@ frameStart(unsigned int *bpp, unsigned int *pcp)
 
 	pc = simGetPC();
 	sp = simGetValue(0x81,'I',1);
-	depth = stack_depth(pc, 100);
-	bp = sp + depth;
-	if (bp < stack_start())
-		return 0;
+	depth = stack_depth(pc, MAX_SEARCH, 0);
+	if (depth == SEARCH_LOOP || depth == SEARCH_EXPIRED)
+		bp = 0;
+	else
+		bp = sp + depth;
 	*bpp = bp;
 	*pcp = pc;
 	return 1;
@@ -1182,8 +1242,13 @@ frameNext(unsigned int *bpp, unsigned int *pcp)
 	if (bp < stack_start())
 		return 0;
 	pc = simGetValue(bp - 1, 'B', 2);
-	depth = stack_depth(pc, 100);
-	bp = bp - 2 + depth;
+	if (pc == 0xffff)
+		return 0;
+	depth = stack_depth(pc, MAX_SEARCH, 0);
+	if (depth == SEARCH_LOOP || depth == SEARCH_EXPIRED)
+		bp = 0;
+	else
+		bp = bp - 2 + depth;
 	*bpp = bp;
 	*pcp = pc;
 	return 1;