break

dos/main.k

@@ -22,6 +22,7 @@ main:
 ;
 exit:
     enter
+    break
 
     mov ax0, .msg
     call print

pc/Makefile

@@ -5,7 +5,8 @@ all: k.exe
 
 src = instrs/instrs.c decd.c main.c regs.c dump.c \
       instrs/jumps.c except.c disd.c mem.c instrs/logic.c \
-      instrs/stack.c instrs/super.c instrs/arith.c log.c
+      instrs/stack.c instrs/super.c instrs/arith.c log.c \
+      instrs/debug.c
 
 obj = $(patsubst %.c,%.o,$(src))
 

pc/except.c

@@ -16,6 +16,8 @@ void _except(ctx_t *ctx, int code, char *fmt, ...)
     log("\n");
 
     dumpregs(ctx);
+    log("\n");
+
     dumpfwstack(ctx);
 
     if (ctx->mp)

pc/instrs/INSTRS

@@ -160,9 +160,6 @@ xchg m m
 lea r m
 lea m m
 
-# get code segment
-gcs r m
-
 #
 # Stack manipulation instructions
 #
@@ -199,8 +196,17 @@ popf
 cli
 sti
 
+#
+# Misc. instructions
+#
+
 # Prints a character on the screen
 prn r
 prn i
 prn m
 
+#
+# Debugging instructions
+#
+break
+

pc/instrs/debug.c

@@ -0,0 +1,15 @@
+// The OS/K Team licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#include "instrs.h"
+#include "arch_i.h"
+
+IMPL_START_0(break)
+{
+    log("\nExecuting BREAK INSTR\n");
+    dumpregs(ctx);
+
+    while ((getchar() != '\n'));
+    log("Resuming execution\n");
+}
+IMPL_END;

pc/regs.c

@@ -88,7 +88,7 @@ void dumpregs(ctx_t *ctx)
         log("%s%s=0x%-16lX ", r->name,
             (strlen(r->name) == 2 ? "=" : ""), r->val);
     }
-    log("\nrip=0x%-16lX rbp=0x%-16lX rsp=0x%-16lX flg=0x%-16lX\n\n",
+    log("\nrip=0x%-16lX rbp=0x%-16lX rsp=0x%-16lX flg=0x%-16lX\n",
         ctx->r[RIP].val,
         ctx->r[RBP].val,
         ctx->r[RSP].val,