forth: fix dumb bug in (?br)

inc (hl) is 8 bit, inc (hl) is 8 bit, inc (hl) is 8 bit. Now I hope
I'll remember...

emul/emul.c

@@ -7,6 +7,7 @@ They all run on the same kind of virtual machine: A z80 CPU, 64K of RAM/ROM.
 #include "emul.h"
 
 static Machine m;
+static ushort traceval = 0;
 
 static uint8_t io_read(int unused, uint16_t addr)
 {
@@ -92,6 +93,15 @@ void emul_loop()
     while (emul_step());
 }
 
+void emul_trace(ushort addr)
+{
+    ushort newval = m.mem[addr+1] << 8 | m.mem[addr];
+    if (newval != traceval) {
+        traceval = newval;
+        fprintf(stderr, "trace: %04x PC: %04x\n", traceval, m.cpu.PC);
+    }
+}
+
 void emul_printdebug()
 {
     fprintf(stderr, "Min SP: %04x\n", m.minsp);

emul/emul.h

@@ -30,4 +30,5 @@ Machine* emul_init();
 bool emul_step();
 bool emul_steps(unsigned int steps);
 void emul_loop();
+void emul_trace(ushort addr);
 void emul_printdebug();

forth/forth.asm

@@ -683,12 +683,13 @@ CBR:
 	or	l
 	jp	z, BR+2		; False, branch
 	; True, skip next 2 bytes and don't branch
-	ld	hl, IP
-	inc	(hl)
-	inc	(hl)
+	ld	hl, (IP)
+	inc	hl
+	inc	hl
+	ld	(IP), hl
 	jp	next
 
-.fill 18
+.fill 15
 
 	.db	","
 	.dw	$-CBR