added tests as prepared by oliver

test/ref/incr.c

@@ -0,0 +1,51 @@
+/*
+  !!DESCRIPTION!! increment/decrement
+  !!ORIGIN!!      LCC 4.1 Testsuite
+  !!LICENCE!!     own, freely distributeable for non-profit. read CPYRIGHT.LCC
+*/
+
+#include <stdio.h>
+
+int main(void)
+{
+    printf("disassemble this program to check the generated code.\n");
+    return 0;
+}
+
+memchar() {
+	char x, *p;
+
+	&x, &p;
+	x = *p++;
+	x = *++p;
+	x = *p--;
+	x = *--p;
+}
+
+memint() {
+	int x, *p;
+
+	&x, &p;
+	x = *p++;
+	x = *++p;
+	x = *p--;
+	x = *--p;
+}
+
+regchar() {
+	register char x, *p;
+
+	x = *p++;
+	x = *++p;
+	x = *p--;
+	x = *--p;
+}
+
+regint() {
+	register int x, *p;
+
+	x = *p++;
+	x = *++p;
+	x = *p--;
+	x = *--p;
+}