Assembly routine that takes an entry point, new stack pointer address

and six extra arguments.  Sets up the stack pointer with the arguments
in the right registers/stack positions and calls the entry point.

sys/arch/pmax/stand/lib/startprog.S

@@ -0,0 +1,33 @@
+/*
+ * startprog(entry, stack, argc, argv, prom_magic, prom_ptr, bi_magic, bi_ptr);
+ *
+ * load new stack pointer, then call
+ *  entry(argc, argv, prom_magic, prom_ptr, bi_magic, bi_ptr);
+ */
+
+#include <mips/asm.h>
+
+LEAF(startprog)
+        subu    sp,sp,32
+	addu	t0,a1,-CALLFRAME_SIZ	# new stack value
+	move	t1,a0
+	move	a0,a2
+	move	a1,a3
+
+	lw	a2,48(sp)		# load everything from old stack we need
+	lw	a3,52(sp)
+	lw	v0,56(sp)
+	lw	v1,60(sp)
+
+	move	sp,t0			# new stack pointer
+	sw	ra,24(sp)
+
+	sw	v0,16(sp)
+	sw	v1,20(sp)
+	jal	ra,t1
+	nop				# BDslot
+
+	lw	ra,24(sp)		# should not get back here!
+	j	ra
+	addu	sp,sp,32
+END(startprog)