$NetBSD: patch-ci,v 1.1 2000/06/19 15:56:36 pooka Exp $

--- /dev/null   Thu Jan  1 00:00:00 1970
+++ config/unix/sun_netbsd/rswitch.c    Thu Jun  8 22:14:54 2000
@@ -0,0 +1,39 @@
+/*
+ * coswitch for Sun-4 Sparc.
+ * 
+ * Compile this with 'cc -c rswitch.c'.  Do not use cc -O.
+ */
+
+/* #include <sys/asm_linkage.h> */
+/*#include <sys/trap.h>*/
+
+int coswitch(old_cs, new_cs, first)
+int *old_cs, *new_cs;
+int first;
+{
+   asm("ta     0x03");                 /* ST_FLUSH_WINDOWS in trap.h     */
+   asm("ld     [%fp+0x44], %o0");      /* load old_cs into %o0           */
+   asm("st     %sp,[%o0]");            /* Save user stack pointer        */
+   asm("st     %fp,[%o0+0x4]");        /* Save frame pointer             */
+   asm("st     %i7,[%o0+0x8]");        /* Save return address            */
+
+   if (first == 0) {                   /* this is the first activation   */
+      asm("ld  [%fp+0x48], %o0");      /* load new_cs into %o0           */
+      asm("ld  [%o0], %o1");           /* load %o1 from cstate[0]        */
+
+      /* Decrement new stack pointer value before loading it into sp.    */
+      /* The top 64 bytes of the stack are reserved for the kernel, to    */
+      /* save the 8 local and 8 in registers into, on context switches,   */
+      /* interrupts, traps, etc.                                         */
+
+      asm("save  %o1,-96, %sp");       /* load %sp from %o1              */
+      new_context(0,0);
+      syserr("new_context() returned in coswitch");
+
+   } else {
+      asm("ld  [%fp+0x48], %o0");      /* load new_cs into %o0           */
+      asm("ld  [%o0+0x4],%fp");        /* Load frame pointer             */
+      asm("ld  [%o0+0x8],%i7");        /* Load return address            */
+      asm("ld  [%o0],%sp");            /* Load user stack pointer        */
+   }
+}