preparation for switch-based threads

2 files changed, 107 insertions, 0 deletions

diff --git a/lib/libc_r/arch/i386/uthread_machdep.c b/lib/libc_r/arch/i386/uthread_machdep.c
new file mode 100644
index 00000000000..6535e2f73d8
--- /dev/null
+++ b/lib/libc_r/arch/i386/uthread_machdep.c
@@ -0,0 +1,80 @@
+/*	 $OpenBSD: uthread_machdep.c,v 1.1 2000/09/25 01:16:40 d Exp $	*/
+/* David Leonard, <d@csee.uq.edu.au>. Public domain. */
+
+/*
+ * Machine-dependent thread state functions for OpenBSD/sparc.
+ */
+
+#include <machine/param.h>
+#include <pthread.h>
+#include "pthread_private.h"
+
+struct frame {
+	int	fr_gs;
+	int	fr_fs;
+	int	fr_es;
+	int	fr_ds;
+
+	int	fr_edi;
+	int	fr_esi;
+	int	fr_ebp;
+	int	fr_esp;
+	int	fr_ebx;
+	int	fr_edx;
+	int	fr_ecx;
+	int	fr_eax;
+
+	int	fr_eip;
+	int	fr_cs;		/* XXX unreachable? */
+};
+
+#define copyreg(reg, lval) \
+	__asm__("mov %%" #reg ", %0" : "=g"(lval))
+
+/*
+ * Given a stack and an entry function, initialise a state
+ * structure that can be later switched to.
+ */
+void
+_thread_machdep_init(statep, base, len, entry)
+        struct _machdep_state* statep;
+        void *base;
+        int len;
+        void (*entry)(void);
+{
+	struct frame *f;
+
+	/* Locate the initial frame, aligned at the top of the stack */
+	f = (struct frame *)(((int)base + len - sizeof *f) & ~ALIGNBYTES);
+
+	/* Set up initial frame */
+	f->fr_esp = (int)&f->fr_edi;
+	copyreg(cs, f->fr_cs);
+	copyreg(ds, f->fr_ds);
+	copyreg(es, f->fr_es);
+	copyreg(fs, f->fr_fs);
+	copyreg(gs, f->fr_gs);
+	f->fr_ebp = (int)-1;
+	f->fr_eip = (int)entry;
+
+	statep->esp = (int)f;
+}
+
+void
+_thread_machdep_save_float_state(ms)
+	struct _machdep_state *ms;
+{
+	char *fdata = (char *)&ms->fpreg;
+
+	__asm__("fsave %0"::"m" (*fdata));
+}
+
+void
+_thread_machdep_restore_float_state(ms)
+	struct _machdep_state *ms;
+{
+	char *fdata = (char *)&ms->fpreg;
+
+	__asm__("frstor %0"::"m" (*fdata));
+}
+
diff --git a/lib/libc_r/arch/i386/uthread_machdep_asm.S b/lib/libc_r/arch/i386/uthread_machdep_asm.S
new file mode 100644
index 00000000000..06652fd210f
--- /dev/null
+++ b/lib/libc_r/arch/i386/uthread_machdep_asm.S
@@ -0,0 +1,27 @@
+/*	$OpenBSD: uthread_machdep_asm.S,v 1.1 2000/09/25 01:16:40 d Exp $	*/
+/* David Leonard, <d@csee.uq.edu.au>. Public domain. */
+
+#include <machine/asm.h>
+
+/*
+ * Switch stacks
+ */
+
+/* void _thread_machdep_switch(new, oldsave); */
+ENTRY(_thread_machdep_switch)
+	pushal		/* pushl %eax,%ecx,%edx,%ebx,%esp,%ebp,%esi,%edi */
+	pushl	%ds
+	pushl	%es
+	pushl	%fs
+	pushl	%gs
+#define DISTANCE	((8+1+1+1+1)*4)
+	movl	(DISTANCE+8)(%esp), %eax	/* %eax = arg2  */
+	movl	%esp, 0(%eax)			/* *arg2 = %esp */
+	movl	(DISTANCE+4)(%esp), %eax	/* %eax = arg1  */
+	movl	0(%eax), %esp			/* %esp = *arg1 */
+	popl	%gs
+	popl	%fs
+	popl	%es
+	popl	%ds
+	popal		/* popl %edi,%esi,%ebp,%esp,%ebx,%edx,%ecx,%eax */
+	ret