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+/* Copyright (C) 1992 Free Software Foundation, Inc.
+   Contributed by Brendan Kehoe (brendan@cs.widener.edu).
+   Also hacked by Ian Lance Taylor (ian@airs.com).
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sysdep.h>
+
+/* This function saves all the registers, calls the
+   user function, and then executes a sigreturn system call.  The
+   sigreturn call wants the address of a sigcontext structure.  This
+   is all hideously system dependent and, for all intents and
+   purposes, undocumented.
+
+   When we enter here, a3 holds the user's signal handler.  We are
+   supposed to fill in the context given in a2, and then pass it and
+   the first two arguments to the user's function.  If the user's
+   function returns, we execute a sigreturn system call.
+
+   The sc_onstack, sc_mask and sc_pc elements of the context are
+   already set by the kernel.  For some reason we don't have to save
+   the floating point state or the coprocessor state; the kernel may
+   have saved them for us, or it doesn't use them.  */
+
+.set noat
+ENTRY (__handler)
+#if 0
+	/* Store zero and the asm temp reg.  */
+	sw $0, 12(a2)
+	sw AT, 16(a2)
+
+	/* Put v1 in sc_regs[3].  */
+	sw v1, 24(a2)
+
+	/* Save the caller saved registers in sc_regs[8..15].  */
+	sw t0, 44(a2)
+	sw t1, 48(a2)
+	sw t2, 52(a2)
+	sw t3, 56(a2)
+	sw t4, 60(a2)
+	sw t5, 64(a2)
+	sw t6, 68(a2)
+	sw t7, 72(a2)
+
+	/* Save the callee saved registers in sc_regs[16..23].  */
+	sw s0, 76(a2)
+	sw s1, 80(a2)
+	sw s2, 84(a2)
+	sw s3, 88(a2)
+	sw s4, 92(a2)
+	sw s5, 96(a2)
+	sw s6, 100(a2)
+	sw s7, 104(a2)
+
+	/* Save the code generator registers in sc_regs[24] & sc_regs[25].  */
+	sw t8, 108(a2)
+	sw t9, 112(a2)
+
+	/* Save the kernel temp regs in sc_regs[26] & sc_regs[27]. */
+	sw k0, 116(a2)
+	sw k1, 120(a2)
+
+	/* Save the global pointer in sc_regs[28].  */
+	sw gp, 124(a2)
+
+	/* ... and also the return address in sc_regs[31].  */
+	sw ra, 136(a2)
+
+	/* Note: we don't save the stack pointer in sc_regs[29];
+	   instead, we use the one that was already there.  */
+#if 0
+	sw sp, 128(a2)
+#endif
+
+	/* Save the floating pointer in sc_regs[30].  */
+	sw fp, 132(a2)
+
+	/* Save the mul/div stuff in sc_mdlo and sc_mdhi.  */
+	mflo t0
+	sw t0, 140(a2)
+	mfhi t0
+	sw t0, 144(a2)
+
+#endif
+	/* Move the stack up six.  This will save the context.  */
+	addu sp, sp, -24
+	sw a2, 16(sp)
+
+	/* Call their handler with the signal, code, and context; note
+	   this will clobber the context.  */
+	.set noreorder
+	jal ra, a3
+	nop
+	.set reorder
+
+	/* When we come back, restore the context and pass it right
+	   on into sigreturn().  */
+	lw a0, 16(sp)
+
+	/* Do a sigreturn syscall; this doesn't return.  */
+	li v0, SYS_sigreturn
+	syscall
+	nop