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+/* Copyright (C) 1996 Free Software Foundation, Inc.
+   Contributed by David Mosberger (davidm@cs.arizona.edu).
+
+This file is part of the GNU C Library.
+
+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.  */
+
+/* The current Alpha chips don't provide hardware for integer
+division.  The C compiler expects the functions
+
+	__divqu: 64-bit unsigned long divide
+	__remqu: 64-bit unsigned long remainder
+	__divqs/__remqs: signed 64-bit
+	__divlu/__remlu: unsigned 32-bit
+	__divls/__remls: signed 32-bit
+
+These are not normal C functions: instead of the normal calling
+sequence, these expect their arguments in registers t10 and t11, and
+return the result in t12 (aka pv). Registers AT and v0 may be
+clobbered (assembly temporary), anything else must be saved.  */
+
+#ifdef __linux__
+# include <alpha/regdef.h>
+# include <asm/gentrap.h>
+# include <asm/pal.h>
+#else
+# include <regdef.h>
+# include <machine/pal.h>
+#endif
+
+#ifdef DEBUG
+# define arg1		a0
+# define arg2		a1
+# define result		v0
+# define mask		t0
+# define tmp0		t1
+# define tmp1		t2
+# define sign		t3
+# define retaddr	ra
+#else
+# define arg1		t10
+# define arg2		t11
+# define result		t12
+# define mask		v0
+# define tmp0		t0
+# define tmp1		t1
+# define sign		t2
+# define retaddr	t9
+#endif
+
+# define divisor	arg2
+#if IS_REM
+# define dividend	result
+# define quotient	arg1
+# define GETDIVIDEND	bis arg1,zero,dividend
+#else
+# define dividend	arg1
+# define quotient	result
+# define GETDIVIDEND
+#endif
+
+#if SIZE == 8
+# define LONGIFYarg1	GETDIVIDEND
+# define LONGIFYarg2
+#else
+# if SIGNED
+#  define LONGIFYarg1	addl	arg1,zero,dividend
+#  define LONGIFYarg2	addl	arg2,zero,divisor
+# else
+#  define LONGIFYarg1	zapnot	arg1,0x0f,dividend
+#  define LONGIFYarg2	zapnot	arg2,0x0f,divisor
+# endif
+#endif
+
+#if SIGNED
+# define SETSIGN(sign,reg,tmp)	subq zero,reg,tmp; cmovlt sign,tmp,reg
+# if IS_REM
+#  define GETSIGN(x,y,s)	bis	x,zero,s
+# else
+#  define GETSIGN(x,y,s)	xor	x,y,s
+# endif
+#else
+# define SETSIGN(sign,reg,tmp)
+# define GETSIGN(x,y,s)
+#endif
+
+	.set noreorder
+	.set noat
+
+	.ent FUNC_NAME
+	.globl FUNC_NAME
+
+	.align 5
+FUNC_NAME:
+#	define FRAME_SIZE	0x30
+	.frame	sp,FRAME_SIZE,ra,0
+	lda	sp,-FRAME_SIZE(sp)
+	.prologue 1
+	stq	arg1,0x00(sp)
+	LONGIFYarg1
+	stq	arg2,0x08(sp)
+	LONGIFYarg2
+	stq	mask,0x10(sp)
+	bis	zero,1,mask
+	stq	tmp0,0x18(sp)
+	bis	zero,zero,quotient
+	stq	tmp1,0x20(sp)
+	beq	divisor,divbyzero
+	stq	sign,0x28(sp)
+	GETSIGN(dividend,divisor,sign)
+#if SIGNED
+	subq	zero,dividend,tmp0
+	subq	zero,divisor,tmp1
+	cmovlt	dividend,tmp0,dividend
+	cmovlt	divisor,tmp1,divisor
+#endif
+	/*
+	 * Shift divisor left until either bit 63 is set or until it
+	 * is at least as big as the dividend:
+	 */
+	.align	3
+1:	cmpule	dividend,divisor,AT
+	blt	divisor,2f
+	blbs	AT,2f
+	addq	mask,mask,mask
+	addq	divisor,divisor,divisor
+	br	1b
+
+	.align	3
+2:	addq	mask,quotient,tmp0
+	cmpule	divisor,dividend,AT
+	subq	dividend,divisor,tmp1
+	srl	divisor,1,divisor
+	srl	mask,1,mask
+	cmovlbs	AT,tmp0,quotient
+	cmovlbs	AT,tmp1,dividend
+	bne	mask,2b
+
+	ldq	arg1,0x00(sp)
+	SETSIGN(sign,result,tmp0)
+done:	ldq	arg2,0x08(sp)
+	ldq	mask,0x10(sp)
+	ldq	tmp0,0x18(sp)
+	ldq	tmp1,0x20(sp)
+	ldq	sign,0x28(sp)
+	lda	sp,FRAME_SIZE(sp)
+	ret	zero,(retaddr),0
+
+divbyzero:
+	lda	a0,GEN_INTDIV(zero)
+	call_pal PAL_gentrap
+	bis	zero,zero,result	/* if trap returns, return 0 */
+	ldq	arg1,0x00(sp)
+	br	done
+
+	.end FUNC_NAME