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+/* 32 and 64-bit millicode, original author Hewlett-Packard
+ adapted for gcc by Paul Bame <bame@debian.org>
+ and Alan Modra <alan@linuxcare.com.au>.
+
+ Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
+
+ This file is part of GCC and is released under the terms of
+ of the GNU General Public License as published by the Free Software
+ Foundation; either version 2, or (at your option) any later version.
+ See the file COPYING in the top-level GCC source directory for a copy
+ of the license. */
+
+#include "milli.h"
+
+#ifdef L_divI
+/* ROUTINES: $$divI, $$divoI
+
+ Single precision divide for signed binary integers.
+
+ The quotient is truncated towards zero.
+ The sign of the quotient is the XOR of the signs of the dividend and
+ divisor.
+ Divide by zero is trapped.
+ Divide of -2**31 by -1 is trapped for $$divoI but not for $$divI.
+
+ INPUT REGISTERS:
+ . arg0 == dividend
+ . arg1 == divisor
+ . mrp == return pc
+ . sr0 == return space when called externally
+
+ OUTPUT REGISTERS:
+ . arg0 = undefined
+ . arg1 = undefined
+ . ret1 = quotient
+
+ OTHER REGISTERS AFFECTED:
+ . r1 = undefined
+
+ SIDE EFFECTS:
+ . Causes a trap under the following conditions:
+ . divisor is zero (traps with ADDIT,= 0,25,0)
+ . dividend==-2**31 and divisor==-1 and routine is $$divoI
+ . (traps with ADDO 26,25,0)
+ . Changes memory at the following places:
+ . NONE
+
+ PERMISSIBLE CONTEXT:
+ . Unwindable.
+ . Suitable for internal or external millicode.
+ . Assumes the special millicode register conventions.
+
+ DISCUSSION:
+ . Branchs to other millicode routines using BE
+ . $$div_# for # being 2,3,4,5,6,7,8,9,10,12,14,15
+ .
+ . For selected divisors, calls a divide by constant routine written by
+ . Karl Pettis. Eligible divisors are 1..15 excluding 11 and 13.
+ .
+ . The only overflow case is -2**31 divided by -1.
+ . Both routines return -2**31 but only $$divoI traps. */
+
+RDEFINE(temp,r1)
+RDEFINE(retreg,ret1) /* r29 */
+RDEFINE(temp1,arg0)
+ SUBSPA_MILLI_DIV
+ ATTR_MILLI
+ .import $$divI_2,millicode
+ .import $$divI_3,millicode
+ .import $$divI_4,millicode
+ .import $$divI_5,millicode
+ .import $$divI_6,millicode
+ .import $$divI_7,millicode
+ .import $$divI_8,millicode
+ .import $$divI_9,millicode
+ .import $$divI_10,millicode
+ .import $$divI_12,millicode
+ .import $$divI_14,millicode
+ .import $$divI_15,millicode
+ .export $$divI,millicode
+ .export $$divoI,millicode
+ .proc
+ .callinfo millicode
+ .entry
+GSYM($$divoI)
+ comib,=,n -1,arg1,LREF(negative1) /* when divisor == -1 */
+GSYM($$divI)
+ ldo -1(arg1),temp /* is there at most one bit set ? */
+ and,<> arg1,temp,r0 /* if not, don't use power of 2 divide */
+ addi,> 0,arg1,r0 /* if divisor > 0, use power of 2 divide */
+ b,n LREF(neg_denom)
+LSYM(pow2)
+ addi,>= 0,arg0,retreg /* if numerator is negative, add the */
+ add arg0,temp,retreg /* (denominaotr -1) to correct for shifts */
+ extru,= arg1,15,16,temp /* test denominator with 0xffff0000 */
+ extrs retreg,15,16,retreg /* retreg = retreg >> 16 */
+ or arg1,temp,arg1 /* arg1 = arg1 | (arg1 >> 16) */
+ ldi 0xcc,temp1 /* setup 0xcc in temp1 */
+ extru,= arg1,23,8,temp /* test denominator with 0xff00 */
+ extrs retreg,23,24,retreg /* retreg = retreg >> 8 */
+ or arg1,temp,arg1 /* arg1 = arg1 | (arg1 >> 8) */
+ ldi 0xaa,temp /* setup 0xaa in temp */
+ extru,= arg1,27,4,r0 /* test denominator with 0xf0 */
+ extrs retreg,27,28,retreg /* retreg = retreg >> 4 */
+ and,= arg1,temp1,r0 /* test denominator with 0xcc */
+ extrs retreg,29,30,retreg /* retreg = retreg >> 2 */
+ and,= arg1,temp,r0 /* test denominator with 0xaa */
+ extrs retreg,30,31,retreg /* retreg = retreg >> 1 */
+ MILLIRETN
+LSYM(neg_denom)
+ addi,< 0,arg1,r0 /* if arg1 >= 0, it's not power of 2 */
+ b,n LREF(regular_seq)
+ sub r0,arg1,temp /* make denominator positive */
+ comb,=,n arg1,temp,LREF(regular_seq) /* test against 0x80000000 and 0 */
+ ldo -1(temp),retreg /* is there at most one bit set ? */
+ and,= temp,retreg,r0 /* if so, the denominator is power of 2 */
+ b,n LREF(regular_seq)
+ sub r0,arg0,retreg /* negate numerator */
+ comb,=,n arg0,retreg,LREF(regular_seq) /* test against 0x80000000 */
+ copy retreg,arg0 /* set up arg0, arg1 and temp */
+ copy temp,arg1 /* before branching to pow2 */
+ b LREF(pow2)
+ ldo -1(arg1),temp
+LSYM(regular_seq)
+ comib,>>=,n 15,arg1,LREF(small_divisor)
+ add,>= 0,arg0,retreg /* move dividend, if retreg < 0, */
+LSYM(normal)
+ subi 0,retreg,retreg /* make it positive */
+ sub 0,arg1,temp /* clear carry, */
+ /* negate the divisor */
+ ds 0,temp,0 /* set V-bit to the comple- */
+ /* ment of the divisor sign */
+ add retreg,retreg,retreg /* shift msb bit into carry */
+ ds r0,arg1,temp /* 1st divide step, if no carry */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 2nd divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 3rd divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 4th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 5th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 6th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 7th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 8th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 9th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 10th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 11th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 12th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 13th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 14th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 15th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 16th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 17th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 18th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 19th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 20th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 21st divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 22nd divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 23rd divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 24th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 25th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 26th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 27th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 28th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 29th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 30th divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 31st divide step */
+ addc retreg,retreg,retreg /* shift retreg with/into carry */
+ ds temp,arg1,temp /* 32nd divide step, */
+ addc retreg,retreg,retreg /* shift last retreg bit into retreg */
+ xor,>= arg0,arg1,0 /* get correct sign of quotient */
+ sub 0,retreg,retreg /* based on operand signs */
+ MILLIRETN
+ nop
+
+LSYM(small_divisor)
+
+#if defined(CONFIG_64BIT)
+/* Clear the upper 32 bits of the arg1 register. We are working with */
+/* small divisors (and 32-bit integers) We must not be mislead */
+/* by "1" bits left in the upper 32 bits. */
+ depd %r0,31,32,%r25
+#endif
+ blr,n arg1,r0
+ nop
+/* table for divisor == 0,1, ... ,15 */
+ addit,= 0,arg1,r0 /* trap if divisor == 0 */
+ nop
+ MILLIRET /* divisor == 1 */
+ copy arg0,retreg
+ MILLI_BEN($$divI_2) /* divisor == 2 */
+ nop
+ MILLI_BEN($$divI_3) /* divisor == 3 */
+ nop
+ MILLI_BEN($$divI_4) /* divisor == 4 */
+ nop
+ MILLI_BEN($$divI_5) /* divisor == 5 */
+ nop
+ MILLI_BEN($$divI_6) /* divisor == 6 */
+ nop
+ MILLI_BEN($$divI_7) /* divisor == 7 */
+ nop
+ MILLI_BEN($$divI_8) /* divisor == 8 */
+ nop
+ MILLI_BEN($$divI_9) /* divisor == 9 */
+ nop
+ MILLI_BEN($$divI_10) /* divisor == 10 */
+ nop
+ b LREF(normal) /* divisor == 11 */
+ add,>= 0,arg0,retreg
+ MILLI_BEN($$divI_12) /* divisor == 12 */
+ nop
+ b LREF(normal) /* divisor == 13 */
+ add,>= 0,arg0,retreg
+ MILLI_BEN($$divI_14) /* divisor == 14 */
+ nop
+ MILLI_BEN($$divI_15) /* divisor == 15 */
+ nop
+
+LSYM(negative1)
+ sub 0,arg0,retreg /* result is negation of dividend */
+ MILLIRET
+ addo arg0,arg1,r0 /* trap iff dividend==0x80000000 && divisor==-1 */
+ .exit
+ .procend
+ .end
+#endif