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Diffstat (limited to 'lib/libc/alpha/gen/divrem.m4')
| -rw-r--r-- | lib/libc/alpha/gen/divrem.m4 | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/lib/libc/alpha/gen/divrem.m4 b/lib/libc/alpha/gen/divrem.m4 deleted file mode 100644 index 6afa2e1..0000000 --- a/lib/libc/alpha/gen/divrem.m4 +++ /dev/null @@ -1,198 +0,0 @@ -/* $NetBSD: divrem.m4,v 1.7 1996/10/17 03:08:04 cgd Exp $ */ -/* $FreeBSD$ */ - -/* - * Copyright (c) 1994, 1995 Carnegie-Mellon University. - * All rights reserved. - * - * Author: Chris G. Demetriou - * - * Permission to use, copy, modify and distribute this software and - * its documentation is hereby granted, provided that both the copyright - * notice and this permission notice appear in all copies of the - * software, derivative works or modified versions, and any portions - * thereof, and that both notices appear in supporting documentation. - * - * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" - * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND - * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. - * - * Carnegie Mellon requests users of this software to return to - * - * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU - * School of Computer Science - * Carnegie Mellon University - * Pittsburgh PA 15213-3890 - * - * any improvements or extensions that they make and grant Carnegie the - * rights to redistribute these changes. - */ - -/* - * Division and remainder. - * - * The use of m4 is modeled after the sparc code, but the algorithm is - * simple binary long division. - * - * Note that the loops could probably benefit from unrolling. - */ - -/* - * M4 Parameters - * NAME name of function to generate - * OP OP=div: t10 / t11 -> t12; OP=rem: t10 % t11 -> t12 - * S S=true: signed; S=false: unsigned - * WORDSIZE total number of bits - */ - -define(A, `t10') -define(B, `t11') -define(RESULT, `t12') - -define(BIT, `t0') -define(I, `t1') -define(CC, `t2') -define(T_0, `t3') -ifelse(S, `true', `define(NEG, `t4')') - -#include <machine/asm.h> - -NESTED(NAME, 0, 0, t9, 0, 0) /* Get the right ra */ - lda sp, -64(sp) - stq BIT, 0(sp) - stq I, 8(sp) - stq CC, 16(sp) - stq T_0, 24(sp) -ifelse(S, `true', -` stq NEG, 32(sp)') - stq A, 40(sp) - stq B, 48(sp) - mov zero, RESULT /* Initialize result to zero */ - -ifelse(S, `true', -` - /* Compute sign of result. If either is negative, this is easy. */ - or A, B, NEG /* not the sign, but... */ - srl NEG, WORDSIZE - 1, NEG /* rather, or of high bits */ - blbc NEG, Ldoit /* neither negative? do it! */ - -ifelse(OP, `div', -` xor A, B, NEG /* THIS is the sign! */ -', ` mov A, NEG /* sign follows A. */ -') - srl NEG, WORDSIZE - 1, NEG /* make negation the low bit. */ - - srl A, WORDSIZE - 1, I /* is A negative? */ - blbc I, LnegB /* no. */ - /* A is negative; flip it. */ -ifelse(WORDSIZE, `32', ` - /* top 32 bits may be random junk */ - zap A, 0xf0, A -') - subq zero, A, A - srl B, WORDSIZE - 1, I /* is B negative? */ - blbc I, Ldoit /* no. */ -LnegB: - /* B is definitely negative, no matter how we got here. */ -ifelse(WORDSIZE, `32', ` - /* top 32 bits may be random junk */ - zap B, 0xf0, B -') - subq zero, B, B -Ldoit: -') -ifelse(WORDSIZE, `32', ` - /* - * Clear the top 32 bits of each operand, as they may - * sign extension (if negated above), or random junk. - */ - zap A, 0xf0, A - zap B, 0xf0, B -') - - /* kill the special cases. */ - beq B, Ldotrap /* division by zero! */ - - cmpult A, B, CC /* A < B? */ - /* RESULT is already zero, from above. A is untouched. */ - bne CC, Lret_result - - cmpeq A, B, CC /* A == B? */ - cmovne CC, 1, RESULT - cmovne CC, zero, A - bne CC, Lret_result - - /* - * Find out how many bits of zeros are at the beginning of the divisor. - */ -LBbits: - ldiq T_0, 1 /* I = 0; BIT = 1<<WORDSIZE-1 */ - mov zero, I - sll T_0, WORDSIZE-1, BIT -LBloop: - and B, BIT, CC /* if bit in B is set, done. */ - bne CC, LAbits - addq I, 1, I /* increment I, shift bit */ - srl BIT, 1, BIT - cmplt I, WORDSIZE-1, CC /* if I leaves one bit, done. */ - bne CC, LBloop - -LAbits: - beq I, Ldodiv /* If I = 0, divide now. */ - ldiq T_0, 1 /* BIT = 1<<WORDSIZE-1 */ - sll T_0, WORDSIZE-1, BIT - -LAloop: - and A, BIT, CC /* if bit in A is set, done. */ - bne CC, Ldodiv - subq I, 1, I /* decrement I, shift bit */ - srl BIT, 1, BIT - bne I, LAloop /* If I != 0, loop again */ - -Ldodiv: - sll B, I, B /* B <<= i */ - ldiq T_0, 1 - sll T_0, I, BIT - -Ldivloop: - cmpult A, B, CC - or RESULT, BIT, T_0 - cmoveq CC, T_0, RESULT - subq A, B, T_0 - cmoveq CC, T_0, A - srl BIT, 1, BIT - srl B, 1, B - beq A, Lret_result - bne BIT, Ldivloop - -Lret_result: -ifelse(OP, `div', -`', ` mov A, RESULT -') -ifelse(S, `true', -` - /* Check to see if we should negate it. */ - subq zero, RESULT, T_0 - cmovlbs NEG, T_0, RESULT -') - - ldq BIT, 0(sp) - ldq I, 8(sp) - ldq CC, 16(sp) - ldq T_0, 24(sp) -ifelse(S, `true', -` ldq NEG, 32(sp)') - ldq A, 40(sp) - ldq B, 48(sp) - lda sp, 64(sp) - ret zero, (t9), 1 - -Ldotrap: - ldiq a0, -2 /* This is the signal to SIGFPE! */ - call_pal PAL_gentrap -ifelse(OP, `div', -`', ` mov zero, A /* so that zero will be returned */ -') - br zero, Lret_result - -END(NAME) |
