You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
84 lines
2.0 KiB
84 lines
2.0 KiB
20 years ago
|
/*
|
||
|
|
* Copyright (C) 2000 Hewlett-Packard Co
|
||
|
|
* Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
|
||
|
|
*
|
||
|
|
* 32-bit integer division.
|
||
|
|
*
|
||
|
|
* This code is based on the application note entitled "Divide, Square Root
|
||
|
|
* and Remainder Algorithms for the IA-64 Architecture". This document
|
||
|
|
* is available as Intel document number 248725-002 or via the web at
|
||
|
|
* http://developer.intel.com/software/opensource/numerics/
|
||
|
|
*
|
||
|
|
* For more details on the theory behind these algorithms, see "IA-64
|
||
|
|
* and Elementary Functions" by Peter Markstein; HP Professional Books
|
||
|
|
* (http://www.hp.com/go/retailbooks/)
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <asm/asmmacro.h>
|
||
|
|
|
||
|
|
#ifdef MODULO
|
||
|
|
# define OP mod
|
||
|
|
#else
|
||
|
|
# define OP div
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef UNSIGNED
|
||
|
|
# define SGN u
|
||
|
|
# define EXTEND zxt4
|
||
|
|
# define INT_TO_FP(a,b) fcvt.xuf.s1 a=b
|
||
|
|
# define FP_TO_INT(a,b) fcvt.fxu.trunc.s1 a=b
|
||
|
|
#else
|
||
|
|
# define SGN
|
||
|
|
# define EXTEND sxt4
|
||
|
|
# define INT_TO_FP(a,b) fcvt.xf a=b
|
||
|
|
# define FP_TO_INT(a,b) fcvt.fx.trunc.s1 a=b
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define PASTE1(a,b) a##b
|
||
|
|
#define PASTE(a,b) PASTE1(a,b)
|
||
|
|
#define NAME PASTE(PASTE(__,SGN),PASTE(OP,si3))
|
||
|
|
|
||
|
|
GLOBAL_ENTRY(NAME)
|
||
|
|
.regstk 2,0,0,0
|
||
|
|
// Transfer inputs to FP registers.
|
||
|
|
mov r2 = 0xffdd // r2 = -34 + 65535 (fp reg format bias)
|
||
|
|
EXTEND in0 = in0 // in0 = a
|
||
|
|
EXTEND in1 = in1 // in1 = b
|
||
|
|
;;
|
||
|
|
setf.sig f8 = in0
|
||
|
|
setf.sig f9 = in1
|
||
|
|
#ifdef MODULO
|
||
|
|
sub in1 = r0, in1 // in1 = -b
|
||
|
|
#endif
|
||
|
|
;;
|
||
|
|
// Convert the inputs to FP, to avoid FP software-assist faults.
|
||
|
|
INT_TO_FP(f8, f8)
|
||
|
|
INT_TO_FP(f9, f9)
|
||
|
|
;;
|
||
|
|
setf.exp f7 = r2 // f7 = 2^-34
|
||
|
|
frcpa.s1 f6, p6 = f8, f9 // y0 = frcpa(b)
|
||
|
|
;;
|
||
|
|
(p6) fmpy.s1 f8 = f8, f6 // q0 = a*y0
|
||
|
|
(p6) fnma.s1 f6 = f9, f6, f1 // e0 = -b*y0 + 1
|
||
|
|
;;
|
||
|
|
#ifdef MODULO
|
||
|
|
setf.sig f9 = in1 // f9 = -b
|
||
|
|
#endif
|
||
|
|
(p6) fma.s1 f8 = f6, f8, f8 // q1 = e0*q0 + q0
|
||
|
|
(p6) fma.s1 f6 = f6, f6, f7 // e1 = e0*e0 + 2^-34
|
||
|
|
;;
|
||
|
|
#ifdef MODULO
|
||
|
|
setf.sig f7 = in0
|
||
|
|
#endif
|
||
|
|
(p6) fma.s1 f6 = f6, f8, f8 // q2 = e1*q1 + q1
|
||
|
|
;;
|
||
|
|
FP_TO_INT(f6, f6) // q = trunc(q2)
|
||
|
|
;;
|
||
|
|
#ifdef MODULO
|
||
|
|
xma.l f6 = f6, f9, f7 // r = q*(-b) + a
|
||
|
|
;;
|
||
|
|
#endif
|
||
|
|
getf.sig r8 = f6 // transfer result to result register
|
||
|
|
br.ret.sptk.many rp
|
||
|
|
END(NAME)
|