blob: a8ba3bd3d4d8cc545eaab2c62584ba4234efe15f [file] [log] [blame]
 /* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright (C) 1999-2000 Hewlett-Packard Co * Copyright (C) 1999-2000 David Mosberger-Tang * * 64-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.goodreads.com/book/show/2019887.Ia_64_and_Elementary_Functions) */ #include #include #ifdef MODULO # define OP mod #else # define OP div #endif #ifdef UNSIGNED # define SGN u # 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 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,di3)) GLOBAL_ENTRY(NAME) .regstk 2,0,0,0 // Transfer inputs to FP registers. setf.sig f8 = in0 setf.sig f9 = in1 ;; // Convert the inputs to FP, to avoid FP software-assist faults. INT_TO_FP(f8, f8) INT_TO_FP(f9, f9) ;; frcpa.s1 f11, p6 = f8, f9 // y0 = frcpa(b) ;; (p6) fmpy.s1 f7 = f8, f11 // q0 = a*y0 (p6) fnma.s1 f6 = f9, f11, f1 // e0 = -b*y0 + 1 ;; (p6) fma.s1 f10 = f7, f6, f7 // q1 = q0*e0 + q0 (p6) fmpy.s1 f7 = f6, f6 // e1 = e0*e0 ;; #ifdef MODULO sub in1 = r0, in1 // in1 = -b #endif (p6) fma.s1 f10 = f10, f7, f10 // q2 = q1*e1 + q1 (p6) fma.s1 f6 = f11, f6, f11 // y1 = y0*e0 + y0 ;; (p6) fma.s1 f6 = f6, f7, f6 // y2 = y1*e1 + y1 (p6) fnma.s1 f7 = f9, f10, f8 // r = -b*q2 + a ;; #ifdef MODULO setf.sig f8 = in0 // f8 = a setf.sig f9 = in1 // f9 = -b #endif (p6) fma.s1 f11 = f7, f6, f10 // q3 = r*y2 + q2 ;; FP_TO_INT(f11, f11) // q = trunc(q3) ;; #ifdef MODULO xma.l f11 = f11, f9, f8 // r = q*(-b) + a ;; #endif getf.sig r8 = f11 // transfer result to result register br.ret.sptk.many rp END(NAME) EXPORT_SYMBOL(NAME)