1| 2| smovecr.sa 3.1 12/10/90 3| 4| The entry point sMOVECR returns the constant at the 5| offset given in the instruction field. 6| 7| Input: An offset in the instruction word. 8| 9| Output: The constant rounded to the user's rounding 10| mode unchecked for overflow. 11| 12| Modified: fp0. 13| 14| 15| Copyright (C) Motorola, Inc. 1990 16| All Rights Reserved 17| 18| THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA 19| The copyright notice above does not evidence any 20| actual or intended publication of such source code. 21 22|SMOVECR idnt 2,1 | Motorola 040 Floating Point Software Package 23 24 |section 8 25 26 .include "fpsp.h" 27 28 |xref nrm_set 29 |xref round 30 |xref PIRN 31 |xref PIRZRM 32 |xref PIRP 33 |xref SMALRN 34 |xref SMALRZRM 35 |xref SMALRP 36 |xref BIGRN 37 |xref BIGRZRM 38 |xref BIGRP 39 40FZERO: .long 00000000 41| 42| FMOVECR 43| 44 .global smovcr 45smovcr: 46 bfextu CMDREG1B(%a6){#9:#7},%d0 |get offset 47 bfextu USER_FPCR(%a6){#26:#2},%d1 |get rmode 48| 49| check range of offset 50| 51 tstb %d0 |if zero, offset is to pi 52 beqs PI_TBL |it is pi 53 cmpib #0x0a,%d0 |check range $01 - $0a 54 bles Z_VAL |if in this range, return zero 55 cmpib #0x0e,%d0 |check range $0b - $0e 56 bles SM_TBL |valid constants in this range 57 cmpib #0x2f,%d0 |check range $10 - $2f 58 bles Z_VAL |if in this range, return zero 59 cmpib #0x3f,%d0 |check range $30 - $3f 60 ble BG_TBL |valid constants in this range 61Z_VAL: 62 fmoves FZERO,%fp0 63 rts 64PI_TBL: 65 tstb %d1 |offset is zero, check for rmode 66 beqs PI_RN |if zero, rn mode 67 cmpib #0x3,%d1 |check for rp 68 beqs PI_RP |if 3, rp mode 69PI_RZRM: 70 leal PIRZRM,%a0 |rmode is rz or rm, load PIRZRM in a0 71 bra set_finx 72PI_RN: 73 leal PIRN,%a0 |rmode is rn, load PIRN in a0 74 bra set_finx 75PI_RP: 76 leal PIRP,%a0 |rmode is rp, load PIRP in a0 77 bra set_finx 78SM_TBL: 79 subil #0xb,%d0 |make offset in 0 - 4 range 80 tstb %d1 |check for rmode 81 beqs SM_RN |if zero, rn mode 82 cmpib #0x3,%d1 |check for rp 83 beqs SM_RP |if 3, rp mode 84SM_RZRM: 85 leal SMALRZRM,%a0 |rmode is rz or rm, load SMRZRM in a0 86 cmpib #0x2,%d0 |check if result is inex 87 ble set_finx |if 0 - 2, it is inexact 88 bra no_finx |if 3, it is exact 89SM_RN: 90 leal SMALRN,%a0 |rmode is rn, load SMRN in a0 91 cmpib #0x2,%d0 |check if result is inex 92 ble set_finx |if 0 - 2, it is inexact 93 bra no_finx |if 3, it is exact 94SM_RP: 95 leal SMALRP,%a0 |rmode is rp, load SMRP in a0 96 cmpib #0x2,%d0 |check if result is inex 97 ble set_finx |if 0 - 2, it is inexact 98 bra no_finx |if 3, it is exact 99BG_TBL: 100 subil #0x30,%d0 |make offset in 0 - f range 101 tstb %d1 |check for rmode 102 beqs BG_RN |if zero, rn mode 103 cmpib #0x3,%d1 |check for rp 104 beqs BG_RP |if 3, rp mode 105BG_RZRM: 106 leal BIGRZRM,%a0 |rmode is rz or rm, load BGRZRM in a0 107 cmpib #0x1,%d0 |check if result is inex 108 ble set_finx |if 0 - 1, it is inexact 109 cmpib #0x7,%d0 |second check 110 ble no_finx |if 0 - 7, it is exact 111 bra set_finx |if 8 - f, it is inexact 112BG_RN: 113 leal BIGRN,%a0 |rmode is rn, load BGRN in a0 114 cmpib #0x1,%d0 |check if result is inex 115 ble set_finx |if 0 - 1, it is inexact 116 cmpib #0x7,%d0 |second check 117 ble no_finx |if 0 - 7, it is exact 118 bra set_finx |if 8 - f, it is inexact 119BG_RP: 120 leal BIGRP,%a0 |rmode is rp, load SMRP in a0 121 cmpib #0x1,%d0 |check if result is inex 122 ble set_finx |if 0 - 1, it is inexact 123 cmpib #0x7,%d0 |second check 124 ble no_finx |if 0 - 7, it is exact 125| bra set_finx ;if 8 - f, it is inexact 126set_finx: 127 orl #inx2a_mask,USER_FPSR(%a6) |set inex2/ainex 128no_finx: 129 mulul #12,%d0 |use offset to point into tables 130 movel %d1,L_SCR1(%a6) |load mode for round call 131 bfextu USER_FPCR(%a6){#24:#2},%d1 |get precision 132 tstl %d1 |check if extended precision 133| 134| Precision is extended 135| 136 bnes not_ext |if extended, do not call round 137 fmovemx (%a0,%d0),%fp0-%fp0 |return result in fp0 138 rts 139| 140| Precision is single or double 141| 142not_ext: 143 swap %d1 |rnd prec in upper word of d1 144 addl L_SCR1(%a6),%d1 |merge rmode in low word of d1 145 movel (%a0,%d0),FP_SCR1(%a6) |load first word to temp storage 146 movel 4(%a0,%d0),FP_SCR1+4(%a6) |load second word 147 movel 8(%a0,%d0),FP_SCR1+8(%a6) |load third word 148 clrl %d0 |clear g,r,s 149 lea FP_SCR1(%a6),%a0 150 btstb #sign_bit,LOCAL_EX(%a0) 151 sne LOCAL_SGN(%a0) |convert to internal ext. format 152 153 bsr round |go round the mantissa 154 155 bfclr LOCAL_SGN(%a0){#0:#8} |convert back to IEEE ext format 156 beqs fin_fcr 157 bsetb #sign_bit,LOCAL_EX(%a0) 158fin_fcr: 159 fmovemx (%a0),%fp0-%fp0 160 rts 161 162 |end 163