Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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| 18 | | THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA |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 | |
| 40 | FZERO: .long 00000000 |
| 41 | | |
| 42 | | FMOVECR |
| 43 | | |
| 44 | .global smovcr |
| 45 | smovcr: |
| 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 |
| 61 | Z_VAL: |
| 62 | fmoves FZERO,%fp0 |
| 63 | rts |
| 64 | PI_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 |
| 69 | PI_RZRM: |
| 70 | leal PIRZRM,%a0 |rmode is rz or rm, load PIRZRM in a0 |
| 71 | bra set_finx |
| 72 | PI_RN: |
| 73 | leal PIRN,%a0 |rmode is rn, load PIRN in a0 |
| 74 | bra set_finx |
| 75 | PI_RP: |
| 76 | leal PIRP,%a0 |rmode is rp, load PIRP in a0 |
| 77 | bra set_finx |
| 78 | SM_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 |
| 84 | SM_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 |
| 89 | SM_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 |
| 94 | SM_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 |
| 99 | BG_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 |
| 105 | BG_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 |
| 112 | BG_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 |
| 119 | BG_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 |
| 126 | set_finx: |
| 127 | orl #inx2a_mask,USER_FPSR(%a6) |set inex2/ainex |
| 128 | no_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 | | |
| 142 | not_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) |
| 158 | fin_fcr: |
| 159 | fmovemx (%a0),%fp0-%fp0 |
| 160 | rts |
| 161 | |
| 162 | |end |