x_fline.sa revision 1.1.1.1
1 * MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP 2 * M68000 Hi-Performance Microprocessor Division 3 * M68040 Software Package 4 * 5 * M68040 Software Package Copyright (c) 1993, 1994 Motorola Inc. 6 * All rights reserved. 7 * 8 * THE SOFTWARE is provided on an "AS IS" basis and without warranty. 9 * To the maximum extent permitted by applicable law, 10 * MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED, 11 * INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A 12 * PARTICULAR PURPOSE and any warranty against infringement with 13 * regard to the SOFTWARE (INCLUDING ANY MODIFIED VERSIONS THEREOF) 14 * and any accompanying written materials. 15 * 16 * To the maximum extent permitted by applicable law, 17 * IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER 18 * (INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS 19 * PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR 20 * OTHER PECUNIARY LOSS) ARISING OF THE USE OR INABILITY TO USE THE 21 * SOFTWARE. Motorola assumes no responsibility for the maintenance 22 * and support of the SOFTWARE. 23 * 24 * You are hereby granted a copyright license to use, modify, and 25 * distribute the SOFTWARE so long as this entire notice is retained 26 * without alteration in any modified and/or redistributed versions, 27 * and that such modified versions are clearly identified as such. 28 * No licenses are granted by implication, estoppel or otherwise 29 * under any patents or trademarks of Motorola, Inc. 30 31 * 32 * x_fline.sa 3.3 1/10/91 33 * 34 * fpsp_fline --- FPSP handler for fline exception 35 * 36 * First determine if the exception is one of the unimplemented 37 * floating point instructions. If so, let fpsp_unimp handle it. 38 * Next, determine if the instruction is an fmovecr with a non-zero 39 * <ea> field. If so, handle here and return. Otherwise, it 40 * must be a real F-line exception. 41 * 42 43 X_FLINE IDNT 2,1 Motorola 040 Floating Point Software Package 44 45 section 8 46 47 include fpsp.h 48 49 xref real_fline 50 xref fpsp_unimp 51 xref uni_2 52 xref mem_read 53 xref fpsp_fmt_error 54 55 xdef fpsp_fline 56 fpsp_fline: 57 * 58 * check for unimplemented vector first. Use EXC_VEC-4 because 59 * the equate is valid only after a 'link a6' has pushed one more 60 * long onto the stack. 61 * 62 cmp.w #UNIMP_VEC,EXC_VEC-4(a7) 63 beq.l fpsp_unimp 64 65 * 66 * fmovecr with non-zero <ea> handling here 67 * 68 sub.l #4,a7 ;4 accounts for 2-word difference 69 * ;between six word frame (unimp) and 70 * ;four word frame 71 link a6,#-LOCAL_SIZE 72 fsave -(a7) 73 movem.l d0-d1/a0-a1,USER_DA(a6) 74 movea.l EXC_PC+4(a6),a0 ;get address of fline instruction 75 lea.l L_SCR1(a6),a1 ;use L_SCR1 as scratch 76 move.l #4,d0 77 add.l #4,a6 ;to offset the sub.l #4,a7 above so that 78 * ;a6 can point correctly to the stack frame 79 * ;before branching to mem_read 80 bsr.l mem_read 81 sub.l #4,a6 82 move.l L_SCR1(a6),d0 ;d0 contains the fline and command word 83 bfextu d0{4:3},d1 ;extract coprocessor id 84 cmpi.b #1,d1 ;check if cpid=1 85 bne.w not_mvcr ;exit if not 86 bfextu d0{16:6},d1 87 cmpi.b #$17,d1 ;check if it is an FMOVECR encoding 88 bne.w not_mvcr 89 * ;if an FMOVECR instruction, fix stack 90 * ;and go to FPSP_UNIMP 91 fix_stack: 92 cmpi.b #VER_40,(a7) ;test for orig unimp frame 93 bne.b ck_rev 94 sub.l #UNIMP_40_SIZE-4,a7 ;emulate an orig fsave 95 move.b #VER_40,(a7) 96 move.b #UNIMP_40_SIZE-4,1(a7) 97 clr.w 2(a7) 98 bra.b fix_con 99 ck_rev: 100 cmpi.b #VER_41,(a7) ;test for rev unimp frame 101 bne.l fpsp_fmt_error ;if not $40 or $41, exit with error 102 sub.l #UNIMP_41_SIZE-4,a7 ;emulate a rev fsave 103 move.b #VER_41,(a7) 104 move.b #UNIMP_41_SIZE-4,1(a7) 105 clr.w 2(a7) 106 fix_con: 107 move.w EXC_SR+4(a6),EXC_SR(a6) ;move stacked sr to new position 108 move.l EXC_PC+4(a6),EXC_PC(a6) ;move stacked pc to new position 109 fmove.l EXC_PC(a6),FPIAR ;point FPIAR to fline inst 110 move.l #4,d1 111 add.l d1,EXC_PC(a6) ;increment stacked pc value to next inst 112 move.w #$202c,EXC_VEC(a6) ;reformat vector to unimp 113 clr.l EXC_EA(a6) ;clear the EXC_EA field 114 move.w d0,CMDREG1B(a6) ;move the lower word into CMDREG1B 115 clr.l E_BYTE(a6) 116 bset.b #UFLAG,T_BYTE(a6) 117 movem.l USER_DA(a6),d0-d1/a0-a1 ;restore data registers 118 bra.l uni_2 119 120 not_mvcr: 121 movem.l USER_DA(a6),d0-d1/a0-a1 ;restore data registers 122 frestore (a7)+ 123 unlk a6 124 add.l #4,a7 125 bra.l real_fline 126 127 end 128
Indexes created Mon Oct 27 20:09:55 GMT 2025