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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 | | | x_fline.sa 3.3 1/10/91 | | fpsp_fline --- FPSP handler for fline exception | | First determine if the exception is one of the unimplemented | floating point instructions. If so, let fpsp_unimp handle it. | Next, determine if the instruction is an fmovecr with a non-zero | <ea> field. If so, handle here and return. Otherwise, it | must be a real F-line exception. | | Copyright (C) Motorola, Inc. 1990 | All Rights Reserved | | THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA | The copyright notice above does not evidence any | actual or intended publication of such source code. X_FLINE: |idnt 2,1 | Motorola 040 Floating Point Software Package |section 8 .include "fpsp.h" |xref real_fline |xref fpsp_unimp |xref uni_2 |xref mem_read |xref fpsp_fmt_error .global fpsp_fline fpsp_fline: | | check for unimplemented vector first. Use EXC_VEC-4 because | the equate is valid only after a 'link a6' has pushed one more | long onto the stack. | cmpw #UNIMP_VEC,EXC_VEC-4(%a7) beql fpsp_unimp | | fmovecr with non-zero <ea> handling here | subl #4,%a7 |4 accounts for 2-word difference | ;between six word frame (unimp) and | ;four word frame link %a6,#-LOCAL_SIZE fsave -(%a7) moveml %d0-%d1/%a0-%a1,USER_DA(%a6) moveal EXC_PC+4(%a6),%a0 |get address of fline instruction leal L_SCR1(%a6),%a1 |use L_SCR1 as scratch movel #4,%d0 addl #4,%a6 |to offset the sub.l #4,a7 above so that | ;a6 can point correctly to the stack frame | ;before branching to mem_read bsrl mem_read subl #4,%a6 movel L_SCR1(%a6),%d0 |d0 contains the fline and command word bfextu %d0{#4:#3},%d1 |extract coprocessor id cmpib #1,%d1 |check if cpid=1 bne not_mvcr |exit if not bfextu %d0{#16:#6},%d1 cmpib #0x17,%d1 |check if it is an FMOVECR encoding bne not_mvcr | ;if an FMOVECR instruction, fix stack | ;and go to FPSP_UNIMP fix_stack: cmpib #VER_40,(%a7) |test for orig unimp frame bnes ck_rev subl #UNIMP_40_SIZE-4,%a7 |emulate an orig fsave moveb #VER_40,(%a7) moveb #UNIMP_40_SIZE-4,1(%a7) clrw 2(%a7) bras fix_con ck_rev: cmpib #VER_41,(%a7) |test for rev unimp frame bnel fpsp_fmt_error |if not $40 or $41, exit with error subl #UNIMP_41_SIZE-4,%a7 |emulate a rev fsave moveb #VER_41,(%a7) moveb #UNIMP_41_SIZE-4,1(%a7) clrw 2(%a7) fix_con: movew EXC_SR+4(%a6),EXC_SR(%a6) |move stacked sr to new position movel EXC_PC+4(%a6),EXC_PC(%a6) |move stacked pc to new position fmovel EXC_PC(%a6),%FPIAR |point FPIAR to fline inst movel #4,%d1 addl %d1,EXC_PC(%a6) |increment stacked pc value to next inst movew #0x202c,EXC_VEC(%a6) |reformat vector to unimp clrl EXC_EA(%a6) |clear the EXC_EA field movew %d0,CMDREG1B(%a6) |move the lower word into CMDREG1B clrl E_BYTE(%a6) bsetb #UFLAG,T_BYTE(%a6) moveml USER_DA(%a6),%d0-%d1/%a0-%a1 |restore data registers bral uni_2 not_mvcr: moveml USER_DA(%a6),%d0-%d1/%a0-%a1 |restore data registers frestore (%a7)+ unlk %a6 addl #4,%a7 bral real_fline |end |