| | |
| | gen_except.sa 3.7 1/16/92 |
| | |
| | gen_except --- FPSP routine to detect reportable exceptions |
| | |
| | This routine compares the exception enable byte of the |
| | user_fpcr on the stack with the exception status byte |
| | of the user_fpsr. |
| | |
| | Any routine which may report an exceptions must load |
| | the stack frame in memory with the exceptional operand(s). |
| | |
| | Priority for exceptions is: |
| | |
| | Highest: bsun |
| | snan |
| | operr |
| | ovfl |
| | unfl |
| | dz |
| | inex2 |
| | Lowest: inex1 |
| | |
| | Note: The IEEE standard specifies that inex2 is to be |
| | reported if ovfl occurs and the ovfl enable bit is not |
| | set but the inex2 enable bit is. |
| | |
| | |
| | Copyright (C) Motorola, Inc. 1990 |
| | All Rights Reserved |
| | |
| | For details on the license for this file, please see the |
| | file, README, in this same directory. |
| |
| GEN_EXCEPT: |idnt 2,1 | Motorola 040 Floating Point Software Package |
| |
| |section 8 |
| |
| #include "fpsp.h" |
| |
| |xref real_trace |
| |xref fpsp_done |
| |xref fpsp_fmt_error |
| |
| exc_tbl: |
| .long bsun_exc |
| .long commonE1 |
| .long commonE1 |
| .long ovfl_unfl |
| .long ovfl_unfl |
| .long commonE1 |
| .long commonE3 |
| .long commonE3 |
| .long no_match |
| |
| .global gen_except |
| gen_except: |
| cmpib #IDLE_SIZE-4,1(%a7) |test for idle frame |
| beq do_check |go handle idle frame |
| cmpib #UNIMP_40_SIZE-4,1(%a7) |test for orig unimp frame |
| beqs unimp_x |go handle unimp frame |
| cmpib #UNIMP_41_SIZE-4,1(%a7) |test for rev unimp frame |
| beqs unimp_x |go handle unimp frame |
| cmpib #BUSY_SIZE-4,1(%a7) |if size <> $60, fmt error |
| bnel fpsp_fmt_error |
| leal BUSY_SIZE+LOCAL_SIZE(%a7),%a1 |init a1 so fpsp.h |
| | ;equates will work |
| | Fix up the new busy frame with entries from the unimp frame |
| | |
| movel ETEMP_EX(%a6),ETEMP_EX(%a1) |copy etemp from unimp |
| movel ETEMP_HI(%a6),ETEMP_HI(%a1) |frame to busy frame |
| movel ETEMP_LO(%a6),ETEMP_LO(%a1) |
| movel CMDREG1B(%a6),CMDREG1B(%a1) |set inst in frame to unimp |
| movel CMDREG1B(%a6),%d0 |fix cmd1b to make it |
| andl #0x03c30000,%d0 |work for cmd3b |
| bfextu CMDREG1B(%a6){#13:#1},%d1 |extract bit 2 |
| lsll #5,%d1 |
| swap %d1 |
| orl %d1,%d0 |put it in the right place |
| bfextu CMDREG1B(%a6){#10:#3},%d1 |extract bit 3,4,5 |
| lsll #2,%d1 |
| swap %d1 |
| orl %d1,%d0 |put them in the right place |
| movel %d0,CMDREG3B(%a1) |in the busy frame |
| | |
| | Or in the FPSR from the emulation with the USER_FPSR on the stack. |
| | |
| fmovel %FPSR,%d0 |
| orl %d0,USER_FPSR(%a6) |
| movel USER_FPSR(%a6),FPSR_SHADOW(%a1) |set exc bits |
| orl #sx_mask,E_BYTE(%a1) |
| bra do_clean |
| |
| | |
| | Frame is an unimp frame possible resulting from an fmove <ea>,fp0 |
| | that caused an exception |
| | |
| | a1 is modified to point into the new frame allowing fpsp equates |
| | to be valid. |
| | |
| unimp_x: |
| cmpib #UNIMP_40_SIZE-4,1(%a7) |test for orig unimp frame |
| bnes test_rev |
| leal UNIMP_40_SIZE+LOCAL_SIZE(%a7),%a1 |
| bras unimp_con |
| test_rev: |
| cmpib #UNIMP_41_SIZE-4,1(%a7) |test for rev unimp frame |
| bnel fpsp_fmt_error |if not $28 or $30 |
| leal UNIMP_41_SIZE+LOCAL_SIZE(%a7),%a1 |
| |
| unimp_con: |
| | |
| | Fix up the new unimp frame with entries from the old unimp frame |
| | |
| movel CMDREG1B(%a6),CMDREG1B(%a1) |set inst in frame to unimp |
| | |
| | Or in the FPSR from the emulation with the USER_FPSR on the stack. |
| | |
| fmovel %FPSR,%d0 |
| orl %d0,USER_FPSR(%a6) |
| bra do_clean |
| |
| | |
| | Frame is idle, so check for exceptions reported through |
| | USER_FPSR and set the unimp frame accordingly. |
| | A7 must be incremented to the point before the |
| | idle fsave vector to the unimp vector. |
| | |
| |
| do_check: |
| addl #4,%a7 |point A7 back to unimp frame |
| | |
| | Or in the FPSR from the emulation with the USER_FPSR on the stack. |
| | |
| fmovel %FPSR,%d0 |
| orl %d0,USER_FPSR(%a6) |
| | |
| | On a busy frame, we must clear the nmnexc bits. |
| | |
| cmpib #BUSY_SIZE-4,1(%a7) |check frame type |
| bnes check_fr |if busy, clr nmnexc |
| clrw NMNEXC(%a6) |clr nmnexc & nmcexc |
| btstb #5,CMDREG1B(%a6) |test for fmove out |
| bnes frame_com |
| movel USER_FPSR(%a6),FPSR_SHADOW(%a6) |set exc bits |
| orl #sx_mask,E_BYTE(%a6) |
| bras frame_com |
| check_fr: |
| cmpb #UNIMP_40_SIZE-4,1(%a7) |
| beqs frame_com |
| clrw NMNEXC(%a6) |
| frame_com: |
| moveb FPCR_ENABLE(%a6),%d0 |get fpcr enable byte |
| andb FPSR_EXCEPT(%a6),%d0 |and in the fpsr exc byte |
| bfffo %d0{#24:#8},%d1 |test for first set bit |
| leal exc_tbl,%a0 |load jmp table address |
| subib #24,%d1 |normalize bit offset to 0-8 |
| movel (%a0,%d1.w*4),%a0 |load routine address based |
| | ;based on first enabled exc |
| jmp (%a0) |jump to routine |
| | |
| | Bsun is not possible in unimp or unsupp |
| | |
| bsun_exc: |
| bra do_clean |
| | |
| | The typical work to be done to the unimp frame to report an |
| | exception is to set the E1/E3 byte and clr the U flag. |
| | commonE1 does this for E1 exceptions, which are snan, |
| | operr, and dz. commonE3 does this for E3 exceptions, which |
| | are inex2 and inex1, and also clears the E1 exception bit |
| | left over from the unimp exception. |
| | |
| commonE1: |
| bsetb #E1,E_BYTE(%a6) |set E1 flag |
| bra commonE |go clean and exit |
| |
| commonE3: |
| tstb UFLG_TMP(%a6) |test flag for unsup/unimp state |
| bnes unsE3 |
| uniE3: |
| bsetb #E3,E_BYTE(%a6) |set E3 flag |
| bclrb #E1,E_BYTE(%a6) |clr E1 from unimp |
| bra commonE |
| |
| unsE3: |
| tstb RES_FLG(%a6) |
| bnes unsE3_0 |
| unsE3_1: |
| bsetb #E3,E_BYTE(%a6) |set E3 flag |
| unsE3_0: |
| bclrb #E1,E_BYTE(%a6) |clr E1 flag |
| movel CMDREG1B(%a6),%d0 |
| andl #0x03c30000,%d0 |work for cmd3b |
| bfextu CMDREG1B(%a6){#13:#1},%d1 |extract bit 2 |
| lsll #5,%d1 |
| swap %d1 |
| orl %d1,%d0 |put it in the right place |
| bfextu CMDREG1B(%a6){#10:#3},%d1 |extract bit 3,4,5 |
| lsll #2,%d1 |
| swap %d1 |
| orl %d1,%d0 |put them in the right place |
| movel %d0,CMDREG3B(%a6) |in the busy frame |
| |
| commonE: |
| bclrb #UFLAG,T_BYTE(%a6) |clr U flag from unimp |
| bra do_clean |go clean and exit |
| | |
| | No bits in the enable byte match existing exceptions. Check for |
| | the case of the ovfl exc without the ovfl enabled, but with |
| | inex2 enabled. |
| | |
| no_match: |
| btstb #inex2_bit,FPCR_ENABLE(%a6) |check for ovfl/inex2 case |
| beqs no_exc |if clear, exit |
| btstb #ovfl_bit,FPSR_EXCEPT(%a6) |now check ovfl |
| beqs no_exc |if clear, exit |
| bras ovfl_unfl |go to unfl_ovfl to determine if |
| | ;it is an unsupp or unimp exc |
| |
| | No exceptions are to be reported. If the instruction was |
| | unimplemented, no FPU restore is necessary. If it was |
| | unsupported, we must perform the restore. |
| no_exc: |
| tstb UFLG_TMP(%a6) |test flag for unsupp/unimp state |
| beqs uni_no_exc |
| uns_no_exc: |
| tstb RES_FLG(%a6) |check if frestore is needed |
| bne do_clean |if clear, no frestore needed |
| uni_no_exc: |
| moveml USER_DA(%a6),%d0-%d1/%a0-%a1 |
| fmovemx USER_FP0(%a6),%fp0-%fp3 |
| fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar |
| unlk %a6 |
| bra finish_up |
| | |
| | Unsupported Data Type Handler: |
| | Ovfl: |
| | An fmoveout that results in an overflow is reported this way. |
| | Unfl: |
| | An fmoveout that results in an underflow is reported this way. |
| | |
| | Unimplemented Instruction Handler: |
| | Ovfl: |
| | Only scosh, setox, ssinh, stwotox, and scale can set overflow in |
| | this manner. |
| | Unfl: |
| | Stwotox, setox, and scale can set underflow in this manner. |
| | Any of the other Library Routines such that f(x)=x in which |
| | x is an extended denorm can report an underflow exception. |
| | It is the responsibility of the exception-causing exception |
| | to make sure that WBTEMP is correct. |
| | |
| | The exceptional operand is in FP_SCR1. |
| | |
| ovfl_unfl: |
| tstb UFLG_TMP(%a6) |test flag for unsupp/unimp state |
| beqs ofuf_con |
| | |
| | The caller was from an unsupported data type trap. Test if the |
| | caller set CU_ONLY. If so, the exceptional operand is expected in |
| | FPTEMP, rather than WBTEMP. |
| | |
| tstb CU_ONLY(%a6) |test if inst is cu-only |
| beq unsE3 |
| | move.w #$fe,CU_SAVEPC(%a6) |
| clrb CU_SAVEPC(%a6) |
| bsetb #E1,E_BYTE(%a6) |set E1 exception flag |
| movew ETEMP_EX(%a6),FPTEMP_EX(%a6) |
| movel ETEMP_HI(%a6),FPTEMP_HI(%a6) |
| movel ETEMP_LO(%a6),FPTEMP_LO(%a6) |
| bsetb #fptemp15_bit,DTAG(%a6) |set fpte15 |
| bclrb #UFLAG,T_BYTE(%a6) |clr U flag from unimp |
| bra do_clean |go clean and exit |
| |
| ofuf_con: |
| moveb (%a7),VER_TMP(%a6) |save version number |
| cmpib #BUSY_SIZE-4,1(%a7) |check for busy frame |
| beqs busy_fr |if unimp, grow to busy |
| cmpib #VER_40,(%a7) |test for orig unimp frame |
| bnes try_41 |if not, test for rev frame |
| moveql #13,%d0 |need to zero 14 lwords |
| bras ofuf_fin |
| try_41: |
| cmpib #VER_41,(%a7) |test for rev unimp frame |
| bnel fpsp_fmt_error |if neither, exit with error |
| moveql #11,%d0 |need to zero 12 lwords |
| |
| ofuf_fin: |
| clrl (%a7) |
| loop1: |
| clrl -(%a7) |clear and dec a7 |
| dbra %d0,loop1 |
| moveb VER_TMP(%a6),(%a7) |
| moveb #BUSY_SIZE-4,1(%a7) |write busy fmt word. |
| busy_fr: |
| movel FP_SCR1(%a6),WBTEMP_EX(%a6) |write |
| movel FP_SCR1+4(%a6),WBTEMP_HI(%a6) |exceptional op to |
| movel FP_SCR1+8(%a6),WBTEMP_LO(%a6) |wbtemp |
| bsetb #E3,E_BYTE(%a6) |set E3 flag |
| bclrb #E1,E_BYTE(%a6) |make sure E1 is clear |
| bclrb #UFLAG,T_BYTE(%a6) |clr U flag |
| movel USER_FPSR(%a6),FPSR_SHADOW(%a6) |
| orl #sx_mask,E_BYTE(%a6) |
| movel CMDREG1B(%a6),%d0 |fix cmd1b to make it |
| andl #0x03c30000,%d0 |work for cmd3b |
| bfextu CMDREG1B(%a6){#13:#1},%d1 |extract bit 2 |
| lsll #5,%d1 |
| swap %d1 |
| orl %d1,%d0 |put it in the right place |
| bfextu CMDREG1B(%a6){#10:#3},%d1 |extract bit 3,4,5 |
| lsll #2,%d1 |
| swap %d1 |
| orl %d1,%d0 |put them in the right place |
| movel %d0,CMDREG3B(%a6) |in the busy frame |
| |
| | |
| | Check if the frame to be restored is busy or unimp. |
| |** NOTE *** Bug fix for errata (0d43b #3) |
| | If the frame is unimp, we must create a busy frame to |
| | fix the bug with the nmnexc bits in cases in which they |
| | are set by a previous instruction and not cleared by |
| | the save. The frame will be unimp only if the final |
| | instruction in an emulation routine caused the exception |
| | by doing an fmove <ea>,fp0. The exception operand, in |
| | internal format, is in fptemp. |
| | |
| do_clean: |
| cmpib #UNIMP_40_SIZE-4,1(%a7) |
| bnes do_con |
| moveql #13,%d0 |in orig, need to zero 14 lwords |
| bras do_build |
| do_con: |
| cmpib #UNIMP_41_SIZE-4,1(%a7) |
| bnes do_restore |frame must be busy |
| moveql #11,%d0 |in rev, need to zero 12 lwords |
| |
| do_build: |
| moveb (%a7),VER_TMP(%a6) |
| clrl (%a7) |
| loop2: |
| clrl -(%a7) |clear and dec a7 |
| dbra %d0,loop2 |
| | |
| | Use a1 as pointer into new frame. a6 is not correct if an unimp or |
| | busy frame was created as the result of an exception on the final |
| | instruction of an emulation routine. |
| | |
| | We need to set the nmcexc bits if the exception is E1. Otherwise, |
| | the exc taken will be inex2. |
| | |
| leal BUSY_SIZE+LOCAL_SIZE(%a7),%a1 |init a1 for new frame |
| moveb VER_TMP(%a6),(%a7) |write busy fmt word |
| moveb #BUSY_SIZE-4,1(%a7) |
| movel FP_SCR1(%a6),WBTEMP_EX(%a1) |write |
| movel FP_SCR1+4(%a6),WBTEMP_HI(%a1) |exceptional op to |
| movel FP_SCR1+8(%a6),WBTEMP_LO(%a1) |wbtemp |
| | btst.b #E1,E_BYTE(%a1) |
| | beq.b do_restore |
| bfextu USER_FPSR(%a6){#17:#4},%d0 |get snan/operr/ovfl/unfl bits |
| bfins %d0,NMCEXC(%a1){#4:#4} |and insert them in nmcexc |
| movel USER_FPSR(%a6),FPSR_SHADOW(%a1) |set exc bits |
| orl #sx_mask,E_BYTE(%a1) |
| |
| do_restore: |
| moveml USER_DA(%a6),%d0-%d1/%a0-%a1 |
| fmovemx USER_FP0(%a6),%fp0-%fp3 |
| fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar |
| frestore (%a7)+ |
| tstb RES_FLG(%a6) |RES_FLG indicates a "continuation" frame |
| beq cont |
| bsr bug1384 |
| cont: |
| unlk %a6 |
| | |
| | If trace mode enabled, then go to trace handler. This handler |
| | cannot have any fp instructions. If there are fp inst's and an |
| | exception has been restored into the machine then the exception |
| | will occur upon execution of the fp inst. This is not desirable |
| | in the kernel (supervisor mode). See MC68040 manual Section 9.3.8. |
| | |
| finish_up: |
| btstb #7,(%a7) |test T1 in SR |
| bnes g_trace |
| btstb #6,(%a7) |test T0 in SR |
| bnes g_trace |
| bral fpsp_done |
| | |
| | Change integer stack to look like trace stack |
| | The address of the instruction that caused the |
| | exception is already in the integer stack (is |
| | the same as the saved friar) |
| | |
| | If the current frame is already a 6-word stack then all |
| | that needs to be done is to change the vector# to TRACE. |
| | If the frame is only a 4-word stack (meaning we got here |
| | on an Unsupported data type exception), then we need to grow |
| | the stack an extra 2 words and get the FPIAR from the FPU. |
| | |
| g_trace: |
| bftst EXC_VEC-4(%sp){#0:#4} |
| bne g_easy |
| |
| subw #4,%sp | make room |
| movel 4(%sp),(%sp) |
| movel 8(%sp),4(%sp) |
| subw #BUSY_SIZE,%sp |
| fsave (%sp) |
| fmovel %fpiar,BUSY_SIZE+EXC_EA-4(%sp) |
| frestore (%sp) |
| addw #BUSY_SIZE,%sp |
| |
| g_easy: |
| movew #TRACE_VEC,EXC_VEC-4(%a7) |
| bral real_trace |
| | |
| | This is a work-around for hardware bug 1384. |
| | |
| bug1384: |
| link %a5,#0 |
| fsave -(%sp) |
| cmpib #0x41,(%sp) | check for correct frame |
| beq frame_41 |
| bgt nofix | if more advanced mask, do nada |
| |
| frame_40: |
| tstb 1(%sp) | check to see if idle |
| bne notidle |
| idle40: |
| clrl (%sp) | get rid of old fsave frame |
| movel %d1,USER_D1(%a6) | save d1 |
| movew #8,%d1 | place unimp frame instead |
| loop40: clrl -(%sp) |
| dbra %d1,loop40 |
| movel USER_D1(%a6),%d1 | restore d1 |
| movel #0x40280000,-(%sp) |
| frestore (%sp)+ |
| unlk %a5 |
| rts |
| |
| frame_41: |
| tstb 1(%sp) | check to see if idle |
| bne notidle |
| idle41: |
| clrl (%sp) | get rid of old fsave frame |
| movel %d1,USER_D1(%a6) | save d1 |
| movew #10,%d1 | place unimp frame instead |
| loop41: clrl -(%sp) |
| dbra %d1,loop41 |
| movel USER_D1(%a6),%d1 | restore d1 |
| movel #0x41300000,-(%sp) |
| frestore (%sp)+ |
| unlk %a5 |
| rts |
| |
| notidle: |
| bclrb #etemp15_bit,-40(%a5) |
| frestore (%sp)+ |
| unlk %a5 |
| rts |
| |
| nofix: |
| frestore (%sp)+ |
| unlk %a5 |
| rts |
| |
| |end |
