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|| $Id: fpsp.defs,v 1.2 2001-09-27 12:01:22 chris Exp $|| fpsp.h 3.3 3.3|| Copyright (C) Motorola, Inc. 1990| All Rights Reserved|| THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA| The copyright notice above does not evidence any| actual or intended publication of such source code.| fpsp.h --- stack frame offsets during FPSP exception handling|| These equates are used to access the exception frame, the fsave| frame and any local variables needed by the FPSP package.|| All FPSP handlers begin by executing:|| link a6,#-LOCAL_SIZE| fsave -(a7)| movem.l d0-d1/a0-a1,USER_DA(a6)| fmovem.x fp0-fp3,USER_FP0(a6)| fmove.l fpsr/fpcr/fpiar,USER_FPSR(a6)|| After initialization, the stack looks like this:|| A7 ---> +-------------------------------+| | || | FPU fsave area || | || +-------------------------------+| | || | FPSP Local Variables || | including || | saved registers || | || +-------------------------------+| A6 ---> | Saved A6 || +-------------------------------+| | || | Exception Frame || | || | ||| Positive offsets from A6 refer to the exception frame. Negative| offsets refer to the Local Variable area and the fsave area.| The fsave frame is also accessible 'from the top' via A7.|| On exit, the handlers execute:|| movem.l USER_DA(a6),d0-d1/a0-a1| fmovem.x USER_FP0(a6),fp0-fp3| fmove.l USER_FPSR(a6),fpsr/fpcr/fpiar| frestore (a7)+| unlk a6|| and then either 'bra fpsp_done' if the exception was completely| handled by the package, or 'bra real_xxxx' which is an external| label to a routine that will process a real exception of the| type that was generated. Some handlers may omit the 'frestore'| if the FPU state after the exception is idle.|| Sometimes the exception handler will transform the fsave area| because it needs to report an exception back to the user. This| can happen if the package is entered for an unimplemented float| instruction that generates (say) an underflow. Alternatively,| a second fsave frame can be pushed onto the stack and the| handler exit code will reload the new frame and discard the old.|| The registers d0, d1, a0, a1 and fp0-fp3 are always saved and| restored from the 'local variable' area and can be used as| temporaries. If a routine needs to change any| of these registers, it should modify the saved copy and let| the handler exit code restore the value.||----------------------------------------------------------------------|| Local Variables on the stack|.set LOCAL_SIZE,192 | bytes needed for local variables.set LV,-LOCAL_SIZE | convenient base value|.set USER_DA,LV+0 | save space for D0-D1,A0-A1.set USER_D0,LV+0 | saved user D0.set USER_D1,LV+4 | saved user D1.set USER_A0,LV+8 | saved user A0.set USER_A1,LV+12 | saved user A1.set USER_FP0,LV+16 | saved user FP0.set USER_FP1,LV+28 | saved user FP1.set USER_FP2,LV+40 | saved user FP2.set USER_FP3,LV+52 | saved user FP3.set USER_FPCR,LV+64 | saved user FPCR.set FPCR_ENABLE,USER_FPCR+2 | FPCR exception enable.set FPCR_MODE,USER_FPCR+3 | FPCR rounding mode control.set USER_FPSR,LV+68 | saved user FPSR.set FPSR_CC,USER_FPSR+0 | FPSR condition code.set FPSR_QBYTE,USER_FPSR+1 | FPSR quotient.set FPSR_EXCEPT,USER_FPSR+2 | FPSR exception.set FPSR_AEXCEPT,USER_FPSR+3 | FPSR accrued exception.set USER_FPIAR,LV+72 | saved user FPIAR.set FP_SCR1,LV+76 | room for a temporary float value.set FP_SCR2,LV+92 | room for a temporary float value.set L_SCR1,LV+108 | room for a temporary long value.set L_SCR2,LV+112 | room for a temporary long value.set STORE_FLG,LV+116.set BINDEC_FLG,LV+117 | used in bindec.set DNRM_FLG,LV+118 | used in res_func.set RES_FLG,LV+119 | used in res_func.set DY_MO_FLG,LV+120 | dyadic/monadic flag.set UFLG_TMP,LV+121 | temporary for uflag errata.set CU_ONLY,LV+122 | cu-only flag.set VER_TMP,LV+123 | temp holding for version number.set L_SCR3,LV+124 | room for a temporary long value.set FP_SCR3,LV+128 | room for a temporary float value.set FP_SCR4,LV+144 | room for a temporary float value.set FP_SCR5,LV+160 | room for a temporary float value.set FP_SCR6,LV+176||NEXT equ LV+192 ;need to increase LOCAL_SIZE||--------------------------------------------------------------------------|| fsave offsets and bit definitions|| Offsets are defined from the end of an fsave because the last 10| words of a busy frame are the same as the unimplemented frame.|.set CU_SAVEPC,LV-92 | micro-pc for CU (1 byte).set FPR_DIRTY_BITS,LV-91 | fpr dirty bits|.set WBTEMP,LV-76 | write back temp (12 bytes).set WBTEMP_EX,WBTEMP | wbtemp sign and exponent (2 bytes).set WBTEMP_HI,WBTEMP+4 | wbtemp mantissa [63:32] (4 bytes).set WBTEMP_LO,WBTEMP+8 | wbtemp mantissa [31:00] (4 bytes)|.set WBTEMP_SGN,WBTEMP+2 | used to store sign|.set FPSR_SHADOW,LV-64 | fpsr shadow reg|.set FPIARCU,LV-60 | Instr. addr. reg. for CU (4 bytes)|.set CMDREG2B,LV-52 | cmd reg for machine 2.set CMDREG3B,LV-48 | cmd reg for E3 exceptions (2 bytes)|.set NMNEXC,LV-44 | NMNEXC (unsup,snan bits only).set nmn_unsup_bit,1.set nmn_snan_bit,0|.set NMCEXC,LV-43 | NMNEXC & NMCEXC.set nmn_operr_bit,7.set nmn_ovfl_bit,6.set nmn_unfl_bit,5.set nmc_unsup_bit,4.set nmc_snan_bit,3.set nmc_operr_bit,2.set nmc_ovfl_bit,1.set nmc_unfl_bit,0|.set STAG,LV-40 | source tag (1 byte).set WBTEMP_GRS,LV-40 | alias wbtemp guard, round, sticky.set guard_bit,1 | guard bit is bit number 1.set round_bit,0 | round bit is bit number 0.set stag_mask,0xE0 | upper 3 bits are source tag type.set denorm_bit,7 | bit determins if denorm or unnorm.set etemp15_bit,4 | etemp exponent bit #15.set wbtemp66_bit,2 | wbtemp mantissa bit #66.set wbtemp1_bit,1 | wbtemp mantissa bit #1.set wbtemp0_bit,0 | wbtemp mantissa bit #0|.set STICKY,LV-39 | holds sticky bit.set sticky_bit,7|.set CMDREG1B,LV-36 | cmd reg for E1 exceptions (2 bytes).set kfact_bit,12 | distinguishes static/dynamic k-factor| ;on packed move outs. NOTE: this| ;equate only works when CMDREG1B is in| ;a register.|.set CMDWORD,LV-35 | command word in cmd1b.set direction_bit,5 | bit 0 in opclass.set size_bit2,12 | bit 2 in size field|.set DTAG,LV-32 | dest tag (1 byte).set dtag_mask,0xE0 | upper 3 bits are dest type tag.set fptemp15_bit,4 | fptemp exponent bit #15|.set WB_BYTE,LV-31 | holds WBTE15 bit (1 byte).set wbtemp15_bit,4 | wbtemp exponent bit #15|.set E_BYTE,LV-28 | holds E1 and E3 bits (1 byte).set E1,2 | which bit is E1 flag.set E3,1 | which bit is E3 flag.set SFLAG,0 | which bit is S flag|.set T_BYTE,LV-27 | holds T and U bits (1 byte).set XFLAG,7 | which bit is X flag.set UFLAG,5 | which bit is U flag.set TFLAG,4 | which bit is T flag|.set FPTEMP,LV-24 | fptemp (12 bytes).set FPTEMP_EX,FPTEMP | fptemp sign and exponent (2 bytes).set FPTEMP_HI,FPTEMP+4 | fptemp mantissa [63:32] (4 bytes).set FPTEMP_LO,FPTEMP+8 | fptemp mantissa [31:00] (4 bytes)|.set FPTEMP_SGN,FPTEMP+2 | used to store sign|.set ETEMP,LV-12 | etemp (12 bytes).set ETEMP_EX,ETEMP | etemp sign and exponent (2 bytes).set ETEMP_HI,ETEMP+4 | etemp mantissa [63:32] (4 bytes).set ETEMP_LO,ETEMP+8 | etemp mantissa [31:00] (4 bytes)|.set ETEMP_SGN,ETEMP+2 | used to store sign|.set EXC_SR,4 | exception frame status register.set EXC_PC,6 | exception frame program counter.set EXC_VEC,10 | exception frame vector (format+vector#).set EXC_EA,12 | exception frame effective address||--------------------------------------------------------------------------|| FPSR/FPCR bits|.set neg_bit,3 | negative result.set z_bit,2 | zero result.set inf_bit,1 | infinity result.set nan_bit,0 | not-a-number result|.set q_sn_bit,7 | sign bit of quotient byte|.set bsun_bit,7 | branch on unordered.set snan_bit,6 | signalling nan.set operr_bit,5 | operand error.set ovfl_bit,4 | overflow.set unfl_bit,3 | underflow.set dz_bit,2 | divide by zero.set inex2_bit,1 | inexact result 2.set inex1_bit,0 | inexact result 1|.set aiop_bit,7 | accrued illegal operation.set aovfl_bit,6 | accrued overflow.set aunfl_bit,5 | accrued underflow.set adz_bit,4 | accrued divide by zero.set ainex_bit,3 | accrued inexact|| FPSR individual bit masks|.set neg_mask,0x08000000.set z_mask,0x04000000.set inf_mask,0x02000000.set nan_mask,0x01000000|.set bsun_mask,0x00008000.set snan_mask,0x00004000.set operr_mask,0x00002000.set ovfl_mask,0x00001000.set unfl_mask,0x00000800.set dz_mask,0x00000400.set inex2_mask,0x00000200.set inex1_mask,0x00000100|.set aiop_mask,0x00000080 | accrued illegal operation.set aovfl_mask,0x00000040 | accrued overflow.set aunfl_mask,0x00000020 | accrued underflow.set adz_mask,0x00000010 | accrued divide by zero.set ainex_mask,0x00000008 | accrued inexact|| FPSR combinations used in the FPSP|.set dzinf_mask,inf_mask+dz_mask+adz_mask.set opnan_mask,nan_mask+operr_mask+aiop_mask.set nzi_mask,0x01ffffff | clears N, Z, and I.set unfinx_mask,unfl_mask+inex2_mask+aunfl_mask+ainex_mask.set unf2inx_mask,unfl_mask+inex2_mask+ainex_mask.set ovfinx_mask,ovfl_mask+inex2_mask+aovfl_mask+ainex_mask.set inx1a_mask,inex1_mask+ainex_mask.set inx2a_mask,inex2_mask+ainex_mask.set snaniop_mask,nan_mask+snan_mask+aiop_mask.set naniop_mask,nan_mask+aiop_mask.set neginf_mask,neg_mask+inf_mask.set infaiop_mask,inf_mask+aiop_mask.set negz_mask,neg_mask+z_mask.set opaop_mask,operr_mask+aiop_mask.set unfl_inx_mask,unfl_mask+aunfl_mask+ainex_mask.set ovfl_inx_mask,ovfl_mask+aovfl_mask+ainex_mask||--------------------------------------------------------------------------|| FPCR rounding modes|.set x_mode,0x00 | round to extended.set s_mode,0x40 | round to single.set d_mode,0x80 | round to double|.set rn_mode,0x00 | round nearest.set rz_mode,0x10 | round to zero.set rm_mode,0x20 | round to minus infinity.set rp_mode,0x30 | round to plus infinity||--------------------------------------------------------------------------|| Miscellaneous equates|.set signan_bit,6 | signalling nan bit in mantissa.set sign_bit,7|.set rnd_stky_bit,29 | round/sticky bit of mantissa| this can only be used if in a data register.set sx_mask,0x01800000 | set s and x bits in word $48|.set LOCAL_EX,0.set LOCAL_SGN,2.set LOCAL_HI,4.set LOCAL_LO,8.set LOCAL_GRS,12 | valid ONLY for FP_SCR1, FP_SCR2||.set norm_tag,0x00 | tag bits in {7:5} position.set zero_tag,0x20.set inf_tag,0x40.set nan_tag,0x60.set dnrm_tag,0x80|| fsave sizes and formats|.set VER_4,0x40 | fpsp compatible version numbers| are in the $40s {$40-$4f}.set VER_40,0x40 | original version number.set VER_41,0x41 | revision version number|.set BUSY_SIZE,100 | size of busy frame.set BUSY_FRAME,LV-BUSY_SIZE | start of busy frame|.set UNIMP_40_SIZE,44 | size of orig unimp frame.set UNIMP_41_SIZE,52 | size of rev unimp frame|.set IDLE_SIZE,4 | size of idle frame.set IDLE_FRAME,LV-IDLE_SIZE | start of idle frame|| exception vectors|.set TRACE_VEC,0x2024 | trace trap.set FLINE_VEC,0x002C | 'real' F-line.set UNIMP_VEC,0x202C | unimplemented.set INEX_VEC,0x00C4|.set dbl_thresh,0x3C01.set sgl_thresh,0x3F81|
