* MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP * M68000 Hi-Performance Microprocessor Division * M68040 Software Package * * M68040 Software Package Copyright (c) 1993, 1994 Motorola Inc. * All rights reserved. * * THE SOFTWARE is provided on an "AS IS" basis and without warranty. * To the maximum extent permitted by applicable law, * MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED, * INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A * PARTICULAR PURPOSE and any warranty against infringement with * regard to the SOFTWARE (INCLUDING ANY MODIFIED VERSIONS THEREOF) * and any accompanying written materials. * * To the maximum extent permitted by applicable law, * IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER * (INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS * PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR * OTHER PECUNIARY LOSS) ARISING OF THE USE OR INABILITY TO USE THE * SOFTWARE. Motorola assumes no responsibility for the maintenance * and support of the SOFTWARE. * * You are hereby granted a copyright license to use, modify, and * distribute the SOFTWARE so long as this entire notice is retained * without alteration in any modified and/or redistributed versions, * and that such modified versions are clearly identified as such. * No licenses are granted by implication, estoppel or otherwise * under any patents or trademarks of Motorola, Inc. * * util.sa 3.7 7/29/91 * * This file contains routines used by other programs. * * ovf_res: used by overflow to force the correct * result. ovf_r_k, ovf_r_x2, ovf_r_x3 are * derivatives of this routine. * get_fline: get user's opcode word * g_dfmtou: returns the destination format. * g_opcls: returns the opclass of the float instruction. * g_rndpr: returns the rounding precision. * reg_dest: write byte, word, or long data to Dn * UTIL IDNT 2,1 Motorola 040 Floating Point Software Package section 8 include fpsp.h xref mem_read xdef g_dfmtou xdef g_opcls xdef g_rndpr xdef get_fline xdef reg_dest * * Final result table for ovf_res. Note that the negative counterparts * are unnecessary as ovf_res always returns the sign separately from * the exponent. * ;+inf EXT_PINF dc.l $7fff0000,$00000000,$00000000,$00000000 * ;largest +ext EXT_PLRG dc.l $7ffe0000,$ffffffff,$ffffffff,$00000000 * ;largest magnitude +sgl in ext SGL_PLRG dc.l $407e0000,$ffffff00,$00000000,$00000000 * ;largest magnitude +dbl in ext DBL_PLRG dc.l $43fe0000,$ffffffff,$fffff800,$00000000 * ;largest -ext tblovfl: dc.l EXT_RN dc.l EXT_RZ dc.l EXT_RM dc.l EXT_RP dc.l SGL_RN dc.l SGL_RZ dc.l SGL_RM dc.l SGL_RP dc.l DBL_RN dc.l DBL_RZ dc.l DBL_RM dc.l DBL_RP dc.l error dc.l error dc.l error dc.l error * * ovf_r_k --- overflow result calculation * * This entry point is used by kernel_ex. * * This forces the destination precision to be extended * * Input: operand in ETEMP * Output: a result is in ETEMP (internal extended format) * xdef ovf_r_k ovf_r_k: lea ETEMP(a6),a0 ;a0 points to source operand bclr.b #sign_bit,ETEMP_EX(a6) sne ETEMP_SGN(a6) ;convert to internal IEEE format * * ovf_r_x2 --- overflow result calculation * * This entry point used by x_ovfl. (opclass 0 and 2) * * Input a0 points to an operand in the internal extended format * Output a0 points to the result in the internal extended format * * This sets the round precision according to the user's FPCR unless the * instruction is fsgldiv or fsglmul or fsadd, fdadd, fsub, fdsub, fsmul, * fdmul, fsdiv, fddiv, fssqrt, fsmove, fdmove, fsabs, fdabs, fsneg, fdneg. * If the instruction is fsgldiv of fsglmul, the rounding precision must be * extended. If the instruction is not fsgldiv or fsglmul but a force- * precision instruction, the rounding precision is then set to the force * precision. xdef ovf_r_x2 ovf_r_x2: btst.b #E3,E_BYTE(a6) ;check for nu exception beq.l ovf_e1_exc ;it is cu exception ovf_e3_exc: move.w CMDREG3B(a6),d0 ;get the command word andi.w #$00000060,d0 ;clear all bits except 6 and 5 cmpi.l #$00000040,d0 beq.l ovff_sgl ;force precision is single cmpi.l #$00000060,d0 beq.l ovff_dbl ;force precision is double move.w CMDREG3B(a6),d0 ;get the command word again andi.l #$7f,d0 ;clear all except operation cmpi.l #$33,d0 beq.l ovf_fsgl ;fsglmul or fsgldiv cmpi.l #$30,d0 beq.l ovf_fsgl bra ovf_fpcr ;instruction is none of the above * ;use FPCR ovf_e1_exc: move.w CMDREG1B(a6),d0 ;get command word andi.l #$00000044,d0 ;clear all bits except 6 and 2 cmpi.l #$00000040,d0 beq.l ovff_sgl ;the instruction is force single cmpi.l #$00000044,d0 beq.l ovff_dbl ;the instruction is force double move.w CMDREG1B(a6),d0 ;again get the command word andi.l #$0000007f,d0 ;clear all except the op code cmpi.l #$00000027,d0 beq.l ovf_fsgl ;fsglmul cmpi.l #$00000024,d0 beq.l ovf_fsgl ;fsgldiv bra ovf_fpcr ;none of the above, use FPCR * * * Inst is either fsgldiv or fsglmul. Force extended precision. * ovf_fsgl: clr.l d0 bra.b ovf_res ovff_sgl: move.l #$00000001,d0 ;set single bra.b ovf_res ovff_dbl: move.l #$00000002,d0 ;set double bra.b ovf_res * * The precision is in the fpcr. * ovf_fpcr: bfextu FPCR_MODE(a6){0:2},d0 ;set round precision bra.b ovf_res * * * ovf_r_x3 --- overflow result calculation * * This entry point used by x_ovfl. (opclass 3 only) * * Input a0 points to an operand in the internal extended format * Output a0 points to the result in the internal extended format * * This sets the round precision according to the destination size. * xdef ovf_r_x3 ovf_r_x3: bsr g_dfmtou ;get dest fmt in d0{1:0} * ;for fmovout, the destination format * ;is the rounding precision * * ovf_res --- overflow result calculation * * Input: * a0 points to operand in internal extended format * Output: * a0 points to result in internal extended format * xdef ovf_res ovf_res: lsl.l #2,d0 ;move round precision to d0{3:2} bfextu FPCR_MODE(a6){2:2},d1 ;set round mode or.l d1,d0 ;index is fmt:mode in d0{3:0} lea.l tblovfl,a1 ;load a1 with table address move.l (a1,d0*4),a1 ;use d0 as index to the table jmp (a1) ;go to the correct routine * *case DEST_FMT = EXT * EXT_RN: lea.l EXT_PINF,a1 ;answer is +/- infinity bset.b #inf_bit,FPSR_CC(a6) bra set_sign ;now go set the sign EXT_RZ: lea.l EXT_PLRG,a1 ;answer is +/- large number bra set_sign ;now go set the sign EXT_RM: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b e_rm_pos e_rm_neg: lea.l EXT_PINF,a1 ;answer is negative infinity or.l #neginf_mask,USER_FPSR(a6) bra end_ovfr e_rm_pos: lea.l EXT_PLRG,a1 ;answer is large positive number bra end_ovfr EXT_RP: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b e_rp_pos e_rp_neg: lea.l EXT_PLRG,a1 ;answer is large negative number bset.b #neg_bit,FPSR_CC(a6) bra end_ovfr e_rp_pos: lea.l EXT_PINF,a1 ;answer is positive infinity bset.b #inf_bit,FPSR_CC(a6) bra end_ovfr * *case DEST_FMT = DBL * DBL_RN: lea.l EXT_PINF,a1 ;answer is +/- infinity bset.b #inf_bit,FPSR_CC(a6) bra set_sign DBL_RZ: lea.l DBL_PLRG,a1 ;answer is +/- large number bra set_sign ;now go set the sign DBL_RM: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b d_rm_pos d_rm_neg: lea.l EXT_PINF,a1 ;answer is negative infinity or.l #neginf_mask,USER_FPSR(a6) bra end_ovfr ;inf is same for all precisions (ext,dbl,sgl) d_rm_pos: lea.l DBL_PLRG,a1 ;answer is large positive number bra end_ovfr DBL_RP: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b d_rp_pos d_rp_neg: lea.l DBL_PLRG,a1 ;answer is large negative number bset.b #neg_bit,FPSR_CC(a6) bra end_ovfr d_rp_pos: lea.l EXT_PINF,a1 ;answer is positive infinity bset.b #inf_bit,FPSR_CC(a6) bra end_ovfr * *case DEST_FMT = SGL * SGL_RN: lea.l EXT_PINF,a1 ;answer is +/- infinity bset.b #inf_bit,FPSR_CC(a6) bra.b set_sign SGL_RZ: lea.l SGL_PLRG,a1 ;anwer is +/- large number bra.b set_sign SGL_RM: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b s_rm_pos s_rm_neg: lea.l EXT_PINF,a1 ;answer is negative infinity or.l #neginf_mask,USER_FPSR(a6) bra.b end_ovfr s_rm_pos: lea.l SGL_PLRG,a1 ;answer is large positive number bra.b end_ovfr SGL_RP: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b s_rp_pos s_rp_neg: lea.l SGL_PLRG,a1 ;answer is large negative number bset.b #neg_bit,FPSR_CC(a6) bra.b end_ovfr s_rp_pos: lea.l EXT_PINF,a1 ;answer is postive infinity bset.b #inf_bit,FPSR_CC(a6) bra.b end_ovfr set_sign: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b end_ovfr neg_sign: bset.b #neg_bit,FPSR_CC(a6) end_ovfr: move.w LOCAL_EX(a1),LOCAL_EX(a0) ;do not overwrite sign move.l LOCAL_HI(a1),LOCAL_HI(a0) move.l LOCAL_LO(a1),LOCAL_LO(a0) rts * * ERROR * error: rts * * get_fline --- get f-line opcode of interrupted instruction * * Returns opcode in the low word of d0. * get_fline: move.l USER_FPIAR(a6),a0 ;opcode address clr.l -(a7) ;reserve a word on the stack lea.l 2(a7),a1 ;point to low word of temporary move.l #2,d0 ;count bsr.l mem_read move.l (a7)+,d0 rts * * g_rndpr --- put rounding precision in d0{1:0} * * valid return codes are: * 00 - extended * 01 - single * 10 - double * * begin * get rounding precision (cmdreg3b{6:5}) * begin * case opclass = 011 (move out) * get destination format - this is the also the rounding precision * * case opclass = 0x0 * if E3 * *case RndPr(from cmdreg3b{6:5} = 11 then RND_PREC = DBL * *case RndPr(from cmdreg3b{6:5} = 10 then RND_PREC = SGL * case RndPr(from cmdreg3b{6:5} = 00 | 01 * use precision from FPCR{7:6} * case 00 then RND_PREC = EXT * case 01 then RND_PREC = SGL * case 10 then RND_PREC = DBL * else E1 * use precision in FPCR{7:6} * case 00 then RND_PREC = EXT * case 01 then RND_PREC = SGL * case 10 then RND_PREC = DBL * end * g_rndpr: bsr.w g_opcls ;get opclass in d0{2:0} cmp.w #$0003,d0 ;check for opclass 011 bne.b op_0x0 * * For move out instructions (opclass 011) the destination format * is the same as the rounding precision. Pass results from g_dfmtou. * bsr.w g_dfmtou rts op_0x0: btst.b #E3,E_BYTE(a6) beq.l unf_e1_exc ;branch to e1 underflow unf_e3_exc: move.l CMDREG3B(a6),d0 ;rounding precision in d0{10:9} bfextu d0{9:2},d0 ;move the rounding prec bits to d0{1:0} cmpi.l #$2,d0 beq.l unff_sgl ;force precision is single cmpi.l #$3,d0 ;force precision is double beq.l unff_dbl move.w CMDREG3B(a6),d0 ;get the command word again andi.l #$7f,d0 ;clear all except operation cmpi.l #$33,d0 beq.l unf_fsgl ;fsglmul or fsgldiv cmpi.l #$30,d0 beq.l unf_fsgl ;fsgldiv or fsglmul bra unf_fpcr unf_e1_exc: move.l CMDREG1B(a6),d0 ;get 32 bits off the stack, 1st 16 bits * ;are the command word andi.l #$00440000,d0 ;clear all bits except bits 6 and 2 cmpi.l #$00400000,d0 beq.l unff_sgl ;force single cmpi.l #$00440000,d0 ;force double beq.l unff_dbl move.l CMDREG1B(a6),d0 ;get the command word again andi.l #$007f0000,d0 ;clear all bits except the operation cmpi.l #$00270000,d0 beq.l unf_fsgl ;fsglmul cmpi.l #$00240000,d0 beq.l unf_fsgl ;fsgldiv bra unf_fpcr * * Convert to return format. The values from cmdreg3b and the return * values are: * cmdreg3b return precision * -------- ------ --------- * 00,01 0 ext * 10 1 sgl * 11 2 dbl * Force single * unff_sgl: move.l #1,d0 ;return 1 rts * * Force double * unff_dbl: move.l #2,d0 ;return 2 rts * * Force extended * unf_fsgl: clr.l d0 rts * * Get rounding precision set in FPCR{7:6}. * unf_fpcr: move.l USER_FPCR(a6),d0 ;rounding precision bits in d0{7:6} bfextu d0{24:2},d0 ;move the rounding prec bits to d0{1:0} rts * * g_opcls --- put opclass in d0{2:0} * g_opcls: btst.b #E3,E_BYTE(a6) beq.b opc_1b ;if set, go to cmdreg1b opc_3b: clr.l d0 ;if E3, only opclass 0x0 is possible rts opc_1b: move.l CMDREG1B(a6),d0 bfextu d0{0:3},d0 ;shift opclass bits d0{31:29} to d0{2:0} rts * * g_dfmtou --- put destination format in d0{1:0} * * If E1, the format is from cmdreg1b{12:10} * If E3, the format is extended. * * Dest. Fmt. * extended 010 -> 00 * single 001 -> 01 * double 101 -> 10 * g_dfmtou: btst.b #E3,E_BYTE(a6) beq.b op011 clr.l d0 ;if E1, size is always ext rts op011: move.l CMDREG1B(a6),d0 bfextu d0{3:3},d0 ;dest fmt from cmdreg1b{12:10} cmp.b #1,d0 ;check for single bne.b not_sgl move.l #1,d0 rts not_sgl: cmp.b #5,d0 ;check for double bne.b not_dbl move.l #2,d0 rts not_dbl: clr.l d0 ;must be extended rts * * * Final result table for unf_sub. Note that the negative counterparts * are unnecessary as unf_sub always returns the sign separately from * the exponent. * ;+zero EXT_PZRO dc.l $00000000,$00000000,$00000000,$00000000 * ;+zero SGL_PZRO dc.l $3f810000,$00000000,$00000000,$00000000 * ;+zero DBL_PZRO dc.l $3c010000,$00000000,$00000000,$00000000 * ;smallest +ext denorm EXT_PSML dc.l $00000000,$00000000,$00000001,$00000000 * ;smallest +sgl denorm SGL_PSML dc.l $3f810000,$00000100,$00000000,$00000000 * ;smallest +dbl denorm DBL_PSML dc.l $3c010000,$00000000,$00000800,$00000000 * * UNF_SUB --- underflow result calculation * * Input: * d0 contains round precision * a0 points to input operand in the internal extended format * * Output: * a0 points to correct internal extended precision result. * tblunf: dc.l uEXT_RN dc.l uEXT_RZ dc.l uEXT_RM dc.l uEXT_RP dc.l uSGL_RN dc.l uSGL_RZ dc.l uSGL_RM dc.l uSGL_RP dc.l uDBL_RN dc.l uDBL_RZ dc.l uDBL_RM dc.l uDBL_RP dc.l uDBL_RN dc.l uDBL_RZ dc.l uDBL_RM dc.l uDBL_RP xdef unf_sub unf_sub: lsl.l #2,d0 ;move round precision to d0{3:2} bfextu FPCR_MODE(a6){2:2},d1 ;set round mode or.l d1,d0 ;index is fmt:mode in d0{3:0} lea.l tblunf,a1 ;load a1 with table address move.l (a1,d0*4),a1 ;use d0 as index to the table jmp (a1) ;go to the correct routine * *case DEST_FMT = EXT * uEXT_RN: lea.l EXT_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra uset_sign ;now go set the sign uEXT_RZ: lea.l EXT_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra uset_sign ;now go set the sign uEXT_RM: tst.b LOCAL_SGN(a0) ;if negative underflow beq.b ue_rm_pos ue_rm_neg: lea.l EXT_PSML,a1 ;answer is negative smallest denorm bset.b #neg_bit,FPSR_CC(a6) bra end_unfr ue_rm_pos: lea.l EXT_PZRO,a1 ;answer is positive zero bset.b #z_bit,FPSR_CC(a6) bra end_unfr uEXT_RP: tst.b LOCAL_SGN(a0) ;if negative underflow beq.b ue_rp_pos ue_rp_neg: lea.l EXT_PZRO,a1 ;answer is negative zero ori.l #negz_mask,USER_FPSR(a6) bra end_unfr ue_rp_pos: lea.l EXT_PSML,a1 ;answer is positive smallest denorm bra end_unfr * *case DEST_FMT = DBL * uDBL_RN: lea.l DBL_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra uset_sign uDBL_RZ: lea.l DBL_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra uset_sign ;now go set the sign uDBL_RM: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b ud_rm_pos ud_rm_neg: lea.l DBL_PSML,a1 ;answer is smallest denormalized negative bset.b #neg_bit,FPSR_CC(a6) bra end_unfr ud_rm_pos: lea.l DBL_PZRO,a1 ;answer is positive zero bset.b #z_bit,FPSR_CC(a6) bra end_unfr uDBL_RP: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b ud_rp_pos ud_rp_neg: lea.l DBL_PZRO,a1 ;answer is negative zero ori.l #negz_mask,USER_FPSR(a6) bra end_unfr ud_rp_pos: lea.l DBL_PSML,a1 ;answer is smallest denormalized negative bra end_unfr * *case DEST_FMT = SGL * uSGL_RN: lea.l SGL_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra.b uset_sign uSGL_RZ: lea.l SGL_PZRO,a1 ;answer is +/- zero bset.b #z_bit,FPSR_CC(a6) bra.b uset_sign uSGL_RM: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b us_rm_pos us_rm_neg: lea.l SGL_PSML,a1 ;answer is smallest denormalized negative bset.b #neg_bit,FPSR_CC(a6) bra.b end_unfr us_rm_pos: lea.l SGL_PZRO,a1 ;answer is positive zero bset.b #z_bit,FPSR_CC(a6) bra.b end_unfr uSGL_RP: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b us_rp_pos us_rp_neg: lea.l SGL_PZRO,a1 ;answer is negative zero ori.l #negz_mask,USER_FPSR(a6) bra.b end_unfr us_rp_pos: lea.l SGL_PSML,a1 ;answer is smallest denormalized positive bra.b end_unfr uset_sign: tst.b LOCAL_SGN(a0) ;if negative overflow beq.b end_unfr uneg_sign: bset.b #neg_bit,FPSR_CC(a6) end_unfr: move.w LOCAL_EX(a1),LOCAL_EX(a0) ;be careful not to overwrite sign move.l LOCAL_HI(a1),LOCAL_HI(a0) move.l LOCAL_LO(a1),LOCAL_LO(a0) rts * * reg_dest --- write byte, word, or long data to Dn * * * Input: * L_SCR1: Data * d1: data size and dest register number formatted as: * * 32 5 4 3 2 1 0 * ----------------------------------------------- * | 0 | Size | Dest Reg # | * ----------------------------------------------- * * Size is: * 0 - Byte * 1 - Word * 2 - Long/Single * pregdst: dc.l byte_d0 dc.l byte_d1 dc.l byte_d2 dc.l byte_d3 dc.l byte_d4 dc.l byte_d5 dc.l byte_d6 dc.l byte_d7 dc.l word_d0 dc.l word_d1 dc.l word_d2 dc.l word_d3 dc.l word_d4 dc.l word_d5 dc.l word_d6 dc.l word_d7 dc.l long_d0 dc.l long_d1 dc.l long_d2 dc.l long_d3 dc.l long_d4 dc.l long_d5 dc.l long_d6 dc.l long_d7 reg_dest: lea.l pregdst,a0 move.l (a0,d1*4),a0 jmp (a0) byte_d0: move.b L_SCR1(a6),USER_D0+3(a6) rts byte_d1: move.b L_SCR1(a6),USER_D1+3(a6) rts byte_d2: move.b L_SCR1(a6),d2 rts byte_d3: move.b L_SCR1(a6),d3 rts byte_d4: move.b L_SCR1(a6),d4 rts byte_d5: move.b L_SCR1(a6),d5 rts byte_d6: move.b L_SCR1(a6),d6 rts byte_d7: move.b L_SCR1(a6),d7 rts word_d0: move.w L_SCR1(a6),USER_D0+2(a6) rts word_d1: move.w L_SCR1(a6),USER_D1+2(a6) rts word_d2: move.w L_SCR1(a6),d2 rts word_d3: move.w L_SCR1(a6),d3 rts word_d4: move.w L_SCR1(a6),d4 rts word_d5: move.w L_SCR1(a6),d5 rts word_d6: move.w L_SCR1(a6),d6 rts word_d7: move.w L_SCR1(a6),d7 rts long_d0: move.l L_SCR1(a6),USER_D0(a6) rts long_d1: move.l L_SCR1(a6),USER_D1(a6) rts long_d2: move.l L_SCR1(a6),d2 rts long_d3: move.l L_SCR1(a6),d3 rts long_d4: move.l L_SCR1(a6),d4 rts long_d5: move.l L_SCR1(a6),d5 rts long_d6: move.l L_SCR1(a6),d6 rts long_d7: move.l L_SCR1(a6),d7 rts end