#include "fpsp-namespace.h" // // // 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write byte, word, or long data to Dn // // // Copyright (C) Motorola, Inc. 1990 // All Rights Reserved // // THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA // The copyright notice above does not evidence any // actual or intended publication of such source code. //UTIL idnt 2,1 | Motorola 040 Floating Point Software Package |section 8 #include "fpsp.defs" |xref mem_read .global g_dfmtou .global g_opcls .global g_rndpr .global get_fline .global 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: .long 0x7fff0000,0x00000000,0x00000000,0x00000000 // ;largest +ext EXT_PLRG: .long 0x7ffe0000,0xffffffff,0xffffffff,0x00000000 // ;largest magnitude +sgl in ext SGL_PLRG: .long 0x407e0000,0xffffff00,0x00000000,0x00000000 // ;largest magnitude +dbl in ext DBL_PLRG: .long 0x43fe0000,0xffffffff,0xfffff800,0x00000000 // ;largest -ext tblovfl: .long EXT_RN .long EXT_RZ .long EXT_RM .long EXT_RP .long SGL_RN .long SGL_RZ .long SGL_RM .long SGL_RP .long DBL_RN .long DBL_RZ .long DBL_RM .long DBL_RP .long error .long error .long error .long 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) // .global ovf_r_k ovf_r_k: lea ETEMP(%a6),%a0 //a0 points to source operand bclrb #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. .global ovf_r_x2 ovf_r_x2: btstb #E3,E_BYTE(%a6) //check for nu exception beql ovf_e1_exc //it is cu exception ovf_e3_exc: movew CMDREG3B(%a6),%d0 //get the command word andiw #0x00000060,%d0 //clear all bits except 6 and 5 cmpil #0x00000040,%d0 beql ovff_sgl //force precision is single cmpil #0x00000060,%d0 beql ovff_dbl //force precision is double movew CMDREG3B(%a6),%d0 //get the command word again andil #0x7f,%d0 //clear all except operation cmpil #0x33,%d0 beql ovf_fsgl //fsglmul or fsgldiv cmpil #0x30,%d0 beql ovf_fsgl bra ovf_fpcr //instruction is none of the above // ;use FPCR ovf_e1_exc: movew CMDREG1B(%a6),%d0 //get command word andil #0x00000044,%d0 //clear all bits except 6 and 2 cmpil #0x00000040,%d0 beql ovff_sgl //the instruction is force single cmpil #0x00000044,%d0 beql ovff_dbl //the instruction is force double movew CMDREG1B(%a6),%d0 //again get the command word andil #0x0000007f,%d0 //clear all except the op code cmpil #0x00000027,%d0 beql ovf_fsgl //fsglmul cmpil #0x00000024,%d0 beql ovf_fsgl //fsgldiv bra ovf_fpcr //none of the above, use FPCR // // // Inst is either fsgldiv or fsglmul. Force extended precision. // ovf_fsgl: clrl %d0 bra ovf_res ovff_sgl: movel #0x00000001,%d0 //set single bra ovf_res ovff_dbl: movel #0x00000002,%d0 //set double bra ovf_res // // The precision is in the fpcr. // ovf_fpcr: bfextu FPCR_MODE(%a6){#0:#2},%d0 //set round precision bra 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. // .global 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 // .global ovf_res ovf_res: lsll #2,%d0 //move round precision to d0{3:2} bfextu FPCR_MODE(%a6){#2:#2},%d1 //set round mode orl %d1,%d0 //index is fmt:mode in d0{3:0} leal tblovfl,%a1 //load a1 with table address movel %a1@(%d0:l:4),%a1 //use d0 as index to the table jmp (%a1) //go to the correct routine // //case DEST_FMT = EXT // EXT_RN: leal EXT_PINF,%a1 //answer is +/- infinity bsetb #inf_bit,FPSR_CC(%a6) bra set_sign //now go set the sign EXT_RZ: leal EXT_PLRG,%a1 //answer is +/- large number bra set_sign //now go set the sign EXT_RM: tstb LOCAL_SGN(%a0) //if negative overflow beqs e_rm_pos e_rm_neg: leal EXT_PINF,%a1 //answer is negative infinity orl #neginf_mask,USER_FPSR(%a6) bra end_ovfr e_rm_pos: leal EXT_PLRG,%a1 //answer is large positive number bra end_ovfr EXT_RP: tstb LOCAL_SGN(%a0) //if negative overflow beqs e_rp_pos e_rp_neg: leal EXT_PLRG,%a1 //answer is large negative number bsetb #neg_bit,FPSR_CC(%a6) bra end_ovfr e_rp_pos: leal EXT_PINF,%a1 //answer is positive infinity bsetb #inf_bit,FPSR_CC(%a6) bra end_ovfr // //case DEST_FMT = DBL // DBL_RN: leal EXT_PINF,%a1 //answer is +/- infinity bsetb #inf_bit,FPSR_CC(%a6) bra set_sign DBL_RZ: leal DBL_PLRG,%a1 //answer is +/- large number bra set_sign //now go set the sign DBL_RM: tstb LOCAL_SGN(%a0) //if negative overflow beqs d_rm_pos d_rm_neg: leal EXT_PINF,%a1 //answer is negative infinity orl #neginf_mask,USER_FPSR(%a6) bra end_ovfr //inf is same for all precisions (ext,dbl,sgl) d_rm_pos: leal DBL_PLRG,%a1 //answer is large positive number bra end_ovfr DBL_RP: tstb LOCAL_SGN(%a0) //if negative overflow beqs d_rp_pos d_rp_neg: leal DBL_PLRG,%a1 //answer is large negative number bsetb #neg_bit,FPSR_CC(%a6) bra end_ovfr d_rp_pos: leal EXT_PINF,%a1 //answer is positive infinity bsetb #inf_bit,FPSR_CC(%a6) bra end_ovfr // //case DEST_FMT = SGL // SGL_RN: leal EXT_PINF,%a1 //answer is +/- infinity bsetb #inf_bit,FPSR_CC(%a6) bras set_sign SGL_RZ: leal SGL_PLRG,%a1 //answer is +/- large number bras set_sign SGL_RM: tstb LOCAL_SGN(%a0) //if negative overflow beqs s_rm_pos s_rm_neg: leal EXT_PINF,%a1 //answer is negative infinity orl #neginf_mask,USER_FPSR(%a6) bras end_ovfr s_rm_pos: leal SGL_PLRG,%a1 //answer is large positive number bras end_ovfr SGL_RP: tstb LOCAL_SGN(%a0) //if negative overflow beqs s_rp_pos s_rp_neg: leal SGL_PLRG,%a1 //answer is large negative number bsetb #neg_bit,FPSR_CC(%a6) bras end_ovfr s_rp_pos: leal EXT_PINF,%a1 //answer is positive infinity bsetb #inf_bit,FPSR_CC(%a6) bras end_ovfr set_sign: tstb LOCAL_SGN(%a0) //if negative overflow beqs end_ovfr neg_sign: bsetb #neg_bit,FPSR_CC(%a6) end_ovfr: movew LOCAL_EX(%a1),LOCAL_EX(%a0) //do not overwrite sign movel LOCAL_HI(%a1),LOCAL_HI(%a0) movel 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: movel USER_FPIAR(%a6),%a0 //opcode address movel #0,-(%a7) //reserve a word on the stack leal 2(%a7),%a1 //point to low word of temporary movel #2,%d0 //count bsrl mem_read movel (%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 g_opcls //get opclass in d0{2:0} cmpw #0x0003,%d0 //check for opclass 011 bnes op_0x0 // // For move out instructions (opclass 011) the destination format // is the same as the rounding precision. Pass results from g_dfmtou. // bsr g_dfmtou rts op_0x0: btstb #E3,E_BYTE(%a6) beql unf_e1_exc //branch to e1 underflow unf_e3_exc: movel CMDREG3B(%a6),%d0 //rounding precision in d0{10:9} bfextu %d0{#9:#2},%d0 //move the rounding prec bits to d0{1:0} cmpil #0x2,%d0 beql unff_sgl //force precision is single cmpil #0x3,%d0 //force precision is double beql unff_dbl movew CMDREG3B(%a6),%d0 //get the command word again andil #0x7f,%d0 //clear all except operation cmpil #0x33,%d0 beql unf_fsgl //fsglmul or fsgldiv cmpil #0x30,%d0 beql unf_fsgl //fsgldiv or fsglmul bra unf_fpcr unf_e1_exc: movel CMDREG1B(%a6),%d0 //get 32 bits off the stack, 1st 16 bits // ;are the command word andil #0x00440000,%d0 //clear all bits except bits 6 and 2 cmpil #0x00400000,%d0 beql unff_sgl //force single cmpil #0x00440000,%d0 //force double beql unff_dbl movel CMDREG1B(%a6),%d0 //get the command word again andil #0x007f0000,%d0 //clear all bits except the operation cmpil #0x00270000,%d0 beql unf_fsgl //fsglmul cmpil #0x00240000,%d0 beql 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: movel #1,%d0 //return 1 rts // // Force double // unff_dbl: movel #2,%d0 //return 2 rts // // Force extended // unf_fsgl: movel #0,%d0 rts // // Get rounding precision set in FPCR{7:6}. // unf_fpcr: movel 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: btstb #E3,E_BYTE(%a6) beqs opc_1b //if set, go to cmdreg1b opc_3b: clrl %d0 //if E3, only opclass 0x0 is possible rts opc_1b: movel 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: btstb #E3,E_BYTE(%a6) beqs op011 clrl %d0 //if E1, size is always ext rts op011: movel CMDREG1B(%a6),%d0 bfextu %d0{#3:#3},%d0 //dest fmt from cmdreg1b{12:10} cmpb #1,%d0 //check for single bnes not_sgl movel #1,%d0 rts not_sgl: cmpb #5,%d0 //check for double bnes not_dbl movel #2,%d0 rts not_dbl: clrl %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: .long 0x00000000,0x00000000,0x00000000,0x00000000 // ;+zero SGL_PZRO: .long 0x3f810000,0x00000000,0x00000000,0x00000000 // ;+zero DBL_PZRO: .long 0x3c010000,0x00000000,0x00000000,0x00000000 // ;smallest +ext denorm EXT_PSML: .long 0x00000000,0x00000000,0x00000001,0x00000000 // ;smallest +sgl denorm SGL_PSML: .long 0x3f810000,0x00000100,0x00000000,0x00000000 // ;smallest +dbl denorm DBL_PSML: .long 0x3c010000,0x00000000,0x00000800,0x00000000 // // 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: .long uEXT_RN .long uEXT_RZ .long uEXT_RM .long uEXT_RP .long uSGL_RN .long uSGL_RZ .long uSGL_RM .long uSGL_RP .long uDBL_RN .long uDBL_RZ .long uDBL_RM .long uDBL_RP .long uDBL_RN .long uDBL_RZ .long uDBL_RM .long uDBL_RP .global unf_sub unf_sub: lsll #2,%d0 //move round precision to d0{3:2} bfextu FPCR_MODE(%a6){#2:#2},%d1 //set round mode orl %d1,%d0 //index is fmt:mode in d0{3:0} leal tblunf,%a1 //load a1 with table address movel %a1@(%d0:l:4),%a1 //use d0 as index to the table jmp (%a1) //go to the correct routine // //case DEST_FMT = EXT // uEXT_RN: leal EXT_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bra uset_sign //now go set the sign uEXT_RZ: leal EXT_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bra uset_sign //now go set the sign uEXT_RM: tstb LOCAL_SGN(%a0) //if negative underflow beqs ue_rm_pos ue_rm_neg: leal EXT_PSML,%a1 //answer is negative smallest denorm bsetb #neg_bit,FPSR_CC(%a6) bra end_unfr ue_rm_pos: leal EXT_PZRO,%a1 //answer is positive zero bsetb #z_bit,FPSR_CC(%a6) bra end_unfr uEXT_RP: tstb LOCAL_SGN(%a0) //if negative underflow beqs ue_rp_pos ue_rp_neg: leal EXT_PZRO,%a1 //answer is negative zero oril #negz_mask,USER_FPSR(%a6) bra end_unfr ue_rp_pos: leal EXT_PSML,%a1 //answer is positive smallest denorm bra end_unfr // //case DEST_FMT = DBL // uDBL_RN: leal DBL_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bra uset_sign uDBL_RZ: leal DBL_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bra uset_sign //now go set the sign uDBL_RM: tstb LOCAL_SGN(%a0) //if negative overflow beqs ud_rm_pos ud_rm_neg: leal DBL_PSML,%a1 //answer is smallest denormalized negative bsetb #neg_bit,FPSR_CC(%a6) bra end_unfr ud_rm_pos: leal DBL_PZRO,%a1 //answer is positive zero bsetb #z_bit,FPSR_CC(%a6) bra end_unfr uDBL_RP: tstb LOCAL_SGN(%a0) //if negative overflow beqs ud_rp_pos ud_rp_neg: leal DBL_PZRO,%a1 //answer is negative zero oril #negz_mask,USER_FPSR(%a6) bra end_unfr ud_rp_pos: leal DBL_PSML,%a1 //answer is smallest denormalized negative bra end_unfr // //case DEST_FMT = SGL // uSGL_RN: leal SGL_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bras uset_sign uSGL_RZ: leal SGL_PZRO,%a1 //answer is +/- zero bsetb #z_bit,FPSR_CC(%a6) bras uset_sign uSGL_RM: tstb LOCAL_SGN(%a0) //if negative overflow beqs us_rm_pos us_rm_neg: leal SGL_PSML,%a1 //answer is smallest denormalized negative bsetb #neg_bit,FPSR_CC(%a6) bras end_unfr us_rm_pos: leal SGL_PZRO,%a1 //answer is positive zero bsetb #z_bit,FPSR_CC(%a6) bras end_unfr uSGL_RP: tstb LOCAL_SGN(%a0) //if negative overflow beqs us_rp_pos us_rp_neg: leal SGL_PZRO,%a1 //answer is negative zero oril #negz_mask,USER_FPSR(%a6) bras end_unfr us_rp_pos: leal SGL_PSML,%a1 //answer is smallest denormalized positive bras end_unfr uset_sign: tstb LOCAL_SGN(%a0) //if negative overflow beqs end_unfr uneg_sign: bsetb #neg_bit,FPSR_CC(%a6) end_unfr: movew LOCAL_EX(%a1),LOCAL_EX(%a0) //be careful not to overwrite sign movel LOCAL_HI(%a1),LOCAL_HI(%a0) movel 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: .long byte_d0 .long byte_d1 .long byte_d2 .long byte_d3 .long byte_d4 .long byte_d5 .long byte_d6 .long byte_d7 .long word_d0 .long word_d1 .long word_d2 .long word_d3 .long word_d4 .long word_d5 .long word_d6 .long word_d7 .long long_d0 .long long_d1 .long long_d2 .long long_d3 .long long_d4 .long long_d5 .long long_d6 .long long_d7 reg_dest: leal pregdst,%a0 movel %a0@(%d1:l:4),%a0 jmp (%a0) byte_d0: moveb L_SCR1(%a6),USER_D0+3(%a6) rts byte_d1: moveb L_SCR1(%a6),USER_D1+3(%a6) rts byte_d2: moveb L_SCR1(%a6),%d2 rts byte_d3: moveb L_SCR1(%a6),%d3 rts byte_d4: moveb L_SCR1(%a6),%d4 rts byte_d5: moveb L_SCR1(%a6),%d5 rts byte_d6: moveb L_SCR1(%a6),%d6 rts byte_d7: moveb L_SCR1(%a6),%d7 rts word_d0: movew L_SCR1(%a6),USER_D0+2(%a6) rts word_d1: movew L_SCR1(%a6),USER_D1+2(%a6) rts word_d2: movew L_SCR1(%a6),%d2 rts word_d3: movew L_SCR1(%a6),%d3 rts word_d4: movew L_SCR1(%a6),%d4 rts word_d5: movew L_SCR1(%a6),%d5 rts word_d6: movew L_SCR1(%a6),%d6 rts word_d7: movew L_SCR1(%a6),%d7 rts long_d0: movel L_SCR1(%a6),USER_D0(%a6) rts long_d1: movel L_SCR1(%a6),USER_D1(%a6) rts long_d2: movel L_SCR1(%a6),%d2 rts long_d3: movel L_SCR1(%a6),%d3 rts long_d4: movel L_SCR1(%a6),%d4 rts long_d5: movel L_SCR1(%a6),%d5 rts long_d6: movel L_SCR1(%a6),%d6 rts long_d7: movel L_SCR1(%a6),%d7 rts |end