1 /* @(#)doprnt.c 4.1 (Berkeley) 12/21/80 */ 2 # C library -- conversions 3 4 .globl __doprnt 5 .globl __flsbuf 6 7 #define vbit 1 8 #define flags r10 9 #define ndfnd 0 10 #define prec 1 11 #define zfill 2 12 #define minsgn 3 13 #define plssgn 4 14 #define numsgn 5 15 #define caps 6 16 #define blank 7 17 #define gflag 8 18 #define dpflag 9 19 #define width r9 20 #define ndigit r8 21 #define llafx r7 22 #define lrafx r6 23 #define fdesc -4(fp) 24 #define exp -8(fp) 25 #define sexp -12(fp) 26 #define nchar -16(fp) 27 #define sign -17(fp) 28 .set ch.zer,'0 # cpp doesn't like single appostrophes 29 30 .align 2 31 strtab: # translate table for detecting null and percent 32 .byte 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 33 .byte 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 34 .byte ' ,'!,'",'#,'$, 0,'&,'','(,'),'*,'+,',,'-,'.,'/ 35 .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,':,';,'<,'=,'>,'? 36 .byte '@,'A,'B,'C,'D,'E,'F,'G,'H,'I,'J,'K,'L,'M,'N,'O 37 .byte 'P,'Q,'R,'S,'T,'U,'V,'W,'X,'Y,'Z,'[,'\,'],'^,'_ 38 .byte '`,'a,'b,'c,'d,'e,'f,'g,'h,'i,'j,'k,'l,'m,'n,'o 39 .byte 'p,'q,'r,'s,'t,'u,'v,'w,'x,'y,'z,'{,'|,'},'~,127 40 .byte 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143 41 .byte 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159 42 .byte 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175 43 .byte 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191 44 .byte 192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207 45 .byte 208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223 46 .byte 224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239 47 .byte 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255 48 49 strfoo: 50 clrl r4 # fix interrupt race 51 jbr strok # and try again 52 strmore: 53 movzbl (r1)+,r2 # one char 54 tstb (r3)[r2] # translate 55 jeql stresc2 # bad guy in disguise (outbuf is full) 56 strout2: # enter here to force out r2; r0,r1 must be set 57 pushr $3 # save input descriptor 58 pushl fdesc # FILE 59 pushl r2 # the char 60 calls $2,__flsbuf # please empty the buffer and handle 1 char 61 tstl r0 # successful? 62 jgeq strm1 # yes 63 jbcs $31,nchar,strm1 # turn on sign bit of nchar to signify error 64 strm1: 65 incl nchar # count the char 66 popr $3 # get input descriptor back 67 strout: # enter via bsb with (r0,r1)=input descriptor 68 movab strtab,r3 # table address 69 movq *fdesc,r4 # output descriptor 70 jbs $31,r4,strfoo # negative count is a no no 71 strok: 72 addl2 r0,nchar # we intend to move this many chars 73 movtuc r0,(r1),$0,(r3),r4,(r5) 74 movpsl r2 # squirrel away condition codes 75 movq r4,*fdesc # update output descriptor 76 subl2 r0,nchar # some chars not moved 77 jbs $vbit,r2,stresc # terminated by escape? 78 sobgeq r0,strmore # no; but out buffer might be full 79 stresc: 80 rsb 81 stresc2: 82 incl r0 # fix the length 83 decl r1 # and the addr 84 movl $1<vbit,r2 # fake condition codes 85 rsb 86 87 errdone: 88 jbcs $31,nchar,prdone # set error bit 89 prdone: 90 movl nchar,r0 91 ret 92 93 .align 1 94 __doprnt: 95 .word 0xfc0 # uses r11-r6 96 movab -256(sp),sp # work space 97 movl 4(ap),r11 # addr of format string 98 movl 12(ap),fdesc # output FILE ptr 99 movl 8(ap),ap # addr of first arg 100 clrl nchar # number of chars transferred 101 loop: 102 movzwl $65535,r0 # pseudo length 103 movl r11,r1 # fmt addr 104 bsbw strout # copy to output, stop at null or percent 105 movl r1,r11 # new fmt 106 jbc $vbit,r2,loop # if no escape, then very long fmt 107 tstb (r11)+ # escape; null or percent? 108 jeql prdone # null means end of fmt 109 110 movl sp,r5 # reset output buffer pointer 111 clrq r9 # width; flags 112 clrq r6 # lrafx,llafx 113 longorunsg: # we can ignore both of these distinctions 114 short: 115 L4a: 116 movzbl (r11)+,r0 # so capital letters can tail merge 117 L4: caseb r0,$' ,$'x-' # format char 118 L5: 119 .word space-L5 # space 120 .word fmtbad-L5 # ! 121 .word fmtbad-L5 # " 122 .word sharp-L5 # # 123 .word fmtbad-L5 # $ 124 .word fmtbad-L5 # % 125 .word fmtbad-L5 # & 126 .word fmtbad-L5 # ' 127 .word fmtbad-L5 # ( 128 .word fmtbad-L5 # ) 129 .word indir-L5 # * 130 .word plus-L5 # + 131 .word fmtbad-L5 # , 132 .word minus-L5 # - 133 .word dot-L5 # . 134 .word fmtbad-L5 # / 135 .word gnum0-L5 # 0 136 .word gnum-L5 # 1 137 .word gnum-L5 # 2 138 .word gnum-L5 # 3 139 .word gnum-L5 # 4 140 .word gnum-L5 # 5 141 .word gnum-L5 # 6 142 .word gnum-L5 # 7 143 .word gnum-L5 # 8 144 .word gnum-L5 # 9 145 .word fmtbad-L5 # : 146 .word fmtbad-L5 # ; 147 .word fmtbad-L5 # < 148 .word fmtbad-L5 # = 149 .word fmtbad-L5 # > 150 .word fmtbad-L5 # ? 151 .word fmtbad-L5 # @ 152 .word fmtbad-L5 # A 153 .word fmtbad-L5 # B 154 .word fmtbad-L5 # C 155 .word decimal-L5 # D 156 .word capital-L5 # E 157 .word fmtbad-L5 # F 158 .word capital-L5 # G 159 .word fmtbad-L5 # H 160 .word fmtbad-L5 # I 161 .word fmtbad-L5 # J 162 .word fmtbad-L5 # K 163 .word fmtbad-L5 # L 164 .word fmtbad-L5 # M 165 .word fmtbad-L5 # N 166 .word octal-L5 # O 167 .word fmtbad-L5 # P 168 .word fmtbad-L5 # Q 169 .word fmtbad-L5 # R 170 .word fmtbad-L5 # S 171 .word fmtbad-L5 # T 172 .word unsigned-L5 # U 173 .word fmtbad-L5 # V 174 .word fmtbad-L5 # W 175 .word hex-L5 # X 176 .word fmtbad-L5 # Y 177 .word fmtbad-L5 # Z 178 .word fmtbad-L5 # [ 179 .word fmtbad-L5 # \ 180 .word fmtbad-L5 # ] 181 .word fmtbad-L5 # ^ 182 .word fmtbad-L5 # _ 183 .word fmtbad-L5 # ` 184 .word fmtbad-L5 # a 185 .word fmtbad-L5 # b 186 .word charac-L5 # c 187 .word decimal-L5 # d 188 .word scien-L5 # e 189 .word float-L5 # f 190 .word general-L5 # g 191 .word short-L5 # h 192 .word fmtbad-L5 # i 193 .word fmtbad-L5 # j 194 .word fmtbad-L5 # k 195 .word longorunsg-L5 # l 196 .word fmtbad-L5 # m 197 .word fmtbad-L5 # n 198 .word octal-L5 # o 199 .word fmtbad-L5 # p 200 .word fmtbad-L5 # q 201 .word fmtbad-L5 # r 202 .word string-L5 # s 203 .word fmtbad-L5 # t 204 .word unsigned-L5 # u 205 .word fmtbad-L5 # v 206 .word fmtbad-L5 # w 207 .word hex-L5 # x 208 fmtbad: 209 movb r0,(r5)+ # print the unfound character 210 jeql errdone # dumb users who end the format with a % 211 jbr prbuf 212 capital: 213 bisl2 $1<caps,flags # note that it was capitalized 214 xorb2 $'a^'A,r0 # make it small 215 jbr L4 # and try again 216 217 string: 218 movl ndigit,r0 219 jbs $prec,flags,L20 # max length was specified 220 mnegl $1,r0 # default max length 221 L20: movl (ap)+,r2 # addr first byte 222 locc $0,r0,(r2) # find the zero at the end 223 movl r1,r5 # addr last byte +1 224 movl r2,r1 # addr first byte 225 jbr prstr 226 227 htab: .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,'a,'b,'c,'d,'e,'f 228 Htab: .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,'A,'B,'C,'D,'E,'F 229 230 octal: 231 movl $30,r2 # init position 232 movl $3,r3 # field width 233 movab htab,llafx # translate table 234 jbr L10 235 236 hex: 237 movl $28,r2 # init position 238 movl $4,r3 # field width 239 movab htab,llafx # translate table 240 jbc $caps,flags,L10 241 movab Htab,llafx 242 L10: mnegl r3,r6 # increment 243 clrl r1 244 addl2 $4,r5 # room for left affix (2) and slop [forced sign?] 245 movl (ap)+,r0 # fetch arg 246 L11: extzv r2,r3,r0,r1 # pull out a digit 247 movb (llafx)[r1],(r5)+ # convert to character 248 L12: acbl $0,r6,r2,L11 # continue until done 249 clrq r6 # lrafx, llafx 250 clrb (r5) # flag end 251 skpc $'0,$11,4(sp) # skip over leading zeroes 252 jbc $numsgn,flags,prn3 # easy if no left affix 253 tstl -4(ap) # original value 254 jeql prn3 # no affix on 0, for some reason 255 cmpl r3,$4 # were we doing hex or octal? 256 jneq L12a # octal 257 movb $'x,r0 258 jbc $caps,flags,L12b 259 movb $'X,r0 260 L12b: movb r0,-(r1) 261 movl $2,llafx # leading 0x for hex is an affix 262 L12a: movb $'0,-(r1) # leading zero for octal is a digit, not an affix 263 jbr prn3 # omit sign (plus, blank) massaging 264 265 unsigned: 266 lunsigned: 267 bicl2 $1<plssgn|1<blank,flags # omit sign (plus, blank) massaging 268 extzv $1,$31,(ap),r0 # right shift logical 1 bit 269 cvtlp r0,$10,(sp) # convert [n/2] to packed 270 movp $10,(sp),8(sp) # copy packed 271 addp4 $10,8(sp),$10,(sp) # 2*[n/2] in packed, at (sp) 272 blbc (ap)+,L14 # n was even 273 addp4 $1,pone,$10,(sp) # n was odd 274 jbr L14 275 276 patdec: # editpc pattern for decimal printing 277 .byte 0xAA # eo$float 10 278 .byte 0x01 # eo$end_float 279 .byte 0 # eo$end 280 281 decimal: 282 cvtlp (ap)+,$10,(sp) # 10 digits max 283 jgeq L14 284 incl llafx # minus sign is a left affix 285 L14: editpc $10,(sp),patdec,8(sp) # ascii at 8(sp); r5=end+1 286 skpc $' ,$11,8(sp) # skip leading blanks; r1=first 287 288 prnum: # r1=addr first byte, r5=addr last byte +1, llafx=size of signs 289 # -1(r1) vacant, for forced sign 290 tstl llafx 291 jneq prn3 # already some left affix, dont fuss 292 jbc $plssgn,flags,prn2 293 movb $'+,-(r1) # needs a plus sign 294 jbr prn4 295 prn2: jbc $blank,flags,prn3 296 movb $' ,-(r1) # needs a blank sign 297 prn4: incl llafx 298 prn3: jbs $prec,flags,prn1 299 movl $1,ndigit # default precision is 1 300 prn1: subl3 r1,r5,lrafx # raw width 301 subl2 llafx,lrafx # number of digits 302 subl2 lrafx,ndigit # number of leading zeroes needed 303 jleq prstr # none 304 addl2 llafx,r1 # where current digits start 305 pushl r1 # movcx gobbles registers 306 # check bounds on users who say %.300d 307 movab 32(r5)[ndigit],r2 308 subl2 fp,r2 309 jlss prn5 310 subl2 r2,ndigit 311 prn5: 312 # 313 movc3 lrafx,(r1),(r1)[ndigit] # make room in middle 314 movc5 $0,(r1),$ch.zer,ndigit,*(sp) # '0 fill 315 subl3 llafx,(sp)+,r1 # first byte addr 316 addl3 lrafx,r3,r5 # last byte addr +1 317 318 prstr: # r1=addr first byte; r5=addr last byte +1 319 # width=minimum width; llafx=len. left affix 320 # ndigit=<avail> 321 subl3 r1,r5,ndigit # raw width 322 subl3 ndigit,width,r0 # pad length 323 jleq padlno # in particular, no left padding 324 jbs $minsgn,flags,padlno 325 # extension for %0 flag causing left zero padding to field width 326 jbs $zfill,flags,padlz 327 # this bsbb needed even if %0 flag extension is removed 328 bsbb padb # blank pad on left 329 jbr padnlz 330 padlz: 331 movl llafx,r0 332 jleq padnlx # left zero pad requires left affix first 333 subl2 r0,ndigit # part of total length will be transferred 334 subl2 r0,width # and will account for part of minimum width 335 bsbw strout # left affix 336 padnlx: 337 subl3 ndigit,width,r0 # pad length 338 bsbb padz # zero pad on left 339 padnlz: 340 # end of extension for left zero padding 341 padlno: # remaining: root, possible right padding 342 subl2 ndigit,width # root reduces minimum width 343 movl ndigit,r0 # root length 344 p1: bsbw strout # transfer to output buffer 345 p3: jbc $vbit,r2,padnpct # percent sign (or null byte via %c) ? 346 decl r0 # yes; adjust count 347 movzbl (r1)+,r2 # fetch byte 348 movq *fdesc,r4 # output buffer descriptor 349 sobgeq r4,p2 # room at the out [inn] ? 350 bsbw strout2 # no; force it, then try rest 351 jbr p3 # here we go 'round the mullberry bush, ... 352 p2: movb r2,(r5)+ # hand-deposit the percent or null 353 incl nchar # count it 354 movq r4,*fdesc # store output descriptor 355 jbr p1 # what an expensive hiccup! 356 padnpct: 357 movl width,r0 # size of pad 358 jleq loop 359 bsbb padb 360 jbr loop 361 362 padz: 363 movb $'0,r2 364 jbr pad 365 padb: 366 movb $' ,r2 367 pad: 368 subl2 r0,width # pad width decreases minimum width 369 pushl r1 # save non-pad addr 370 movl r0,llafx # remember width of pad 371 subl2 r0,sp # allocate 372 movc5 $0,(r0),r2,llafx,(sp) # create pad string 373 movl llafx,r0 # length 374 movl sp,r1 # addr 375 bsbw strout 376 addl2 llafx,sp # deallocate 377 movl (sp)+,r1 # recover non-pad addr 378 rsb 379 380 pone: .byte 0x1C # packed 1 381 382 charac: 383 movl (ap)+,r0 # word containing the char 384 movb r0,(r5)+ # one byte, that's all 385 386 prbuf: 387 movl sp,r1 # addr first byte 388 jbr prstr 389 390 space: bisl2 $1<blank,flags # constant width e fmt, no plus sign 391 jbr L4a 392 sharp: bisl2 $1<numsgn,flags # 'self identifying', please 393 jbr L4a 394 plus: bisl2 $1<plssgn,flags # always print sign for floats 395 jbr L4a 396 minus: bisl2 $1<minsgn,flags # left justification, please 397 jbr L4a 398 gnum0: jbs $ndfnd,flags,gnum 399 jbs $prec,flags,gnump # ignore when reading precision 400 bisl2 $1<zfill,flags # leading zero fill, please 401 gnum: jbs $prec,flags,gnump 402 moval (width)[width],width # width *= 5; 403 movaw -ch.zer(r0)[width],width # width = 2*witdh + r0 - '0'; 404 jbr gnumd 405 gnump: moval (ndigit)[ndigit],ndigit # ndigit *= 5; 406 movaw -ch.zer(r0)[ndigit],ndigit # ndigit = 2*ndigit + r0 - '0'; 407 gnumd: bisl2 $1<ndfnd,flags # digit seen 408 jbr L4a 409 dot: clrl ndigit # start on the precision 410 bisl2 $1<prec,flags 411 bicl2 $1<ndfnd,flags 412 jbr L4a 413 indir: 414 jbs $prec,flags,in1 415 movl (ap)+,width # width specified by parameter 416 jgeq gnumd 417 xorl2 $1<minsgn,flags # parameterized left adjustment 418 mnegl width,width 419 jbr gnumd 420 in1: 421 movl (ap)+,ndigit # precision specified by paratmeter 422 jgeq gnumd 423 mnegl ndigit,ndigit 424 jbr gnumd 425 426 float: 427 jbs $prec,flags,float1 428 movl $6,ndigit # default # digits to right of decpt. 429 float1: bsbw fltcvt 430 addl3 exp,ndigit,r7 431 movl r7,r6 # for later "underflow" checking 432 bgeq fxplrd 433 clrl r7 # poor programmer planning 434 fxplrd: cmpl r7,$31 # expressible in packed decimal? 435 bleq fnarro # yes 436 movl $31,r7 437 fnarro: subl3 $17,r7,r0 # where to round 438 ashp r0,$17,(sp),$5,r7,16(sp) # do it 439 bvc fnovfl 440 # band-aid for microcode error (spurious overflow) 441 # clrl r0 # assume even length result 442 # jlbc r7,fleven # right 443 # movl $4,r0 # odd length result 444 #fleven: cmpv r0,$4,16(sp),$0 # top digit zero iff true overflow 445 # bneq fnovfl 446 # end band-aid 447 aobleq $0,r6,fnovfl # if "underflow" then jump 448 movl r7,r0 449 incl exp 450 incl r7 451 ashp r0,$1,pone,$0,r7,16(sp) 452 ashl $-1,r7,r0 # displ to last byte 453 bisb2 sign,16(sp)[r0] # insert sign 454 fnovfl: 455 movab 16(sp),r1 # packed source 456 movl r7,r6 # packed length 457 pushab prnum # goto prnum after fall-through call to fedit 458 459 460 # enter via bsb 461 # r1=addr of packed source 462 # 16(r1) used to unpack source 463 # 48(r1) used to construct pattern to unpack source 464 # 48(r1) used to hold result 465 # r6=length of packed source (destroyed) 466 # exp=# digits to left of decimal point (destroyed) 467 # ndigit=# digits to right of decimal point (destroyed) 468 # sign=1 if negative, 0 otherwise 469 # stack will be used for work space for pattern and unpacked source 470 # exits with 471 # r1=addr of punctuated result 472 # r5=addr of last byte +1 473 # llafx=1 if minus sign inserted, 0 otherwise 474 fedit: 475 pushab 48(r1) # save result addr 476 movab 48(r1),r3 # pattern addr 477 movb $0x03,(r3)+ # eo$set_signif 478 movc5 $0,(r1),$0x91,r6,(r3) # eo$move 1 479 clrb (r3) # eo$end 480 editpc r6,(r1),48(r1),16(r1) # unpack 'em all 481 subl3 r6,r5,r1 # addr unpacked source 482 movl (sp),r3 # punctuated output placed here 483 clrl llafx 484 jlbc sign,f1 485 movb $'-,(r3)+ # negative 486 incl llafx 487 f1: movl exp,r0 488 jgtr f2 489 movb $'0,(r3)+ # must have digit before decimal point 490 jbr f3 491 f2: cmpl r0,r6 # limit on packed length 492 jleq f4 493 movl r6,r0 494 f4: subl2 r0,r6 # eat some digits 495 subl2 r0,exp # from the exponent 496 movc3 r0,(r1),(r3) # (most of the) digits to left of decimal point 497 movl exp,r0 # need any more? 498 jleq f3 499 movc5 $0,(r1),$'0,r0,(r3) # '0 fill 500 f3: movl ndigit,r0 # # digits to right of decimal point 501 jgtr f5 502 jbs $numsgn,flags,f5 # no decimal point unless forced 503 jbcs $dpflag,flags,f6 # no decimal point 504 f5: movb $'.,(r3)+ # the decimal point 505 f6: mnegl exp,r0 # "leading" zeroes to right of decimal point 506 jleq f9 507 cmpl r0,ndigit # cant exceed this many 508 jleq fa 509 movl ndigit,r0 510 fa: subl2 r0,ndigit 511 movc5 $0,(r1),$'0,r0,(r3) 512 f9: movl ndigit,r0 513 cmpl r0,r6 # limit on packed length 514 jleq f7 515 movl r6,r0 516 f7: subl2 r0,ndigit # eat some digits from the fraction 517 movc3 r0,(r1),(r3) # (most of the) digits to right of decimal point 518 movl ndigit,r0 # need any more? 519 jleq f8 520 # check bounds on users who say %.300f 521 movab 32(r3)[r0],r2 522 subl2 fp,r2 523 jlss fb 524 subl2 r2,r0 # truncate, willy-nilly 525 movl r0,ndigit # and no more digits later, either 526 fb: 527 # 528 subl2 r0,ndigit # eat some digits from the fraction 529 movc5 $0,(r1),$'0,r0,(r3) # '0 fill 530 f8: movl r3,r5 # addr last byte +1 531 popr $1<1 # [movl (sp)+,r1] addr first byte 532 rsb 533 534 patexp: .byte 0x03 # eo$set_signif 535 .byte 0x44,'e # eo$insert 'e 536 .byte 0x42,'+ # eo$load_plus '+ 537 .byte 0x04 # eo$store_sign 538 .byte 0x92 # eo$move 2 539 .byte 0 # eo$end 540 541 scien: 542 incl ndigit 543 jbs $prec,flags,L23 544 movl $7,ndigit 545 L23: bsbw fltcvt # get packed digits 546 movl ndigit,r7 547 cmpl r7,$31 # expressible in packed decimal? 548 jleq snarro # yes 549 movl $31,r7 550 snarro: subl3 $17,r7,r0 # rounding position 551 ashp r0,$17,(sp),$5,r7,16(sp) # shift and round 552 bvc snovfl 553 # band-aid for microcode error (spurious overflow) 554 # clrl r0 # assume even length result 555 # jlbc ndigit,sceven # right 556 # movl $4,r0 # odd length result 557 #sceven: cmpv r0,$4,16(sp),$0 # top digit zero iff true overflow 558 # bneq snovfl 559 # end band-aid 560 incl exp # rounding overflowed to 100... 561 subl3 $1,r7,r0 562 ashp r0,$1,pone,$0,r7,16(sp) 563 ashl $-1,r7,r0 # displ to last byte 564 bisb2 sign,16(sp)[r0] # insert sign 565 snovfl: 566 jbs $gflag,flags,gfmt # %g format 567 movab 16(sp),r1 568 bsbb eedit 569 eexp: 570 movl r1,r6 # save fwa from destruction by cvtlp 571 subl3 $1,sexp,r0 # 1P exponent 572 cvtlp r0,$2,(sp) # packed 573 editpc $2,(sp),patexp,(r5) 574 movl r6,r1 # fwa 575 jbc $caps,flags,prnum 576 xorb2 $'e^'E,-4(r5) 577 jbr prnum 578 579 eedit: 580 movl r7,r6 # packed length 581 decl ndigit # 1 digit before decimal point 582 movl exp,sexp # save from destruction 583 movl $1,exp # and pretend 584 jbr fedit 585 586 gfmt: 587 addl3 $3,exp,r0 # exp is 1 more than e 588 jlss gfmte # (e+1)+3<0, e+4<=-1, e<=-5 589 subl2 $3,r0 # exp [==(e+1)] 590 cmpl r0,ndigit 591 jgtr gfmte # e+1>n, e>=n 592 gfmtf: 593 movl r7,r6 594 subl2 r0,ndigit # n-e-1 595 movab 16(sp),r1 596 bsbw fedit 597 g1: jbs $numsgn,flags,g2 598 jbs $dpflag,flags,g2 # dont strip if no decimal point 599 g3: cmpb -(r5),$'0 # strip trailing zeroes 600 jeql g3 601 cmpb (r5),$'. # and trailing decimal point 602 jeql g2 603 incl r5 604 g2: jbc $gflag,flags,eexp 605 jbr prnum 606 gfmte: 607 movab 16(sp),r1 # packed source 608 bsbw eedit 609 jbsc $gflag,flags,g1 # gflag now means "use %f" [hence no exponent] 610 611 general: 612 jbs $prec,flags,gn1 613 movl $6,ndigit # default precision is 6 significant digits 614 gn1: tstl ndigit # cannot allow precision of 0 615 jgtr gn2 616 movl $1,ndigit # change 0 to 1, willy-nilly 617 gn2: jbcs $gflag,flags,L23 618 jbr L23 # safety net 619 620 # convert double-floating at (ap) to 17-digit packed at (sp), 621 # set 'sign' and 'exp', advance ap. 622 fltcvt: 623 clrb sign 624 movd (ap)+,r5 625 jeql fzero 626 bgtr fpos 627 mnegd r5,r5 628 incb sign 629 fpos: 630 extzv $7,$8,r5,r2 # exponent of 2 631 movab -0200(r2),r2 # unbias 632 mull2 $59,r2 # 59/196: 3rd convergent continued frac of log10(2) 633 jlss eneg 634 movab 196(r2),r2 635 eneg: 636 movab -98(r2),r2 637 divl2 $196,r2 638 bsbw expten 639 cmpd r0,r5 640 bgtr ceil 641 incl r2 642 ceil: movl r2,exp 643 mnegl r2,r2 644 cmpl r2,$29 # 10^(29+9) is all we can handle 645 bleq getman 646 muld2 ten16,r5 647 subl2 $16,r2 648 getman: addl2 $9,r2 # -ceil(log10(x)) + 9 649 bsbb expten 650 emodd r0,r4,r5,r0,r5 # (r0+r4)*r5; r0=int, r5=frac 651 fz1: cvtlp r0,$9,16(sp) # leading 9 digits 652 ashp $8,$9,16(sp),$0,$17,4(sp) # as top 9 of 17 653 emodd ten8,$0,r5,r0,r5 654 cvtlp r0,$8,16(sp) # trailing 8 digits 655 # if precision >= 17, must round here 656 movl ndigit,r7 # so figure out what precision is 657 pushab scien 658 cmpl (sp)+,(sp) 659 jleq gm1 # who called us? 660 addl2 exp,r7 # float; adjust for exponent 661 gm1: cmpl r7,$17 662 jlss gm2 663 cmpd r5,$0d0.5 # must round here; check fraction 664 jlss gm2 665 bisb2 $0x10,8+4(sp) # increment l.s. digit 666 gm2: # end of "round here" code 667 addp4 $8,16(sp),$17,4(sp) # combine leading and trailing 668 bisb2 sign,12(sp) # and insert sign 669 rsb 670 fzero: clrl r0 671 movl $1,exp # 0.000e+00 and 0.000 rather than 0.000e-01 and .000 672 jbr fz1 673 674 .align 2 675 lsb: .long 0x00010000 # lsb in the crazy floating-point format 676 677 # return 10^r2 as a double float in r0||r1 and 8 extra bits of precision in r4 678 # preserve r2, r5||r6 679 expten: 680 movd $0d1.0,r0 # begin computing 10^exp10 681 clrl r4 # bit counter 682 movad ten1,r3 # table address 683 tstl r2 684 bgeq e10lp 685 mnegl r2,r2 # get absolute value 686 jbss $6,r2,e10lp # flag as negative 687 e10lp: jbc r4,r2,el1 # want this power? 688 muld2 (r3),r0 # yes 689 el1: addl2 $8,r3 # advance to next power 690 aobleq $5,r4,e10lp # through 10^32 691 jbcc $6,r2,el2 # correct for negative exponent 692 divd3 r0,$0d1.0,r0 # by taking reciprocal 693 cmpl $28,r2 694 jneq enm28 695 addl2 lsb,r1 # 10**-28 needs lsb incremented 696 enm28: mnegl r2,r2 # original exponent of 10 697 el2: addl3 $5*8,r2,r3 # negative bit positions are illegal? 698 jbc r3,xlsbh-5,eoklsb 699 subl2 lsb,r1 # lsb was too high 700 eoklsb: 701 movzbl xprec[r2],r4 # 8 extra bits 702 rsb 703 704 # powers of ten 705 .align 2 706 ten1: .word 0x4220,0,0,0 707 ten2: .word 0x43c8,0,0,0 708 ten4: .word 0x471c,0x4000,0,0 709 ten8: .word 0x4dbe,0xbc20,0,0 710 ten16: .word 0x5b0e,0x1bc9,0xbf04,0 711 ten32: .word 0x759d,0xc5ad,0xa82b,0x70b6 712 713 # whether lsb is too high or not 714 .byte 1:0,1:0,1:0,1:0,1:1,1:0,1:1,1:0 # -40 thru -33 715 .byte 1:0,1:1,1:0,1:0,1:0,1:0,1:1,1:0 # -32 thru -25 716 .byte 1:0,1:0,1:1,1:1,1:1,1:1,1:0,1:0 # -24 thru -17 717 .byte 1:0,1:1,1:0,1:0,1:1,1:1,1:1,1:1 # -16 thru -9 718 .byte 1:1,1:1,1:1,1:0,1:0,1:0,1:0,1:1 # -8 thru -1 719 xlsbh: 720 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 0 thru 7 721 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 8 thru 15 722 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 16 thru 23 723 .byte 1:0,1:1,1:1,1:0,1:1,1:1,1:1,1:1 # 24 thru 31 724 .byte 1:1,1:1,1:1,1:1,1:1,1:1,1:1 # 32 thru 38 725 726 # bytes of extra precision 727 .byte 0x56,0x76,0xd3,0x88,0xb5,0x62 # -38 thru -33 728 .byte 0xba,0xf5,0x32,0x3e,0x0e,0x48,0xdb,0x51 # -32 thru -25 729 .byte 0x53,0x27,0xb1,0xef,0xeb,0xa5,0x07,0x49 # -24 thru -17 730 .byte 0x5b,0xd9,0x0f,0x13,0xcd,0xff,0xbf,0x97 # -16 thru -9 731 .byte 0xfd,0xbc,0xb6,0x23,0x2c,0x3b,0x0a,0xcd # -8 thru -1 732 xprec: 733 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 0 thru 7 734 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 8 thru 15 735 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 16 thru 23 736 .byte 0x00,0xa0,0xc8,0x3a,0x84,0xe4,0xdc,0x92 # 24 thru 31 737 .byte 0x9b,0x00,0xc0,0x58,0xae,0x18,0xef # 32 thru 38 738