1 #ifdef LIBC_SCCS 2 .data 3 _sccsid: 4 .asciz "@(#)doprnt.c 5.4 (Berkeley) 03/09/86" 5 .text 6 #endif LIBC_SCCS 7 8 # C library -- conversions 9 10 #include "DEFS.h" 11 12 .globl __doprnt 13 .globl __flsbuf 14 15 #define vbit 1 16 #define flags r10 17 #define ndfnd 0 18 #define prec 1 19 #define zfill 2 20 #define minsgn 3 21 #define plssgn 4 22 #define numsgn 5 23 #define caps 6 24 #define blank 7 25 #define gflag 8 26 #define dpflag 9 27 #define width r9 28 #define ndigit r8 29 #define llafx r7 30 #define lrafx r6 31 #define fdesc -4(fp) 32 #define exp -8(fp) 33 #define sexp -12(fp) 34 #define nchar -16(fp) 35 #define sign -17(fp) 36 .set ch.zer,'0 # cpp doesn't like single appostrophes 37 38 .align 2 39 strtab: # translate table for detecting null and percent 40 .byte 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 41 .byte 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 42 .byte ' ,'!,'",'#,'$, 0,'&,'','(,'),'*,'+,',,'-,'.,'/ 43 .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,':,';,'<,'=,'>,'? 44 .byte '@,'A,'B,'C,'D,'E,'F,'G,'H,'I,'J,'K,'L,'M,'N,'O 45 .byte 'P,'Q,'R,'S,'T,'U,'V,'W,'X,'Y,'Z,'[,'\,'],'^,'_ 46 .byte '`,'a,'b,'c,'d,'e,'f,'g,'h,'i,'j,'k,'l,'m,'n,'o 47 .byte 'p,'q,'r,'s,'t,'u,'v,'w,'x,'y,'z,'{,'|,'},'~,127 48 .byte 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143 49 .byte 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159 50 .byte 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175 51 .byte 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191 52 .byte 192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207 53 .byte 208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223 54 .byte 224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239 55 .byte 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255 56 57 ENTRY(_doprnt, R6|R7|R8|R9|R10|R11) 58 jbr doit 59 60 strfoo: 61 clrl r4 # fix interrupt race 62 jbr strok # and try again 63 strout2: # enter here to force out r2; r0,r1 must be set 64 # do some tricks with line buffering (_IOLBF) first 65 movl fdesc,r3 66 jbc $7,16(r3),0f # not line buffered (unbuffered) 67 addl3 12(r3),8(r3),r4 # fdesc->_base+fdesc->_bufsiz 68 cmpl 4(r3),r4 # buffer full? 69 jgeq 0f # yes 70 cmpl r2,$10 # c == '\n'? 71 jeql 0f # yes 72 movb r2,*4(r3) # line buffered and not buffer full 73 incl 4(r3) # and not newline 74 clrl (r3) # just stuff it and fix _cnt 75 incl nchar # count the char 76 jbr strout # skip __flsbuf 77 0: pushr $3 # save input descriptor 78 pushl fdesc # FILE 79 pushl r2 # the char 80 calls $2,__flsbuf # please empty the buffer and handle 1 char 81 tstl r0 # successful? 82 jgeq strm1 # yes 83 jbcs $31,nchar,strm1 # turn on sign bit of nchar to signify error 84 strm1: 85 incl nchar # count the char 86 popr $3 # get input descriptor back 87 strout: # enter via bsb with (r0,r1)=input descriptor 88 movab strtab,r3 # table address 89 movq *fdesc,r4 # output descriptor 90 jbs $31,r4,strfoo # negative count is a no no 91 strok: 92 addl2 r0,nchar # we intend to move this many chars 93 /******* Start bogus movtuc workaround *****/ 94 clrl r2 95 tstl r0 96 bleq movdon 97 movlp: 98 tstl r4 99 bleq movdon 100 movzbl (r1)+,r3 101 tstb strtab[r3] 102 bneq 1f 103 mnegl $1,r2 104 decl r1 105 brb movdon 106 1: 107 movb r3,(r5)+ 108 decl r4 109 sobgtr r0,movlp 110 /******* End bogus movtuc workaround *** 111 movtuc r0,(r1),$0,(r3),r4,(r5) 112 movpsl r2 /* squirrel away condition codes */ 113 /******* End equally bogus movtuc ****/ 114 movdon: movq r4,*fdesc /* update output descriptor */ 115 subl2 r0,nchar # some chars not moved 116 jbs $vbit,r2,stresc # terminated by escape? 117 sobgeq r0,strmore # no; but out buffer might be full 118 stresc: 119 rsb 120 strmore: 121 movzbl (r1)+,r2 # one char 122 tstb strtab[r2] # translate 123 jneq strout2 # bad guy in disguise (outbuf is full) 124 incl r0 # fix the length 125 decl r1 # and the addr 126 movl $1<vbit,r2 # fake condition codes 127 rsb 128 129 errdone: 130 jbcs $31,nchar,prdone # set error bit 131 prdone: 132 movl nchar,r0 133 ret 134 135 doit: 136 movab -256(sp),sp # work space 137 movl 4(ap),r11 # addr of format string 138 movl 12(ap),fdesc # output FILE ptr 139 movl 8(ap),ap # addr of first arg 140 clrl nchar # number of chars transferred 141 loop: 142 movzwl $65535,r0 # pseudo length 143 movl r11,r1 # fmt addr 144 # comet sucks. 145 movq *fdesc,r4 146 subl3 r1,r5,r2 147 jlss lp1 148 cmpl r0,r2 149 jleq lp1 150 movl r2,r0 151 lp1: 152 # 153 bsbw strout # copy to output, stop at null or percent 154 movl r1,r11 # new fmt 155 jbc $vbit,r2,loop # if no escape, then very long fmt 156 tstb (r11)+ # escape; null or percent? 157 jeql prdone # null means end of fmt 158 159 movl sp,r5 # reset output buffer pointer 160 clrq r9 # width; flags 161 clrq r6 # lrafx,llafx 162 longorunsg: # we can ignore both of these distinctions 163 short: 164 L4a: 165 movzbl (r11)+,r0 # so capital letters can tail merge 166 L4: caseb r0,$' ,$'x-' # format char 167 L5: 168 .word space-L5 # space 169 .word fmtbad-L5 # ! 170 .word fmtbad-L5 # " 171 .word sharp-L5 # # 172 .word fmtbad-L5 # $ 173 .word fmtbad-L5 # % 174 .word fmtbad-L5 # & 175 .word fmtbad-L5 # ' 176 .word fmtbad-L5 # ( 177 .word fmtbad-L5 # ) 178 .word indir-L5 # * 179 .word plus-L5 # + 180 .word fmtbad-L5 # , 181 .word minus-L5 # - 182 .word dot-L5 # . 183 .word fmtbad-L5 # / 184 .word gnum0-L5 # 0 185 .word gnum-L5 # 1 186 .word gnum-L5 # 2 187 .word gnum-L5 # 3 188 .word gnum-L5 # 4 189 .word gnum-L5 # 5 190 .word gnum-L5 # 6 191 .word gnum-L5 # 7 192 .word gnum-L5 # 8 193 .word gnum-L5 # 9 194 .word fmtbad-L5 # : 195 .word fmtbad-L5 # ; 196 .word fmtbad-L5 # < 197 .word fmtbad-L5 # = 198 .word fmtbad-L5 # > 199 .word fmtbad-L5 # ? 200 .word fmtbad-L5 # @ 201 .word fmtbad-L5 # A 202 .word fmtbad-L5 # B 203 .word fmtbad-L5 # C 204 .word decimal-L5 # D 205 .word capital-L5 # E 206 .word fmtbad-L5 # F 207 .word capital-L5 # G 208 .word fmtbad-L5 # H 209 .word fmtbad-L5 # I 210 .word fmtbad-L5 # J 211 .word fmtbad-L5 # K 212 .word fmtbad-L5 # L 213 .word fmtbad-L5 # M 214 .word fmtbad-L5 # N 215 .word octal-L5 # O 216 .word fmtbad-L5 # P 217 .word fmtbad-L5 # Q 218 .word fmtbad-L5 # R 219 .word fmtbad-L5 # S 220 .word fmtbad-L5 # T 221 .word unsigned-L5 # U 222 .word fmtbad-L5 # V 223 .word fmtbad-L5 # W 224 .word capital-L5 # X 225 .word fmtbad-L5 # Y 226 .word fmtbad-L5 # Z 227 .word fmtbad-L5 # [ 228 .word fmtbad-L5 # \ 229 .word fmtbad-L5 # ] 230 .word fmtbad-L5 # ^ 231 .word fmtbad-L5 # _ 232 .word fmtbad-L5 # ` 233 .word fmtbad-L5 # a 234 .word fmtbad-L5 # b 235 .word charac-L5 # c 236 .word decimal-L5 # d 237 .word scien-L5 # e 238 .word float-L5 # f 239 .word general-L5 # g 240 .word short-L5 # h 241 .word fmtbad-L5 # i 242 .word fmtbad-L5 # j 243 .word fmtbad-L5 # k 244 .word longorunsg-L5 # l 245 .word fmtbad-L5 # m 246 .word fmtbad-L5 # n 247 .word octal-L5 # o 248 .word fmtbad-L5 # p 249 .word fmtbad-L5 # q 250 .word fmtbad-L5 # r 251 .word string-L5 # s 252 .word fmtbad-L5 # t 253 .word unsigned-L5 # u 254 .word fmtbad-L5 # v 255 .word fmtbad-L5 # w 256 .word hex-L5 # x 257 fmtbad: 258 movb r0,(r5)+ # print the unfound character 259 jeql errdone # dumb users who end the format with a % 260 jbr prbuf 261 capital: 262 bisl2 $1<caps,flags # note that it was capitalized 263 xorb2 $'a^'A,r0 # make it small 264 jbr L4 # and try again 265 266 string: 267 movl ndigit,r0 268 jbs $prec,flags,L20 # max length was specified 269 mnegl $1,r0 # default max length 270 L20: movl (ap)+,r2 # addr first byte 271 locc $0,r0,(r2) # find the zero at the end 272 movl r1,r5 # addr last byte +1 273 movl r2,r1 # addr first byte 274 jbr prstr 275 276 htab: .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,'a,'b,'c,'d,'e,'f 277 Htab: .byte '0,'1,'2,'3,'4,'5,'6,'7,'8,'9,'A,'B,'C,'D,'E,'F 278 279 octal: 280 movl $30,r2 # init position 281 movl $3,r3 # field width 282 movab htab,llafx # translate table 283 jbr L10 284 285 hex: 286 movl $28,r2 # init position 287 movl $4,r3 # field width 288 movab htab,llafx # translate table 289 jbc $caps,flags,L10 290 movab Htab,llafx 291 L10: mnegl r3,r6 # increment 292 clrl r1 293 addl2 $4,r5 # room for left affix (2) and slop [forced sign?] 294 movl (ap)+,r0 # fetch arg 295 L11: extzv r2,r3,r0,r1 # pull out a digit 296 movb (llafx)[r1],(r5)+ # convert to character 297 L12: acbl $0,r6,r2,L11 # continue until done 298 clrq r6 # lrafx, llafx 299 clrb (r5) # flag end 300 skpc $'0,$11,4(sp) # skip over leading zeroes 301 jbc $numsgn,flags,prn3 # easy if no left affix 302 tstl -4(ap) # original value 303 jeql prn3 # no affix on 0, for some reason 304 cmpl r3,$4 # were we doing hex or octal? 305 jneq L12a # octal 306 movb $'x,r0 307 jbc $caps,flags,L12b 308 movb $'X,r0 309 L12b: movb r0,-(r1) 310 movl $2,llafx # leading 0x for hex is an affix 311 L12a: movb $'0,-(r1) # leading zero for octal is a digit, not an affix 312 jbr prn3 # omit sign (plus, blank) massaging 313 314 unsigned: 315 lunsigned: 316 bicl2 $1<plssgn|1<blank,flags # omit sign (plus, blank) massaging 317 extzv $1,$31,(ap),r0 # right shift logical 1 bit 318 cvtlp r0,$10,(sp) # convert [n/2] to packed 319 movp $10,(sp),8(sp) # copy packed 320 addp4 $10,8(sp),$10,(sp) # 2*[n/2] in packed, at (sp) 321 blbc (ap)+,L14 # n was even 322 addp4 $1,pone,$10,(sp) # n was odd 323 jbr L14 324 325 patdec: # editpc pattern for decimal printing 326 .byte 0xAA # eo$float 10 327 .byte 0x01 # eo$end_float 328 .byte 0 # eo$end 329 330 decimal: 331 cvtlp (ap)+,$10,(sp) # 10 digits max 332 jgeq L14 333 incl llafx # minus sign is a left affix 334 L14: editpc $10,(sp),patdec,8(sp) # ascii at 8(sp); r5=end+1 335 skpc $' ,$11,8(sp) # skip leading blanks; r1=first 336 337 prnum: # r1=addr first byte, r5=addr last byte +1, llafx=size of signs 338 # -1(r1) vacant, for forced sign 339 tstl llafx 340 jneq prn3 # already some left affix, dont fuss 341 jbc $plssgn,flags,prn2 342 movb $'+,-(r1) # needs a plus sign 343 jbr prn4 344 prn2: jbc $blank,flags,prn3 345 movb $' ,-(r1) # needs a blank sign 346 prn4: incl llafx 347 prn3: jbs $prec,flags,prn1 348 movl $1,ndigit # default precision is 1 349 prn1: subl3 r1,r5,lrafx # raw width 350 subl2 llafx,lrafx # number of digits 351 subl2 lrafx,ndigit # number of leading zeroes needed 352 jleq prstr # none 353 addl2 llafx,r1 # where current digits start 354 pushl r1 # movcx gobbles registers 355 # check bounds on users who say %.300d 356 movab 32(r5)[ndigit],r2 357 subl2 fp,r2 358 jlss prn5 359 subl2 r2,ndigit 360 prn5: 361 # 362 movc3 lrafx,(r1),(r1)[ndigit] # make room in middle 363 movc5 $0,(r1),$ch.zer,ndigit,*(sp) # '0 fill 364 subl3 llafx,(sp)+,r1 # first byte addr 365 addl3 lrafx,r3,r5 # last byte addr +1 366 367 prstr: # r1=addr first byte; r5=addr last byte +1 368 # width=minimum width; llafx=len. left affix 369 # ndigit=<avail> 370 subl3 r1,r5,ndigit # raw width 371 subl3 ndigit,width,r0 # pad length 372 jleq padlno # in particular, no left padding 373 jbs $minsgn,flags,padlno 374 # extension for %0 flag causing left zero padding to field width 375 jbs $zfill,flags,padlz 376 # this bsbb needed even if %0 flag extension is removed 377 bsbb padb # blank pad on left 378 jbr padnlz 379 padlz: 380 movl llafx,r0 381 jleq padnlx # left zero pad requires left affix first 382 subl2 r0,ndigit # part of total length will be transferred 383 subl2 r0,width # and will account for part of minimum width 384 bsbw strout # left affix 385 padnlx: 386 subl3 ndigit,width,r0 # pad length 387 bsbb padz # zero pad on left 388 padnlz: 389 # end of extension for left zero padding 390 padlno: # remaining: root, possible right padding 391 subl2 ndigit,width # root reduces minimum width 392 movl ndigit,r0 # root length 393 p1: bsbw strout # transfer to output buffer 394 p3: jbc $vbit,r2,padnpct # percent sign (or null byte via %c) ? 395 decl r0 # yes; adjust count 396 movzbl (r1)+,r2 # fetch byte 397 movq *fdesc,r4 # output buffer descriptor 398 sobgeq r4,p2 # room at the out [inn] ? 399 bsbw strout2 # no; force it, then try rest 400 jbr p3 # here we go 'round the mullberry bush, ... 401 p2: movb r2,(r5)+ # hand-deposit the percent or null 402 incl nchar # count it 403 movq r4,*fdesc # store output descriptor 404 jbr p1 # what an expensive hiccup! 405 padnpct: 406 movl width,r0 # size of pad 407 jleq loop 408 bsbb padb 409 jbr loop 410 411 padz: 412 movb $'0,r2 413 jbr pad 414 padb: 415 movb $' ,r2 416 pad: 417 subl2 r0,width # pad width decreases minimum width 418 pushl r1 # save non-pad addr 419 movl r0,llafx # remember width of pad 420 subl2 r0,sp # allocate 421 movc5 $0,(r0),r2,llafx,(sp) # create pad string 422 movl llafx,r0 # length 423 movl sp,r1 # addr 424 bsbw strout 425 addl2 llafx,sp # deallocate 426 movl (sp)+,r1 # recover non-pad addr 427 rsb 428 429 pone: .byte 0x1C # packed 1 430 431 charac: 432 movl (ap)+,r0 # word containing the char 433 movb r0,(r5)+ # one byte, that's all 434 435 prbuf: 436 movl sp,r1 # addr first byte 437 jbr prstr 438 439 space: bisl2 $1<blank,flags # constant width e fmt, no plus sign 440 jbr L4a 441 sharp: bisl2 $1<numsgn,flags # 'self identifying', please 442 jbr L4a 443 plus: bisl2 $1<plssgn,flags # always print sign for floats 444 jbr L4a 445 minus: bisl2 $1<minsgn,flags # left justification, please 446 jbr L4a 447 gnum0: jbs $ndfnd,flags,gnum 448 jbs $prec,flags,gnump # ignore when reading precision 449 bisl2 $1<zfill,flags # leading zero fill, please 450 gnum: jbs $prec,flags,gnump 451 moval (width)[width],width # width *= 5; 452 movaw -ch.zer(r0)[width],width # width = 2*witdh + r0 - '0'; 453 jbr gnumd 454 gnump: moval (ndigit)[ndigit],ndigit # ndigit *= 5; 455 movaw -ch.zer(r0)[ndigit],ndigit # ndigit = 2*ndigit + r0 - '0'; 456 gnumd: bisl2 $1<ndfnd,flags # digit seen 457 jbr L4a 458 dot: clrl ndigit # start on the precision 459 bisl2 $1<prec,flags 460 bicl2 $1<ndfnd,flags 461 jbr L4a 462 indir: 463 jbs $prec,flags,in1 464 movl (ap)+,width # width specified by parameter 465 jgeq gnumd 466 xorl2 $1<minsgn,flags # parameterized left adjustment 467 mnegl width,width 468 jbr gnumd 469 in1: 470 movl (ap)+,ndigit # precision specified by paratmeter 471 jgeq gnumd 472 mnegl ndigit,ndigit 473 jbr gnumd 474 475 float: 476 jbs $prec,flags,float1 477 movl $6,ndigit # default # digits to right of decpt. 478 float1: bsbw fltcvt 479 addl3 exp,ndigit,r7 480 movl r7,r6 # for later "underflow" checking 481 bgeq fxplrd 482 clrl r7 # poor programmer planning 483 fxplrd: cmpl r7,$31 # expressible in packed decimal? 484 bleq fnarro # yes 485 movl $31,r7 486 fnarro: subl3 $17,r7,r0 # where to round 487 ashp r0,$17,(sp),$5,r7,16(sp) # do it 488 bvc fnovfl 489 # band-aid for microcode error (spurious overflow) 490 # clrl r0 # assume even length result 491 # jlbc r7,fleven # right 492 # movl $4,r0 # odd length result 493 #fleven: cmpv r0,$4,16(sp),$0 # top digit zero iff true overflow 494 # bneq fnovfl 495 # end band-aid 496 aobleq $0,r6,fnovfl # if "underflow" then jump 497 movl r7,r0 498 incl exp 499 incl r7 500 ashp r0,$1,pone,$0,r7,16(sp) 501 ashl $-1,r7,r0 # displ to last byte 502 bisb2 sign,16(sp)[r0] # insert sign 503 fnovfl: 504 movab 16(sp),r1 # packed source 505 movl r7,r6 # packed length 506 pushab prnum # goto prnum after fall-through call to fedit 507 508 509 # enter via bsb 510 # r1=addr of packed source 511 # 16(r1) used to unpack source 512 # 48(r1) used to construct pattern to unpack source 513 # 48(r1) used to hold result 514 # r6=length of packed source (destroyed) 515 # exp=# digits to left of decimal point (destroyed) 516 # ndigit=# digits to right of decimal point (destroyed) 517 # sign=1 if negative, 0 otherwise 518 # stack will be used for work space for pattern and unpacked source 519 # exits with 520 # r1=addr of punctuated result 521 # r5=addr of last byte +1 522 # llafx=1 if minus sign inserted, 0 otherwise 523 fedit: 524 pushab 48(r1) # save result addr 525 movab 48(r1),r3 # pattern addr 526 movb $0x03,(r3)+ # eo$set_signif 527 movc5 $0,(r1),$0x91,r6,(r3) # eo$move 1 528 clrb (r3) # eo$end 529 editpc r6,(r1),48(r1),16(r1) # unpack 'em all 530 subl3 r6,r5,r1 # addr unpacked source 531 movl (sp),r3 # punctuated output placed here 532 clrl llafx 533 jlbc sign,f1 534 movb $'-,(r3)+ # negative 535 incl llafx 536 f1: movl exp,r0 537 jgtr f2 538 movb $'0,(r3)+ # must have digit before decimal point 539 jbr f3 540 f2: cmpl r0,r6 # limit on packed length 541 jleq f4 542 movl r6,r0 543 f4: subl2 r0,r6 # eat some digits 544 subl2 r0,exp # from the exponent 545 movc3 r0,(r1),(r3) # (most of the) digits to left of decimal point 546 movl exp,r0 # need any more? 547 jleq f3 548 movc5 $0,(r1),$'0,r0,(r3) # '0 fill 549 f3: movl ndigit,r0 # # digits to right of decimal point 550 jgtr f5 551 jbs $numsgn,flags,f5 # no decimal point unless forced 552 jbcs $dpflag,flags,f6 # no decimal point 553 f5: movb $'.,(r3)+ # the decimal point 554 f6: mnegl exp,r0 # "leading" zeroes to right of decimal point 555 jleq f9 556 cmpl r0,ndigit # cant exceed this many 557 jleq fa 558 movl ndigit,r0 559 fa: subl2 r0,ndigit 560 movc5 $0,(r1),$'0,r0,(r3) 561 f9: movl ndigit,r0 562 cmpl r0,r6 # limit on packed length 563 jleq f7 564 movl r6,r0 565 f7: subl2 r0,ndigit # eat some digits from the fraction 566 movc3 r0,(r1),(r3) # (most of the) digits to right of decimal point 567 movl ndigit,r0 # need any more? 568 jleq f8 569 # check bounds on users who say %.300f 570 movab 32(r3)[r0],r2 571 subl2 fp,r2 572 jlss fb 573 subl2 r2,r0 # truncate, willy-nilly 574 movl r0,ndigit # and no more digits later, either 575 fb: 576 # 577 subl2 r0,ndigit # eat some digits from the fraction 578 movc5 $0,(r1),$'0,r0,(r3) # '0 fill 579 f8: movl r3,r5 # addr last byte +1 580 popr $1<1 # [movl (sp)+,r1] addr first byte 581 rsb 582 583 patexp: .byte 0x03 # eo$set_signif 584 .byte 0x44,'e # eo$insert 'e 585 .byte 0x42,'+ # eo$load_plus '+ 586 .byte 0x04 # eo$store_sign 587 .byte 0x92 # eo$move 2 588 .byte 0 # eo$end 589 590 scien: 591 incl ndigit 592 jbs $prec,flags,L23 593 movl $7,ndigit 594 L23: bsbw fltcvt # get packed digits 595 movl ndigit,r7 596 cmpl r7,$31 # expressible in packed decimal? 597 jleq snarro # yes 598 movl $31,r7 599 snarro: subl3 $17,r7,r0 # rounding position 600 ashp r0,$17,(sp),$5,r7,16(sp) # shift and round 601 bvc snovfl 602 # band-aid for microcode error (spurious overflow) 603 # clrl r0 # assume even length result 604 # jlbc ndigit,sceven # right 605 # movl $4,r0 # odd length result 606 #sceven: cmpv r0,$4,16(sp),$0 # top digit zero iff true overflow 607 # bneq snovfl 608 # end band-aid 609 incl exp # rounding overflowed to 100... 610 subl3 $1,r7,r0 611 ashp r0,$1,pone,$0,r7,16(sp) 612 ashl $-1,r7,r0 # displ to last byte 613 bisb2 sign,16(sp)[r0] # insert sign 614 snovfl: 615 jbs $gflag,flags,gfmt # %g format 616 movab 16(sp),r1 617 bsbb eedit 618 eexp: 619 movl r1,r6 # save fwa from destruction by cvtlp 620 subl3 $1,sexp,r0 # 1P exponent 621 cvtlp r0,$2,(sp) # packed 622 editpc $2,(sp),patexp,(r5) 623 movl r6,r1 # fwa 624 jbc $caps,flags,prnum 625 xorb2 $'e^'E,-4(r5) 626 jbr prnum 627 628 eedit: 629 movl r7,r6 # packed length 630 decl ndigit # 1 digit before decimal point 631 movl exp,sexp # save from destruction 632 movl $1,exp # and pretend 633 jbr fedit 634 635 gfmt: 636 addl3 $3,exp,r0 # exp is 1 more than e 637 jlss gfmte # (e+1)+3<0, e+4<=-1, e<=-5 638 subl2 $3,r0 # exp [==(e+1)] 639 cmpl r0,ndigit 640 jgtr gfmte # e+1>n, e>=n 641 gfmtf: 642 movl r7,r6 643 subl2 r0,ndigit # n-e-1 644 movab 16(sp),r1 645 bsbw fedit 646 g1: jbs $numsgn,flags,g2 647 jbs $dpflag,flags,g2 # dont strip if no decimal point 648 g3: cmpb -(r5),$'0 # strip trailing zeroes 649 jeql g3 650 cmpb (r5),$'. # and trailing decimal point 651 jeql g2 652 incl r5 653 g2: jbc $gflag,flags,eexp 654 jbr prnum 655 gfmte: 656 movab 16(sp),r1 # packed source 657 bsbw eedit 658 jbsc $gflag,flags,g1 # gflag now means "use %f" [hence no exponent] 659 660 general: 661 jbs $prec,flags,gn1 662 movl $6,ndigit # default precision is 6 significant digits 663 gn1: tstl ndigit # cannot allow precision of 0 664 jgtr gn2 665 movl $1,ndigit # change 0 to 1, willy-nilly 666 gn2: jbcs $gflag,flags,L23 667 jbr L23 # safety net 668 669 # convert double-floating at (ap) to 17-digit packed at (sp), 670 # set 'sign' and 'exp', advance ap. 671 fltcvt: 672 clrb sign 673 movd (ap)+,r5 674 jeql fzero 675 bgtr fpos 676 mnegd r5,r5 677 incb sign 678 fpos: 679 extzv $7,$8,r5,r2 # exponent of 2 680 movab -0200(r2),r2 # unbias 681 mull2 $59,r2 # 59/196: 3rd convergent continued frac of log10(2) 682 jlss eneg 683 movab 196(r2),r2 684 eneg: 685 movab -98(r2),r2 686 divl2 $196,r2 687 bsbw expten 688 cmpd r0,r5 689 bgtr ceil 690 incl r2 691 ceil: movl r2,exp 692 mnegl r2,r2 693 cmpl r2,$29 # 10^(29+9) is all we can handle 694 bleq getman 695 muld2 ten16,r5 696 subl2 $16,r2 697 getman: addl2 $9,r2 # -ceil(log10(x)) + 9 698 jsb expten 699 emodd r0,r4,r5,r0,r5 # (r0+r4)*r5; r0=int, r5=frac 700 fz1: cvtlp r0,$9,16(sp) # leading 9 digits 701 ashp $8,$9,16(sp),$0,$17,4(sp) # as top 9 of 17 702 emodd ten8,$0,r5,r0,r5 703 cvtlp r0,$8,16(sp) # trailing 8 digits 704 # if precision >= 17, must round here 705 movl ndigit,r7 # so figure out what precision is 706 pushab scien 707 cmpl (sp)+,(sp) 708 jleq gm1 # who called us? 709 addl2 exp,r7 # float; adjust for exponent 710 gm1: cmpl r7,$17 711 jlss gm2 712 cmpd r5,$0d0.5 # must round here; check fraction 713 jlss gm2 714 bisb2 $0x10,8+4(sp) # increment l.s. digit 715 gm2: # end of "round here" code 716 addp4 $8,16(sp),$17,4(sp) # combine leading and trailing 717 bisb2 sign,12(sp) # and insert sign 718 rsb 719 fzero: clrl r0 720 movl $1,exp # 0.000e+00 and 0.000 rather than 0.000e-01 and .000 721 jbr fz1 722 723 .align 2 724 lsb: .long 0x00010000 # lsb in the crazy floating-point format 725 726 # return 10^r2 as a double float in r0||r1 and 8 extra bits of precision in r4 727 # preserve r2, r5||r6 728 expten: 729 movd $0d1.0,r0 # begin computing 10^exp10 730 clrl r4 # bit counter 731 movad ten1,r3 # table address 732 tstl r2 733 bgeq e10lp 734 mnegl r2,r2 # get absolute value 735 jbss $6,r2,e10lp # flag as negative 736 e10lp: jbc r4,r2,el1 # want this power? 737 muld2 (r3),r0 # yes 738 el1: addl2 $8,r3 # advance to next power 739 aobleq $5,r4,e10lp # through 10^32 740 jbcc $6,r2,el2 # correct for negative exponent 741 divd3 r0,$0d1.0,r0 # by taking reciprocal 742 cmpl $28,r2 743 jneq enm28 744 addl2 lsb,r1 # 10**-28 needs lsb incremented 745 enm28: mnegl r2,r2 # original exponent of 10 746 el2: addl3 $5*8,r2,r3 # negative bit positions are illegal? 747 jbc r3,xlsbh-5,eoklsb 748 subl2 lsb,r1 # lsb was too high 749 eoklsb: 750 movzbl xprec[r2],r4 # 8 extra bits 751 rsb 752 753 # powers of ten 754 .align 2 755 ten1: .word 0x4220,0,0,0 756 ten2: .word 0x43c8,0,0,0 757 ten4: .word 0x471c,0x4000,0,0 758 ten8: .word 0x4dbe,0xbc20,0,0 759 ten16: .word 0x5b0e,0x1bc9,0xbf04,0 760 ten32: .word 0x759d,0xc5ad,0xa82b,0x70b6 761 762 # whether lsb is too high or not 763 .byte 1:0,1:0,1:0,1:0,1:1,1:0,1:1,1:0 # -40 thru -33 764 .byte 1:0,1:1,1:0,1:0,1:0,1:0,1:1,1:0 # -32 thru -25 765 .byte 1:0,1:0,1:1,1:1,1:1,1:1,1:0,1:0 # -24 thru -17 766 .byte 1:0,1:1,1:0,1:0,1:1,1:1,1:1,1:1 # -16 thru -9 767 .byte 1:1,1:1,1:1,1:0,1:0,1:0,1:0,1:1 # -8 thru -1 768 xlsbh: 769 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 0 thru 7 770 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 8 thru 15 771 .byte 1:0,1:0,1:0,1:0,1:0,1:0,1:0,1:0 # 16 thru 23 772 .byte 1:0,1:1,1:1,1:0,1:1,1:1,1:1,1:1 # 24 thru 31 773 .byte 1:1,1:1,1:1,1:1,1:1,1:1,1:1 # 32 thru 38 774 775 # bytes of extra precision 776 .byte 0x56,0x76,0xd3,0x88,0xb5,0x62 # -38 thru -33 777 .byte 0xba,0xf5,0x32,0x3e,0x0e,0x48,0xdb,0x51 # -32 thru -25 778 .byte 0x53,0x27,0xb1,0xef,0xeb,0xa5,0x07,0x49 # -24 thru -17 779 .byte 0x5b,0xd9,0x0f,0x13,0xcd,0xff,0xbf,0x97 # -16 thru -9 780 .byte 0xfd,0xbc,0xb6,0x23,0x2c,0x3b,0x0a,0xcd # -8 thru -1 781 xprec: 782 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 0 thru 7 783 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 8 thru 15 784 .byte 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 # 16 thru 23 785 .byte 0x00,0xa0,0xc8,0x3a,0x84,0xe4,0xdc,0x92 # 24 thru 31 786 .byte 0x9b,0x00,0xc0,0x58,0xae,0x18,0xef # 32 thru 38 787