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.TOC "GFLT DOUBLE PRECISION ARITHMETIC" .IF/MODEL.B .IF/EXTEXP .DCODE 102: R, B/0, J/EDFLOT ;EFAD 103: R, B/2, J/EDFLOT ;EFSB 106: R, B/4, J/EDFLOT ;EFMP 107: R, B/6, J/EDFLOT ;EFDV .UCODE =0****00**0* EDFLOT: VMA_VMA+1, LOAD ARX, MQ_0.S, CALL [XFERW] FM[E0]_AR, ARX_ARX*2, B DISP ;mem high to E0, do instruction = =000 EDFL1: SKP AR0, CALL [ISOEXP] ;save mem high word in E0. FM[T2]_AR, J/EF1 ;save mem exp in T2. AR_-AR LONG ;subtract now same as add. FM[E0]_AR, J/EDFL1 ;save "positive" exponent =100 SKP AR0, CALL [ISOEXP] ;isolate mem exp in AR. BR/AR, GEN ARX, SKP AD NE, ;start test for sticky bits. J/EFMP =110 BR/AR, GEN AR, SKP AD0, ;save mem high in br. CALL [ISOEXP] ;get mem exp FM[T2]_AR, AR_0S, J/EFDV0 ;save mem exp in T2. No sticky bits. =0 EF1: AR_AC0, SKP AD0, CALL [ISOEXP] ;get AC op FM[E1]_AR, BR/AR ;save AC exp in E1 ;Now have positive mem exponent in T2, pos AC exp in E1. ;Save larger exp in T2 and exp diff if less than 340 in SC. [AR]_[AR]*FM[T2], AD/A-B, ;AR gets exp diff. SKP AD0 ;AR get exp diff, BRX gets exp. =00 SC_#, #/3, CALL [EXPDIF] ;test for exp diff >72. BR/AR, J/EF3A ;mem op larger. AR_BR, J/EF5 ;restore exp to AR. [AR]_FM[E1], CLR FE, J/ACNORM ;exp diff too large, norm AC op. =00 EF3A: AR_-BR, SC_#, #/3, CALL [EXPDIF];mem larger, get positive diff. =10 AR_BR, J/EF3B ;restore exponent to AR. [AR]_FM[T2], CLR FE, J/MEMNRM ;exp diff > 72. norm mem op. EF3B: AR_AR*8 ;move exp difference into AR0-8. FE_AR0-8, ;mem larger, op doable. AR_AC0 ;save smaller AC op in T0,T1 =0 FM[T0]_AR, CALL [EF5B] FM[T1]_AR [AR]_FM[E0] ;save larger mem op in AC0,AC1 AC0_AR, AR_ARX AC1_AR, J/EF5A ;all set to shift and add. EF5: AR_AR*8 ;move exp difference into AR0-8. FE_AR0-8, [AR]_FM[E0] ;smaller mem op to T0,T1 FM[T0]_AR, AR_ARX =0 FM[T1]_AR, CALL [EF5B] AC1_AR ;we expect AC1*2 to be saved. [AR]_FM[E1] ;save larger AC exp in T2 FM[T2]_AR, J/EF5A EF5B: AR_AC1*2, RETURN1 ;EXPDIF determines if the exponent difference is too large-ie >110 oct. ;The largest allowed value for shifting is 72 decimal. This is 110 octal. ;Since the exponent is in AR1-11, 110 octal has the value 11 in AR1-8. ;It expects the exponent difference in AR0-8. ;It uses AR0-8 and the BR. ;Returns 2 if the difference is ok (<=110). ;Returns 3 if the difference is too large (>110). EXPDIF: BR/AR, CLR AR ;zero all of those bits. AR0-8_#, #/10 ;put in 100 in AR0-11. GEN AR-BR, SKP AD0, RETURN2 ;<max diff>-<actual diff> ;We now have: ; AC0 / larger op high ; AC1 / larger op low ; T0 / smaller op high ; T1 / smaller op low ; T2 / larger exponent ; FE / exp difference ;We must now sign extend both high ops. =0 EF5A: AR_AC0, SKP AD0, CALL [SGNEXT] ;get larger high op AC0_AR ;save larger extended op in AC0 =0 [AR]_FM[T0], SKP AD0, ;get smaller high op CALL [SGNEXT] ; and sign extend into AR1-11. FM[T0]_AR ;save smaller extended op in T0 ;We are now set to shift the smaller op to align it with the larger op. [AR]_FM[T1] [AR]_FM[T0], ARX_AR, SC_FE ;move diff to SC for next line. SC_#-SC, #/36., SKP SCAD0 =0 ARX_AR, AR_SIGN, J/EF10 ;FE < 37. BR/AR, BRX/ARX, SC_FE AR_SIGN, ARX_AR SC_#-SC, #/72. ARX_SHIFT ;high is sign, low is sign,,high. =01 AR_BR LONG, BR/AR, BRX/ARX, ;save new stuff in BR long. CALL [EF12] ;MQ gets lowest word. FM[E1]_AR ;save sticky bits. AR_AC1, J/EF11 ;now prepare to add. EF10: AR_SHIFT, [ARX]_FM[T1] ;shift high op, load low word. BR/AR, [AR]_FM[T0] ;shift low op, load high word. AR_ARX (AD), ARX_SHIFT ;get shifted low word into ARX. =01 BRX/ARX, CLR ARX, CALL [EF12] ;save low word, shift end bits. FM[E1]_AR ;save sticky bits. (word 4 of sum). AR_AC1, J/EF11 ;prepare to add. BR/AR, BRX/ARX, AR_AC1 ;get larger op in AR,ARX EF11: ARX_AR, AR_AC0, FE_#, #/0 ;smaller op in BR,BRX AR_AR+BR, ARX/ADX, SC_#, #/3, ;operation done, now normalize. NORM, J/ENORM EF12: MQ_SHIFT, AR_ARX (AD), CLR ARX,J/SHIFT .IF/GFTCNV ;[273] EF12A: AR_SHIFT, RETURN10 .ENDIF/GFTCNV ;[273]

.TOC "GFLT MULTIPLY" =0 EFMP: CLR AR, J/EFMP1 ;mem low op is zero, no sticky bits. AR_AC1*2, SKP AD NE ;is AC low op non-zero as well ? =0 CLR AR ;yes, no sticky bits today. EFMP1: FM[E1]_AR, AR_0S ;set sticky bits. AR0-8_#, #/200 ;subtract 200. BR/AR, AR_BR ;swap around exp and 2000. AR_AR-BR, CLR SC ;done, and SC is cleared. =0 BR/AR, AR_AC0, SKP AD0, ;save exp-2000 in BR. CALL [ISOEXP] ;get AC high and isolate exp. AR_AR+BR ;add exponents together. FM[T2]_AR ;and store the sum in T2. =0 [AR]_FM[E0], SKP AD0, ;get mem high op sign extended. CALL [SGNEXT] FE_#, #/-18. ; BR/AR, BRX/ARX, AR_AC1 ;move mem ops to BR!BRX. =000 MQ_AR, AR_0S, ARX_0S, ;multiply by low word. CALL [MULREE] =100 AR_AR+BR LONG ;low sign was set, add results. =110 MQ_AR, AR_AC0, FE_#, #/-13., ;now continue with high part. SKP AD0, CALL [SGNEXT] ;sign extend the ac high op. FM[T0]_AR ;save sign extended AC op. ; SKP AR0 ;test sign bit to adjust FE. =0 EFMPP1: MQ_AR, AR_MQ, J/EFMPP2 ;swap AR+MQ. FE_FE+1, J/EFMPP1 ;inc the FE if number is neg. =000 EFMPP2: AD/0S, FE_FE+1, DISP/MUL, ;now multiply by the high word. MQ/MQ*.25, CALL [MULP] ;Since our last multiply step used 2 signs bits instead of a sign bit ;and the MSB, our answer is too low by a power of two for positive numbers ;and too low by a power of 4 for negative numbers. =100 (AR+ARX+MQ)*2, J/EFMPP3 ;try this correction factor. =101 (AR+ARX+MQ)*.25, J/EFMPP3 ;shouldn't ever get here. =110 (AR+ARX+MQ)*2 ;and this for postive numbers. = EFMPP3: BR_AR LONG, AR_0.C, ARX_1S ;result to BR!BRX. Build mask. =01 SC_#, #/10., ;load SC with shift count. CALL [SHIFT] ;Now have mask of 0,,1777 AR_BR LONG, BR_AR LONG ;mask to BR, result TO AR!ARX. MQ_MQ*BR, AD/ANDCB ;clear the last 10 MQ bits. GEN AR, SC_#, #/3, ;generate NORM bits. NORM, J/ENORM ;conditions set for EE norm.

.TOC "GFLT DIVIDE" EFDV0: FM[E1]_AR ;no sticky bits on divide. =0 AR_BR, SKP AD0, CALL [SGNEXT] ;sign extend mem high. GEN AR*AC0, AD/XOR, SKP AD0, ;determine sign of result. BR_AR LONG ;mem op to BR!BRX. =000 AR_AC1*2, CALL [EFDV1] ;start division. SR_1, AR_AC1*2, CALL [EFDV1] ;note result if negative. =011 AC1_AR, AR_MQ, ARL/AD, FE_FE+1, ;set step count to 35-2. MQ_0.M, CALL [DIV+] =101 AC1_AR, AR_MQ, ARL/AD, FE_FE+1, MQ_0.M, CALL [DIV-] =111 CLR AR, CLR FE ;exp must be adjusted- AR0-8_#, #/200 ; it is currently 2000 too low [AR]_[AR]*FM[T2], AD/A+B ;add in the correction. FM[T2]_AR ;store the corrected exp in T2. AR_AC1, ARX/MQ, SC_#, #/3, ;get answer ready for norm. NORM, J/ENORM =00 EFDV1: ARX_AR, AR_AC0, SKP AD0, FE_#, ;AC low*2 to ARX, AC high to AR. #/23., CALL [EDVCHK] =10 SKP BR0, J/DDVSUB SET FL NO DIV, J/IFNOP ;no division this time. =0 EDVCHK: MQ_AR, J/EDVCH1 ;go to an even address. AR_-AR LONG, J/EDVCHK ;make ac op positive. =0 EDVCH1: SKP AR0, CALL [ISOEXP] ;op saved in MQ, get exp in AR. [AR]_[AR]*FM[T2], AD/A-B, ;subtract exponents. SKP AD0 ;did this cause an underflow ? =0 SET SR2 ;no, let SR2 denote this. EDVCH2: FM[T2]_AR ;yes, save exponent in T2 for ENORM. =0 EDVCH3: AR_MQ, SKP AD0, CALL [SGNEXT] ;now sign extend the op. SKP BR0, MQ_0.M, J/FDVCK1

.TOC "GFLT NORMALIZATION" ;Normalization is done here. ; The are 8 addresses the can be reached when doing a ; NORM dispatch. The following table describes the ; dispatching and how to normalize the fraction and ; exponent. ; ; =000 AR=0 AR is zero, check ARX,MQ ; =001 AR00=1 sign bit on, complement ; =010 MSB in AR 1-6 shf 4 rt.(a guess) ; =011 MSB in AR07 sht 2 rt. ; =100 MSB in AR08 sht 3 rt. ; =101 MSB in AR09 right on! ; =110 MSB in AR10 sht 1 lf. ; =111 MSB in AR 11-35 sht 4 lf.(a guess) ; ;The normalization routine for double precision assumes that ; the exponent can be found in the FE. As it goes through ; the normalization process, it adjusts the fraction and ; the FE by the correct amounts to normalize the number. ; In GFLT numbers, the exponent may not fit ; into the FE, so it has to be saved in an accumulator. ; However, if one assumes initially that the exponent is ; zero and that it is in the FE, then the same normalization ; algorithm can be used as in double precision numbers ; with the realization that at the end of the normalization ; process the FE contains the correction (EC) that must be ; added into the saved exponent (ES) to produce a 'bit-9' ; normalized number. Once this correction value is obtained, ; the 'bit-12' normalized exponent (EN) is given by ; EN = ES + EC + 3 MEMNRM: FM[T2]_AR ;save larger exponent. [AR]_FM[E0], SKP AD0, J/ACNRM1 ;get high word, sign extend it ACNORM: FM[T2]_AR ;save larger exponent. AR_AC1*2, CLR FE ;get low word*2 into AR. ARX_AR, AR_AC0, SKP AD0 ;get high word, sign extend it. =0 ACNRM1: [AR]_[AR]*FM[EXPMSK], AD/AND, ;sign extend with 0's. NORM, J/ENORM [AR]_[AR]*FM[EXPMSK], AD/ORCB, ;sign extend with 1's. NORM ;fall into the normalize routine. =000 ENORM: SKP ARX+MQ NE, SC_#, #/35., ;AR=0,check ARX,+MQ. J/ENZERO BR/AR, BRX/ARX, AR_MQ COMP, ;result neg, complement. SET SR3, J/ENNEG ;flag negative seen. AR_AR*.25 LONG, MQ_MQ*.25, ;MSB in AR 1-6. FE_FE+#, #/4, J/ENHI AR_AR*.25 LONG, FE_FE+#, ;MSB in AR07. #/2, J/EROUND ; AR_AR*.5 LONG, FE_FE+1 ;MSB in AR08. EROUND: BR_AR LONG, AR+MQ_0.S, ;MSB in AR09, where we want it. J/ERND1 ;put result in BR!BRX. (AR+ARX+MQ)*2, FE_FE-1, ;MSB in AR10. J/EROUND AR_SHIFT, FE_FE-SC ;MSB somewhere in AR 11-35. ENSHFT: BR/AR, AR_ARX, ARX/MQ ;shift everyone. MQ_SHIFT, AR_ARX (ADX), CLR ARX MQ_SHIFT, ARX/MQ, AR_BR, ;go aroung again. SC_#, #/10., NORM, J/ENORM ENNEG: GEN E1, SKP AD NE ;any sticky bits left around? =0 AR_AR+1, SKP CRY0, J/ENNEG1 ;no, 2's comp MQ. MQ_AR, AR_BR COMP, ARX_BRX COMP, NORM, J/ENORM ;one's complement to finish. =0 ENNEG1: MQ_AR, AR_BR COMP, ARX_BRX COMP, NORM, J/ENORM ;one's complement to finish. MQ_AR, AR_-BR, ARX/ADX, ;carry happened, do two's comp. NORM, J/ENORM ENHI: (AR+ARX+MQ)*.25, J/ENTRY ;go try again after setting SC. =0 ENZERO: SR_0, AR_0S, ARX_0S, J/DBLST ;result = 0, store in AC,AC+1. AR_SHIFT, FE_FE-SC, J/ENSHFT ;not zero, try next 35 bits. ERND1: ARX_2 ;build rounding constant. ARX_ARX*4 ;gen a 10 in the ARX for rounding. AR_AR+BR, ARX/ADX, NORM ;do the rounding and test norm. =110 AR_AR*.5 LONG, FE_FE+1 ;rounding blew norm, correct it. ; When we get here the number is 'bit-9' normalized ; in the AR,ARX. Add the FE + 3 to the exponent ; saved in T2. ; At this point the Extended Exponent must be put ; into the AR after everything is shifted right 3 bits. ; The double precision norm routine does this by: ; EXP_FE TST, SR DISP, CLR MQ, BRX/ARX, ARX_1 ERND2: AR_AR*.25 LONG, ;shift everything 2 bits right. MQ_MQ*.25, ; " " " SC_#, #/3 ;add in correction to FE. AR_AR*.5 LONG, ;now shift the final bit position. SC_FE+SC ;total exponent correction. BR/AR, BRX/ARX, CLR AR ;save answer in BR,BRX. EXP_SC.MS ;get exp corr in AR. ARX_AR, AR_SIGN, ;get exp into ARX 1-8. SC_#,#/33. ;prepare to shift 3 places. ARX_SHIFT, ;move exponent into ARX 1-11. [AR]_FM[EXPMSK] ;prepare to build mask in AR. AR0-8_#, #/400 ;include AR00 in EXPMSK==>400077,,-1 AR_AR*BR, AD/AND, ;zero AR1-11 to make room for exp. SC_#, #/35. ; I am sure a few lines of code can be saved around here. [AR]_FM[T2], BR/AR ;save high word in BR, load larger exp. AR_BR, BR/AR ;swap around so we can add. AR_ARX+BR, BR/AR, ;have final exponent, check for problems. SC_#,#/0 SH DISP ;any exponent problems ? =0011 ARX_AR, SC_#, #/35., ; no problems. J/ENFNL1 ENFNL0: ARX_AR, SC_#, #/35., ; no problems. J/ENFNL1 SET FLOV, J/EEOV ; an overflow occurred. SR DISP ;floating underflow - is it real ? =1101 ;test SR2. SET FXU, J/EEOV ;yes, it is a real underflow. SET FLOV ;no, GFDV saw an overflow before. EEOV: P_P AND #, #/37, ;turn off AR00. J/ENFNL0 ENFNL1: AR_ARX*BR, AD/OR ;AR now has high word, BRX has low. ARX_1, MQ_0.M, SR DISP ;incase negation of lower word needed. =10 AC0_AR, AR_SHIFT, ;store high word, ARX_BRX, ;move low word to ARX. I FETCH, J/STD1 ;prepare to store low word and exit. ARX_ARX*BRX, AD/ANDCA, ; clear rounding bit. SR_0,J/CDBLST ;negate result and store double result. CDBLST: AR_-AR LONG, J/DBLST ENTRY: SC_#, #/3, GEN AR, NORM, J/ENORM; go normalize again.

.TOC "GFLT TO INTEGER CONVERSION" .IF/GFTCNV ;[273] ;ETXIX routine is used when converting extended exponent data to ;single/double precision integers with rounding/truncation. ;This routine assumes that the AR/ARX contain the extended exponent ;data. It also assumes that the maximum exponent value + 1 of either ;36 or 70 (decimal) are already in the FE. This is the positive exponent ;maximum; the code adjusts for the fact that a negative number can have ;an exponent one greater than a positive number. ;It uses all of the registers in the EBOX and returns 4 if the ;result is positive and returns 5 if the result is negative ;with the AR/ARX containing the double word integer. It is the ;responsibility of the calling routine to determine whether ;rounding or truncation should be performed and how many words ;to store. ETXIX: ARX_ARX*2 ;get low word*2 into ARX. =0 MQ_AR, SKP AR0, ; get a positive exp in AR. CALL [ISOEXP] CLR AR, BR/AR ;clear extraneous bits, save exp. AR0-8_#, #/200 ;test for positive exp. GEN AR+BR, SKP AD0, ;skip on positive exponent(sum has AD0 on). AR_0.M ;so exponent test has a clean register. =0 MEM/ARL IND, CLR/AR+ARX,;exponent must be positive. RETURN4 ;return to caller. AR0-8_#, #/212, J/ET1 ;start range check of positive exponent ;At this point the exponent is in BR 1-11 and it is positive. ;Now we must determine if it is a small enough positive number ;to make the conversion to integer meaningful. ET1: GEN AR-BR, SKP AD0 ;do the exponent test. =0 AR_BR*4, J/ET2 ;exp fits in AR0-8, now for final test! SET AROV, I FETCH, J/NOP;exponent out of range. ET2: AR_AR*2 ;finish moving exponent into AR0-8. SC_AR0-8, GEN MQ, ;exponent to SC. SKP AD0 ;max neg exponent is 1 gtr than max pos exp. =0 ET2A: AR_MQ, GEN FE-SC, ;shift low word into ARX00-34, caller SKP SCAD0, ;put max exponent+1 in FE. range check. J/ET2B FE_FE+1, J/ET2A ;max neg exp is 1 gtr than max pos exp. =0 ET2B: FE_SC, J/ET3 ;save exp in FE. SET AROV, I FETCH, J/NOP;exponent is too large. ET3: SC_#, #/12. ;prepare to map AR12 into AR00. ;We now have the high word in the AR and ;the low word*2 in the ARX. The SC has 12 (dec) to let the ;shifter strip off the sign and exponent of the high word. AR_SIGN, MQ_SHIFT ;put high 36 integer bits into MQ. AR_ARX, BR/AR, CLR ARX ;generate low 36 integer bits and AR_BR, ARX/MQ, MQ_SHIFT,; put in MQ. High bits to ARX. SC_FE-#, #/36., ;check the size of the exponent. SKP SCAD0 ;if exp<36. then high result is sign. =0 GEN SC, SKP SCAD NE, ;is exponent gtr or geq to 36 ? J/ET3A SC_#+SC, #/37., J/ET5 ;exponent less than 36. =0 ET3A: (AR+ARX+MQ)*2, J/ET3B ;must shift left 1 bit. BRX/ARX, SC_#+SC, #/1, ;adjust exp, save low word in BRX. J/ET4 ET3B: BR_AR LONG, AR_ARX, ;high and low to BR!BRX SC_#, #/35., ;get a good exponent for final shifting. ARX/MQ, J/ET4A ;rest of fraction to ARX. ET4: AR_ARX (AD), ARX/MQ, ;exp gtr 36. High result has integer bits. MQ_SHIFT ;high result to MQ. AR_MQ, ARX_SHIFT ;put integer bits into ARX. BR_AR LONG, AR_ARX (AD),;now compute fraction. CLR ARX ;low integer to AR, pad with zeros in ARX. ET4A: AR_BR LONG, MQ_SHIFT, ;restore integer to AR!ARX, fraction to MQ. SC_#, #/35., ;low word must have bit 0 same as high. SKP AD0, RET[4] ; and return on sign of integer. =01 ET5: FM[T0]_AR, AR_ARX (AD), ;sign is high 36 bit result. Save in T0. ARX/MQ, ;high 36 bits of frac to AR, low 23 to ARX. MQ_SHIFT, ;low integer result to MQ. CALL [SHIFT] ;high half of fraction to AR. ;Now we have the high 36 bits of mantissa in AR, the low 23 bits if mantissa ;in the ARX, the high 36 bit result (the sign bits) in T0 and the low 36 bit ;result in the MQ. Now we compute the fraction to store. BR/AR, AR_ARX, CLR ARX ;high frac to BR. Now gen low fraction bits. ARX_SHIFT, ;low fraction bits to ARX. SC_#, #/35. ;low word must have same sign as high. GEN ARX*BR, AD/OR, ;gen composite OR of fraction into 1 word. MQ_AD, ;put this funny fraction in the MQ. ARX/MQ ;low integer result to ARX. [AR]_FM[T0], SKP AD0, ;get high result (Sign) back in AR. RET[4] ;and return to caller. .ENDIF/GFTCNV ;[273]

;ISOEXP will isolate the exponent in an extended exponent data word. ;It will return the positive representation of the exponent. ;Call with AR containing high order word with "SKP AR0" to do ;correct things with one's complemented exponent in negative numbers. ;It returns 1 with the positive exponent in the AR. =0 ISOEXP: [AR]_[AR]*FM[EXPMSK],AD/ANDCB,RET[1] ;isolate pos exp in AR1-11. [AR]_[AR]*FM[EXPMSK],AD/NOR,RET[1] ;isolate neg exp in AR1-11. ;SGNEXT will extend the sign bit of the AR into AR1-11. Call with ;SKP AR0 so the correct actions are taken for negative numbers. ;It will do a return 1 with either ones or zeroes in AR1-11. =0 SGNEXT: [AR]_[AR]*FM[EXPMSK], AD/AND, RET[1] ;extend 0s into AR1-11. [AR]_[AR]*FM[EXPMSK], AD/ORCB, RET[1] ;extend ones into AR1-11. ;OVTEST will determine if the high order word of a double integer, ;as stored in the AR is all sign bits, ie either it is all zeroes ;or all ones. The call is via "GEN AR, SKP AD NE, J/OVTEST". ;It assumes that the double integer is in the AR/ARX and the SC ;contains 35 decimal. ;OVTEST will store the ARX*.5 and exit if the AR is all sign bits. ;It will set AROV and jump to NOP if it finds some data bits. OVTST1: AR_MQ, SKP AD NE ;get the sign bits from the MQ. =0 OVTEST: AR_SHIFT, I FETCH, J/OVTST2 ;the high word is all zeros - ok. GEN AR+1, SKP AD NE ;check to see if it is all ones. =0 AR_SHIFT, I FETCH, J/OVTST2 ;this is simply a negative number. SET AROV, I FETCH, J/NOP ;sorry, we found some data bits. OVTST2: AC0_AR, J/NOP ;finish the store.

.TOC "GFLT DATA CONVERSION INSTRUCTIONS" 1013: L-XBLT: J/LUUO 1014: L-GTPI: J/LUUO 1104: L-SFTE: J/LUUO 1105: L-GTDI: J/LUUO 1106: L-GTSI: J/LUUO 1107: L-GTDR: J/LUUO 1110: L-GTSR: J/LUUO 1111: L-DITE: J/LUUO 1112: L-SITE: J/LUUO 1113: L-EFSC: J/LUUO .IF/XADDR 3013: ARX_AC2, J/XBLT ; -20- XBLT .ENDIF/XADDR 3014: [AR]_FM[E1], J/L-GTSP ; -21- GSNGL 3104: [AR]_FM[E1], J/L-EDBL ; -22- GDBLE .IFNOT/GFTCNV ;[273] 3105: J/MUUO ; -23- DGFIX ;[273] 3106: J/MUUO ; -24- GFIX ;[273] 3107: J/MUUO ; -25- DGFIXR ;[273] 3110: J/MUUO ; -26- GFIXR ;[273] .IF/GFTCNV ;[273] 3105: [AR]_FM[E1], J/L-GTIN ; -23- DGFIX 3106: [AR]_FM[E1], J/L-GTIN ; -24- GFIX 3107: [AR]_FM[E1], J/L-GTIN ; -25- DGFIXR 3110: [AR]_FM[E1], J/L-GTIN ; -26- GFIXR .ENDIF/GFTCNV ;[273] 3111: [AR]_FM[E1], J/L-FLTR ; -27- DGFLTR 3112: [AR]_FM[E1], J/L-DFLT ; -30- GFLTR 3113: [AR]_FM[E1], J/L-DFSC ; -31- GFSC

L-GTSP: VMA_AR, LOAD AR ;-21- GSNGL EDPFP TO SPFP AR_MEM, MQ_0.S ;load high word into AR. GEN AR, SKP AD NE ;check for zeroes. =0 I FETCH, J/STORAC ;high word zero, store it. VMA_VMA+1 ;point to mem low word. =0 ARX_AR, SKP AR0, ;save high word in ARX. CALL [ISOEXP] ;get the excess-2000 exponent. CLR AR, BR/AR ;exp to BR. AR0-8_#, #/220 ;largest exponent allowed is 2200. GEN AR-BR-1, SKP AD0 ;range check exponent. =0 AR0-8_#, #/157, J/L-GTS1;do lower range check now.(actually too low) SET FLOV, I FETCH, J/NOP;tough L-GTS1: BR/AR, AR_BR ;swap values around for next subtract. GEN AR-BR, SKP AD0 ;do lower range check. =0 BR/AR, CLR AR, J/L-GTS6 ;passed. 10 bit path to do last checks. SET FXU, I FETCH, J/NOP ;too low. L-GTS6: AR0-8_#, #/160 ;subtract 1600 to get excess 200 exp. AR_BR, BR/AR ;swap around to do subtract. AR_AR-BR ;got it. AR_AR*8 ;move excess-200 exponent over. FE_AR0-8, AR_ARX, ;put some exponent in FE. High word to AR. LOAD ARX ;low word to ARX. ;This next test determines the relative size of the exponent. If the expo- ;nent is less than 401 then it is a positive exponent and all will be well. ;If the exponent is greater than 400 (actually 700), then the exponent is ;really negative but bit 0 of the FE is off. To correct the sign of the ;exponent and to prevent undeserved FXU later because of the incorrect sign ;bit, we must examine the value of the exponent so as to always get the ;correct sign during normalization. ARX_MEM, GEN FE-#, ;undeserved FXU happens when FE00 should be #/500, SKP SCAD0;set from previous subtract of 1600. =0 FE_FE+#, #/777, ;set FE00. Later add will clear it. ARX_ARX*2, ;low word * 2. J/L-GTS7 ;continue. FE_FE-1, ARX_ARX*2 ;adjust FE so later add gets right exp. =0 L-GTS7: SKP AR0, CALL [SGNEXT] ;sign extend high word. AR_AR*.25 LONG, ;prepare for normalization FE_FE+#, #/6, ;adjust exponent. NORM, J/SNORM ;finish up. L-EDBL: VMA_AR, LOAD AR ;-22- GDBLE SPFP to EXTENDED EXPONENT AR_MEM, CLR MQ SC_EXP, ARX_AR, CLR AR ;correct the expoent, save a copy in the ARX FM[E1]_AR ;no sticky bits here. EXP_SC ;put the "positive" exponent back IN THE AR. AR_AR*.5 ;must move exponent into AR4-11 AR_AR*.25 ; done. BR/AR, CLR AR ;exp to BR. AR0-8_#, #/160 ;put 1600 in the AR for exp conversion AR_AR+BR, FE_#, #/-3 ;convert exp, set initial exp correction FM[T2]_AR, AR_ARX ;save exp for ENORM, frac to AR EXP_SIGN.C, ARX_0.M ;get rid of exp, clear low word GEN AR, SC_#, #/3, NORM,;normalize an extended exponent number J/ENORM

.IF/GFTCNV ;[273] L-GTIN: VMA_AR, LOAD AR ;23-26. fetch high word. AR_MEM, MQ_0.S, ;word in AR, init MQ. VMA_VMA+1 ;prepare to fetch low word. GEN AR, SKP AD NE ;is high word all zeroes ? =0 CLR ARX, EXIT DBL ;high word zero, store zeroes. LOAD ARX, B DISP ;fetch low word, call appropriate routine. =000 ARX_MEM, J/L-G23 ;do GDP to DP integer, truncate. =010 ARX_MEM, J/L-G24 ;do GDP to SP integer, truncate. =100 ARX_MEM, J/L-G25 ;do GDP to DP integer, rounded. =110 ARX_MEM, J/L-G26 ;do GDP to SP integer, rounded. = ;terminate this dispatch block. ;DGFIX needs the sticky bit fix. =0010 L-G23: FE_#, #/70., ;-23- DGFIX GDP to double integer, truncate. CALL [ETXIX] ;do the conversion =0110 EXIT DBL ;store results. =0111 BR_AR LONG, AR_ARX, ;save high 2 words in BR!BRX, MSB of ARX/MQ, ;fraction to AR35. Rest of fraction to ARX. SC_#, #/35., ;get fraction all together. CALL [EF12A] =1111 GEN AR, SKP AD NE, ;any fraction bits on ? MQ_0.S ;[240]CLEAR MQ00 FOR ARX_2 MACRO. =0 AR_BR LONG, J/ST2AC ;no, leave answer alone. CLR AR, ARX_2 ;yes, add 1 to integer part. AR_AR+BR LONG, J/ST2AC ;store result. ;GFIX needs the sticky bit fix. =0010 L-G24: FE_#, #/35., ;-24- GFIX GDP to single integer, truncate. CALL [ETXIX] ;do the conversion =0110 L-GTS2: SKP AR NE, J/OVTEST ;test for sign bits in AR and store. =0111 BR_AR LONG, AR_ARX, ;save in BR!BRX. ARX/MQ, ;add one to integer part of negative number SC_#, #/35., ;if fraction is not zero. CALL [EF12A] =1111 GEN AR, SKP AD NE, ;is fraction zero ? MQ_0.S ;[240]CLEAR MQ00 FOR ARX_2 MACRO. =0 AR_BR LONG, SKP AD NE, ;yes, try to store the result. J/OVTEST CLR AR, ARX_2 ;no, add one to integer part. AR_AR+BR LONG, SKP AD NE,; do the add and test that the high J/OVTEST ;word is all sign bits. =011 L-G25: FE_#, #/70., ;-25- DGFIXR GDP to double integer, rounded. CALL [ETXIX] ;do the conversion =111 BR_AR LONG, CLR AR, ;save in BR!BRX, round by adding one half ARX_1, ;to result. Remember that the MSB of the SC_#, #/35. ;store routine expects this. AR_AR+BR LONG, AD FLAGS ;fraction is on ARX35. Do the rounding and ;=0 ; replace SKP CRY0 with AD FLAGS. Eliminates extra word. EXIT DBL ; store the double result. ; SET AROV, I FETCH, J/NOP;rounding caused an overflow - too bad! =011 L-G26: FE_#, #/35., ;-26- GFIXR GDP to single integer, rounded. CALL [ETXIX] ;do the conversion. =111 BR_AR LONG, CLR AR, ;save in CR!BRX, round by adding one half ARX_1, ;to result. MSB of the fraction is in ARX35. SC_#, #/35. ;store routine expects this. AR_AR+BR LONG, SKP AD NE,;do the rounding. J/OVTEST ;figure out what, if any, to store. .ENDIF/GFTCNV ;[273] L-FLTR: VMA_AR, LOAD AR, ;-27- DGFLTR DP INTEGER to EDPFP FE_#, #/137 ;inital fugde factor for exp AR_MEM, MQ_0.S ;get high word into the AR. =0* VMA_VMA+1, LOAD ARX, ;get the low word into the ARX, BR/AR, CALL [XFERW]; and save the high word in the BR. =1* ARX_ARX*2, CLR AR ;ignore the sign copy. FM[E1]_AR ;no sticky bits here. AR0-8_#, #/200 ;ENORM expects the exponent in T2. FM[T2]_AR, AR_BR, ;and save it in T2. ARX/AD, MQ_ARX ;sign to AR, high to ARX, low to MQ. AR_SIGN ; GEN AR, NORM, J/ENORM ;restore high word and normalize.

L-DFLT: VMA_AR, LOAD AR, ;-30- GFLTRSP INTEGER to EDPFP FE_#, #/4 ;initial fudge factor for exp. AR_MEM, CLR MQ ;get the single precision op. AR_SIGN, ARX_AR ;build a dummy high word of all sign. BR/AR, CLR AR ;save sign, prepare for exponent. FM[E1]_AR ;no sticky bits here. AR0-8_#, #/207 ;build an initial exp of 207 for ENORM FM[T2]_AR, AR_BR, ;save exp for ENORM, restore sign word. NORM, J/ENORM ;and normalize it. =0 L-DFSC: AR_AC0, BR/AR, SKP AD0, ;-31- GFSC EDPFP SCALE CALL [ISOEXP] ;get the exponent into the AR. BR/AR, AR_BR ;put exp in BR, scale factor to AR. AR_AR SWAP, GEN AC0, ;put scale in left half of AR. SKP AD NE ;is high word zero ? =0 AR+ARX+MQ_0.M, J/ST2AC ;yes, store zero as double result. AR_SIGN, ARX_AR, SC_#, ;no, move sign and scale factor together. #/34. AR_SHIFT, CLR FE ;sign now in AR00, scale in AR 9-19. EXP_SIGN ;scale sign is in AR00; extend it. SC_#, #/8. ;move scale factor into AR 1-11 and AR_SHIFT, ARX_AC1 ; put the sign to left of scale factor. AR_AR+BR, CLR MQ ;add exponent and scale factor. SH/AR, DISP/SH0-3 ;check for over and under flovs. =0011 L-FSC2: [AR]_[AR]*FM[EXPMSK], ;clear out non-exponent bits. AD/ANDCB, ;and AR00 in the over or under flow case. J/L-FSC3 ; and continue =0111 [AR]_[AR]*FM[EXPMSK], ;clear out non-exponent bits. AD/ANDCB, ; J/L-FSC3 ; and continue =1011 SET FLOV, J/L-FSC2 ;you lose =1111 SET FXU, J/L-FSC2 ;ditto L-FSC3: FM[T2]_AR, ARX_ARX*2 ;save new exponent fofr ENORM. =0 AR_AC0, SKP AD0, ;get the high word. SC_#, #/3, ;for ENORM. CALL [SGNEXT] ;and sign extend it for ENORM as well. GEN AR, NORM, J/ENORM ;put the result back together. .ENDIF/EXTEXP .ENDIF/MODEL.B