d8d2e05eb2
find is the biggest chunk of logic of the boot code. The 8086 version is significantly terser than the z80 one. REP/CMPS helps...
17 lines
733 B
Plaintext
17 lines
733 B
Plaintext
L4 BSET PC 3 - ORG @ 4 + ! ( find )
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( find word the same name as str in SI starting from tip in
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DI. Returns wordref in BX. Z if found, NZ if not. )
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CH CH XORrr, CL [SI] MOVr[], ( CX -> strlen )
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SI INCx, ( first char ) AX AX XORxx, ( initial prev )
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BEGIN, ( loop )
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DI AX SUBxx, ( jump to prev wordref )
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DI DECx, AL [DI] MOVr[], ( strlen )
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CL AL CMPrr, IFZ, ( same len )
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SI PUSHx, DI PUSHx, CX PUSHx, ( --> lvl 3 )
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2 ADDALi, ( prev ) AH AH XORrr, DI AX SUBxx,
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REPZ, CMPSB,
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CX POPx, DI POPx, SI POPx, ( <-- lvl 3 )
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IFZ, DI INCx, AL AL XORrr, ( Z ) RETn, THEN,
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THEN,
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( cont. )
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