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e4a4a9800d
It's a bit more inconvenient in terms of register protection (BC is much more generally useful than IY), but it makes tight spots such as next and execute much faster, so I think it's worth it.
16 lines
542 B
Plaintext
16 lines
542 B
Plaintext
lblnext BSET PC ORG @ 0x1b + ! ( next )
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( This routine is jumped to at the end of every word. In it,
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we jump to current IP, but we also take care of increasing
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it by 2 before jumping. )
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( Before we continue: are stacks within bounds? )
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( PS ) HL PS_ADDR LDdn,
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SP SUBHLd,
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JRC, lblofl BWR ( abortUnderflow-B285 )
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( RS ) IX PUSH, HL POP,
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DE RS_ADDR LDdn,
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DE SUBHLd,
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JRC, lblofl BWR ( IX < RS_ADDR? abortUnderflow-B285 )
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LDA(BC), E A LDrr, BC INCd,
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LDA(BC), D A LDrr, BC INCd,
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( continue to execute )
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