collapseos/blk/286

lblnext BSET PC ORG @ 0x1b + ! ( next )
( This routine is jumped to at the end of every word. In it,
  we jump to current IP, but we also take care of increasing
  it by 2 before jumping. )
	( Before we continue: are we overflowing? )
    IX PUSH, EX(SP)HL, ( do EX to count the IX push in SP )
    SP SUBHLd, HL POP,
    IFNC, ( SP <= IX? overflow )
        SP PS_ADDR LDdn, IX RS_ADDR LDdn,
        DE BIN( @ 0x13 ( oflw ) + LDdd(n),
        JR, L3 FWR ( execute, B287 )
    THEN,
    LDA(BC), E A LDrr, BC INCd,
    LDA(BC), D A LDrr, BC INCd,
    ( continue to execute )
z80: remove layer of indirection in most "next" calls The only calls still using the stable ABI indirection are those made before the next routine is created. 2020-06-18 21:24:47 +10:00			`lblnext BSET PC ORG @ 0x1b + ! ( next )`
Copy boot.z80 to blkfs 2020-04-23 11:19:12 +10:00			`( This routine is jumped to at the end of every word. In it,`
			`we jump to current IP, but we also take care of increasing`
			`it by 2 before jumping. )`
z80: implement stack overflow error condition Also, remove underflow checks from next: it's taxing and useless because underflow check already takes place in each relevant native word. 2020-08-08 22:08:05 +10:00			`( Before we continue: are we overflowing? )`
			`IX PUSH, EX(SP)HL, ( do EX to count the IX push in SP )`
			`SP SUBHLd, HL POP,`
			`IFNC, ( SP <= IX? overflow )`
			`SP PS_ADDR LDdn, IX RS_ADDR LDdn,`
			`DE BIN( @ 0x13 ( oflw ) + LDdd(n),`
			`JR, L3 FWR ( execute, B287 )`
			`THEN,`
z80: Use BC as IP register instead of IY 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. 2020-07-07 13:31:00 +10:00			`LDA(BC), E A LDrr, BC INCd,`
			`LDA(BC), D A LDrr, BC INCd,`
Copy boot.z80 to blkfs 2020-04-23 11:19:12 +10:00			`( continue to execute )`