mirror of https://github.com/hsoft/collapseos.git
45 lines
1.1 KiB
NASM
45 lines
1.1 KiB
NASM
; Parse string in (HL) and return its numerical value whether its a number
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; literal or a symbol. Returns value in IX.
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; Sets Z if number or symbol is valid, unset otherwise.
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parseNumberOrSymbol:
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call parseLiteral
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ret z
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; Not a number.
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; Is str a single char? If yes, maybe it's a special symbol.
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call strIs1L
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jr nz, .symbol ; nope
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ld a, (hl)
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cp '$'
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jr z, .returnPC
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cp '@'
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jr nz, .symbol
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; last val
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ld ix, (DIREC_LASTVAL)
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ret
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.symbol:
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push de ; --> lvl 1
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call symFindVal ; --> DE
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jr nz, .notfound
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; value in DE. We need it in IX
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push de \ pop ix
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pop de ; <-- lvl 1
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cp a ; ensure Z
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ret
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.notfound:
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pop de ; <-- lvl 1
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; If not found, check if we're in first pass. If we are, it doesn't
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; matter that we didn't find our symbol. Return success anyhow.
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; Otherwise return error. Z is already unset, so in fact, this is the
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; same as jumping to zasmIsFirstPass
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; however, before we do, load IX with zero. Returning dummy non-zero
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; values can have weird consequence (such as false overflow errors).
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ld ix, 0
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jp zasmIsFirstPass
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.returnPC:
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push hl
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call zasmGetPC
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push hl \ pop ix
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pop hl
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ret
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