Print Page - Silly question, inc(ix+3) in sdasz80 (SDCC assembler)??

Title: Silly question, inc(ix+3) in sdasz80 (SDCC assembler)??
Post by: johnlobo on 18:10, 22 February 22

Hi all,
One silly question for the experts in CPCTelera assembler.

In sdasz80, the assembler of SDCC, the syntax for using ix and iy registers is something like...

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ld a, 3(ix)
and can be also used with constants

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ld a, e_life(ix)

...but does anybody know what's the syntax for the increment of the referenced value ??

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inc (e_life(ix)) produces a "missing or improper operators, terminators, or delimiters error"

But, in plain assembler something like this...

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inc (ix +3)
proceduces the code 34 ff 03.. so it's a valid opcode, and I guess that must be implemented somehow in sdasz80, even though I've been trying different sytax alternatives with no success.

Any help??

Thanks in advance.

Title: Re: Silly question, inc(ix+3) in sdasz80 (SDCC assembler)??
Post by: reidrac on 19:32, 22 February 22

I just tried "inc 3 (ix)" and it works, and "inc CONSTANT (ix)" works too. This is SDCC 4.0.

EDIT: of course, I encourage you to avoid using ix and iy. That's slow! :laugh:

Title: Re: Silly question, inc(ix+3) in sdasz80 (SDCC assembler)??
Post by: johnlobo on 00:20, 23 February 22

Great!! it works.
Thank you very much.

Must be the only combination I didn't try myself... :D
In any case, you're right, I'll try not tu abuse of index registries, even though in my current game speed is not a key factor.
Regards.

Quote from: reidrac on 19:32, 22 February 22I just tried "inc 3 (ix)" and it works, and "inc CONSTANT (ix)" works too. This is SDCC 4.0.

EDIT: of course, I encourage you to avoid using ix and iy. That's slow! :laugh:

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General Category => Programming => Topic started by: johnlobo on 18:10, 22 February 22