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Amir

Member

From: UAE

Registered: 2010-08-17

Posts: 36

Delphi x64 inline assembler...

The place to exchange ideas and experiences on Delphi x64 assembly programming.

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Amir

Arioch

Member

Registered: 2011-11-17

Posts: 28

Re: Delphi x64 inline assembler...

In XE2 assembler is screwed, sometimes it just inverts the logic in your code

http://qc.embarcadero.com/wc/qcmain.aspx?d=105876

and still not-fixed http://qc.embarcadero.com/wc/qcmain.aspx?d=105877

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,225

Website

Re: Delphi x64 inline assembler...

'loop' is in fact slower than dec ecx + jnz @... so it is not a big issue.

There are also some issues / missing opcodes in x64 asm.
See http://blog.synopse.info/post/2013/03/1 … -for-Win64

Arioch

Member

Registered: 2011-11-17

Posts: 28

Re: Delphi x64 inline assembler...

@ab

it maybe would not be a big issue if it changes loop for dec/jnz - apart from i COULD be dependent on the certain opcodes and their lengths.

However delphi exchanged look for an opposite instractions seq: dec cx / JZ ... ensuring loop would exit immediately

PS: after rereading my own report. Actually not even dec/jz, but just a jz without dec

Last edited by Arioch (2014-02-07 09:24:26)