Florian Klaempfl a écrit : > > Marcel Martin wrote: > > > Florian Klaempfl a écrit : > > > >>Thomas Schatzl wrote: > >> > >>>In this case > >>> > >>> procedure nx_fill(P: PLongword; Count: Longint; Value: Longword); > >>> assembler; > >>> asm > >>> pushl %edi > >>> movl P,%edi // edi <- P > >>> movl Value,%eax // eax <- Value > >>> movl Count,%ecx // ecx <- Count > >>> rep > >>> stosl > >>> popl %edi > >>> end; > >>> > >>>works both as embedded and non-embedded assembler procedure because the > >>>order of assignments is ok in both cases. > >>> > >>>Btw, there's already a method in the system unit which does the same > >>>thing as your routine: filldword()... > >> > >>... and with better instruction selection ;) > > > > > > 1) This little routine was sent to point out a problem. > > > > 2) Better than what? Where do you see an "instruction selection" > > Push instead of mov. mov is faster on modern machines because it causes > less instruction dependencies.
1) That's what you call an 'instruction selection'? Such an answer is what I call bad faith. You were talking about checking the possible negativity of 'Count'. 2) Not with Delphi 5.01. With such a procedure, Delphi 5.01 doesn't generate the instructions "push ebp, etc. ". By using a local, you constraint it to do that. In short, if you want to use 2 mov's instead of push/pop by creating a local, you will have 2 mov's AND a push/pop. Now I agree, this is no more true with FPC 1.9.4 since it seems to generate the sequence "push ebp ..." as soon as there is a parameter (even if there is no local and if this parameter is sent through a register). But you know what? My library was written with (and for) Delphi 5.01 and, I am sorry, but adapting 30,000 lines of code for a compiler I don't know well cannot be done in two weeks. At least, _I_ cannot. 3) Next time I will have a problem with FPC, I will think twice before talking about it on this list. -- mm http://www.ellipsa.net/ _______________________________________________ fpc-pascal maillist - [EMAIL PROTECTED] http://lists.freepascal.org/mailman/listinfo/fpc-pascal
