On 04 May 2010, at 12:51, Michael Van Canneyt wrote:

> The i386 version of the compiler is simply much more optimized as the 64-bit
> version (as are all FPC-generated binaries).

That was true pre-2.4.0, but as of 2.4.0 the assembler optimiser is no longer 
enabled by default on i386 (and it didn't make that big of a difference in 
previous versions either). There are still some more peephole optimisations for 
i386, but I don't think the i386 code that FPC generates is that much more 
optimised than that for x86_64 at this point (or even PowerPC, for that matter).

And as far as the speed of the compiler binary is concerned depending on 
whether it consists of i386 or x86_64 machine code (using -a -s so that the 
speed of the external assembler is not included):

i386->i386 compiler compiling itself:
user    0m8.180s
sys     0m0.694s

x86-64->i386 compiler compiling itself:
user    0m8.096s
sys     0m0.736s

So at least on Mac OS X there is no real speed difference between the two.


Jonas_______________________________________________
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