Am 02.01.2015 um 21:34 schrieb Jonas Maebe: > On 02/01/15 21:16, Florian Klämpfl wrote: >> Am 02.01.2015 um 19:31 schrieb Juha Manninen: >>> Does it make sense to use PtrInt instead of Integer for optimization or >>> code size reasons? >> >> Hard to say, but I wouldn't expect a benefit because bigger data types means >> also more cache pollution. >> >>> In other words, does the compiler generate faster or smaller code in 64-bit >>> CPUs for the native >>> integer size? >> >> Normally the code is a little bit smaller (less sign extensions), but the >> data footprint is bigger. >> >>> Does it depend on architecture? >> >> The comments above are probably valid for all 64 bit CPUs except alpha which >> is not supported by fpc. > > And except for AArch64, where 32 bit will, in principle, also be more > efficient than 64 bit in all cases. It can even use the lower 8/16/32 > bit of a register as index in a memory references and sign/zero-extend + > optionally multiply it with the access size.
But integer operations are done always on 64 bit in FPC? _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal