[fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
Having recently asked about and learned that it is mainly a hint about performance. I have now another question about this hint: project1.lpr(6,9) Hint: Mixing signed expressions and longwords gives a 64bit result Actually not so much about the hint, as about the fact that in the below examp

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread ik
On Mon, Jan 14, 2013 at 3:11 PM, Martin wrote: > Having recently asked about and learned that it is mainly a hint about > performance. I have now another question about this hint: > project1.lpr(6,9) Hint: Mixing signed expressions and longwords gives a > 64bit result > > Actually not so much ab

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
On 14/01/2013 13:54, ik wrote: On Mon, Jan 14, 2013 at 3:11 PM, Martin wrote: Actually not so much about the hint, as about the fact that in the below example fpc extends the operands to 64 bits. program Project1; var x: cardinal; i, j: integer; begin i:= x or j end. i is an "integer

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Jonas Maebe
On 14 Jan 2013, at 14:11, Martin wrote: Having recently asked about and learned that it is mainly a hint about performance. I have now another question about this hint: project1.lpr(6,9) Hint: Mixing signed expressions and longwords gives a 64bit result Actually not so much about the hint

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Jonas Maebe
On 14 Jan 2013, at 14:54, ik wrote: On Mon, Jan 14, 2013 at 3:11 PM, Martin wrote: Having recently asked about and learned that it is mainly a hint about performance. I have now another question about this hint: project1.lpr(6,9) Hint: Mixing signed expressions and longwords gives a 64b

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
On 14/01/2013 14:10, Jonas Maebe wrote: That said, the compiler contains an optimization pass that tries to remove 64 bit widenings on 32 bit platforms in case it turns out they were not necessary. It will also catch the above example and the generated code will only contain a 32 bit operations

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Hans-Peter Diettrich
Martin schrieb: On 14/01/2013 13:54, ik wrote: On Mon, Jan 14, 2013 at 3:11 PM, Martin wrote: Actually not so much about the hint, as about the fact that in the below example fpc extends the operands to 64 bits. program Project1; var x: cardinal; i, j: integer; begin i:= x or j end.

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
On 14/01/2013 15:27, Hans-Peter Diettrich wrote: Martin schrieb: On 14/01/2013 13:54, ik wrote: On Mon, Jan 14, 2013 at 3:11 PM, Martin wrote: Actually not so much about the hint, as about the fact that in the below example fpc extends the operands to 64 bits. program Project1; var x: ca

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Jonas Maebe
On 14 Jan 2013, at 16:44, Martin wrote: This is casting a "set of bits" (neither signed, nor unsigned - a set is not a number at all) into a number. This only needs to have a definition, if it should cast to signed or unsigned type. It has to be signed, because otherwise any negative numbe

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
On 14/01/2013 15:52, Jonas Maebe wrote: On 14 Jan 2013, at 16:44, Martin wrote: This is casting a "set of bits" (neither signed, nor unsigned - a set is not a number at all) into a number. This only needs to have a definition, if it should cast to signed or unsigned type. It has to be signe

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Martin
Just to menion: I am NOT trying to get anything changed. It works fine for me as it is. I would however like to widen/correct my understanding of the matter On 14/01/2013 16:03, Martin wrote: not sure if I follow. If "or" performs on a "set of bits" (rather than a number), and a set (not bei

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Marco van de Voort
In our previous episode, Martin said: > not sure if I follow. If "or" performs on a "set of bits" (rather than a > number), and a set (not being a number) is neither signed or unsigned, > then before the "OR" both operands (independent of being signed or not) > will be cast to a set. The result

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Jonas Maebe
On 14 Jan 2013, at 17:03, Martin wrote: > On 14/01/2013 15:52, Jonas Maebe wrote: >> >> On 14 Jan 2013, at 16:44, Martin wrote: >> >>> This is casting a "set of bits" (neither signed, nor unsigned - a set is >>> not a number at all) into a number. This only needs to have a definition, >>> if

Re: [fpc-devel] Do bitwise operation (1 or 2) acre about the sign ? (Giving sign related hints on compilation)

2013-01-14 Thread Hans-Peter Diettrich
Martin schrieb: During above calculation ("or") a sign extension is required because the result *must* have a definite sign. Else a following comparison of e.g. (x or j)>0 could not determine a result. This is casting a "set of bits" (neither signed, nor unsigned - a set is not a number at al

Re: [fpc-devel] "embedded" again

2013-01-14 Thread Paul Breneman
Michael Schnell wrote: On 01/11/2013 12:37 PM, Michael Schnell wrote: I don't suppose I can run an X11 stub (such as NoMachine NX or whatever the Xorg stub is called) plus a widget set (such as QT) on the QNAP NA device. later I found this: http://www.tiaowiki.com/w/Install_NX_Server_on_Raspb