The readme file for the new version 1.26B of the IAR compiler talks about a new intrinsic function _SWAP_BYTES. <quote> New features A new intrinsic function _SWAP_BYTES has been implemented in the compiler. This function executes the SWPB instruction. unsigned short _SWAP_BYTES(unsigned short dst); </quote> I thought that I would try it out. Result = disappointment. The function prototype does not appear in my copy of IN430.H (presumably it should have been updated by the installation of the new version), and XLINK throws an error E46 (undefined external). Has anyone managed to use this function or have IAR messed up this release? Awaiting a response from IAR support. Ian _________________________________________________________________ Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?pageatures/featuredemail
New _SWAP_BYTES intrinsic function in IAR V1.26B
Started by ●November 22, 2002
Reply by ●November 22, 20022002-11-22
providing 'a' is 16bits unsigned normal compilers will do swap bytes for: (a<<8) | (a>>8) ~d --- In msp430@y..., "Ian Okey" <ian_okey@h...> wrote: > The readme file for the new version 1.26B of the IAR compiler talks about a > new intrinsic function _SWAP_BYTES. > > <quote> > New features > > A new intrinsic function _SWAP_BYTES has been implemented in the compiler. > This function executes the SWPB instruction. > > unsigned short _SWAP_BYTES(unsigned short dst); > > </quote> > > I thought that I would try it out. Result = disappointment. > > The function prototype does not appear in my copy of IN430.H (presumably it > should have been updated by the installation of the new version), and XLINK > throws an error E46 (undefined external). > > Has anyone managed to use this function or have IAR messed up this release? > > Awaiting a response from IAR support. > > Ian > > _________________________________________________________________ > Add photos to your messages with MSN 8. Get 2 months FREE*. > http://join.msn.com/?pageatures/featuredemail
Reply by ●November 23, 20022002-11-23
> providing 'a' is 16bits unsigned
> normal compilers will do swap bytes for:
> (a<<8) | (a>>8)
I don't think that's the point here ...........
Ian's talking about the presence/absence of an intrinsic
Reply by ●November 23, 20022002-11-23
On Sat, Nov 23, 2002 at 02:36:45PM +1100, Kris De Vos wrote: > > providing 'a' is 16bits unsigned > > normal compilers will do swap bytes for: > > (a<<8) | (a>>8) > > I don't think that's the point here ........... > Ian's talking about the presence/absence of an intrinsic I think you *missed* the point - given the code in question, the compiler should produce a swpb instruction, so there's no need for an "intrinsic". -- Clyde Stubbs | HI-TECH Software Email: clyde@clyd... | Phone Fax WWW: http://www.htsoft.com/ | USA: (408) 490 2885 (408) 490 2885 PGP: finger clyde@clyd... | AUS: +61 7 3552 7777 +61 7 3552 7778 --- HI-TECH C: compiling the real world.
Reply by ●November 23, 20022002-11-23
At 02:30 PM 11/22/2002 +0000, diwilru wrote: >providing 'a' is 16bits unsigned >normal compilers will do swap bytes for: >(a<<8) | (a>>8) > >~d hey, that's pretty neat. I will add it to the compiler. // richard <http://www.imagecraft.com> <http://www.dragonsgate.net/mailman/listinfo> On-line orders, support, and listservers available on web site. [ For technical support on ImageCraft products, please include all previous replies in your msgs. ]
Reply by ●November 23, 20022002-11-23
At 08:26 PM 11/22/2002 -0800, Richard wrote: >At 02:30 PM 11/22/2002 +0000, diwilru wrote: > >providing 'a' is 16bits unsigned > >normal compilers will do swap bytes for: > >(a<<8) | (a>>8) > > > >~d > >hey, that's pretty neat. I will add it to the compiler. Hey pretty good eh? FILE: swapb.c (0001) unsigned x; (0002) main() (0003) { (0004) unsigned a = 0xAAFF; _main: b --> R5 a --> R4 306C 4034 AAFF mov #0xAAFF,R4 (0005) (0006) unsigned b = (a << 8) | (a >> 8); 3070 4405 mov R4,R5 3072 1085 swpB R5 (0007) (0008) a = (a << 8) | (a >> 8); 3074 1084 swpB R4 (0009) (0010) x = (x << 8) | (x >> 8); 3076 1090 D188 swpB 0200 (0011) } // richard <http://www.imagecraft.com> <http://www.dragonsgate.net/mailman/listinfo> On-line orders, support, and listservers available on web site. [ For technical support on ImageCraft products, please include all previous replies in your msgs. ]
Reply by ●November 23, 20022002-11-23
Hey Clyde, didn't know you were on this forum, long time no talk ... (Are you looking into an MSP430 tool as well ?) Anyway, looks like we're gonna go get into useless trivia here : Ian posted his dissapointment with the fact that IAR's EW430 - V1.26B ( despite the claim it's there ) intrinsics header file <in430.h> didn't have the SWAP byte intrinsic included...... (I haven't purchased another SUA, so I'm still using V1.26A, well actually - V1.24A most of the time), so I can't help..... Whether "other" compilers (even EW430 itself) generate a byte swap with the C code supplied (which is bleeding obvious) is *completely irrelevant*. I don't think I *missed* the point at all, I think the whole thread should be visited first......... There are many intrinsics that are not necessary, but they make C programming easier and more accessible for newcomers...... I think Ian Okey's point is a salient one, and further seeks if other people found the intrinsic missing as well. THAT WAS IAN'S QUESTION...... BTW : IAR will generate a swap even when merely stating : a = (unsigned char) (a>>8); Furthermore, it depends on where the UINT "a" is located. If it's on the stack frame as an auto var, and not in a register - then the C code will not work in generating a mere "swap" instruction ......... B rgds Kris ----- Original Message ----- From: Clyde Stubbs To: msp430@msp4... Sent: Saturday, November 23, 2002 3:12 PM Subject: Re: [msp430] Re: New _SWAP_BYTES intrinsic function in IAR V1.26B On Sat, Nov 23, 2002 at 02:36:45PM +1100, Kris De Vos wrote: > > providing 'a' is 16bits unsigned > > normal compilers will do swap bytes for: > > (a<<8) | (a>>8) > > I don't think that's the point here ........... > Ian's talking about the presence/absence of an intrinsic I think you *missed* the point - given the code in question, the compiler should produce a swpb instruction, so there's no need for an "intrinsic". -- Clyde Stubbs | HI-TECH Software Email: clyde@clyd... | Phone Fax WWW: http://www.htsoft.com/ | USA: (408) 490 2885 (408) 490 2885 PGP: finger clyde@clyd... | AUS: +61 7 3552 7777 +61 7 3552 7778 --- HI-TECH C: compiling the real world. .
Reply by ●November 23, 20022002-11-23
Richard, just look at the gcc port sources. It has already lots of features implemented (especially interesting peepholes). If you've got questions - ask :) ~d --- In msp430@y..., "Richard F. Man" <richard@i...> wrote: > At 08:26 PM 11/22/2002 -0800, Richard wrote: > >At 02:30 PM 11/22/2002 +0000, diwilru wrote: > > >providing 'a' is 16bits unsigned > > >normal compilers will do swap bytes for: > > >(a<<8) | (a>>8) > > > > > >~d > > > >hey, that's pretty neat. I will add it to the compiler. > > Hey pretty good eh? > > > FILE: swapb.c > (0001) unsigned x; > (0002) main() > (0003) { > (0004) unsigned a = 0xAAFF; > _main: > b --> R5 > a --> R4 > 306C 4034 AAFF mov #0xAAFF,R4 > (0005) > (0006) unsigned b = (a << 8) | (a >> 8); > 3070 4405 mov R4,R5 > 3072 1085 swpB R5 > (0007) > (0008) a = (a << 8) | (a >> 8); > 3074 1084 swpB R4 > (0009) > (0010) x = (x << 8) | (x >> 8); > 3076 1090 D188 swpB 0200 > (0011) } > > > > // richard <http://www.imagecraft.com> > <http://www.dragonsgate.net/mailman/listinfo> > On-line orders, support, and listservers available on web site. > [ For technical support on ImageCraft products, please include all previous > replies in your msgs. ]
Reply by ●November 23, 20022002-11-23
At 09:13 AM 11/23/2002 +0000, you wrote: >Richard, >just look at the gcc port sources. It has already lots of features >implemented (especially interesting peepholes). >If you've got questions - ask :) > >~d Sure, why don't you just email me the .md file :-) // richard <http://www.imagecraft.com> <http://www.dragonsgate.net/mailman/listinfo> On-line orders, support, and listservers available on web site. [ For technical support on ImageCraft products, please include all previous replies in your msgs. ]
Reply by ●November 23, 20022002-11-23
> > BTW : IAR will generate a swap even when merely stating : > a = (unsigned char) (a>>8); > Furthermore, it depends on where the UINT "a" is located. > If it's on the stack frame as an auto var, and not in a register - then the C code will not work in generating a mere > "swap" instruction ......... Are swbp @Rn or swpb &A or swpb X(Rn) incortect? What's the problem with auto vars in a such 'rotate' instruction? Richard, most recent (and actually all of them) .md file is available on the web in mspgcc.sf.net ~d > ----- Original Message ----- > From: Clyde Stubbs > To: msp430@y... > Sent: Saturday, November 23, 2002 3:12 PM > Subject: Re: [msp430] Re: New _SWAP_BYTES intrinsic function in IAR V1.26B > > > On Sat, Nov 23, 2002 at 02:36:45PM +1100, Kris De Vos wrote: > > > providing 'a' is 16bits unsigned > > > normal compilers will do swap bytes for: > > > (a<<8) | (a>>8) > > > > I don't think that's the point here ........... > > Ian's talking about the presence/absence of an intrinsic > > I think you *missed* the point - given the code in question, the compiler > should produce a swpb instruction, so there's no need for an "intrinsic". > > -- > Clyde Stubbs | HI-TECH Software > Email: clyde@h... | Phone Fax > WWW: http://www.htsoft.com/ | USA: (408) 490 2885 (408) 490 2885 > PGP: finger clyde@h... | AUS: +61 7 3552 7777 +61 7 3552 7778 > --- > HI-TECH C: compiling the real world. > > To unsubscribe from the msp430 group, send an email to: > msp430-unsubscribe@e... > > > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > > > >
