* Re: [Sim] Patch to sim/common/cgen-ops.h [not found] <200012040402.eB442Sk23037@scooby.cygnus.com> @ 2000-12-03 20:12 ` Andrew Cagney 2000-12-03 21:09 ` Doug Evans 2000-12-04 4:55 ` Frank Ch. Eigler 0 siblings, 2 replies; 6+ messages in thread From: Andrew Cagney @ 2000-12-03 20:12 UTC (permalink / raw) To: Ben Elliston; +Cc: gdb-patches, cgen Oh, what the heck. Why is CGEN follow the GCC convention of SI, UI, BI, ZI, NFI, rather than the sim-common convention of signed8, unsigned64, ... Andrew ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Sim] Patch to sim/common/cgen-ops.h 2000-12-03 20:12 ` [Sim] Patch to sim/common/cgen-ops.h Andrew Cagney @ 2000-12-03 21:09 ` Doug Evans 2000-12-03 22:27 ` Ben Elliston 2000-12-04 4:55 ` Frank Ch. Eigler 1 sibling, 1 reply; 6+ messages in thread From: Doug Evans @ 2000-12-03 21:09 UTC (permalink / raw) To: Andrew Cagney; +Cc: Ben Elliston, gdb-patches, cgen Andrew Cagney writes: > Oh, what the heck. > > Why is CGEN follow the GCC convention of SI, UI, BI, ZI, NFI, rather > than the sim-common convention of signed8, unsigned64, ... 'cus cgen rtl is based on gcc rtl and I like having the types be the same in the emitted code as in the rtl. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Sim] Patch to sim/common/cgen-ops.h 2000-12-03 21:09 ` Doug Evans @ 2000-12-03 22:27 ` Ben Elliston 2000-12-04 10:53 ` Doug Evans 0 siblings, 1 reply; 6+ messages in thread From: Ben Elliston @ 2000-12-03 22:27 UTC (permalink / raw) To: Doug Evans; +Cc: Andrew Cagney, gdb-patches, cgen > Why is CGEN follow the GCC convention of SI, UI, BI, ZI, NFI, rather > than the sim-common convention of signed8, unsigned64, ... 'cus cgen rtl is based on gcc rtl and I like having the types be the same in the emitted code as in the rtl. I think Andrew was asking why the rtl uses these names. Using other names for the modes would not preclude the use of an rtl, it just wouldn't look like GCC's. Is that a bad thing, given that it would allow the programmer to be more explicit about data representation on the target side? Ben ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Sim] Patch to sim/common/cgen-ops.h 2000-12-03 22:27 ` Ben Elliston @ 2000-12-04 10:53 ` Doug Evans 2000-12-04 14:31 ` Andrew Cagney 0 siblings, 1 reply; 6+ messages in thread From: Doug Evans @ 2000-12-04 10:53 UTC (permalink / raw) To: Ben Elliston; +Cc: Andrew Cagney, gdb-patches, cgen Ben Elliston writes: > > Why is CGEN follow the GCC convention of SI, UI, BI, ZI, NFI, rather > > than the sim-common convention of signed8, unsigned64, ... > > 'cus cgen rtl is based on gcc rtl and I like having the types be the > same in the emitted code as in the rtl. > > I think Andrew was asking why the rtl uses these names. Using other names > for the modes would not preclude the use of an rtl, it just wouldn't look > like GCC's. Is that a bad thing, given that it would allow the programmer > to be more explicit about data representation on the target side? Andrew may have just been refering to the name choice used in the generated code. Either way, this is just a naming choice issue. I like the current scheme. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Sim] Patch to sim/common/cgen-ops.h 2000-12-04 10:53 ` Doug Evans @ 2000-12-04 14:31 ` Andrew Cagney 0 siblings, 0 replies; 6+ messages in thread From: Andrew Cagney @ 2000-12-04 14:31 UTC (permalink / raw) To: Doug Evans; +Cc: Ben Elliston, gdb-patches, cgen Doug Evans wrote: > Andrew may have just been refering to the name choice used in the > generated code. Either way, this is just a naming choice issue. > I like the current scheme. Kind of. My understanding is that there are three type systems kicking around: host target abstract host: This is the compiler on which the system is being run. It has types such as int, long, unsigned, ... Their semantics are host platform dependant target: This is the type system of the target. At one level there are the types for the target compiler (eg int which could be 16 bits). At another level there are the concrete semantics of specific operations. abstract/portable: For sim/common (which took things from PPC). This was a type system that was platform independant. The semantics of something like: unsigned64 = (signed32) val; were well defined. It is more fully: unsigned64 = (unsigned64)(signed64)(signed32) val; The two important things were that: o The semantics were not tied to either the host or the target. Instead they are defined abstractly. o It used a very standard convention. C9x adopted int8 etc. Some have used __u8 et.al. Programmers are going to be instantly familar with such a convention. They are going to simply be bamboozled by a more obscure SI, DI, et.al. convention. sim/common used signed8 et.al. I've more recently seen a suggestion for S8, U16, et.al. I think there are strong technical arguments for avoiding the SI, DI convention and instead using an abstract type system that more clearly defines its own semantics. enjoy, Andrew ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Sim] Patch to sim/common/cgen-ops.h 2000-12-03 20:12 ` [Sim] Patch to sim/common/cgen-ops.h Andrew Cagney 2000-12-03 21:09 ` Doug Evans @ 2000-12-04 4:55 ` Frank Ch. Eigler 1 sibling, 0 replies; 6+ messages in thread From: Frank Ch. Eigler @ 2000-12-04 4:55 UTC (permalink / raw) To: Andrew Cagney; +Cc: Ben Elliston, gdb-patches, cgen Hi - On Mon, Dec 04, 2000 at 03:02:54PM +1100, Andrew Cagney wrote: : [...] : Why is CGEN follow the GCC convention of SI, UI, BI, ZI, NFI, rather : than the sim-common convention of signed8, unsigned64, ... CGEN does more than simulators (assembler/disassembler) and more simulators than sim/common. - FChE -- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE6K5RKVZbdDOm/ZT0RAjZSAJ91/N/P2BBJtWGX+g3UEn7C/XIJ/wCeLlb/ dbI2Cnl4OkwOLABL9oWdd0E= =nyVA -----END PGP SIGNATURE----- ^ permalink raw reply [flat|nested] 6+ messages in thread
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[not found] <200012040402.eB442Sk23037@scooby.cygnus.com>
2000-12-03 20:12 ` [Sim] Patch to sim/common/cgen-ops.h Andrew Cagney
2000-12-03 21:09 ` Doug Evans
2000-12-03 22:27 ` Ben Elliston
2000-12-04 10:53 ` Doug Evans
2000-12-04 14:31 ` Andrew Cagney
2000-12-04 4:55 ` Frank Ch. Eigler
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