C is a crappy

Article: MAQSIP-RT: An HPC Benchmark
By: Konrad Schwarz (no.spam.delete@this.no.spam), July 7, 2010 8:34 am
Room: Moderated Discussions
Ian Ollmann (iano@apple.com) on 7/6/10 wrote:
---------------------------
>1) Weak support for threading. The timing of operations is at times over-described or under-described.

This gives ISA designers the freedom to try out various relaxed memory models.

>2) No SIMD vector support / failure to standardize types early on -- how big is
>an int anyway? A double? What is the bit pattern for these things? (I group these
>together because many algorithms for vectors require fixed data representations.)

# include

# if INT_MAX >= 1 << (CHAR_BIT << 1)
# error An int is more than 2 bytes
/* and so on */
# endif

The point of C is portability, e.g. to both 2s complement and sign-magnitude machines -- never mind they no longer exist. That's why these things were not specified.

>3) Most of all -- The language is conversion-happy. Following basic hardware models
>of 50 years ago, it tries to convert everything to a core hardware type, do the
>work, and convert back.

Well, all my RISC machines work exactly this way, and I'm sure the x86 people would rather not have to deal with AH, AL, AX, EAX and RAX etc.

All the conversions are a problem, because they make it
>difficult to precisely describe an algorithm -- what you see is not what you get.
>E.g. short << 16, forces a conversion to int (of what size?) before the shift
>occurs, so if you right shift again later, those bits might be there or might not.

Can be solved with . Although P.J. Plaugher is to blame for C89's stupid move away from K+R C's rule of preserving unsignedness.
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TopicPosted ByDate
New article online: MAQSIP RTDavid Kanter2010/06/21 11:57 AM
  Why no GCC?Rohit2010/06/22 09:25 PM
    Why no GCC?David Kanter2010/06/23 12:45 AM
      sun 's cc better than GCC?Rohit2010/06/23 05:04 AM
        sun 's cc better than GCC?anon2010/06/23 07:49 AM
          Where is the GCC optimization effort directed?Mark Roulo2010/06/23 10:42 AM
            GCC is very ugly bad everywhere in 64 bitsVincent Diepeveen2010/06/23 02:49 PM
              even for 64-bit arch?anon2010/06/23 02:59 PM
              GCC is very ugly bad everywhere in 64 bitsajensen2010/06/23 11:03 PM
                GCC is very ugly bad everywhere in 64 bitsGabriele Svelto2010/06/24 02:33 AM
                  GCC is very ugly bad everywhere in 64 bitsajensen2010/06/24 05:32 AM
                    GCC is very ugly bad everywhere in 64 bitsGabriele Svelto2010/06/24 07:18 AM
                      GCC is very ugly bad everywhere in 64 bitsajensen2010/06/24 09:50 AM
                        Why GCC is big and complicated (my guess)Mark Roulo2010/06/24 12:17 PM
                          Why GCC is big and complicated (my guess)Gabriele Svelto2010/06/28 04:00 AM
                GCC is very ugly bad everywhere in 64 bitsBernd Schmidt2010/06/24 05:46 AM
                  GCC is very ugly bad everywhere in 64 bitsajensen2010/06/24 09:43 AM
                  GCC is very ugly bad everywhere in 64 bitsVincent Diepeveen2010/06/26 02:12 PM
                GCC is very ugly bad everywhere in 64 bitsRob Thorpe2010/06/24 07:47 AM
                  GCC is very ugly bad everywhere in 64 bitsAnon2010/06/24 05:23 PM
            Where is the GCC optimization effort directed?Gabriele Svelto2010/06/23 10:45 PM
              Where is the GCC optimization effort directed??2010/06/24 01:48 AM
                Where is the GCC optimization effort directed?Gabriele Svelto2010/06/24 02:29 AM
                  Where is the GCC optimization effort directed??2010/06/24 03:13 AM
                    Where is the GCC optimization effort directed?Andi Kleen2010/06/24 03:15 AM
                      Where is the GCC optimization effort directed??2010/06/24 04:08 AM
                    Where is the GCC optimization effort directed?Gabriele Svelto2010/06/24 03:54 AM
                      Where is the GCC optimization effort directed??2010/06/24 04:15 AM
                        Where is the GCC optimization effort directed?Gabriele Svelto2010/06/24 07:22 AM
                Where is the GCC optimization effort directed?Rohit2010/06/24 03:04 AM
                  Placebo effect?2010/06/24 06:37 AM
                    Placebo effectRohit2010/06/24 08:45 AM
                    Placebo effectVincent Diepeveen2010/06/26 02:50 PM
                      Compile timeMark Roulo2010/06/26 05:28 PM
                        Compile timeRichard Cownie2010/06/27 04:44 AM
                          Compile timeMark Roulo2010/06/27 10:12 AM
                          Compile timeMark Roulo2010/06/27 10:21 AM
                            Compile timeEduardoS2010/06/27 11:37 AM
                            Compile timeRichard Cownie2010/06/27 04:07 PM
                              Compile time & efficiency?2010/06/28 12:03 AM
                                Compile time & efficiencyMark Christiansen2010/06/28 06:08 AM
                                Compile time & efficiencyLinus Torvalds2010/06/28 07:48 AM
                                  kernel programming languageJohn Simon2010/06/29 06:46 PM
                                Compile time & efficiencyRichard Cownie2010/06/28 09:29 AM
                                  Compile time & efficiencyLinus Torvalds2010/06/28 11:17 AM
                                    Compile time & efficiencyRichard Cownie2010/06/28 02:16 PM
                                      Compile time & efficiencyRichard Cownie2010/06/28 06:23 PM
                                        Compile time & efficiencyMark Roulo2010/06/29 08:31 AM
                                          Compile time & efficiencyRichard Cownie2010/06/29 11:48 AM
                                          Compile time & efficiencyrwessel2010/06/29 12:28 PM
                                            C is a crappydev2010/06/29 07:12 PM
                                              C is a crappy, but only when you push it out of it's nicheRohit2010/06/30 02:11 AM
                                              C is a crappyanon2010/06/30 02:17 AM
                                                C is a crappydev2010/06/30 07:59 AM
                                                  C is a crappyMax2010/07/01 04:30 AM
                                                    C is a crappyMichael S2010/07/01 07:00 AM
                                                      C is a crappyKonrad Schwarz2010/07/01 08:02 AM
                                                        C is a crappyMichael S2010/07/01 08:50 AM
                                                          C isn't so crappyanon2010/07/01 10:11 AM
                                                            C isn't so crappyMikael Tillenius2010/07/01 11:39 AM
                                                          C is a crappyKonrad Schwarz2010/07/01 11:22 AM
                                                          C is a crappyMax2010/07/02 08:44 AM
                                                            C is a crappyrwessel2010/07/02 12:33 PM
                                                              C is a crappyanon2010/07/02 01:17 PM
                                                              C is a crappyMax2010/07/02 02:56 PM
                                                                C is a crappyMax2010/07/02 03:13 PM
                                                                  C is a crappyrwessel2010/07/02 03:32 PM
                                                                    C is a crappyMax2010/07/02 04:19 PM
                                                                    C is a crappyGabriele Svelto2010/07/05 05:25 AM
                                                      C is a crappygallier22010/07/02 12:14 AM
                                                    C is a crappyIan Ollmann2010/07/06 03:07 PM
                                                      PortabilityMax2010/07/06 03:37 PM
                                                      C is a crappyhobold2010/07/07 02:31 AM
                                                        C is a crappyIan Ollmann2010/07/07 05:18 PM
                                                      failure to standardize typesCarlie Coats2010/07/07 04:11 AM
                                                      C is a crappyKonrad Schwarz2010/07/07 08:34 AM
                                                        C is a crappyIan Ollmann2010/07/07 05:29 PM
                                                          C is a crappy NOTKonrad Schwarz2010/07/08 12:29 AM
                                                  C is a crappyanon2010/07/01 10:40 PM
                                                    C type safety?2010/07/02 01:10 AM
                                                      C type safetyanon2010/07/02 11:02 PM
                                                    C is a crappydev2010/07/03 04:51 PM
                                                      C is a crappyanon2010/07/03 07:02 PM
                                                        C is a crappydev2010/07/05 07:27 AM
                                                          C is a crappy?2010/07/05 09:05 AM
                                                            C is a crappyanonymous2010/07/07 08:32 AM
                                                              C is a crappy?2010/07/07 10:48 PM
                                                              C is a crappyAnon2010/07/08 12:53 AM
                                                      C is a crappy and a crappie is a fishanonymous2010/07/03 07:24 PM
                                      Compile time & efficiencyMichael S2010/06/29 03:18 AM
                                        Compile time & efficiencyrwessel2010/06/29 12:20 PM
                                        Compile time & efficiencysomeone2010/06/30 11:03 AM
                                        Compile time & efficiencyJouni Osmala2010/07/02 05:29 AM
                                  Compile time & efficiencyMax2010/06/28 05:05 PM
                                    Compile time & efficiencyEduardoS2010/06/28 05:11 PM
                                    Compile time & efficiencyMichael S2010/06/29 03:33 AM
                              Compile timeFoo_2010/06/28 09:03 AM
          sun 's cc better than GCC?Silent2010/06/23 06:19 PM
            sun 's cc better than GCC?Foo_2010/06/23 07:06 PM
          sun 's cc better than GCC?Andi Kleen2010/06/24 02:49 AM
        sun 's versus gccVincent Diepeveen2010/06/23 03:07 PM
    Why no GCC?Carlie Coats2010/06/23 05:11 AM
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