On Mon, Apr 23, 2012 at 12:16 PM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Mon, Apr 23, 2012 at 6:59 PM, Sriraman Tallam <tmsri...@google.com> wrote: > >>>> i386 maintainers - Is this patch ok? >>> >>> Has the community reached the consensus on how this kind of >>> functionality has to be implemented? I have followed the discussion a >>> bit, but IIRC, there was no clear decision. Without this decision, I >>> am not able to review the _implementation_ of agreed functionality for >>> x86 target. >>> >>> (I apologize if I have missed the decision, please point me to the >>> discussion in this case.) >> >> The discussions are here: >> >> http://gcc.gnu.org/ml/gcc-patches/2011-08/msg01446.html >> and follow-ups to this. >> >> I am not sure about consensus, but the important points raised were: >> >> 1) Constructor ordering: What if some constructors fire before >> cpu_indicator_init?, which determines the CPU. I addressed this >> problem by making the priority of cpu_indicator_init to be the highest >> possible. Still, IFUNC initializers will fire before and they have to >> explicitly call __builtin_cpu_init() before checking the CPU type. >> 2) Reducing the number of builtins : It is only two now. > >> * config/i386/i386.c (build_processor_features_struct): New function. >> (build_processor_model_struct): New function. >> (make_var_decl): New function. >> (get_field_from_struct): New function. >> (fold_builtin_target): New function. >> (ix86_fold_builtin): New function. >> (ix86_expand_builtin): Expand new builtins by folding them. >> (make_cpu_type_builtin): New functions. >> (ix86_init_platform_type_builtins): Make the new builtins. >> (ix86_init_builtins): Make new builtins to detect CPU type. >> (TARGET_FOLD_BUILTIN): New macro. >> (IX86_BUILTIN_CPU_INIT): New enum value. >> (IX86_BUILTIN_CPU_IS): New enum value. >> (IX86_BUILTIN_CPU_SUPPORTS): New enum value. >> * config/i386/i386-builtin-types.def: New function type. >> * testsuite/gcc.target/builtin_target.c: New testcase. >> * doc/extend.texi: Document builtins. >> >> * libgcc/config/i386/i386-cpuinfo.c: New file. >> * libgcc/config/i386/t-cpuinfo: New file. >> * libgcc/config.host: Include t-cpuinfo. >> * libgcc/config/i386/libgcc-glibc.ver: Version symbols __cpu_model >> and __cpu_features. > > The patch is OK. > > I guess that AVX is left as an exercise for a x86 maintainer ;)
I will add AVX, and make all the changes. Thanks, -Sri. > > (I have also CC'd H.J. for his opinion.) > > Thanks, > Uros.
