* config/i386/i386.c (build_processor_model_struct): New function.
(make_var_decl): New function.
(fold_builtin_cpu): New function.
(ix86_fold_builtin): New function.
(make_cpu_type_builtin): New function.
(ix86_init_platform_type_builtins): New function.
(ix86_expand_builtin): Expand new builtins by folding them.
(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 symbol __cpu_model.