Hi All, Here is a new version of patch (attached). Bootstrap and make check are in progress (all new tests passed).
New test case g++.dg/ext/mvc4.C fails with ICE, when options lower than "-mavx" are passed. However it has the same behavior if "target_clones" attribute is replaced by 2 corresponding "target" attributes. I've filed PR67946 on this: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67946 Thanks, Evgeny ChangeLog: 2015-10-13 Evgeny Stupachenko <evstu...@gmail.com> gcc/ * Makefile.in (OBJS): Add multiple_target.o. * attrib.c (make_attribute): Moved from config/i386/i386.c * config/i386/i386.c (make_attribute): Deleted. * multiple_target.c (make_attribute): New. (create_dispatcher_calls): Ditto. (get_attr_len): Ditto. (get_attr_str): Ditto. (is_valid_asm_symbol): Ditto. (create_new_asm_name): Ditto. (create_target_clone): Ditto. (expand_target_clones): Ditto. (ipa_target_clone): Ditto. (ipa_dispatcher_calls): Ditto. * passes.def (pass_target_clone): Two new ipa passes. * tree-pass.h (make_pass_target_clone): Ditto. gcc/c-family * c-common.c (handle_target_clones_attribute): New. * (c_common_attribute_table): Add handle_target_clones_attribute. * (handle_always_inline_attribute): Add check on target_clones attribute. * (handle_target_attribute): Ditto. gcc/testsuite * gcc.dg/mvc1.c: New test for multiple targets cloning. * gcc.dg/mvc2.c: Ditto. * gcc.dg/mvc3.c: Ditto. * gcc.dg/mvc4.c: Ditto. * gcc.dg/mvc5.c: Ditto. * gcc.dg/mvc6.c: Ditto. * gcc.dg/mvc7.c: Ditto. * g++.dg/ext/mvc1.C: Ditto. * g++.dg/ext/mvc2.C: Ditto. * g++.dg/ext/mvc3.C: Ditto. * g++.dg/ext/mvc4.C: Ditto. gcc/doc * doc/extend.texi (target_clones): New attribute description. On Sat, Oct 10, 2015 at 12:44 AM, Evgeny Stupachenko <evstu...@gmail.com> wrote: > On Fri, Oct 9, 2015 at 11:04 PM, Jan Hubicka <hubi...@ucw.cz> wrote: >>> On Fri, Oct 9, 2015 at 9:27 PM, Jan Hubicka <hubi...@ucw.cz> wrote: >>> >> >Of course it also depends what you inline into function. You can have >>> >> > >>> >> >bar() target(-mavx) {fancy avx code} >>> >> >foobar() { ...... if (avx) bar();} >>> >> >foo() ctarget(-mavx,-mno-avx) {....foobar();....} >>> >>> "no-" targets are not supported >> >> Why not? I suppose I can use -march=x86_64 in a file compiled with >> -march=core-avx2 or something like that, too. > Sure, you can. target(arch=x86-64) is ok. I mean exactly target(no-avx) > returns: > > aaa.cpp: In function '<built-in>': > aaa.cpp:7:5: error: No dispatcher found for no-avx > int bar() > ^ > >>> >>> >> > >>> >> >Now if you compile with -mavx and because ctarget takes effect only >>> >> >after inlining, >>> >> >at inlining time the target attributes will match and we can edn up >>> >> >inline bar->foobar->foo. >>> >> >After that we multiversion foo and drop AVX flag we will likely get ICE >>> >> >at expansion >>> >> >time. >>> >> But isn't that avoided by fixing up the call graph so that all calls >>> >> to the affected function are going through the dispatcher? Or is >>> >> that happening too late? >>> > >>> > There is dispatcher only for foo that is the root of the callgarph tree. >>> > When inlining we compare target attributes for match (in >>> > can_inline_edge_p). >>> > We do not compare ctarget attributes. Expanding ctarget to target early >>> > would >>> > avoid need for ctarget handling. >>> Currently inlining is disabled for functions with target_clone attribute: >> >> Do you also disable inlining into functions with target_clone? >> What I am concerned about is early inliner inlining (say) AVX code into >> ctarget >> function because at early inlining time the target is not applied, yet. > Right. Now I've got your point and ICE on the test. > Yes the solution is to disable inline into target_clones function. > Or to move the pass creating clones before inline (as you suggested) > and leave dispatcher creator after inline. > > I like you suggestion. It fixes the ICE. > I'll fix the patch and retest. > > Thank you for the review, > Evgeny. > > >> >> Honza
target_clones.patch
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