https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118313
--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Alfie Richards <alfiericha...@gcc.gnu.org>: https://gcc.gnu.org/g:aeb9a43bbb2e92d5e4b93250785701d0e37355d9 commit r16-4039-gaeb9a43bbb2e92d5e4b93250785701d0e37355d9 Author: Alfie Richards <alfie.richa...@arm.com> Date: Thu Feb 13 15:30:45 2025 +0000 fmv: c++: Change target_version semantics to follow ACLE specification. This patch changes the semantics of target_version and target_clones attributes to match the behavior described in the Arm C Language extension. The changes to behavior are: - The scope and signature of an FMV function set is now that of the default version. - The FMV resolver is now created at the locations of the default version implementation. Previously this was at the first call to an FMV function. - When a TU has a single annotated function version, it gets mangled. - This includes a lone annotated default version. This only affects targets with TARRGET_HAS_FMV_TARGET_ATTRIBUTE set to false. Currently that is aarch64 and riscv. This is achieved by: - Skipping the existing FMV dispatching code at C++ gimplification and instead making use of the target_clones dispatching code in multiple_targets.cc. (This fixes PR target/118313 for aarch64 and riscv). - Splitting target_clones pass in two, an early and late pass, where the early pass handles cases where multiple declarations are used to define a version, and the late pass handling target semantics targets, and cases where a FMV set is defined by a single target_clones decl. - Changing the logic in add_candidates and resolve_address of overloaded function to prevent resolution of any version except a default version. (thus making the default version determine scope and signature of the versioned function set). - Adding logic for dispatching a lone annotated default version in multiple_targets.cc - As as annotated default version gets mangled an alias is created from the dispatched symbol to the default version as no ifunc resolution is required in this case. (ie. an alias from `_Z3foov` to `_Z3foov.default`) - Adding logic to `symbol_table::remove_unreachable_nodes` and analyze_functions that a reference to the default function version also implies a possible reference to the other versions (so they shouldnt be deleted and do need to be analyzed). gcc/ChangeLog: PR target/118313 * cgraph.cc (delete_function_version): Made public static member of cgraph_node. * cgraph.h (delete_function_version): Ditto. * cgraphunit.cc (analyze_functions): Add logic for target version dependencies. * ipa.cc (symbol_table::remove_unreachable_nodes): Ditto. * multiple_target.cc (create_dispatcher_calls): Change to support target version semantics. (ipa_target_clone): Change to dispatch all function sets in target_version semantics, and to have early and late pass. (expand_target_clones): Add logic for cases of target_clones with no defaults. (is_simple_target_clones_case): New function. (class pass_target_clone): New parameter for early or late pass. * config/aarch64/aarch64.cc: (aarch64_get_function_versions_dispatcher): Refactor with the assumption that the DECL node will be default. * config/riscv/riscv.cc: (riscv_get_function_versions_dispatcher): Refactor with the assumption that the DECL node will be default. * passes.def: Split target_clones pass into early and late version. gcc/cp/ChangeLog: PR target/118313 * call.cc (add_candidates): Change to not resolve non-default versions in target_version semantics. * class.cc (resolve_address_of_overloaded_function): Ditto. * cp-gimplify.cc (cp_genericize_r): Change logic to not apply for target_version semantics. * decl.cc (maybe_mark_function_versioned): Remove static. * cp-tree.h (maybe_mark_function_versioned): New function. * decl2.cc (cplus_decl_attributes ): Change to mark and therefore mangle all target_version decls in target_version semantics. * typeck.cc (cp_build_function_call_vec): Add error for calling unresolvable non-default node in target_version semantics. gcc/testsuite/ChangeLog: * g++.target/aarch64/mv-1.C: Change for target_version semantics. * g++.target/aarch64/mv-symbols2.C: Ditto. * g++.target/aarch64/mv-symbols3.C: Ditto. * g++.target/aarch64/mv-symbols4.C: Ditto. * g++.target/aarch64/mv-symbols5.C: Ditto. * g++.target/aarch64/mvc-symbols3.C: Ditto. * g++.target/riscv/mv-symbols2.C: Ditto. * g++.target/riscv/mv-symbols3.C: Ditto. * g++.target/riscv/mv-symbols4.C: Ditto. * g++.target/riscv/mv-symbols5.C: Ditto. * g++.target/riscv/mvc-symbols3.C: Ditto. * g++.target/aarch64/mv-symbols10.C: New test. * g++.target/aarch64/mv-symbols11.C: New test. * g++.target/aarch64/mv-symbols12.C: New test. * g++.target/aarch64/mv-symbols13.C: New test. * g++.target/aarch64/mv-symbols6.C: New test. * g++.target/aarch64/mv-symbols7.C: New test. * g++.target/aarch64/mv-symbols8.C: New test. * g++.target/aarch64/mv-symbols9.C: New test.
