https://github.com/jroelofs created https://github.com/llvm/llvm-project/pull/81167
We should only warn if the default version is the one that is unused. Fixes: https://github.com/llvm/llvm-project/issues/80227 >From 96e3020eaa69f7f14b67617a250df3041cc1996b Mon Sep 17 00:00:00 2001 From: Jon Roelofs <jonathan_roel...@apple.com> Date: Thu, 8 Feb 2024 10:02:50 -0800 Subject: [PATCH] [clang][sema] Fix -Wunused-function on target_version'd file-scope functions We should only warn if the default version is the one that is unused. Fixes: https://github.com/llvm/llvm-project/issues/80227 --- clang/include/clang/AST/Decl.h | 4 ++++ clang/lib/AST/Decl.cpp | 5 +++++ clang/lib/Sema/Sema.cpp | 2 +- clang/test/SemaCXX/warn-unused-filescoped.cpp | 16 ++++++++++++++++ 4 files changed, 26 insertions(+), 1 deletion(-) diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h index f26fb5ad5f133..854e466cfd6b0 100644 --- a/clang/include/clang/AST/Decl.h +++ b/clang/include/clang/AST/Decl.h @@ -2615,6 +2615,10 @@ class FunctionDecl : public DeclaratorDecl, /// the target functionality. bool isTargetMultiVersion() const; + /// True if this function is the default version of a multiversioned dispatch + /// function as a part of the target functionality. + bool isTargetMultiVersionDefault() const; + /// True if this function is a multiversioned dispatch function as a part of /// the target-clones functionality. bool isTargetClonesMultiVersion() const; diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp index 26fdfa040796e..8a79f5c0b04f7 100644 --- a/clang/lib/AST/Decl.cpp +++ b/clang/lib/AST/Decl.cpp @@ -3537,6 +3537,11 @@ bool FunctionDecl::isTargetMultiVersion() const { (hasAttr<TargetAttr>() || hasAttr<TargetVersionAttr>()); } +bool FunctionDecl::isTargetMultiVersionDefault() const { + return isMultiVersion() && hasAttr<TargetVersionAttr>() && + getAttr<TargetVersionAttr>()->isDefaultVersion(); +} + bool FunctionDecl::isTargetClonesMultiVersion() const { return isMultiVersion() && hasAttr<TargetClonesAttr>(); } diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp index 2d4e6d1d058cd..58cbcc30e098a 100644 --- a/clang/lib/Sema/Sema.cpp +++ b/clang/lib/Sema/Sema.cpp @@ -1393,7 +1393,7 @@ void Sema::ActOnEndOfTranslationUnit() { Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl) << /*function=*/0 << DiagD << DiagRange; } - } else { + } else if (!FD->isTargetMultiVersion() || FD->isTargetMultiVersionDefault()) { if (FD->getDescribedFunctionTemplate()) Diag(DiagD->getLocation(), diag::warn_unused_template) << /*function=*/0 << DiagD << DiagRange; diff --git a/clang/test/SemaCXX/warn-unused-filescoped.cpp b/clang/test/SemaCXX/warn-unused-filescoped.cpp index be8d350855c07..0c347e9e19c9d 100644 --- a/clang/test/SemaCXX/warn-unused-filescoped.cpp +++ b/clang/test/SemaCXX/warn-unused-filescoped.cpp @@ -236,4 +236,20 @@ constexpr int constexpr4() { return 2; } #endif } +__attribute__((target_version("fp16"))) +static int not_used_fmv(void) { return 1; } +__attribute__((target_version("fp16fml"))) +static int not_used_fmv(void) { return 2; } +__attribute__((target_version("default"))) +static int not_used_fmv(void) { return 0; } // expected-warning {{unused function 'not_used_fmv'}} + + +__attribute__((target_version("fp16"))) +static int definitely_used_fmv(void) { return 1; } +__attribute__((target_version("fp16fml"))) +static int definitely_used_fmv(void) { return 2; } +__attribute__((target_version("default"))) +static int definitely_used_fmv(void) { return 0; } +int definite_user(void) { return definitely_used_fmv(); } + #endif _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits