https://github.com/bwendling updated https://github.com/llvm/llvm-project/pull/89126
>From 36ddb5811f11a1f6968705005713f34713026dbb Mon Sep 17 00:00:00 2001 From: Bill Wendling <mo...@google.com> Date: Wed, 17 Apr 2024 12:23:02 -0700 Subject: [PATCH 1/3] [Clang] Handle structs with inner structs and no fields A struct that declares an inner struct, but no fields, won't have a field count. So getting the offset of the inner struct fails. This happens in both C and C++: struct foo { struct bar { int Quantizermatrix[]; }; }; Here 'struct foo' has no fields. --- clang/lib/CodeGen/CGBuiltin.cpp | 15 ++++++++++++- clang/test/CodeGen/attr-counted-by-pr88931.c | 22 +++++++++++++++++++ .../test/CodeGen/attr-counted-by-pr88931.cpp | 21 ++++++++++++++++++ 3 files changed, 57 insertions(+), 1 deletion(-) create mode 100644 clang/test/CodeGen/attr-counted-by-pr88931.c create mode 100644 clang/test/CodeGen/attr-counted-by-pr88931.cpp diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp index a05874e63c73c2..bee12c4469e7f7 100644 --- a/clang/lib/CodeGen/CGBuiltin.cpp +++ b/clang/lib/CodeGen/CGBuiltin.cpp @@ -829,6 +829,9 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField( unsigned FieldNo = 0; bool IsUnion = RD->isUnion(); + if (RD->isImplicit()) + return nullptr; + for (const Decl *D : RD->decls()) { if (const auto *Field = dyn_cast<FieldDecl>(D); Field && (Name.empty() || Field->getNameAsString() == Name) && @@ -844,7 +847,17 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField( if (const FieldDecl *Field = FindFlexibleArrayMemberField(Ctx, Record, Name, Offset)) { const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD); - Offset += Layout.getFieldOffset(FieldNo); + if (Layout.getFieldCount()) { + // A struct that holds only an inner struct won't have any fields. E.g. + // + // struct foo { + // struct bar { + // int count; + // int array[]; + // }; + // }; + Offset += Layout.getFieldOffset(FieldNo); + } return Field; } diff --git a/clang/test/CodeGen/attr-counted-by-pr88931.c b/clang/test/CodeGen/attr-counted-by-pr88931.c new file mode 100644 index 00000000000000..baa1bbc8397456 --- /dev/null +++ b/clang/test/CodeGen/attr-counted-by-pr88931.c @@ -0,0 +1,22 @@ +// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 4 +// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -O2 -Wno-missing-declarations -emit-llvm -o - %s | FileCheck %s + +struct foo { + struct bar { + int count; + int array[] __attribute__((counted_by(count))); + }; +}; + +void init(void * __attribute__((pass_dynamic_object_size(0)))); + +// CHECK-LABEL: define dso_local void @test1( +// CHECK-SAME: ptr noundef [[P:%.*]]) local_unnamed_addr #[[ATTR0:[0-9]+]] { +// CHECK-NEXT: entry: +// CHECK-NEXT: [[ARRAY:%.*]] = getelementptr inbounds i8, ptr [[P]], i64 4 +// CHECK-NEXT: tail call void @init(ptr noundef nonnull [[ARRAY]], i64 noundef -1) #[[ATTR2:[0-9]+]] +// CHECK-NEXT: ret void +// +void test1(struct bar *p) { + init(p->array); +} diff --git a/clang/test/CodeGen/attr-counted-by-pr88931.cpp b/clang/test/CodeGen/attr-counted-by-pr88931.cpp new file mode 100644 index 00000000000000..2a8cc1d07e50d9 --- /dev/null +++ b/clang/test/CodeGen/attr-counted-by-pr88931.cpp @@ -0,0 +1,21 @@ +// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 4 +// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -O2 -Wall -emit-llvm -o - %s | FileCheck %s + +struct foo { + struct bar { + int array[]; + bar(); + }; +}; + +void init(void * __attribute__((pass_dynamic_object_size(0)))); + +// CHECK-LABEL: define dso_local void @_ZN3foo3barC1Ev( +// CHECK-SAME: ptr noundef nonnull align 4 dereferenceable(1) [[THIS:%.*]]) unnamed_addr #[[ATTR0:[0-9]+]] align 2 { +// CHECK-NEXT: entry: +// CHECK-NEXT: tail call void @_Z4initPvU25pass_dynamic_object_size0(ptr noundef nonnull [[THIS]], i64 noundef -1) #[[ATTR2:[0-9]+]] +// CHECK-NEXT: ret void +// +foo::bar::bar() { + init(array); +} >From fbb22e6aa21961763c3eb1ca45d44e6c8add1ceb Mon Sep 17 00:00:00 2001 From: Bill Wendling <mo...@google.com> Date: Wed, 17 Apr 2024 12:32:27 -0700 Subject: [PATCH 2/3] Reformat --- clang/lib/CodeGen/CGBuiltin.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp index bee12c4469e7f7..e7d2b84da8bc4d 100644 --- a/clang/lib/CodeGen/CGBuiltin.cpp +++ b/clang/lib/CodeGen/CGBuiltin.cpp @@ -848,7 +848,8 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField( FindFlexibleArrayMemberField(Ctx, Record, Name, Offset)) { const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD); if (Layout.getFieldCount()) { - // A struct that holds only an inner struct won't have any fields. E.g. + // A struct that holds only an inner struct won't have any fields. + // E.g. // // struct foo { // struct bar { >From 4c4046f638a4b02f2fcea8a99b37c58a4eb8aba4 Mon Sep 17 00:00:00 2001 From: Bill Wendling <mo...@google.com> Date: Thu, 18 Apr 2024 13:52:58 -0700 Subject: [PATCH 3/3] Improve calculation by focusing only on FieldDecls. --- clang/lib/CodeGen/CGBuiltin.cpp | 34 +++++++++++---------------------- 1 file changed, 11 insertions(+), 23 deletions(-) diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp index e7d2b84da8bc4d..fe8070f9fd2086 100644 --- a/clang/lib/CodeGen/CGBuiltin.cpp +++ b/clang/lib/CodeGen/CGBuiltin.cpp @@ -826,43 +826,31 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField( ASTContext &Ctx, const RecordDecl *RD, StringRef Name, uint64_t &Offset) { const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel = getLangOpts().getStrictFlexArraysLevel(); - unsigned FieldNo = 0; - bool IsUnion = RD->isUnion(); + uint32_t FieldNo = 0; if (RD->isImplicit()) return nullptr; - for (const Decl *D : RD->decls()) { - if (const auto *Field = dyn_cast<FieldDecl>(D); - Field && (Name.empty() || Field->getNameAsString() == Name) && + for (const FieldDecl *FD : RD->fields()) { + if ((Name.empty() || FD->getNameAsString() == Name) && Decl::isFlexibleArrayMemberLike( - Ctx, Field, Field->getType(), StrictFlexArraysLevel, + Ctx, FD, FD->getType(), StrictFlexArraysLevel, /*IgnoreTemplateOrMacroSubstitution=*/true)) { const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD); Offset += Layout.getFieldOffset(FieldNo); - return Field; + return FD; } - if (const auto *Record = dyn_cast<RecordDecl>(D)) - if (const FieldDecl *Field = - FindFlexibleArrayMemberField(Ctx, Record, Name, Offset)) { + QualType Ty = FD->getType(); + if (!Ty->isPointerType() && (Ty->isStructureType() || Ty->isUnionType())) + if (const FieldDecl *Field = FindFlexibleArrayMemberField( + Ctx, Ty->getAsRecordDecl(), Name, Offset)) { const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD); - if (Layout.getFieldCount()) { - // A struct that holds only an inner struct won't have any fields. - // E.g. - // - // struct foo { - // struct bar { - // int count; - // int array[]; - // }; - // }; - Offset += Layout.getFieldOffset(FieldNo); - } + Offset += Layout.getFieldOffset(FieldNo); return Field; } - if (!IsUnion && isa<FieldDecl>(D)) + if (!RD->isUnion()) ++FieldNo; } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits