Author: Pavel Kosov Date: 2024-03-27T03:25:33+03:00 New Revision: 373d8755140df0c760e9c292c5f88479cdda6f4c
URL: https://github.com/llvm/llvm-project/commit/373d8755140df0c760e9c292c5f88479cdda6f4c DIFF: https://github.com/llvm/llvm-project/commit/373d8755140df0c760e9c292c5f88479cdda6f4c.diff LOG: [cfi][CodeGen] Call SetLLVMFunctionAttributes{,ForDefinition} on __cf… (#78253) …i_check This causes __cfi_check, just as __cfi_check_fail, to get the proper target-specific attributes, in particular uwtable for unwind table generation. Previously, nounwind attribute could be inferred for __cfi_check, which caused it to lose its unwind table even with -funwind-table option. ~~ Huawei RRI, OS Lab Co-authored-by: Nikolai Kholiavin <kholiavin.niko...@huawei-partners.com> Added: clang/test/CodeGen/cfi-check-attrs.c Modified: clang/docs/ReleaseNotes.rst clang/lib/CodeGen/CGExpr.cpp clang/test/CodeGen/cfi-check-fail.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 01abe2b39e876b..0dd026a5de5c6f 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -626,6 +626,10 @@ Sanitizers manually disable potentially noisy signed integer overflow checks with ``-fno-sanitize=signed-integer-overflow`` +- ``-fsanitize=cfi -fsanitize-cfi-cross-dso`` (cross-DSO CFI instrumentation) + now generates the ``__cfi_check`` function with proper target-specific + attributes, for example allowing unwind table generation. + Python Binding Changes ---------------------- diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp index 85f5d739cef457..6491835cf8ef17 100644 --- a/clang/lib/CodeGen/CGExpr.cpp +++ b/clang/lib/CodeGen/CGExpr.cpp @@ -3663,12 +3663,29 @@ void CodeGenFunction::EmitCfiSlowPathCheck( // symbol in LTO mode. void CodeGenFunction::EmitCfiCheckStub() { llvm::Module *M = &CGM.getModule(); - auto &Ctx = M->getContext(); + ASTContext &C = getContext(); + QualType QInt64Ty = C.getIntTypeForBitwidth(64, false); + + FunctionArgList FnArgs; + ImplicitParamDecl ArgCallsiteTypeId(C, QInt64Ty, ImplicitParamKind::Other); + ImplicitParamDecl ArgAddr(C, C.VoidPtrTy, ImplicitParamKind::Other); + ImplicitParamDecl ArgCFICheckFailData(C, C.VoidPtrTy, + ImplicitParamKind::Other); + FnArgs.push_back(&ArgCallsiteTypeId); + FnArgs.push_back(&ArgAddr); + FnArgs.push_back(&ArgCFICheckFailData); + const CGFunctionInfo &FI = + CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, FnArgs); + llvm::Function *F = llvm::Function::Create( - llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false), + llvm::FunctionType::get(VoidTy, {Int64Ty, VoidPtrTy, VoidPtrTy}, false), llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M); + CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false); + CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F); F->setAlignment(llvm::Align(4096)); CGM.setDSOLocal(F); + + llvm::LLVMContext &Ctx = M->getContext(); llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F); // CrossDSOCFI pass is not executed if there is no executable code. SmallVector<llvm::Value*> Args{F->getArg(2), F->getArg(1)}; diff --git a/clang/test/CodeGen/cfi-check-attrs.c b/clang/test/CodeGen/cfi-check-attrs.c new file mode 100644 index 00000000000000..375aa30074d887 --- /dev/null +++ b/clang/test/CodeGen/cfi-check-attrs.c @@ -0,0 +1,5 @@ +// RUN: %clang_cc1 -triple arm-unknown-linux -funwind-tables=1 -fsanitize-cfi-cross-dso -emit-llvm -o - %s | FileCheck %s + +// CHECK: define weak {{.*}}void @__cfi_check({{.*}} [[ATTR:#[0-9]*]] + +// CHECK: attributes [[ATTR]] = {{.*}} uwtable(sync) diff --git a/clang/test/CodeGen/cfi-check-fail.c b/clang/test/CodeGen/cfi-check-fail.c index 2f12cee9dec602..15f6c77abf2b20 100644 --- a/clang/test/CodeGen/cfi-check-fail.c +++ b/clang/test/CodeGen/cfi-check-fail.c @@ -72,7 +72,7 @@ void caller(void (*f)(void)) { // CHECK: [[CONT5]]: // CHECK: ret void -// CHECK: define weak void @__cfi_check(i64 %[[TYPE:.*]], ptr %[[ADDR:.*]], ptr %[[DATA:.*]]) align 4096 +// CHECK: define weak void @__cfi_check(i64 noundef %[[TYPE:.*]], ptr noundef %[[ADDR:.*]], ptr noundef %[[DATA:.*]]){{.*}} align 4096 // CHECK-NOT: } // CHECK: call void @__cfi_check_fail(ptr %[[DATA]], ptr %[[ADDR]]) // CHECK-NEXT: ret void _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
