[clang] Set function attributes on SEH filter functions correctly.

[sanwou01]

Summary

When compiling with -munwind-tables, the SEH filter funclet needs the uwtable
function attribute, which gets automatically added if we use
SetInternalFunctionAttributes. The filter funclet is internal so this seems
appropriate.

[rnk]

Thanks, the code change looks good, but please adjust the tests a bit.

clang/test/CodeGen/exceptions-seh-finally.c

284–286

We shouldn't be marking this thing noinline. I believe it appears because clang applies noinline everywhere at O0. Please add -O1 -disable-llvm-passes to the RUN line so that it doesn't appear. The appearance of nounwind should be expected, so keep that here.

clang/test/CodeGenCXX/exceptions-seh-filter-uwtable.cpp

2

Is "arm64-windowsj" a typo? Also, please add -O1 -disable-llvm-passes as above.

[sanwou01]

Fix tests, thanks rnk

[rnk]

lgtm, just some test comment tweaks.

clang/test/CodeGen/exceptions-seh-finally.c

3

I guess it would be best to move the comment about why we pass -O1 -disable-llvm-passes here. We are doing it to avoid applying optnone and noinline attributes everywhere.

284–286

Please leave at least "Look for the absence of noinline." from the original comment. I think I added this test because we used to mark these noinline.

clang/lib/CodeGen/CGException.cpp

llvm::Function *Fn = llvm::Function::Create(
       FnTy, llvm::GlobalValue::InternalLinkage, Name.str(), &CGM.getModule());
 
   IsOutlinedSEHHelper = true;
 
   StartFunction(GlobalDecl(), RetTy, Fn, FnInfo, Args,
                 OutlinedStmt->getBeginLoc(), OutlinedStmt->getBeginLoc());
   CurSEHParent = ParentCGF.CurSEHParent;
 
-  CGM.SetLLVMFunctionAttributes(GlobalDecl(), FnInfo, CurFn);
+  CGM.SetInternalFunctionAttributes(GlobalDecl(), CurFn, FnInfo);
   EmitCapturedLocals(ParentCGF, OutlinedStmt, IsFilter);
 }
 
 /// Create a stub filter function that will ultimately hold the code of the
 /// filter expression. The EH preparation passes in LLVM will outline the code
 /// from the main function body into this stub.
 llvm::Function *
 CodeGenFunction::GenerateSEHFilterFunction(CodeGenFunction &ParentCGF,

clang/test/CodeGen/exceptions-seh-finally.c

-// RUN: %clang_cc1 %s -triple x86_64-pc-win32 -fms-extensions -emit-llvm -o - | FileCheck %s
-// RUN: %clang_cc1 %s -triple i686-pc-win32 -fms-extensions -emit-llvm -o - | FileCheck %s
-// RUN: %clang_cc1 %s -triple aarch64-windows -fms-extensions -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple x86_64-pc-win32 -fms-extensions -emit-llvm -O1 -disable-llvm-passes -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple i686-pc-win32 -fms-extensions -emit-llvm -O1 -disable-llvm-passes -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple aarch64-windows -fms-extensions -emit-llvm -O1 -disable-llvm-passes -o - | FileCheck %s
+// NOTE: we're passing "-O1 -disable-llvm-passes" to avoid adding optnone and noinline everywhere.
 
 void abort(void) __attribute__((noreturn));
 void might_crash(void);
 void cleanup(void);
 int check_condition(void);
 void basic_finally(void) {
   __try {
     might_crash();
void finally_with_func() {
   } __finally {
     cleanup_with_func(__func__);
   }
 }
 
 // CHECK-LABEL: define internal void @"?fin$0@0@finally_with_func@@"({{[^)]*}})
 // CHECK: call void @cleanup_with_func(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @"??_C@_0BC@COAGBPGM@finally_with_func?$AA@", i{{32|64}} 0, i{{32|64}} 0))
 
-// Look for the absence of noinline. Enum attributes come first, so check that
-// a string attribute is the first to verify that no enum attributes are
-// present.
-// CHECK: attributes [[finally_attrs]] = { "{{.*}}" }
+// Look for the absence of noinline.  nounwind is expected; any further
+// attributes should be string attributes.
+// CHECK: attributes [[finally_attrs]] = { nounwind "{{.*}}" }

clang/test/CodeGenCXX/exceptions-seh-filter-uwtable.cpp

+// RUN: %clang_cc1 "-triple" "arm64-windows" "-munwind-tables" "-fms-compatibility" -emit-llvm -O1 -disable-llvm-passes %s -o - | FileCheck %s
+// NOTE: we're passing "-O1 -disable-llvm-passes" to avoid adding optnone and noinline everywhere.
+
+# 0 "" 3
+#define a(b, c) d() & b
+#define f(c) a(e(0, 0, #c).b(), )
+
+struct e {
+  e(int, int, char *);
+  int b();
+};
+
+struct d {
+  void operator&(int);
+};
+
+struct h;
+
+struct i {
+  h *operator->();
+  h &operator*() { f(); }
+};
+
+typedef int g;
+
+struct h {
+  void ad();
+};
+
+g aq(h j, g k, int, int) {
+  if (k)
+    return;
+  j.ad();
+}
+
+// Check for the uwtable attribute on the filter funclet.
+// CHECK: define internal i32 @"?filt$0@0@at@@"(i8* %exception_pointers, i8* %frame_pointer) #[[MD:[0-9]+]]
+// CHECK: attributes #[[MD]] = { nounwind uwtable
+
+void at() {
+  i ar;
+
+  __try {
+    ar->ad();
+  } __except (aq(*ar, _exception_code(), 0, 0)) {
+  }
+
+}