Merge rust-lang#28

28: Add the `yk_outline` function attribute. r=ltratt a=vext01



Co-authored-by: Edd Barrett <vext01@gmail.com>

clang/include/clang/Basic/Attr.td

@@ -3823,3 +3823,10 @@ def EnforceTCBLeaf : InheritableAttr {
   let Documentation = [EnforceTCBLeafDocs];
   bit InheritEvenIfAlreadyPresent = 1;
 }
+
+def YkOutline : InheritableAttr {
+  let Spellings = [GCC<"yk_outline">, Declspec<"yk_outline">];
+  let Subjects = SubjectList<[Function]>;
+  let Documentation = [YkOutlineDocs];
+  let SimpleHandler = 1;
+}

clang/include/clang/Basic/AttrDocs.td

@@ -6045,3 +6045,11 @@ def EnforceTCBLeafDocs : Documentation {
   - ``enforce_tcb_leaf(Name)`` indicates that this function is a part of the TCB named ``Name``
   }];
 }
+
+def YkOutlineDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+  The ``yk_outline`` attribute tells the Yk JIT to outline (not inline) calls
+  to the annotated function.
+  }];
+}

clang/lib/CodeGen/CodeGenModule.cpp

@@ -1868,6 +1868,13 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
       B.addAttribute(llvm::Attribute::MinSize);
   }
 
+  if (D->hasAttr<YkOutlineAttr>()) {
+    // Prevent the Yk trace compiler from inlining the call.
+    B.addAttribute("yk_outline");
+    // Prevent LLVM from inlining the call when optimising the trace.
+    B.addAttribute(llvm::Attribute::NoInline);
+  }
+
   F->addAttributes(llvm::AttributeList::FunctionIndex, B);
 
   unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();

clang/test/Misc/pragma-attribute-supported-attributes-list.test

@@ -185,4 +185,5 @@
 // CHECK-NEXT: WorkGroupSizeHint (SubjectMatchRule_function)
 // CHECK-NEXT: XRayInstrument (SubjectMatchRule_function, SubjectMatchRule_objc_method)
 // CHECK-NEXT: XRayLogArgs (SubjectMatchRule_function, SubjectMatchRule_objc_method)
+// CHECK-NEXT: YkOutline (SubjectMatchRule_function)
 // CHECK-NEXT: End of supported attributes.