--- /dev/null
+//===-- llvm/Annotation.h - Annotation classes -------------------*- C++ -*--=//
+//
+// This file contains the declarations for two classes: Annotation & Annotable.
+// Using these two simple classes, anything that derives from Annotable can have
+// Annotation subclasses attached to them, ready for easy retrieval.
+//
+// Annotations are designed to be easily attachable to LLVM code (as all Value's
+// are Annotable), and can even be serialized to bytecode and to assembly.
+//
+// The AnnotationManager class (defined in AnnotationManager.h) is essential for
+// using these classes. It is responsible for turning Annotation name strings
+// into tokens [unique id #'s] that may be used to search for and create
+// annotations.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANNOTATION_H
+#define LLVM_ANNOTATION_H
+
+#include <string>
+class AnnotationID;
+class Annotation;
+class Annotable;
+class AnnotationManager;
+
+//===----------------------------------------------------------------------===//
+//
+// AnnotationID - This class is a thin wrapper around an unsigned integer that
+// is used to hopefully prevent errors using AnnotationID's. They may be copied
+// freely around and passed byvalue with little or no overhead.
+//
+class AnnotationID {
+ friend class AnnotationManager;
+ unsigned ID;
+
+ AnnotationID(); // Default ctor is disabled
+ inline AnnotationID(unsigned i) : ID(i) {} // Only creatable from AnnMgr
+public:
+ inline AnnotationID(const AnnotationID &A) : ID(A.ID) {}
+
+ inline bool operator==(const AnnotationID &A) const {
+ return A.ID == ID;
+ }
+ inline bool operator<(const AnnotationID &A) const {
+ return ID < A.ID;
+ }
+};
+
+
+//===----------------------------------------------------------------------===//
+//
+// Annotation Class - This class serves as a base class for any specific
+// annotations that you might need. Simply subclass this to add extra
+// information to the annotations.
+//
+class Annotation {
+ friend class Annotable; // Annotable manipulates Next list
+ AnnotationID ID; // ID number, as obtained from AnnotationManager
+ Annotation *Next; // The next annotation in the linked list
+public:
+ inline Annotation(AnnotationID id) : ID(id), Next(0) {}
+ virtual ~Annotation() {} // Designed to be subclassed
+
+ // getID - Return the unique ID# of this annotation
+ inline AnnotationID getID() const { return ID; }
+
+ // getNext - Return the next annotation in the list...
+ inline Annotation *getNext() const { return Next; }
+};
+
+
+//===----------------------------------------------------------------------===//
+//
+// Annotable - This class is used as a base class for all objects that would
+// like to have annotation capability. One notable subclass is Value, which
+// means annotations can be attached to almost everything in LLVM.
+//
+// Annotable objects keep their annotation list sorted as annotations are
+// inserted and deleted. This is used to ensure that annotations with identical
+// ID#'s are stored sequentially.
+//
+class Annotable {
+ Annotation *AnnotationList;
+public:
+ Annotable() : AnnotationList(0) {}
+ virtual ~Annotable() { // Virtual because it's designed to be subclassed...
+ Annotation *A = AnnotationList;
+ while (A) {
+ Annotation *Next = A->getNext();
+ delete A;
+ A = Next;
+ }
+ }
+
+ // getAnnotation - Search the list for annotations of the specified ID. The
+ // pointer returned is either null (if no annotations of the specified ID
+ // exist), or it points to the first element of a potentially list of elements
+ // with identical ID #'s.
+ //
+ Annotation *getAnnotation(AnnotationID ID) const {
+ for (Annotation *A = AnnotationList; A; A = A->getNext())
+ if (A->getID() == ID) return A;
+ return 0;
+ }
+
+ // getOrCreateAnnotation - Search through the annotation list, if there is
+ // no annotation with the specified ID, then use the AnnotationManager to
+ // create one.
+ //
+ inline Annotation *getOrCreateAnnotation(AnnotationID ID);
+
+ // addAnnotation - Insert the annotation into the list in a sorted location.
+ //
+ void addAnnotation(Annotation *A) {
+ assert(A->Next == 0 && "Annotation already in list?!?");
+
+ Annotation **AL = &AnnotationList;
+ while (*AL && (*AL)->ID < A->getID()) // Find where to insert annotation
+ AL = &((*AL)->Next);
+ A->Next = *AL; // Link the annotation in
+ *AL = A;
+ }
+
+ // unlinkAnnotation - Remove the first annotation of the specified ID... and
+ // then return the unlinked annotation. The annotation object is not deleted.
+ //
+ inline Annotation *unlinkAnnotation(AnnotationID ID) {
+ for (Annotation **A = &AnnotationList; *A; A = &((*A)->Next))
+ if ((*A)->getID() == ID) {
+ Annotation *Ret = *A;
+ *A = Ret->Next;
+ Ret->Next = 0;
+ return Ret;
+ }
+ return 0;
+ }
+
+ // deleteAnnotation - Delete the first annotation of the specified ID in the
+ // list. Unlink unlinkAnnotation, this actually deletes the annotation object
+ //
+ bool deleteAnnotation(AnnotationID ID) {
+ Annotation *A = unlinkAnnotation(ID);
+ delete A;
+ return A != 0;
+ }
+};
+
+
+//===----------------------------------------------------------------------===//
+//
+// AnnotationManager - This class is primarily responsible for maintaining a
+// one-to-one mapping between string Annotation names and Annotation ID numbers.
+//
+// Compared to the rest of the Annotation system, these mapping methods are
+// relatively slow, so they should be avoided by locally caching Annotation
+// ID #'s. These methods are safe to call at any time, even by static ctors, so
+// they should be used by static ctors most of the time.
+//
+// This class also provides support for annotations that are created on demand
+// by the Annotable::getOrCreateAnnotation method. To get this to work, simply
+// register an annotation handler
+//
+struct AnnotationManager {
+ //===--------------------------------------------------------------------===//
+ // Basic ID <-> Name map functionality
+
+ static AnnotationID getID (const string &Name); // Name -> ID
+ static const string &getName(AnnotationID ID); // ID -> Name
+
+
+ //===--------------------------------------------------------------------===//
+ // Annotation creation on demand support...
+
+ // registerAnnotationFactory - This method is used to register a callback
+ // function used to create an annotation on demand if it is needed by the
+ // Annotable::getOrCreateAnnotation method.
+ //
+ static void registerAnnotationFactory(AnnotationID ID,
+ Annotation *(*Func)(AnnotationID, Annotable *));
+
+ // createAnnotation - Create an annotation of the specified ID for the
+ // specified object, using a register annotation creation function.
+ //
+ static Annotation *createAnnotation(AnnotationID ID, Annotable *Obj);
+};
+
+
+
+// getOrCreateAnnotation - Search through the annotation list, if there is
+// no annotation with the specified ID, then use the AnnotationManager to
+// create one.
+//
+inline Annotation *Annotable::getOrCreateAnnotation(AnnotationID ID) {
+ Annotation *A = getAnnotation(ID); // Fast path, check for preexisting ann
+ if (A) return A;
+
+ // No annotation found, ask the annotation manager to create an annotation...
+ A = AnnotationManager::createAnnotation(ID, this);
+ assert(A && "AnnotationManager could not create annotation!");
+ addAnnotation(A);
+ return A;
+}
+
+#endif
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