llvm-project/llvm/lib/IR/MetadataTracking.cpp

59 lines
1.8 KiB
C++

//===- MetadataTracking.cpp - Implement metadata tracking -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements Metadata tracking.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/MetadataTracking.h"
#include "llvm/IR/Metadata.h"
using namespace llvm;
ReplaceableMetadataImpl *ReplaceableMetadataImpl::get(Metadata &MD) {
if (auto *N = dyn_cast<MDNode>(&MD)) {
if (auto *G = dyn_cast<GenericMDNode>(N))
return G->ReplaceableUses.get();
return cast<MDNodeFwdDecl>(N);
}
return dyn_cast<ValueAsMetadata>(&MD);
}
bool MetadataTracking::track(void *Ref, Metadata &MD, OwnerTy Owner) {
assert(Ref && "Expected live reference");
assert((Owner || *static_cast<Metadata **>(Ref) == &MD) &&
"Reference without owner must be direct");
if (auto *R = ReplaceableMetadataImpl::get(MD)) {
R->addRef(Ref, Owner);
return true;
}
return false;
}
void MetadataTracking::untrack(void *Ref, Metadata &MD) {
assert(Ref && "Expected live reference");
if (auto *R = ReplaceableMetadataImpl::get(MD))
R->dropRef(Ref);
}
bool MetadataTracking::retrack(void *Ref, Metadata &MD, void *New) {
assert(Ref && "Expected live reference");
assert(New && "Expected live reference");
assert(Ref != New && "Expected change");
if (auto *R = ReplaceableMetadataImpl::get(MD)) {
R->moveRef(Ref, New, MD);
return true;
}
return false;
}
bool MetadataTracking::isReplaceable(const Metadata &MD) {
return ReplaceableMetadataImpl::get(const_cast<Metadata &>(MD));
}