1 files changed, 54 insertions, 0 deletions
diff --git a/lib/CodeGen/CoreCLRGC.cpp b/lib/CodeGen/CoreCLRGC.cpp
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+++ b/lib/CodeGen/CoreCLRGC.cpp
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+//===-- CoreCLRGC.cpp - CoreCLR Runtime GC Strategy -----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a GCStrategy for the CoreCLR Runtime.
+// The strategy is similar to Statepoint-example GC, but differs from it in
+// certain aspects, such as:
+// 1) Base-pointers need not be explicitly tracked and reported for
+//    interior pointers
+// 2) Uses a different format for encoding stack-maps
+// 3) Location of Safe-point polls: polls are only needed before loop-back edges
+//    and before tail-calls (not needed at function-entry)
+//
+// The above differences in behavior are to be implemented in upcoming checkins.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/GCStrategy.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Value.h"
+
+using namespace llvm;
+
+namespace {
+class CoreCLRGC : public GCStrategy {
+public:
+  CoreCLRGC() {
+    UseStatepoints = true;
+    // These options are all gc.root specific, we specify them so that the
+    // gc.root lowering code doesn't run.
+    InitRoots = false;
+    NeededSafePoints = 0;
+    UsesMetadata = false;
+    CustomRoots = false;
+  }
+  Optional<bool> isGCManagedPointer(const Value *V) const override {
+    // Method is only valid on pointer typed values.
+    PointerType *PT = cast<PointerType>(V->getType());
+    // We pick addrspace(1) as our GC managed heap.
+    return (1 == PT->getAddressSpace());
+  }
+};
+}
+
+static GCRegistry::Add<CoreCLRGC> X("coreclr", "CoreCLR-compatible GC");
+
+namespace llvm {
+void linkCoreCLRGC() {}
+}