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diff --git a/include/llvm/Transforms/IPO/FunctionAttrs.h b/include/llvm/Transforms/IPO/FunctionAttrs.h
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+//===-- FunctionAttrs.h - Compute function attrs --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// Provides passes for computing function attributes based on interprocedural
+/// analyses.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_IPO_FUNCTIONATTRS_H
+#define LLVM_TRANSFORMS_IPO_FUNCTIONATTRS_H
+
+#include "llvm/Analysis/LazyCallGraph.h"
+#include "llvm/Analysis/CGSCCPassManager.h"
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+/// Computes function attributes in post-order over the call graph.
+///
+/// By operating in post-order, this pass computes precise attributes for
+/// called functions prior to processsing their callers. This "bottom-up"
+/// approach allows powerful interprocedural inference of function attributes
+/// like memory access patterns, etc. It can discover functions that do not
+/// access memory, or only read memory, and give them the readnone/readonly
+/// attribute. It also discovers function arguments that are not captured by
+/// the function and marks them with the nocapture attribute.
+struct PostOrderFunctionAttrsPass : PassInfoMixin<PostOrderFunctionAttrsPass> {
+  PreservedAnalyses run(LazyCallGraph::SCC &C, CGSCCAnalysisManager &AM);
+};
+
+/// Create a legacy pass manager instance of a pass to compute function attrs
+/// in post-order.
+Pass *createPostOrderFunctionAttrsLegacyPass();
+
+/// A pass to do RPO deduction and propagation of function attributes.
+///
+/// This pass provides a general RPO or "top down" propagation of
+/// function attributes. For a few (rare) cases, we can deduce significantly
+/// more about function attributes by working in RPO, so this pass
+/// provides the compliment to the post-order pass above where the majority of
+/// deduction is performed.
+// FIXME: Currently there is no RPO CGSCC pass structure to slide into and so
+// this is a boring module pass, but eventually it should be an RPO CGSCC pass
+// when such infrastructure is available.
+class ReversePostOrderFunctionAttrsPass
+    : public PassInfoMixin<ReversePostOrderFunctionAttrsPass> {
+public:
+  PreservedAnalyses run(Module &M, AnalysisManager<Module> &AM);
+};
+}
+
+#endif // LLVM_TRANSFORMS_IPO_FUNCTIONATTRS_H