llvm/bolt/include/bolt/Passes/InstrumentationSummary.h

//===- bolt/Passes/InstrumentationSummary.h ---------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// InstrumentationSummary holds all the data generated during
// the Instrumentation pass, which will be needed latter for runtime library
// binary emit and linking.
//
//===----------------------------------------------------------------------===//

#ifndef BOLT_PASSES_INSTRUMENTATION_SUMMARY_H
#define BOLT_PASSES_INSTRUMENTATION_SUMMARY_H

#include "llvm/ADT/DenseSet.h"
#include <string>
#include <vector>

namespace llvm {

class MCSymbol;

namespace bolt {

class BinaryFunction;

// All structs here are part of the program metadata serialization format and
// consist of POD types or array of POD types that are trivially mapped from
// disk to memory. This provides the runtime library with a basic
// understanding of the program structure, so it can build a CFG for each
// function and deduce execution counts for edges that don't require explicit
// counters. It also provides function names and offsets used when writing the
// fdata file.

// Location information -- analogous to the concept of the same name in fdata
// writing/reading. The difference is that the name is stored as an index to a
// string table written separately.
struct LocDescription { … };

// Inter-function control flow transfer instrumentation
struct CallDescription { … };

// Spans multiple counters during runtime - this is an indirect call site
struct IndCallDescription { … };

// This is an indirect call target (any entry point from any function). This
// is stored sorted in the binary for fast lookups during data writing.
struct IndCallTargetDescription { … };

// Intra-function control flow transfer instrumentation
struct EdgeDescription { … };

// Basic block frequency (CFG node) instrumentation - only used for spanning
// tree leaf nodes.
struct InstrumentedNode { … };

// Entry basic blocks for a function. We record their output addresses to
// check frequency of this address (via node number) against all tracked calls
// to this address and discover traffic coming from uninstrumented code.
struct EntryNode { … };

// Base struct organizing all metadata pertaining to a single function
struct FunctionDescription { … };

/// Holds the summary of the data generated by the Instrumentation Pass.
/// These information will be needed for binary emit.
struct InstrumentationSummary { … };

} // namespace bolt
} // namespace llvm

#endif