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//===-- xray-graph.h - XRay Function Call Graph Renderer --------*- 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
//
//===----------------------------------------------------------------------===//
//
// Generate a DOT file to represent the function call graph encountered in
// the trace.
//
//===----------------------------------------------------------------------===//
#ifndef XRAY_GRAPH_H
#define XRAY_GRAPH_H
#include <string>
#include <vector>
#include "func-id-helper.h"
#include "xray-color-helper.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/XRay/Graph.h"
#include "llvm/XRay/Trace.h"
#include "llvm/XRay/XRayRecord.h"
namespace llvm {
namespace xray {
/// A class encapsulating the logic related to analyzing XRay traces, producting
/// Graphs from them and then exporting those graphs for review.
class GraphRenderer {
public:
/// An enum for enumerating the various statistics gathered on latencies
enum class StatType { NONE, COUNT, MIN, MED, PCT90, PCT99, MAX, SUM };
/// An inner struct for common timing statistics information
struct TimeStat {
int64_t Count;
double Min;
double Median;
double Pct90;
double Pct99;
double Max;
double Sum;
std::string getString(StatType T) const;
double getDouble(StatType T) const;
};
using TimestampT = uint64_t;
/// An inner struct for storing edge attributes for our graph. Here the
/// attributes are mainly function call statistics.
///
/// FIXME: expand to contain more information eg call latencies.
struct CallStats {
TimeStat S;
std::vector<TimestampT> Timings;
};
/// An Inner Struct for storing vertex attributes, at the moment just
/// SymbolNames, however in future we could store bulk function statistics.
///
/// FIXME: Store more attributes based on instrumentation map.
struct FunctionStats {
std::string SymbolName;
TimeStat S = {};
};
struct FunctionAttr {
int32_t FuncId;
uint64_t TSC;
};
using FunctionStack = SmallVector<FunctionAttr, 4>;
using PerThreadFunctionStackMap =
DenseMap<llvm::sys::procid_t, FunctionStack>;
class GraphT : public Graph<FunctionStats, CallStats, int32_t> {
public:
TimeStat GraphEdgeMax = {};
TimeStat GraphVertexMax = {};
};
GraphT G;
using VertexIdentifier = typename decltype(G)::VertexIdentifier;
using EdgeIdentifier = decltype(G)::EdgeIdentifier;
/// Use a Map to store the Function stack for each thread whilst building the
/// graph.
///
/// FIXME: Perhaps we can Build this into LatencyAccountant? or vise versa?
PerThreadFunctionStackMap PerThreadFunctionStack;
/// Usefull object for getting human readable Symbol Names.
FuncIdConversionHelper FuncIdHelper;
bool DeduceSiblingCalls = false;
TimestampT CurrentMaxTSC = 0;
/// A private function to help implement the statistic generation functions;
template <typename U>
void getStats(U begin, U end, GraphRenderer::TimeStat &S);
void updateMaxStats(const TimeStat &S, TimeStat &M);
/// Calculates latency statistics for each edge and stores the data in the
/// Graph
void calculateEdgeStatistics();
/// Calculates latency statistics for each vertex and stores the data in the
/// Graph
void calculateVertexStatistics();
/// Normalises latency statistics for each edge and vertex by CycleFrequency;
void normalizeStatistics(double CycleFrequency);
/// An object to color gradients
ColorHelper CHelper;
public:
/// Takes in a reference to a FuncIdHelper in order to have ready access to
/// Symbol names.
explicit GraphRenderer(const FuncIdConversionHelper &FuncIdHelper, bool DSC)
: FuncIdHelper(FuncIdHelper), DeduceSiblingCalls(DSC),
CHelper(ColorHelper::SequentialScheme::OrRd) {
G[0] = {};
}
/// Process an Xray record and expand the graph.
///
/// This Function will return true on success, or false if records are not
/// presented in per-thread call-tree DFS order. (That is for each thread the
/// Records should be in order runtime on an ideal system.)
///
/// FIXME: Make this more robust against small irregularities.
Error accountRecord(const XRayRecord &Record);
const PerThreadFunctionStackMap &getPerThreadFunctionStack() const {
return PerThreadFunctionStack;
}
class Factory {
public:
bool KeepGoing;
bool DeduceSiblingCalls;
std::string InstrMap;
::llvm::xray::Trace Trace;
Expected<GraphRenderer> getGraphRenderer();
};
/// Output the Embedded graph in DOT format on \p OS, labeling the edges by
/// \p T
void exportGraphAsDOT(raw_ostream &OS, StatType EdgeLabel = StatType::NONE,
StatType EdgeColor = StatType::NONE,
StatType VertexLabel = StatType::NONE,
StatType VertexColor = StatType::NONE);
/// Get a reference to the internal graph.
const GraphT &getGraph() { return G; }
};
/// Vector Sum of TimeStats
inline GraphRenderer::TimeStat operator+(const GraphRenderer::TimeStat &A,
const GraphRenderer::TimeStat &B) {
return {A.Count + B.Count, A.Min + B.Min, A.Median + B.Median,
A.Pct90 + B.Pct90, A.Pct99 + B.Pct99, A.Max + B.Max,
A.Sum + B.Sum};
}
/// Vector Difference of Timestats
inline GraphRenderer::TimeStat operator-(const GraphRenderer::TimeStat &A,
const GraphRenderer::TimeStat &B) {
return {A.Count - B.Count, A.Min - B.Min, A.Median - B.Median,
A.Pct90 - B.Pct90, A.Pct99 - B.Pct99, A.Max - B.Max,
A.Sum - B.Sum};
}
/// Scalar Diference of TimeStat and double
inline GraphRenderer::TimeStat operator/(const GraphRenderer::TimeStat &A,
double B) {
return {static_cast<int64_t>(A.Count / B),
A.Min / B,
A.Median / B,
A.Pct90 / B,
A.Pct99 / B,
A.Max / B,
A.Sum / B};
}
/// Scalar product of TimeStat and Double
inline GraphRenderer::TimeStat operator*(const GraphRenderer::TimeStat &A,
double B) {
return {static_cast<int64_t>(A.Count * B),
A.Min * B,
A.Median * B,
A.Pct90 * B,
A.Pct99 * B,
A.Max * B,
A.Sum * B};
}
/// Scalar product of double TimeStat
inline GraphRenderer::TimeStat operator*(double A,
const GraphRenderer::TimeStat &B) {
return B * A;
}
/// Hadamard Product of TimeStats
inline GraphRenderer::TimeStat operator*(const GraphRenderer::TimeStat &A,
const GraphRenderer::TimeStat &B) {
return {A.Count * B.Count, A.Min * B.Min, A.Median * B.Median,
A.Pct90 * B.Pct90, A.Pct99 * B.Pct99, A.Max * B.Max,
A.Sum * B.Sum};
}
/// Hadamard Division of TimeStats
inline GraphRenderer::TimeStat operator/(const GraphRenderer::TimeStat &A,
const GraphRenderer::TimeStat &B) {
return {A.Count / B.Count, A.Min / B.Min, A.Median / B.Median,
A.Pct90 / B.Pct90, A.Pct99 / B.Pct99, A.Max / B.Max,
A.Sum / B.Sum};
}
} // namespace xray
} // namespace llvm
#endif // XRAY_GRAPH_H