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diff --git a/tools/llvm-xray/xray-color-helper.h b/tools/llvm-xray/xray-color-helper.h
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+++ b/tools/llvm-xray/xray-color-helper.h
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+//===-- xray-graph.h - XRay Function Call Graph Renderer --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// A class to get a color from a specified gradient.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef XRAY_COLOR_HELPER_H
+#define XRAY_COLOR_HELPER_H
+
+#include <tuple>
+
+#include "llvm/ADT/ArrayRef.h"
+
+namespace llvm {
+namespace xray {
+
+/// The color helper class it a healper class which allows you to easily get a
+/// color in a gradient. This is used to color-code edges in XRay-Graph tools.
+///
+/// There are two types of color schemes in this class:
+///   - Sequential schemes, which are used to represent information from some
+///     minimum to some maximum. These take an input in the range [0,1]
+///   - Diverging schemes, which are used to represent information representing
+///     differenes, or a range that goes from negative to positive. These take
+///     an input in the range [-1,1].
+/// Usage;
+/// ColorHelper S(ColorHelper::SequentialScheme::OrRd); //Chose a color scheme.
+/// for (double p = 0.0; p <= 1; p += 0.1){
+///   cout() << S.getColor(p) << " \n"; // Sample the gradient at 0.1 intervals
+/// }
+///
+/// ColorHelper D(ColorHelper::DivergingScheme::Spectral); // Choose a color
+///                                                        // scheme.
+/// for (double p= -1; p <= 1 ; p += 0.1){
+///   cout() << D.getColor(p) << " \n"; // sample the gradient at 0.1 intervals
+/// }
+class ColorHelper {
+  double MinIn;
+  double MaxIn;
+
+  ArrayRef<std::tuple<uint8_t, uint8_t, uint8_t>> ColorMap;
+
+public:
+  /// Enum of the availible Sequential Color Schemes
+  enum class SequentialScheme {
+    // Schemes based on the ColorBrewer Color schemes of the same name from
+    // http://www.colorbrewer.org/ by Cynthis A Brewer Penn State University.
+    Greys,
+    OrRd,
+    PuBu
+  };
+
+  ColorHelper(SequentialScheme S);
+
+  /// Enum of the availible Diverging Color Schemes
+  enum class DivergingScheme {
+    // Schemes based on the ColorBrewer Color schemes of the same name from
+    // http://www.colorbrewer.org/ by Cynthis A Brewer Penn State University.
+    PiYG
+  };
+
+  ColorHelper(DivergingScheme S);
+
+  // Sample the gradient at the input point.
+  std::tuple<uint8_t, uint8_t, uint8_t> getColorTuple(double Point) const;
+
+  std::string getColorString(double Point) const;
+
+  // Convert a tuple to a string
+  static std::string getColorString(std::tuple<uint8_t, uint8_t, uint8_t> t);
+};
+}
+}
+#endif