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diff --git a/src/tuning/xgemm.cc b/src/tuning/xgemm.cc
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+
+// =================================================================================================
+// This file is part of the CLBlast project. The project is licensed under Apache Version 2.0. This
+// project loosely follows the Google C++ styleguide and uses a tab-size of two spaces and a max-
+// width of 100 characters per line.
+//
+// Author(s):
+//   Cedric Nugteren <www.cedricnugteren.nl>
+//
+// This file implements an auto-tuner to tune the Xgemm OpenCL kernel. It uses the CLTune library.
+// Note that this tuner uses random-search: running it multiple times or with a larger fraction
+// argument might be neccessary to obtain good results.
+//
+// =================================================================================================
+
+#include <string>
+#include <vector>
+#include <stdexcept>
+
+#include "internal/utilities.h"
+#include "internal/tuning.h"
+
+namespace clblast {
+// =================================================================================================
+
+// The Xgemm auto-tuner
+template <typename T>
+void XgemmTune(const Arguments<T> &args,
+               const std::vector<T> &a_mat, const std::vector<T> &b_mat, std::vector<T> &c_mat,
+               cltune::Tuner &tuner) {
+
+  // This points to the Xgemm kernel as found in the CLBlast library and its golden reference
+  std::string common_source =
+  #include "../src/kernels/common.opencl"
+  std::string kernel_source =
+  #include "../src/kernels/xgemm.opencl"
+  auto sources = common_source + kernel_source;
+  auto id = tuner.AddKernelFromString(sources, "Xgemm", {args.m, args.n}, {1, 1});
+  tuner.SetReferenceFromString(sources, "Xgemm", {args.m, args.n}, {8, 8});
+
+  // Sets the tunable parameters and their possible values
+  tuner.AddParameter(id, "MWG", {16, 32, 64, 128});
+  tuner.AddParameter(id, "NWG", {16, 32, 64, 128});
+  tuner.AddParameter(id, "KWG", {16, 32});
+  tuner.AddParameter(id, "MDIMC", {8, 16, 32});
+  tuner.AddParameter(id, "NDIMC", {8, 16, 32});
+  tuner.AddParameter(id, "MDIMA", {8, 16, 32});
+  tuner.AddParameter(id, "NDIMB", {8, 16, 32});
+  tuner.AddParameter(id, "KWI", {2, 8});
+  tuner.AddParameter(id, "VWM", {1, 2, 4, 8});
+  tuner.AddParameter(id, "VWN", {1, 2, 4, 8});
+  tuner.AddParameter(id, "STRM", {0, 1});
+  tuner.AddParameter(id, "STRN", {0, 1});
+  tuner.AddParameter(id, "SA", {0, 1});
+  tuner.AddParameter(id, "SB", {0, 1});
+
+  // Tests for a specific precision
+  tuner.AddParameter(id, "PRECISION", {static_cast<size_t>(args.precision)});
+  tuner.AddParameterReference("PRECISION", static_cast<size_t>(args.precision));
+
+  // Sets the helper functions to implement the constraints below
+  auto MultipleOfX = [] (std::vector<size_t> v) { return IsMultiple(v[0], v[1]); };
+  auto MultipleOfXMulY = [] (std::vector<size_t> v) { return IsMultiple(v[0], v[1]*v[2]); };
+  auto MultipleOfXMulYDivZ = [] (std::vector<size_t> v) { return IsMultiple(v[0], (v[1]*v[2])/v[3]); };
+
+  // Sets constraints: Requirement for unrolling the KWG loop
+  tuner.AddConstraint(id, MultipleOfX, {"KWG", "KWI"});
+
+  // Sets constraints: Required for integer MWI and NWI
+  tuner.AddConstraint(id, MultipleOfXMulY, {"MWG", "MDIMC", "VWM"});
+  tuner.AddConstraint(id, MultipleOfXMulY, {"NWG", "NDIMC", "VWN"});
+
+  // Sets constraints: Required for integer MWIA and NWIB
+  tuner.AddConstraint(id, MultipleOfXMulY, {"MWG", "MDIMA", "VWM"});
+  tuner.AddConstraint(id, MultipleOfXMulY, {"NWG", "NDIMB", "VWN"});
+
+  // Sets constraints: KWG has to be a multiple of KDIMA = ((MDIMC*NDIMC)/(MDIMA)) and KDIMB = (...)
+  tuner.AddConstraint(id, MultipleOfXMulYDivZ, {"KWG", "MDIMC", "NDIMC", "MDIMA"});
+  tuner.AddConstraint(id, MultipleOfXMulYDivZ, {"KWG", "MDIMC", "NDIMC", "NDIMB"});
+
+  // Sets the constraints for local memory size limitations
+  auto LocalMemorySize = [args] (std::vector<size_t> v) {
+    return (((v[0]*v[1]*v[2]/v[3]) + (v[4]*v[5]*v[6]/v[7]))*GetBytes(args.precision));
+  };
+  tuner.SetLocalMemoryUsage(id, LocalMemorySize, {"SA", "KWG", "MWG", "VWM",
+                                                  "SB", "KWG", "NWG", "VWN"});
+
+  // Modifies the thread-sizes (both global and local) based on the parameters
+  tuner.MulLocalSize(id, {"MDIMC", "NDIMC"});
+  tuner.MulGlobalSize(id, {"MDIMC", "NDIMC"});
+  tuner.DivGlobalSize(id, {"MWG", "NWG"});
+
+  // Sets the function's arguments
+  tuner.AddArgumentScalar(static_cast<int>(args.m));
+  tuner.AddArgumentScalar(static_cast<int>(args.n));
+  tuner.AddArgumentScalar(static_cast<int>(args.k));
+  tuner.AddArgumentScalar(args.alpha);
+  tuner.AddArgumentScalar(args.beta);
+  tuner.AddArgumentInput(a_mat);
+  tuner.AddArgumentInput(b_mat);
+  tuner.AddArgumentOutput(c_mat);
+}
+
+// =================================================================================================
+
+// Main function which calls the common client code with the routine-specific function as argument.
+void TunerXgemm(int argc, char *argv[]) {
+  switch(GetPrecision(argc, argv)) {
+    case Precision::kHalf: throw std::runtime_error("Unsupported precision mode");
+    case Precision::kSingle: TunerABC<float>(argc, argv, XgemmTune<float>); break;
+    case Precision::kDouble: TunerABC<double>(argc, argv, XgemmTune<double>); break;
+    case Precision::kComplexSingle: TunerABC<float2>(argc, argv, XgemmTune<float2>); break;
+    case Precision::kComplexDouble: TunerABC<double2>(argc, argv, XgemmTune<double2>); break;
+  }
+}
+
+// =================================================================================================
+} // namespace clblast
+
+// Main function (not within the clblast namespace)
+int main(int argc, char *argv[]) {
+  clblast::TunerXgemm(argc, argv);
+  return 0;
+}
+
+// =================================================================================================