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diff --git a/llvm/lib/CodeGen/RegAllocEvictionAdvisor.cpp b/llvm/lib/CodeGen/RegAllocEvictionAdvisor.cpp
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index 000000000000..9f1012c95964
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+++ b/llvm/lib/CodeGen/RegAllocEvictionAdvisor.cpp
@@ -0,0 +1,121 @@
+//===- RegAllocEvictionAdvisor.cpp - eviction advisor ---------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Implementation of the default eviction advisor and of the Analysis pass.
+//
+//===----------------------------------------------------------------------===//
+
+#include "RegAllocEvictionAdvisor.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/RegisterClassInfo.h"
+#include "llvm/CodeGen/VirtRegMap.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+#include "llvm/PassRegistry.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Target/TargetMachine.h"
+
+using namespace llvm;
+
+static cl::opt<RegAllocEvictionAdvisorAnalysis::AdvisorMode> Mode(
+    "regalloc-enable-advisor", cl::Hidden,
+    cl::init(RegAllocEvictionAdvisorAnalysis::AdvisorMode::Default),
+    cl::desc("Enable regalloc advisor mode"),
+    cl::values(
+        clEnumValN(RegAllocEvictionAdvisorAnalysis::AdvisorMode::Default,
+                   "default", "Default"),
+        clEnumValN(RegAllocEvictionAdvisorAnalysis::AdvisorMode::Release,
+                   "release", "precompiled"),
+        clEnumValN(RegAllocEvictionAdvisorAnalysis::AdvisorMode::Development,
+                   "development", "for training")));
+
+static cl::opt<bool> EnableLocalReassignment(
+    "enable-local-reassign", cl::Hidden,
+    cl::desc("Local reassignment can yield better allocation decisions, but "
+             "may be compile time intensive"),
+    cl::init(false));
+
+#define DEBUG_TYPE "regalloc"
+
+char RegAllocEvictionAdvisorAnalysis::ID = 0;
+INITIALIZE_PASS(RegAllocEvictionAdvisorAnalysis, "regalloc-evict",
+                "Regalloc eviction policy", false, true)
+
+namespace {
+class DefaultEvictionAdvisorAnalysis final
+    : public RegAllocEvictionAdvisorAnalysis {
+public:
+  DefaultEvictionAdvisorAnalysis(bool NotAsRequested)
+      : RegAllocEvictionAdvisorAnalysis(AdvisorMode::Default),
+        NotAsRequested(NotAsRequested) {}
+
+  // support for isa<> and dyn_cast.
+  static bool classof(const RegAllocEvictionAdvisorAnalysis *R) {
+    return R->getAdvisorMode() == AdvisorMode::Default;
+  }
+
+private:
+  std::unique_ptr<RegAllocEvictionAdvisor>
+  getAdvisor(const MachineFunction &MF, LiveRegMatrix *Matrix,
+             LiveIntervals *LIS, VirtRegMap *VRM,
+             const RegisterClassInfo &RegClassInfo,
+             ExtraRegInfo *ExtraInfo) override {
+    return std::make_unique<DefaultEvictionAdvisor>(MF, Matrix, LIS, VRM,
+                                                    RegClassInfo, ExtraInfo);
+  }
+  bool doInitialization(Module &M) override {
+    if (NotAsRequested)
+      M.getContext().emitError("Requested regalloc eviction advisor analysis "
+                               "could be created. Using default");
+    return RegAllocEvictionAdvisorAnalysis::doInitialization(M);
+  }
+  const bool NotAsRequested;
+};
+} // namespace
+
+template <> Pass *llvm::callDefaultCtor<RegAllocEvictionAdvisorAnalysis>() {
+  Pass *Ret = nullptr;
+  switch (Mode) {
+  case RegAllocEvictionAdvisorAnalysis::AdvisorMode::Default:
+    Ret = new DefaultEvictionAdvisorAnalysis(/*NotAsRequested*/ false);
+    break;
+  case RegAllocEvictionAdvisorAnalysis::AdvisorMode::Development:
+    // TODO(mtrofin): add implementation
+    break;
+  case RegAllocEvictionAdvisorAnalysis::AdvisorMode::Release:
+    // TODO(mtrofin): add implementation
+    break;
+  }
+  if (Ret)
+    return Ret;
+  return new DefaultEvictionAdvisorAnalysis(/*NotAsRequested*/ true);
+}
+
+StringRef RegAllocEvictionAdvisorAnalysis::getPassName() const {
+  switch (getAdvisorMode()) {
+  case AdvisorMode::Default:
+    return "Default Regalloc Eviction Advisor";
+  case AdvisorMode::Release:
+    return "Release mode Regalloc Eviction Advisor";
+  case AdvisorMode::Development:
+    return "Development mode Regalloc Eviction Advisor";
+  }
+  llvm_unreachable("Unknown advisor kind");
+}
+
+RegAllocEvictionAdvisor::RegAllocEvictionAdvisor(
+    const MachineFunction &MF, LiveRegMatrix *Matrix, LiveIntervals *LIS,
+    VirtRegMap *VRM, const RegisterClassInfo &RegClassInfo,
+    ExtraRegInfo *ExtraInfo)
+    : MF(MF), Matrix(Matrix), LIS(LIS), VRM(VRM), MRI(&VRM->getRegInfo()),
+      TRI(MF.getSubtarget().getRegisterInfo()), RegClassInfo(RegClassInfo),
+      RegCosts(TRI->getRegisterCosts(MF)), ExtraInfo(ExtraInfo),
+      EnableLocalReassign(EnableLocalReassignment ||
+                          MF.getSubtarget().enableRALocalReassignment(
+                              MF.getTarget().getOptLevel())) {}