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diff --git a/contrib/llvm-project/llvm/lib/Transforms/IPO/StripSymbols.cpp b/contrib/llvm-project/llvm/lib/Transforms/IPO/StripSymbols.cpp
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index 000000000000..9d4e9464f361
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+++ b/contrib/llvm-project/llvm/lib/Transforms/IPO/StripSymbols.cpp
@@ -0,0 +1,415 @@
+//===- StripSymbols.cpp - Strip symbols and debug info from a module ------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// The StripSymbols transformation implements code stripping. Specifically, it
+// can delete:
+//
+//   * names for virtual registers
+//   * symbols for internal globals and functions
+//   * debug information
+//
+// Note that this transformation makes code much less readable, so it should
+// only be used in situations where the 'strip' utility would be used, such as
+// reducing code size or making it harder to reverse engineer code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/IPO/StripSymbols.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/IR/TypeFinder.h"
+#include "llvm/IR/ValueSymbolTable.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/Utils/Local.h"
+
+using namespace llvm;
+
+namespace {
+  class StripSymbols : public ModulePass {
+    bool OnlyDebugInfo;
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripSymbols(bool ODI = false)
+      : ModulePass(ID), OnlyDebugInfo(ODI) {
+        initializeStripSymbolsPass(*PassRegistry::getPassRegistry());
+      }
+
+    bool runOnModule(Module &M) override;
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+  };
+
+  class StripNonDebugSymbols : public ModulePass {
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripNonDebugSymbols()
+      : ModulePass(ID) {
+        initializeStripNonDebugSymbolsPass(*PassRegistry::getPassRegistry());
+      }
+
+    bool runOnModule(Module &M) override;
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+  };
+
+  class StripDebugDeclare : public ModulePass {
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripDebugDeclare()
+      : ModulePass(ID) {
+        initializeStripDebugDeclarePass(*PassRegistry::getPassRegistry());
+      }
+
+    bool runOnModule(Module &M) override;
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+  };
+
+  class StripDeadDebugInfo : public ModulePass {
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripDeadDebugInfo()
+      : ModulePass(ID) {
+        initializeStripDeadDebugInfoPass(*PassRegistry::getPassRegistry());
+      }
+
+    bool runOnModule(Module &M) override;
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesAll();
+    }
+  };
+}
+
+char StripSymbols::ID = 0;
+INITIALIZE_PASS(StripSymbols, "strip",
+                "Strip all symbols from a module", false, false)
+
+ModulePass *llvm::createStripSymbolsPass(bool OnlyDebugInfo) {
+  return new StripSymbols(OnlyDebugInfo);
+}
+
+char StripNonDebugSymbols::ID = 0;
+INITIALIZE_PASS(StripNonDebugSymbols, "strip-nondebug",
+                "Strip all symbols, except dbg symbols, from a module",
+                false, false)
+
+ModulePass *llvm::createStripNonDebugSymbolsPass() {
+  return new StripNonDebugSymbols();
+}
+
+char StripDebugDeclare::ID = 0;
+INITIALIZE_PASS(StripDebugDeclare, "strip-debug-declare",
+                "Strip all llvm.dbg.declare intrinsics", false, false)
+
+ModulePass *llvm::createStripDebugDeclarePass() {
+  return new StripDebugDeclare();
+}
+
+char StripDeadDebugInfo::ID = 0;
+INITIALIZE_PASS(StripDeadDebugInfo, "strip-dead-debug-info",
+                "Strip debug info for unused symbols", false, false)
+
+ModulePass *llvm::createStripDeadDebugInfoPass() {
+  return new StripDeadDebugInfo();
+}
+
+/// OnlyUsedBy - Return true if V is only used by Usr.
+static bool OnlyUsedBy(Value *V, Value *Usr) {
+  for (User *U : V->users())
+    if (U != Usr)
+      return false;
+
+  return true;
+}
+
+static void RemoveDeadConstant(Constant *C) {
+  assert(C->use_empty() && "Constant is not dead!");
+  SmallPtrSet<Constant*, 4> Operands;
+  for (Value *Op : C->operands())
+    if (OnlyUsedBy(Op, C))
+      Operands.insert(cast<Constant>(Op));
+  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
+    if (!GV->hasLocalLinkage()) return;   // Don't delete non-static globals.
+    GV->eraseFromParent();
+  } else if (!isa<Function>(C)) {
+    // FIXME: Why does the type of the constant matter here?
+    if (isa<StructType>(C->getType()) || isa<ArrayType>(C->getType()) ||
+        isa<VectorType>(C->getType()))
+      C->destroyConstant();
+  }
+
+  // If the constant referenced anything, see if we can delete it as well.
+  for (Constant *O : Operands)
+    RemoveDeadConstant(O);
+}
+
+// Strip the symbol table of its names.
+//
+static void StripSymtab(ValueSymbolTable &ST, bool PreserveDbgInfo) {
+  for (ValueSymbolTable::iterator VI = ST.begin(), VE = ST.end(); VI != VE; ) {
+    Value *V = VI->getValue();
+    ++VI;
+    if (!isa<GlobalValue>(V) || cast<GlobalValue>(V)->hasLocalLinkage()) {
+      if (!PreserveDbgInfo || !V->getName().startswith("llvm.dbg"))
+        // Set name to "", removing from symbol table!
+        V->setName("");
+    }
+  }
+}
+
+// Strip any named types of their names.
+static void StripTypeNames(Module &M, bool PreserveDbgInfo) {
+  TypeFinder StructTypes;
+  StructTypes.run(M, false);
+
+  for (unsigned i = 0, e = StructTypes.size(); i != e; ++i) {
+    StructType *STy = StructTypes[i];
+    if (STy->isLiteral() || STy->getName().empty()) continue;
+
+    if (PreserveDbgInfo && STy->getName().startswith("llvm.dbg"))
+      continue;
+
+    STy->setName("");
+  }
+}
+
+/// Find values that are marked as llvm.used.
+static void findUsedValues(GlobalVariable *LLVMUsed,
+                           SmallPtrSetImpl<const GlobalValue*> &UsedValues) {
+  if (!LLVMUsed) return;
+  UsedValues.insert(LLVMUsed);
+
+  ConstantArray *Inits = cast<ConstantArray>(LLVMUsed->getInitializer());
+
+  for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i)
+    if (GlobalValue *GV =
+          dyn_cast<GlobalValue>(Inits->getOperand(i)->stripPointerCasts()))
+      UsedValues.insert(GV);
+}
+
+/// StripSymbolNames - Strip symbol names.
+static bool StripSymbolNames(Module &M, bool PreserveDbgInfo) {
+
+  SmallPtrSet<const GlobalValue*, 8> llvmUsedValues;
+  findUsedValues(M.getGlobalVariable("llvm.used"), llvmUsedValues);
+  findUsedValues(M.getGlobalVariable("llvm.compiler.used"), llvmUsedValues);
+
+  for (GlobalVariable &GV : M.globals()) {
+    if (GV.hasLocalLinkage() && !llvmUsedValues.contains(&GV))
+      if (!PreserveDbgInfo || !GV.getName().startswith("llvm.dbg"))
+        GV.setName(""); // Internal symbols can't participate in linkage
+  }
+
+  for (Function &I : M) {
+    if (I.hasLocalLinkage() && !llvmUsedValues.contains(&I))
+      if (!PreserveDbgInfo || !I.getName().startswith("llvm.dbg"))
+        I.setName(""); // Internal symbols can't participate in linkage
+    if (auto *Symtab = I.getValueSymbolTable())
+      StripSymtab(*Symtab, PreserveDbgInfo);
+  }
+
+  // Remove all names from types.
+  StripTypeNames(M, PreserveDbgInfo);
+
+  return true;
+}
+
+bool StripSymbols::runOnModule(Module &M) {
+  if (skipModule(M))
+    return false;
+
+  bool Changed = false;
+  Changed |= StripDebugInfo(M);
+  if (!OnlyDebugInfo)
+    Changed |= StripSymbolNames(M, false);
+  return Changed;
+}
+
+bool StripNonDebugSymbols::runOnModule(Module &M) {
+  if (skipModule(M))
+    return false;
+
+  return StripSymbolNames(M, true);
+}
+
+static bool stripDebugDeclareImpl(Module &M) {
+
+  Function *Declare = M.getFunction("llvm.dbg.declare");
+  std::vector<Constant*> DeadConstants;
+
+  if (Declare) {
+    while (!Declare->use_empty()) {
+      CallInst *CI = cast<CallInst>(Declare->user_back());
+      Value *Arg1 = CI->getArgOperand(0);
+      Value *Arg2 = CI->getArgOperand(1);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg1->use_empty()) {
+        if (Constant *C = dyn_cast<Constant>(Arg1))
+          DeadConstants.push_back(C);
+        else
+          RecursivelyDeleteTriviallyDeadInstructions(Arg1);
+      }
+      if (Arg2->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg2))
+          DeadConstants.push_back(C);
+    }
+    Declare->eraseFromParent();
+  }
+
+  while (!DeadConstants.empty()) {
+    Constant *C = DeadConstants.back();
+    DeadConstants.pop_back();
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
+      if (GV->hasLocalLinkage())
+        RemoveDeadConstant(GV);
+    } else
+      RemoveDeadConstant(C);
+  }
+
+  return true;
+}
+
+bool StripDebugDeclare::runOnModule(Module &M) {
+  if (skipModule(M))
+    return false;
+  return stripDebugDeclareImpl(M);
+}
+
+static bool stripDeadDebugInfoImpl(Module &M) {
+  bool Changed = false;
+
+  LLVMContext &C = M.getContext();
+
+  // Find all debug info in F. This is actually overkill in terms of what we
+  // want to do, but we want to try and be as resilient as possible in the face
+  // of potential debug info changes by using the formal interfaces given to us
+  // as much as possible.
+  DebugInfoFinder F;
+  F.processModule(M);
+
+  // For each compile unit, find the live set of global variables/functions and
+  // replace the current list of potentially dead global variables/functions
+  // with the live list.
+  SmallVector<Metadata *, 64> LiveGlobalVariables;
+  DenseSet<DIGlobalVariableExpression *> VisitedSet;
+
+  std::set<DIGlobalVariableExpression *> LiveGVs;
+  for (GlobalVariable &GV : M.globals()) {
+    SmallVector<DIGlobalVariableExpression *, 1> GVEs;
+    GV.getDebugInfo(GVEs);
+    for (auto *GVE : GVEs)
+      LiveGVs.insert(GVE);
+  }
+
+  std::set<DICompileUnit *> LiveCUs;
+  // Any CU referenced from a subprogram is live.
+  for (DISubprogram *SP : F.subprograms()) {
+    if (SP->getUnit())
+      LiveCUs.insert(SP->getUnit());
+  }
+
+  bool HasDeadCUs = false;
+  for (DICompileUnit *DIC : F.compile_units()) {
+    // Create our live global variable list.
+    bool GlobalVariableChange = false;
+    for (auto *DIG : DIC->getGlobalVariables()) {
+      if (DIG->getExpression() && DIG->getExpression()->isConstant())
+        LiveGVs.insert(DIG);
+
+      // Make sure we only visit each global variable only once.
+      if (!VisitedSet.insert(DIG).second)
+        continue;
+
+      // If a global variable references DIG, the global variable is live.
+      if (LiveGVs.count(DIG))
+        LiveGlobalVariables.push_back(DIG);
+      else
+        GlobalVariableChange = true;
+    }
+
+    if (!LiveGlobalVariables.empty())
+      LiveCUs.insert(DIC);
+    else if (!LiveCUs.count(DIC))
+      HasDeadCUs = true;
+
+    // If we found dead global variables, replace the current global
+    // variable list with our new live global variable list.
+    if (GlobalVariableChange) {
+      DIC->replaceGlobalVariables(MDTuple::get(C, LiveGlobalVariables));
+      Changed = true;
+    }
+
+    // Reset lists for the next iteration.
+    LiveGlobalVariables.clear();
+  }
+
+  if (HasDeadCUs) {
+    // Delete the old node and replace it with a new one
+    NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
+    NMD->clearOperands();
+    if (!LiveCUs.empty()) {
+      for (DICompileUnit *CU : LiveCUs)
+        NMD->addOperand(CU);
+    }
+    Changed = true;
+  }
+
+  return Changed;
+}
+
+/// Remove any debug info for global variables/functions in the given module for
+/// which said global variable/function no longer exists (i.e. is null).
+///
+/// Debugging information is encoded in llvm IR using metadata. This is designed
+/// such a way that debug info for symbols preserved even if symbols are
+/// optimized away by the optimizer. This special pass removes debug info for
+/// such symbols.
+bool StripDeadDebugInfo::runOnModule(Module &M) {
+  if (skipModule(M))
+    return false;
+  return stripDeadDebugInfoImpl(M);
+}
+
+PreservedAnalyses StripSymbolsPass::run(Module &M, ModuleAnalysisManager &AM) {
+  StripDebugInfo(M);
+  StripSymbolNames(M, false);
+  return PreservedAnalyses::all();
+}
+
+PreservedAnalyses StripNonDebugSymbolsPass::run(Module &M,
+                                                ModuleAnalysisManager &AM) {
+  StripSymbolNames(M, true);
+  return PreservedAnalyses::all();
+}
+
+PreservedAnalyses StripDebugDeclarePass::run(Module &M,
+                                             ModuleAnalysisManager &AM) {
+  stripDebugDeclareImpl(M);
+  return PreservedAnalyses::all();
+}
+
+PreservedAnalyses StripDeadDebugInfoPass::run(Module &M,
+                                              ModuleAnalysisManager &AM) {
+  stripDeadDebugInfoImpl(M);
+  return PreservedAnalyses::all();
+}