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diff --git a/contrib/llvm-project/llvm/lib/Transforms/Utils/GuardUtils.cpp b/contrib/llvm-project/llvm/lib/Transforms/Utils/GuardUtils.cpp
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+++ b/contrib/llvm-project/llvm/lib/Transforms/Utils/GuardUtils.cpp
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+//===-- GuardUtils.cpp - Utils for work with guards -------------*- 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
+//
+//===----------------------------------------------------------------------===//
+// Utils that are used to perform transformations related to guards and their
+// conditions.
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/GuardUtils.h"
+#include "llvm/Analysis/GuardUtils.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/PatternMatch.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+
+using namespace llvm;
+using namespace llvm::PatternMatch;
+
+static cl::opt<uint32_t> PredicatePassBranchWeight(
+    "guards-predicate-pass-branch-weight", cl::Hidden, cl::init(1 << 20),
+    cl::desc("The probability of a guard failing is assumed to be the "
+             "reciprocal of this value (default = 1 << 20)"));
+
+void llvm::makeGuardControlFlowExplicit(Function *DeoptIntrinsic,
+                                        CallInst *Guard, bool UseWC) {
+  OperandBundleDef DeoptOB(*Guard->getOperandBundle(LLVMContext::OB_deopt));
+  SmallVector<Value *, 4> Args(drop_begin(Guard->args()));
+
+  auto *CheckBB = Guard->getParent();
+  auto *DeoptBlockTerm =
+      SplitBlockAndInsertIfThen(Guard->getArgOperand(0), Guard, true);
+
+  auto *CheckBI = cast<BranchInst>(CheckBB->getTerminator());
+
+  // SplitBlockAndInsertIfThen inserts control flow that branches to
+  // DeoptBlockTerm if the condition is true.  We want the opposite.
+  CheckBI->swapSuccessors();
+
+  CheckBI->getSuccessor(0)->setName("guarded");
+  CheckBI->getSuccessor(1)->setName("deopt");
+
+  if (auto *MD = Guard->getMetadata(LLVMContext::MD_make_implicit))
+    CheckBI->setMetadata(LLVMContext::MD_make_implicit, MD);
+
+  MDBuilder MDB(Guard->getContext());
+  CheckBI->setMetadata(LLVMContext::MD_prof,
+                       MDB.createBranchWeights(PredicatePassBranchWeight, 1));
+
+  IRBuilder<> B(DeoptBlockTerm);
+  auto *DeoptCall = B.CreateCall(DeoptIntrinsic, Args, {DeoptOB}, "");
+
+  if (DeoptIntrinsic->getReturnType()->isVoidTy()) {
+    B.CreateRetVoid();
+  } else {
+    DeoptCall->setName("deoptcall");
+    B.CreateRet(DeoptCall);
+  }
+
+  DeoptCall->setCallingConv(Guard->getCallingConv());
+  DeoptBlockTerm->eraseFromParent();
+
+  if (UseWC) {
+    // We want the guard to be expressed as explicit control flow, but still be
+    // widenable. For that, we add Widenable Condition intrinsic call to the
+    // guard's condition.
+    IRBuilder<> B(CheckBI);
+    auto *WC = B.CreateIntrinsic(Intrinsic::experimental_widenable_condition,
+                                 {}, {}, nullptr, "widenable_cond");
+    CheckBI->setCondition(B.CreateAnd(CheckBI->getCondition(), WC,
+                                      "exiplicit_guard_cond"));
+    assert(isWidenableBranch(CheckBI) && "sanity check");
+  }
+}
+
+
+void llvm::widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond) {
+  assert(isWidenableBranch(WidenableBR) && "precondition");
+
+  // The tempting trivially option is to produce something like this:
+  // br (and oldcond, newcond) where oldcond is assumed to contain a widenable
+  // condition, but that doesn't match the pattern parseWidenableBranch expects
+  // so we have to be more sophisticated.
+
+  Use *C, *WC;
+  BasicBlock *IfTrueBB, *IfFalseBB;
+  parseWidenableBranch(WidenableBR, C, WC, IfTrueBB, IfFalseBB);
+  if (!C) {
+    // br (wc()), ... form
+    IRBuilder<> B(WidenableBR);
+    WidenableBR->setCondition(B.CreateAnd(NewCond, WC->get()));
+  } else {
+    // br (wc & C), ... form
+    IRBuilder<> B(WidenableBR);
+    C->set(B.CreateAnd(NewCond, C->get()));
+    Instruction *WCAnd = cast<Instruction>(WidenableBR->getCondition());
+    // Condition is only guaranteed to dominate branch
+    WCAnd->moveBefore(WidenableBR);    
+  }
+  assert(isWidenableBranch(WidenableBR) && "preserve widenabiliy");
+}
+
+void llvm::setWidenableBranchCond(BranchInst *WidenableBR, Value *NewCond) {
+  assert(isWidenableBranch(WidenableBR) && "precondition");
+
+  Use *C, *WC;
+  BasicBlock *IfTrueBB, *IfFalseBB;
+  parseWidenableBranch(WidenableBR, C, WC, IfTrueBB, IfFalseBB);
+  if (!C) {
+    // br (wc()), ... form
+    IRBuilder<> B(WidenableBR);
+    WidenableBR->setCondition(B.CreateAnd(NewCond, WC->get()));
+  } else {
+    // br (wc & C), ... form
+    Instruction *WCAnd = cast<Instruction>(WidenableBR->getCondition());
+    // Condition is only guaranteed to dominate branch
+    WCAnd->moveBefore(WidenableBR);
+    C->set(NewCond);
+  }
+  assert(isWidenableBranch(WidenableBR) && "preserve widenabiliy");
+}