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diff --git a/contrib/llvm-project/llvm/lib/Target/MSP430/MSP430BranchSelector.cpp b/contrib/llvm-project/llvm/lib/Target/MSP430/MSP430BranchSelector.cpp
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index 000000000000..45e7c26e4d30
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+++ b/contrib/llvm-project/llvm/lib/Target/MSP430/MSP430BranchSelector.cpp
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+//===-- MSP430BranchSelector.cpp - Emit long conditional branches ---------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a pass that scans a machine function to determine which
+// conditional branches need more than 10 bits of displacement to reach their
+// target basic block.  It does this in two passes; a calculation of basic block
+// positions pass, and a branch pseudo op to machine branch opcode pass.  This
+// pass should be run last, just before the assembly printer.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MSP430.h"
+#include "MSP430InstrInfo.h"
+#include "MSP430Subtarget.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Target/TargetMachine.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "msp430-branch-select"
+
+static cl::opt<bool>
+    BranchSelectEnabled("msp430-branch-select", cl::Hidden, cl::init(true),
+                        cl::desc("Expand out of range branches"));
+
+STATISTIC(NumSplit, "Number of machine basic blocks split");
+STATISTIC(NumExpanded, "Number of branches expanded to long format");
+
+namespace {
+class MSP430BSel : public MachineFunctionPass {
+
+  typedef SmallVector<int, 16> OffsetVector;
+
+  MachineFunction *MF;
+  const MSP430InstrInfo *TII;
+
+  unsigned measureFunction(OffsetVector &BlockOffsets,
+                           MachineBasicBlock *FromBB = nullptr);
+  bool expandBranches(OffsetVector &BlockOffsets);
+
+public:
+  static char ID;
+  MSP430BSel() : MachineFunctionPass(ID) {}
+
+  bool runOnMachineFunction(MachineFunction &MF) override;
+
+  MachineFunctionProperties getRequiredProperties() const override {
+    return MachineFunctionProperties().set(
+        MachineFunctionProperties::Property::NoVRegs);
+  }
+
+  StringRef getPassName() const override { return "MSP430 Branch Selector"; }
+};
+char MSP430BSel::ID = 0;
+}
+
+static bool isInRage(int DistanceInBytes) {
+  // According to CC430 Family User's Guide, Section 4.5.1.3, branch
+  // instructions have the signed 10-bit word offset field, so first we need to
+  // convert the distance from bytes to words, then check if it fits in 10-bit
+  // signed integer.
+  const int WordSize = 2;
+
+  assert((DistanceInBytes % WordSize == 0) &&
+         "Branch offset should be word aligned!");
+
+  int Words = DistanceInBytes / WordSize;
+  return isInt<10>(Words);
+}
+
+/// Measure each basic block, fill the BlockOffsets, and return the size of
+/// the function, starting with BB
+unsigned MSP430BSel::measureFunction(OffsetVector &BlockOffsets,
+                                     MachineBasicBlock *FromBB) {
+  // Give the blocks of the function a dense, in-order, numbering.
+  MF->RenumberBlocks(FromBB);
+
+  MachineFunction::iterator Begin;
+  if (FromBB == nullptr) {
+    Begin = MF->begin();
+  } else {
+    Begin = FromBB->getIterator();
+  }
+
+  BlockOffsets.resize(MF->getNumBlockIDs());
+
+  unsigned TotalSize = BlockOffsets[Begin->getNumber()];
+  for (auto &MBB : make_range(Begin, MF->end())) {
+    BlockOffsets[MBB.getNumber()] = TotalSize;
+    for (MachineInstr &MI : MBB) {
+      TotalSize += TII->getInstSizeInBytes(MI);
+    }
+  }
+  return TotalSize;
+}
+
+/// Do expand branches and split the basic blocks if necessary.
+/// Returns true if made any change.
+bool MSP430BSel::expandBranches(OffsetVector &BlockOffsets) {
+  // For each conditional branch, if the offset to its destination is larger
+  // than the offset field allows, transform it into a long branch sequence
+  // like this:
+  //   short branch:
+  //     bCC MBB
+  //   long branch:
+  //     b!CC $PC+6
+  //     b MBB
+  //
+  bool MadeChange = false;
+  for (auto MBB = MF->begin(), E = MF->end(); MBB != E; ++MBB) {
+    unsigned MBBStartOffset = 0;
+    for (auto MI = MBB->begin(), EE = MBB->end(); MI != EE; ++MI) {
+      MBBStartOffset += TII->getInstSizeInBytes(*MI);
+
+      // If this instruction is not a short branch then skip it.
+      if (MI->getOpcode() != MSP430::JCC && MI->getOpcode() != MSP430::JMP) {
+        continue;
+      }
+
+      MachineBasicBlock *DestBB = MI->getOperand(0).getMBB();
+      // Determine the distance from the current branch to the destination
+      // block. MBBStartOffset already includes the size of the current branch
+      // instruction.
+      int BlockDistance =
+          BlockOffsets[DestBB->getNumber()] - BlockOffsets[MBB->getNumber()];
+      int BranchDistance = BlockDistance - MBBStartOffset;
+
+      // If this branch is in range, ignore it.
+      if (isInRage(BranchDistance)) {
+        continue;
+      }
+
+      LLVM_DEBUG(dbgs() << "  Found a branch that needs expanding, "
+                        << printMBBReference(*DestBB) << ", Distance "
+                        << BranchDistance << "\n");
+
+      // If JCC is not the last instruction we need to split the MBB.
+      if (MI->getOpcode() == MSP430::JCC && std::next(MI) != EE) {
+
+        LLVM_DEBUG(dbgs() << "  Found a basic block that needs to be split, "
+                          << printMBBReference(*MBB) << "\n");
+
+        // Create a new basic block.
+        MachineBasicBlock *NewBB =
+            MF->CreateMachineBasicBlock(MBB->getBasicBlock());
+        MF->insert(std::next(MBB), NewBB);
+
+        // Splice the instructions following MI over to the NewBB.
+        NewBB->splice(NewBB->end(), &*MBB, std::next(MI), MBB->end());
+
+        // Update the successor lists.
+        for (MachineBasicBlock *Succ : MBB->successors()) {
+          if (Succ == DestBB) {
+            continue;
+          }
+          MBB->replaceSuccessor(Succ, NewBB);
+          NewBB->addSuccessor(Succ);
+        }
+
+        // We introduced a new MBB so all following blocks should be numbered
+        // and measured again.
+        measureFunction(BlockOffsets, &*MBB);
+
+        ++NumSplit;
+
+        // It may be not necessary to start all over at this point, but it's
+        // safer do this anyway.
+        return true;
+      }
+
+      MachineInstr &OldBranch = *MI;
+      DebugLoc dl = OldBranch.getDebugLoc();
+      int InstrSizeDiff = -TII->getInstSizeInBytes(OldBranch);
+
+      if (MI->getOpcode() == MSP430::JCC) {
+        MachineBasicBlock *NextMBB = &*std::next(MBB);
+        assert(MBB->isSuccessor(NextMBB) &&
+               "This block must have a layout successor!");
+
+        // The BCC operands are:
+        // 0. Target MBB
+        // 1. MSP430 branch predicate
+        SmallVector<MachineOperand, 1> Cond;
+        Cond.push_back(MI->getOperand(1));
+
+        // Jump over the long branch on the opposite condition
+        TII->reverseBranchCondition(Cond);
+        MI = BuildMI(*MBB, MI, dl, TII->get(MSP430::JCC))
+                 .addMBB(NextMBB)
+                 .add(Cond[0]);
+        InstrSizeDiff += TII->getInstSizeInBytes(*MI);
+        ++MI;
+      }
+
+      // Unconditional branch to the real destination.
+      MI = BuildMI(*MBB, MI, dl, TII->get(MSP430::Bi)).addMBB(DestBB);
+      InstrSizeDiff += TII->getInstSizeInBytes(*MI);
+
+      // Remove the old branch from the function.
+      OldBranch.eraseFromParent();
+
+      // The size of a new instruction is different from the old one, so we need
+      // to correct all block offsets.
+      for (int i = MBB->getNumber() + 1, e = BlockOffsets.size(); i < e; ++i) {
+        BlockOffsets[i] += InstrSizeDiff;
+      }
+      MBBStartOffset += InstrSizeDiff;
+
+      ++NumExpanded;
+      MadeChange = true;
+    }
+  }
+  return MadeChange;
+}
+
+bool MSP430BSel::runOnMachineFunction(MachineFunction &mf) {
+  MF = &mf;
+  TII = static_cast<const MSP430InstrInfo *>(MF->getSubtarget().getInstrInfo());
+
+  // If the pass is disabled, just bail early.
+  if (!BranchSelectEnabled)
+    return false;
+
+  LLVM_DEBUG(dbgs() << "\n********** " << getPassName() << " **********\n");
+
+  // BlockOffsets - Contains the distance from the beginning of the function to
+  // the beginning of each basic block.
+  OffsetVector BlockOffsets;
+
+  unsigned FunctionSize = measureFunction(BlockOffsets);
+  // If the entire function is smaller than the displacement of a branch field,
+  // we know we don't need to expand any branches in this
+  // function. This is a common case.
+  if (isInRage(FunctionSize)) {
+    return false;
+  }
+
+  // Iteratively expand branches until we reach a fixed point.
+  bool MadeChange = false;
+  while (expandBranches(BlockOffsets))
+    MadeChange = true;
+
+  return MadeChange;
+}
+
+/// Returns an instance of the Branch Selection Pass
+FunctionPass *llvm::createMSP430BranchSelectionPass() {
+  return new MSP430BSel();
+}