CodeGen: Split bundle_iterator into a separate file, NFC

Split MachineBasicBlock::bundle_iterator into a separate file, and
rename the class to MachineBundleIterator.

This is a precursor to adding a `MachineInstr::getBundleIterator()`
accessor, which will eventually let us delete the final call to
getNodePtrUnchecked(), and then remove the UB from ilist_iterator.

As a drive-by, I removed an unnecessary second template parameter.

llvm-svn: 261502

llvm/include/llvm/CodeGen/MachineBasicBlock.h

@@ -15,6 +15,7 @@
 #define LLVM_CODEGEN_MACHINEBASICBLOCK_H
 
 #include "llvm/ADT/GraphTraits.h"
+#include "llvm/CodeGen/MachineInstrBundleIterator.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/Support/BranchProbability.h"
 #include "llvm/MC/MCRegisterInfo.h"
@@ -157,80 +158,14 @@ public:
   const MachineFunction *getParent() const { return xParent; }
   MachineFunction *getParent() { return xParent; }
 
-  /// MachineBasicBlock iterator that automatically skips over MIs that are
-  /// inside bundles (i.e. walk top level MIs only).
-  template<typename Ty, typename IterTy>
-  class bundle_iterator
-    : public std::iterator<std::bidirectional_iterator_tag, Ty, ptrdiff_t> {
-    IterTy MII;
-
-  public:
-    bundle_iterator(IterTy MI) : MII(MI) {}
-
-    bundle_iterator(Ty &MI) : MII(MI) {
-      assert(!MI.isBundledWithPred() &&
-             "It's not legal to initialize bundle_iterator with a bundled MI");
-    }
-    bundle_iterator(Ty *MI) : MII(MI) {
-      assert((!MI || !MI->isBundledWithPred()) &&
-             "It's not legal to initialize bundle_iterator with a bundled MI");
-    }
-    // Template allows conversion from const to nonconst.
-    template<class OtherTy, class OtherIterTy>
-    bundle_iterator(const bundle_iterator<OtherTy, OtherIterTy> &I)
-      : MII(I.getInstrIterator()) {}
-    bundle_iterator() : MII(nullptr) {}
-
-    Ty &operator*() const { return *MII; }
-    Ty *operator->() const { return &operator*(); }
-
-    operator Ty *() const { return MII.getNodePtrUnchecked(); }
-
-    bool operator==(const bundle_iterator &X) const {
-      return MII == X.MII;
-    }
-    bool operator!=(const bundle_iterator &X) const {
-      return !operator==(X);
-    }
-
-    // Increment and decrement operators...
-    bundle_iterator &operator--() {      // predecrement - Back up
-      do --MII;
-      while (MII->isBundledWithPred());
-      return *this;
-    }
-    bundle_iterator &operator++() {      // preincrement - Advance
-      while (MII->isBundledWithSucc())
-        ++MII;
-      ++MII;
-      return *this;
-    }
-    bundle_iterator operator--(int) {    // postdecrement operators...
-      bundle_iterator tmp = *this;
-      --*this;
-      return tmp;
-    }
-    bundle_iterator operator++(int) {    // postincrement operators...
-      bundle_iterator tmp = *this;
-      ++*this;
-      return tmp;
-    }
-
-    IterTy getInstrIterator() const {
-      return MII;
-    }
-  };
-
   typedef Instructions::iterator                                 instr_iterator;
   typedef Instructions::const_iterator                     const_instr_iterator;
   typedef std::reverse_iterator<instr_iterator>          reverse_instr_iterator;
   typedef
   std::reverse_iterator<const_instr_iterator>      const_reverse_instr_iterator;
 
-  typedef
-  bundle_iterator<MachineInstr,instr_iterator>                         iterator;
-  typedef
-  bundle_iterator<const MachineInstr,const_instr_iterator>       const_iterator;
+  typedef MachineInstrBundleIterator<MachineInstr> iterator;
+  typedef MachineInstrBundleIterator<const MachineInstr> const_iterator;
   typedef std::reverse_iterator<const_iterator>          const_reverse_iterator;
   typedef std::reverse_iterator<iterator>                      reverse_iterator;
 

llvm/include/llvm/CodeGen/MachineInstrBundleIterator.h

@@ -0,0 +1,92 @@
+//===- llvm/CodeGen/MachineInstrBundleIterator.h ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines an iterator class that bundles MachineInstr.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_MACHINEINSTRBUNDLEITERATOR_H
+#define LLVM_CODEGEN_MACHINEINSTRBUNDLEITERATOR_H
+
+#include "llvm/ADT/ilist.h"
+#include <iterator>
+
+namespace llvm {
+
+/// MachineBasicBlock iterator that automatically skips over MIs that are
+/// inside bundles (i.e. walk top level MIs only).
+template <typename Ty>
+class MachineInstrBundleIterator
+    : public std::iterator<std::bidirectional_iterator_tag, Ty, ptrdiff_t> {
+  typedef ilist_iterator<Ty> instr_iterator;
+  instr_iterator MII;
+
+public:
+  MachineInstrBundleIterator(instr_iterator MI) : MII(MI) {}
+
+  MachineInstrBundleIterator(Ty &MI) : MII(MI) {
+    assert(!MI.isBundledWithPred() && "It's not legal to initialize "
+                                      "MachineInstrBundleIterator with a "
+                                      "bundled MI");
+  }
+  MachineInstrBundleIterator(Ty *MI) : MII(MI) {
+    // FIXME: This conversion should be explicit.
+    assert((!MI || !MI->isBundledWithPred()) && "It's not legal to initialize "
+                                                "MachineInstrBundleIterator "
+                                                "with a bundled MI");
+  }
+  // Template allows conversion from const to nonconst.
+  template <class OtherTy>
+  MachineInstrBundleIterator(const MachineInstrBundleIterator<OtherTy> &I)
+      : MII(I.getInstrIterator()) {}
+  MachineInstrBundleIterator() : MII(nullptr) {}
+
+  Ty &operator*() const { return *MII; }
+  Ty *operator->() const { return &operator*(); }
+
+  // FIXME: This conversion should be explicit.
+  operator Ty *() const { return MII.getNodePtrUnchecked(); }
+
+  bool operator==(const MachineInstrBundleIterator &X) const {
+    return MII == X.MII;
+  }
+  bool operator!=(const MachineInstrBundleIterator &X) const {
+    return !operator==(X);
+  }
+
+  // Increment and decrement operators...
+  MachineInstrBundleIterator &operator--() {
+    do
+      --MII;
+    while (MII->isBundledWithPred());
+    return *this;
+  }
+  MachineInstrBundleIterator &operator++() {
+    while (MII->isBundledWithSucc())
+      ++MII;
+    ++MII;
+    return *this;
+  }
+  MachineInstrBundleIterator operator--(int) {
+    MachineInstrBundleIterator Temp = *this;
+    --*this;
+    return Temp;
+  }
+  MachineInstrBundleIterator operator++(int) {
+    MachineInstrBundleIterator Temp = *this;
+    ++*this;
+    return Temp;
+  }
+
+  instr_iterator getInstrIterator() const { return MII; }
+};
+
+} // end namespace llvm
+
+#endif