Tighten up the splice() API for bundled instructions.

Remove the instr_iterator versions of the splice() functions. It doesn't
seem useful to be able to splice sequences of instructions that don't
consist of full bundles.

The normal splice functions that take MBB::iterator arguments are not
changed, and they can move whole bundles around without any problems.

llvm-svn: 170456

llvm/include/llvm/CodeGen/MachineBasicBlock.h

@@ -524,23 +524,24 @@ public:
     Insts.clear();
   }
 
-  /// splice - Take an instruction from MBB 'Other' at the position From,
-  /// and insert it into this MBB right before 'where'.
-  void splice(instr_iterator where, MachineBasicBlock *Other,
-              instr_iterator From) {
-    Insts.splice(where, Other->Insts, From);
+  /// Take an instruction from MBB 'Other' at the position From, and insert it
+  /// into this MBB right before 'Where'.
+  ///
+  /// If From points to a bundle of instructions, the whole bundle is moved.
+  void splice(iterator Where, MachineBasicBlock *Other, iterator From) {
+    // The range splice() doesn't allow noop moves, but this one does.
+    if (Where != From)
+      splice(Where, Other, From, llvm::next(From));
   }
-  void splice(iterator where, MachineBasicBlock *Other, iterator From);
 
-  /// splice - Take a block of instructions from MBB 'Other' in the range [From,
-  /// To), and insert them into this MBB right before 'where'.
-  void splice(instr_iterator where, MachineBasicBlock *Other, instr_iterator From,
-              instr_iterator To) {
-    Insts.splice(where, Other->Insts, From, To);
-  }
-  void splice(iterator where, MachineBasicBlock *Other, iterator From,
-              iterator To) {
-    Insts.splice(where.getInstrIterator(), Other->Insts,
+  /// Take a block of instructions from MBB 'Other' in the range [From, To),
+  /// and insert them into this MBB right before 'Where'.
+  ///
+  /// The instruction at 'Where' must not be included in the range of
+  /// instructions to move.
+  void splice(iterator Where, MachineBasicBlock *Other,
+              iterator From, iterator To) {
+    Insts.splice(Where.getInstrIterator(), Other->Insts,
                  From.getInstrIterator(), To.getInstrIterator());
   }
 

llvm/lib/CodeGen/MachineBasicBlock.cpp

@@ -826,19 +826,6 @@ MachineBasicBlock::insert(instr_iterator I, MachineInstr *MI) {
   return Insts.insert(I, MI);
 }
 
-void MachineBasicBlock::splice(MachineBasicBlock::iterator where,
-                               MachineBasicBlock *Other,
-                               MachineBasicBlock::iterator From) {
-  if (From->isBundle()) {
-    MachineBasicBlock::iterator To = llvm::next(From);
-    Insts.splice(where.getInstrIterator(), Other->Insts,
-                 From.getInstrIterator(), To.getInstrIterator());
-    return;
-  }
-
-  Insts.splice(where.getInstrIterator(), Other->Insts, From.getInstrIterator());
-}
-
 /// removeFromParent - This method unlinks 'this' from the containing function,
 /// and returns it, but does not delete it.
 MachineBasicBlock *MachineBasicBlock::removeFromParent() {