- Add "Bitcast" target instruction property for instructions which perform

nothing more than a bitcast.
- Teach tablegen to automatically infer "Bitcast" property.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127667 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/Target.td

@@ -200,6 +200,7 @@ class Instruction {
   bit isIndirectBranch = 0; // Is this instruction an indirect branch?
   bit isCompare    = 0;     // Is this instruction a comparison instruction?
   bit isMoveImm    = 0;     // Is this instruction a move immediate instruction?
+  bit isBitcast    = 0;     // Is this instruction a bitcast instruction?
   bit isBarrier    = 0;     // Can control flow fall through this instruction?
   bit isCall       = 0;     // Is this instruction a call instruction?
   bit canFoldAsLoad = 0;    // Can this be folded as a simple memory operand?

include/llvm/Target/TargetInstrDesc.h

@@ -105,6 +105,7 @@ namespace TID {
     IndirectBranch,
     Compare,
     MoveImm,
+    Bitcast,
     DelaySlot,
     FoldableAsLoad,
     MayLoad,
@@ -358,6 +359,12 @@ public:
   bool isMoveImmediate() const {
     return Flags & (1 << TID::MoveImm);
   }
+
+  /// isBitcast - Return true if this instruction is a bitcast instruction.
+  ///
+  bool isBitcast() const {
+    return Flags & (1 << TID::Bitcast);
+  }
   
   /// isNotDuplicable - Return true if this instruction cannot be safely
   /// duplicated.  For example, if the instruction has a unique labels attached