Add a "Compare" flag to the target instruction descriptor. This will be used

later to identify and possibly remove superfluous compare instructions -- those
that are testing for and setting a status flag that should already be set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109901 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 8 insertions, 1 deletions

diff --git a/include/llvm/Target/Target.td b/include/llvm/Target/Target.td
index ad1a816..809e088 100644
--- a/include/llvm/Target/Target.td
+++ b/include/llvm/Target/Target.td
@@ -198,6 +198,7 @@ class Instruction {
   bit isReturn     = 0;     // Is this instruction a return instruction?
   bit isBranch     = 0;     // Is this instruction a branch instruction?
   bit isIndirectBranch = 0; // Is this instruction an indirect branch?
+  bit isCompare    = 0;     // Is this instruction a comparison 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?
diff --git a/include/llvm/Target/TargetInstrDesc.h b/include/llvm/Target/TargetInstrDesc.h
index 8f0a6cb..6a08e8f 100644
--- a/include/llvm/Target/TargetInstrDesc.h
+++ b/include/llvm/Target/TargetInstrDesc.h
@@ -105,6 +105,7 @@ namespace TID {
     IndirectBranch,
     Predicable,
     NotDuplicable,
+    Compare,
     DelaySlot,
     FoldableAsLoad,
     MayLoad,
@@ -315,7 +316,7 @@ public:
   bool isIndirectBranch() const {
     return Flags & (1 << TID::IndirectBranch);
   }
-  
+
   /// isConditionalBranch - Return true if this is a branch which may fall
   /// through to the next instruction or may transfer control flow to some other
   /// block.  The TargetInstrInfo::AnalyzeBranch method can be used to get more
@@ -340,6 +341,11 @@ public:
     return Flags & (1 << TID::Predicable);
   }
   
+  /// isCompare - Return true if this instruction is a comparison.
+  bool isCompare() const {
+    return Flags & (1 << TID::Compare);
+  }
+  
   /// isNotDuplicable - Return true if this instruction cannot be safely
   /// duplicated.  For example, if the instruction has a unique labels attached
   /// to it, duplicating it would cause multiple definition errors.