Move some those Xor simplifications which don't require creating new

instructions out of InstCombine and into InstructionSimplify.  While
there, introduce an m_AllOnes pattern to simplify matching with integers
and vectors with all bits equal to one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119536 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 20 insertions, 1 deletions

diff --git a/include/llvm/Analysis/InstructionSimplify.h b/include/llvm/Analysis/InstructionSimplify.h
index 965e71b..f88fc46 100644
--- a/include/llvm/Analysis/InstructionSimplify.h
+++ b/include/llvm/Analysis/InstructionSimplify.h
@@ -37,6 +37,11 @@ namespace llvm {
   Value *SimplifyOrInst(Value *LHS, Value *RHS, const TargetData *TD = 0,
                         const DominatorTree *DT = 0);
 
+  /// SimplifyXorInst - Given operands for a Xor, see if we can
+  /// fold the result.  If not, this returns null.
+  Value *SimplifyXorInst(Value *LHS, Value *RHS, const TargetData *TD = 0,
+                         const DominatorTree *DT = 0);
+
   /// SimplifyICmpInst - Given operands for an ICmpInst, see if we can
   /// fold the result.  If not, this returns null.
   Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
diff --git a/include/llvm/Support/PatternMatch.h b/include/llvm/Support/PatternMatch.h
index bee6768..8b58121 100644
--- a/include/llvm/Support/PatternMatch.h
+++ b/include/llvm/Support/PatternMatch.h
@@ -96,9 +96,23 @@ struct one_ty {
   }
 };
 
-/// m_One() - Match a an integer 1.
+/// m_One() - Match an integer 1.
 inline one_ty m_One() { return one_ty(); }
   
+struct all_ones_ty {
+  template<typename ITy>
+  bool match(ITy *V) {
+    if (const ConstantInt *C = dyn_cast<ConstantInt>(V))
+      return C->isAllOnesValue();
+    if (const ConstantVector *C = dyn_cast<ConstantVector>(V))
+      return C->isAllOnesValue();
+    return false;
+  }
+};
+
+/// m_AllOnes() - Match an integer or vector with all bits set to true.
+inline all_ones_ty m_AllOnes() { return all_ones_ty(); }
+
 
 template<typename Class>
 struct bind_ty {