Index: llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
===================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -2276,7 +2276,8 @@
 
 /// A ^ B can be specified using other logic ops in a variety of patterns. We
 /// can fold these early and efficiently by morphing an existing instruction.
-static Instruction *foldXorToXor(BinaryOperator &I) {
+static Instruction *foldXorToXor(BinaryOperator &I,
+                                 InstCombiner::BuilderTy &Builder) {
   assert(I.getOpcode() == Instruction::Xor);
   Value *Op0 = I.getOperand(0);
   Value *Op1 = I.getOperand(1);
@@ -2323,6 +2324,21 @@
     return &I;
   }
 
+  // For the remaining cases we need to get rid of one of the operands.
+  if (!Op0->hasOneUse() && !Op1->hasOneUse())
+    return nullptr;
+
+  // (A | B) ^ ~(A & B) -> ~(A ^ B)
+  // (A | B) ^ ~(B & A) -> ~(A ^ B)
+  // (A & B) ^ ~(A | B) -> ~(A ^ B)
+  // (A & B) ^ ~(B | A) -> ~(A ^ B)
+  // Complexity sorting ensures the not will be on the right side.
+  if ((match(Op0, m_Or(m_Value(A), m_Value(B))) &&
+       match(Op1, m_Not(m_c_And(m_Specific(A), m_Specific(B))))) ||
+      (match(Op0, m_And(m_Value(A), m_Value(B))) &&
+       match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B))))))
+    return BinaryOperator::CreateNot(Builder.CreateXor(A, B));
+
   return nullptr;
 }
 
@@ -2381,7 +2397,7 @@
   if (Value *V = SimplifyXorInst(Op0, Op1, SQ.getWithInstruction(&I)))
     return replaceInstUsesWith(I, V);
 
-  if (Instruction *NewXor = foldXorToXor(I))
+  if (Instruction *NewXor = foldXorToXor(I, *Builder))
     return NewXor;
 
   // (A&B)^(A&C) -> A&(B^C) etc
Index: llvm/trunk/test/Transforms/InstCombine/and-or-not.ll
===================================================================
--- llvm/trunk/test/Transforms/InstCombine/and-or-not.ll
+++ llvm/trunk/test/Transforms/InstCombine/and-or-not.ll
@@ -570,10 +570,8 @@
 ; CHECK-LABEL: @xor_to_xnor1(
 ; CHECK-NEXT:    [[A:%.*]] = fptosi float [[FA:%.*]] to i32
 ; CHECK-NEXT:    [[B:%.*]] = fptosi float [[FB:%.*]] to i32
-; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[A]], [[B]]
-; CHECK-NEXT:    [[OR2_DEMORGAN:%.*]] = and i32 [[A]], [[B]]
-; CHECK-NEXT:    [[OR2:%.*]] = xor i32 [[OR2_DEMORGAN]], -1
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR1]], [[OR2]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[A]], [[B]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %a = fptosi float %fa to i32
@@ -591,10 +589,8 @@
 ; CHECK-LABEL: @xor_to_xnor2(
 ; CHECK-NEXT:    [[A:%.*]] = fptosi float [[FA:%.*]] to i32
 ; CHECK-NEXT:    [[B:%.*]] = fptosi float [[FB:%.*]] to i32
-; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[A]], [[B]]
-; CHECK-NEXT:    [[OR2_DEMORGAN:%.*]] = and i32 [[B]], [[A]]
-; CHECK-NEXT:    [[OR2:%.*]] = xor i32 [[OR2_DEMORGAN]], -1
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR1]], [[OR2]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[A]], [[B]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %a = fptosi float %fa to i32
@@ -612,10 +608,8 @@
 ; CHECK-LABEL: @xor_to_xnor3(
 ; CHECK-NEXT:    [[A:%.*]] = fptosi float [[FA:%.*]] to i32
 ; CHECK-NEXT:    [[B:%.*]] = fptosi float [[FB:%.*]] to i32
-; CHECK-NEXT:    [[OR1_DEMORGAN:%.*]] = and i32 [[A]], [[B]]
-; CHECK-NEXT:    [[OR1:%.*]] = xor i32 [[OR1_DEMORGAN]], -1
-; CHECK-NEXT:    [[OR2:%.*]] = or i32 [[A]], [[B]]
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR2]], [[OR1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[A]], [[B]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %a = fptosi float %fa to i32
@@ -633,10 +627,8 @@
 ; CHECK-LABEL: @xor_to_xnor4(
 ; CHECK-NEXT:    [[A:%.*]] = fptosi float [[FA:%.*]] to i32
 ; CHECK-NEXT:    [[B:%.*]] = fptosi float [[FB:%.*]] to i32
-; CHECK-NEXT:    [[OR1_DEMORGAN:%.*]] = and i32 [[A]], [[B]]
-; CHECK-NEXT:    [[OR1:%.*]] = xor i32 [[OR1_DEMORGAN]], -1
-; CHECK-NEXT:    [[OR2:%.*]] = or i32 [[B]], [[A]]
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR2]], [[OR1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[B]], [[A]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %a = fptosi float %fa to i32
Index: llvm/trunk/test/Transforms/InstCombine/or-xor.ll
===================================================================
--- llvm/trunk/test/Transforms/InstCombine/or-xor.ll
+++ llvm/trunk/test/Transforms/InstCombine/or-xor.ll
@@ -348,10 +348,8 @@
 ; ((x | y) ^ (~x | ~y)) -> ~(x ^ y)
 define i32 @test19(i32 %x, i32 %y) {
 ; CHECK-LABEL: @test19(
-; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[OR2_DEMORGAN:%.*]] = and i32 [[X]], [[Y]]
-; CHECK-NEXT:    [[OR2:%.*]] = xor i32 [[OR2_DEMORGAN]], -1
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR1]], [[OR2]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %noty = xor i32 %y, -1
@@ -365,10 +363,8 @@
 ; ((x | y) ^ (~y | ~x)) -> ~(x ^ y)
 define i32 @test20(i32 %x, i32 %y) {
 ; CHECK-LABEL: @test20(
-; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[OR2_DEMORGAN:%.*]] = and i32 [[Y]], [[X]]
-; CHECK-NEXT:    [[OR2:%.*]] = xor i32 [[OR2_DEMORGAN]], -1
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR1]], [[OR2]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %noty = xor i32 %y, -1
@@ -382,10 +378,8 @@
 ; ((~x | ~y) ^ (x | y)) -> ~(x ^ y)
 define i32 @test21(i32 %x, i32 %y) {
 ; CHECK-LABEL: @test21(
-; CHECK-NEXT:    [[OR1_DEMORGAN:%.*]] = and i32 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[OR1:%.*]] = xor i32 [[OR1_DEMORGAN]], -1
-; CHECK-NEXT:    [[OR2:%.*]] = or i32 [[X]], [[Y]]
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR2]], [[OR1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %noty = xor i32 %y, -1
@@ -399,10 +393,8 @@
 ; ((~x | ~y) ^ (y | x)) -> ~(x ^ y)
 define i32 @test22(i32 %x, i32 %y) {
 ; CHECK-LABEL: @test22(
-; CHECK-NEXT:    [[OR1_DEMORGAN:%.*]] = and i32 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[OR1:%.*]] = xor i32 [[OR1_DEMORGAN]], -1
-; CHECK-NEXT:    [[OR2:%.*]] = or i32 [[Y]], [[X]]
-; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[OR2]], [[OR1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i32 [[Y:%.*]], [[X:%.*]]
+; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[TMP1]], -1
 ; CHECK-NEXT:    ret i32 [[XOR]]
 ;
   %noty = xor i32 %y, -1