Implement PR5634.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90046 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/InstructionCombining.cpp

@@ -4067,6 +4067,21 @@ Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS,
 /// FoldAndOfICmps - Fold (icmp)&(icmp) if possible.
 Instruction *InstCombiner::FoldAndOfICmps(Instruction &I,
                                           ICmpInst *LHS, ICmpInst *RHS) {
+  // (icmp eq A, null) & (icmp eq B, null) -->
+  //     (icmp eq (ptrtoint(A)|ptrtoint(B)), 0)
+  if (TD &&
+      LHS->getPredicate() == ICmpInst::ICMP_EQ &&
+      RHS->getPredicate() == ICmpInst::ICMP_EQ &&
+      isa<ConstantPointerNull>(LHS->getOperand(1)) &&
+      isa<ConstantPointerNull>(RHS->getOperand(1))) {
+    const Type *IntPtrTy = TD->getIntPtrType(I.getContext());
+    Value *A = Builder->CreatePtrToInt(LHS->getOperand(0), IntPtrTy);
+    Value *B = Builder->CreatePtrToInt(RHS->getOperand(0), IntPtrTy);
+    Value *NewOr = Builder->CreateOr(A, B);
+    return new ICmpInst(ICmpInst::ICMP_EQ, NewOr,
+                        Constant::getNullValue(IntPtrTy));
+  }
+  
   Value *Val, *Val2;
   ConstantInt *LHSCst, *RHSCst;
   ICmpInst::Predicate LHSCC, RHSCC;
@@ -4078,14 +4093,22 @@ Instruction *InstCombiner::FoldAndOfICmps(Instruction &I,
                          m_ConstantInt(RHSCst))))
     return 0;
   
+  if (LHSCst == RHSCst && LHSCC == RHSCC) {
     // (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C)
     // where C is a power of 2
-  if (LHSCst == RHSCst && LHSCC == RHSCC && LHSCC == ICmpInst::ICMP_ULT &&
+    if (LHSCC == ICmpInst::ICMP_ULT &&
         LHSCst->getValue().isPowerOf2()) {
       Value *NewOr = Builder->CreateOr(Val, Val2);
       return new ICmpInst(LHSCC, NewOr, LHSCst);
     }
     
+    // (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0)
+    if (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero()) {
+      Value *NewOr = Builder->CreateOr(Val, Val2);
+      return new ICmpInst(LHSCC, NewOr, LHSCst);
+    }
+  }
+  
   // From here on, we only handle:
   //    (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
   if (Val != Val2) return 0;
@@ -4739,17 +4762,38 @@ static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
 /// FoldOrOfICmps - Fold (icmp)|(icmp) if possible.
 Instruction *InstCombiner::FoldOrOfICmps(Instruction &I,
                                          ICmpInst *LHS, ICmpInst *RHS) {
+  // (icmp ne A, null) | (icmp ne B, null) -->
+  //     (icmp ne (ptrtoint(A)|ptrtoint(B)), 0)
+  if (TD &&
+      LHS->getPredicate() == ICmpInst::ICMP_NE &&
+      RHS->getPredicate() == ICmpInst::ICMP_NE &&
+      isa<ConstantPointerNull>(LHS->getOperand(1)) &&
+      isa<ConstantPointerNull>(RHS->getOperand(1))) {
+    const Type *IntPtrTy = TD->getIntPtrType(I.getContext());
+    Value *A = Builder->CreatePtrToInt(LHS->getOperand(0), IntPtrTy);
+    Value *B = Builder->CreatePtrToInt(RHS->getOperand(0), IntPtrTy);
+    Value *NewOr = Builder->CreateOr(A, B);
+    return new ICmpInst(ICmpInst::ICMP_NE, NewOr,
+                        Constant::getNullValue(IntPtrTy));
+  }
+  
   Value *Val, *Val2;
   ConstantInt *LHSCst, *RHSCst;
   ICmpInst::Predicate LHSCC, RHSCC;
   
   // This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
-  if (!match(LHS, m_ICmp(LHSCC, m_Value(Val),
+  if (!match(LHS, m_ICmp(LHSCC, m_Value(Val), m_ConstantInt(LHSCst))) ||
-             m_ConstantInt(LHSCst))) ||
+      !match(RHS, m_ICmp(RHSCC, m_Value(Val2), m_ConstantInt(RHSCst))))
-      !match(RHS, m_ICmp(RHSCC, m_Value(Val2),
-             m_ConstantInt(RHSCst))))
     return 0;
 
+  
+  // (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
+  if (LHSCst == RHSCst && LHSCC == RHSCC &&
+      LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
+    Value *NewOr = Builder->CreateOr(Val, Val2);
+    return new ICmpInst(LHSCC, NewOr, LHSCst);
+  }
+  
   // From here on, we only handle:
   //    (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
   if (Val != Val2) return 0;

test/Transforms/InstCombine/or.ll

@@ -1,7 +1,8 @@
 ; This test makes sure that these instructions are properly eliminated.
-;
 ; RUN: opt < %s -instcombine -S | FileCheck %s
 
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+
 define i32 @test1(i32 %A) {
         %B = or i32 %A, 0
         ret i32 %B
@@ -253,3 +254,44 @@ define i1 @test25(i32 %A, i32 %B) {
 ; CHECK-NEXT:  %F = and i1 
 ; CHECK-NEXT:  ret i1 %F
 }
+
+; PR5634
+define i1 @test26(i32 %A, i32 %B) {
+        %C1 = icmp eq i32 %A, 0
+        %C2 = icmp eq i32 %B, 0
+        ; (A == 0) & (A == 0)   -->   (A|B) == 0
+        %D = and i1 %C1, %C2
+        ret i1 %D
+; CHECK: @test26
+; CHECK: or i32 %A, %B
+; CHECK: icmp eq i32 {{.*}}, 0
+; CHECK: ret i1 
+}
+
+; PR5634
+define i1 @test27(i32* %A, i32* %B) {
+        %C1 = icmp eq i32* %A, null
+        %C2 = icmp eq i32* %B, null
+        ; (A == 0) & (A == 0)   -->   (A|B) == 0
+        %D = and i1 %C1, %C2
+        ret i1 %D
+; CHECK: @test27
+; CHECK: ptrtoint i32* %A
+; CHECK: ptrtoint i32* %B
+; CHECK: or i32 
+; CHECK: icmp eq i32 {{.*}}, 0
+; CHECK: ret i1 
+}
+
+; PR5634
+define i1 @test28(i32 %A, i32 %B) {
+        %C1 = icmp ne i32 %A, 0
+        %C2 = icmp ne i32 %B, 0
+        ; (A != 0) | (A != 0)   -->   (A|B) != 0
+        %D = or i1 %C1, %C2
+        ret i1 %D
+; CHECK: @test28
+; CHECK: or i32 %A, %B
+; CHECK: icmp ne i32 {{.*}}, 0
+; CHECK: ret i1 
+}