[llvm] r211252 - Move optimization of some cases of (A & C1)|(B & C2) from instcombine to instsimplify. Patch by Rahul Jain, plus some last minute changes by me -- you can blame me for any bugs.

[Nick Lewycky]

Author: nicholas
Date: Wed Jun 18 22:51:46 2014
New Revision: 211252

URL: http://llvm.org/viewvc/llvm-project?rev=211252&view=rev
Log:
Move optimization of some cases of (A & C1)|(B & C2) from instcombine to instsimplify. Patch by Rahul Jain, plus some last minute changes by me -- you can blame me for any bugs.

Added:
    llvm/trunk/test/Transforms/InstSimplify/apint-or.ll
Modified:
    llvm/trunk/lib/Analysis/InstructionSimplify.cpp
    llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp

Modified: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/InstructionSimplify.cpp?rev=211252&r1=211251&r2=211252&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/InstructionSimplify.cpp (original)
+++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp Wed Jun 18 22:51:46 2014
@@ -1625,6 +1625,38 @@ static Value *SimplifyOrInst(Value *Op0,
                                          MaxRecurse))
       return V;
 
+  // (A & C)|(B & D)
+  Value *C = nullptr, *D = nullptr;
+  if (match(Op0, m_And(m_Value(A), m_Value(C))) &&
+      match(Op1, m_And(m_Value(B), m_Value(D)))) {
+    ConstantInt *C1 = dyn_cast<ConstantInt>(C);
+    ConstantInt *C2 = dyn_cast<ConstantInt>(D);
+    if (C1 && C2 && (C1->getValue() == ~C2->getValue())) {
+      // (A & C1)|(B & C2)
+      // If we have: ((V + N) & C1) | (V & C2)
+      // .. and C2 = ~C1 and C2 is 0+1+ and (N & C2) == 0
+      // replace with V+N.
+      Value *V1, *V2;
+      if ((C2->getValue() & (C2->getValue() + 1)) == 0 && // C2 == 0+1+
+          match(A, m_Add(m_Value(V1), m_Value(V2)))) {
+        // Add commutes, try both ways.
+        if (V1 == B && MaskedValueIsZero(V2, C2->getValue()))
+          return A;
+        if (V2 == B && MaskedValueIsZero(V1, C2->getValue()))
+          return A;
+      }
+      // Or commutes, try both ways.
+      if ((C1->getValue() & (C1->getValue() + 1)) == 0 &&
+          match(B, m_Add(m_Value(V1), m_Value(V2)))) {
+        // Add commutes, try both ways.
+        if (V1 == A && MaskedValueIsZero(V2, C1->getValue()))
+          return B;
+        if (V2 == A && MaskedValueIsZero(V1, C1->getValue()))
+          return B;
+      }
+    }
+  }
+
   // If the operation is with the result of a phi instruction, check whether
   // operating on all incoming values of the phi always yields the same value.
   if (isa<PHINode>(Op0) || isa<PHINode>(Op1))

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp?rev=211252&r1=211251&r2=211252&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp Wed Jun 18 22:51:46 2014
@@ -1996,29 +1996,6 @@ Instruction *InstCombiner::visitOr(Binar
     C1 = dyn_cast<ConstantInt>(C);
     C2 = dyn_cast<ConstantInt>(D);
     if (C1 && C2) {  // (A & C1)|(B & C2)
-      // If we have: ((V + N) & C1) | (V & C2)
-      // .. and C2 = ~C1 and C2 is 0+1+ and (N & C2) == 0
-      // replace with V+N.
-      if (C1->getValue() == ~C2->getValue()) {
-        if ((C2->getValue() & (C2->getValue()+1)) == 0 && // C2 == 0+1+
-            match(A, m_Add(m_Value(V1), m_Value(V2)))) {
-          // Add commutes, try both ways.
-          if (V1 == B && MaskedValueIsZero(V2, C2->getValue()))
-            return ReplaceInstUsesWith(I, A);
-          if (V2 == B && MaskedValueIsZero(V1, C2->getValue()))
-            return ReplaceInstUsesWith(I, A);
-        }
-        // Or commutes, try both ways.
-        if ((C1->getValue() & (C1->getValue()+1)) == 0 &&
-            match(B, m_Add(m_Value(V1), m_Value(V2)))) {
-          // Add commutes, try both ways.
-          if (V1 == A && MaskedValueIsZero(V2, C1->getValue()))
-            return ReplaceInstUsesWith(I, B);
-          if (V2 == A && MaskedValueIsZero(V1, C1->getValue()))
-            return ReplaceInstUsesWith(I, B);
-        }
-      }
-
       if ((C1->getValue() & C2->getValue()) == 0) {
         // ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
         // iff (C1&C2) == 0 and (N&~C1) == 0

Added: llvm/trunk/test/Transforms/InstSimplify/apint-or.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstSimplify/apint-or.ll?rev=211252&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/InstSimplify/apint-or.ll (added)
+++ llvm/trunk/test/Transforms/InstSimplify/apint-or.ll Wed Jun 18 22:51:46 2014
@@ -0,0 +1,37 @@
+; RUN: opt < %s -instsimplify -S | not grep or
+
+; Test the case where integer BitWidth <= 64 && BitWidth % 2 != 0.
+define i39 @test1(i39 %V, i39 %M) {
+    ;; If we have: ((V + N) & C1) | (V & C2)
+    ;; .. and C2 = ~C1 and C2 is 0+1+ and (N & C2) == 0
+    ;; replace with V+N.
+    %C1 = xor i39 274877906943, -1 ;; C2 = 274877906943
+    %N = and i39 %M, 274877906944
+    %A = add i39 %V, %N
+    %B = and i39 %A, %C1
+    %D = and i39 %V, 274877906943
+    %R = or i39 %B, %D
+    ret i39 %R
+; CHECK-LABEL @test1
+; CHECK-NEXT: and {{.*}}, -274877906944
+; CHECK-NEXT: add
+; CHECK-NEXT: ret
+}
+
+; Test the case where Integer BitWidth > 64 && BitWidth <= 1024. 
+define i399 @test2(i399 %V, i399 %M) {
+    ;; If we have: ((V + N) & C1) | (V & C2)
+    ;; .. and C2 = ~C1 and C2 is 0+1+ and (N & C2) == 0
+    ;; replace with V+N.
+    %C1 = xor i399 274877906943, -1 ;; C2 = 274877906943
+    %N = and i399 %M, 18446742974197923840
+    %A = add i399 %V, %N
+    %B = and i399 %A, %C1
+    %D = and i399 %V, 274877906943
+    %R = or i399 %B, %D
+    ret i399 %R
+; CHECK-LABEL @test2
+; CHECK-NEXT: and {{.*}}, 18446742974197923840
+; CHECK-NEXT: add
+; CHECK-NEXT: ret
+}