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      1 ; RUN: opt < %s -instcombine -S | FileCheck %s
      2 
      3 ; PR22723: Recognize De Morgan's Laws when obfuscated by zexts.
      4 
      5 define i32 @demorgan_or(i1 %X, i1 %Y) {
      6   %zextX = zext i1 %X to i32
      7   %zextY = zext i1 %Y to i32
      8   %notX  = xor i32 %zextX, 1
      9   %notY  = xor i32 %zextY, 1
     10   %or    = or i32 %notX, %notY
     11   ret i32 %or
     12 
     13 ; CHECK-LABEL: demorgan_or(
     14 ; CHECK-NEXT:  %[[AND:.*]] = and i1 %X, %Y
     15 ; CHECK-NEXT:  %[[ZEXT:.*]] = zext i1 %[[AND]] to i32
     16 ; CHECK-NEXT:  %[[XOR:.*]] = xor i32 %[[ZEXT]], 1
     17 ; CHECK-NEXT:  ret i32 %[[XOR]]
     18 }
     19 
     20 define i32 @demorgan_and(i1 %X, i1 %Y) {
     21   %zextX = zext i1 %X to i32
     22   %zextY = zext i1 %Y to i32
     23   %notX  = xor i32 %zextX, 1
     24   %notY  = xor i32 %zextY, 1
     25   %and   = and i32 %notX, %notY
     26   ret i32 %and
     27 
     28 ; CHECK-LABEL: demorgan_and(
     29 ; CHECK-NEXT:  %[[OR:.*]] = or i1 %X, %Y
     30 ; CHECK-NEXT:  %[[ZEXT:.*]] = zext i1 %[[OR]] to i32
     31 ; CHECK-NEXT:  %[[XOR:.*]] = xor i32 %[[ZEXT]], 1
     32 ; CHECK-NEXT:  ret i32 %[[XOR]]
     33 }
     34 
     35