[clang][Interp] Implement bitwise and operations

[shafik]

clang/lib/AST/Interp/Integral.h

220

Maybe bitAnd?

clang/test/AST/Interp/literals.cpp

269

Also 0 & something else should be 0.

I wonder if there is any value in using binary literals.

[shafik]

LGTM

clang/test/AST/Interp/literals.cpp

270

Why gimme(12) and not just 12?

[tbaeder]

clang/test/AST/Interp/literals.cpp

270

I just thought it might be useful to test something that's not a literal.

clang/lib/AST/Interp/ByteCodeExprGen.cpp

if (Optional<PrimType> T = classify(BO->getType())) {
     case BO_Rem:
       return Discard(this->emitRem(*T, BO));
     case BO_Div:
       return Discard(this->emitDiv(*T, BO));
     case BO_Assign:
       if (!this->emitStore(*T, BO))
         return false;
       return DiscardResult ? this->emitPopPtr(BO) : true;
+    case BO_And:
+      return Discard(this->emitBitAnd(*T, BO));
+    case BO_Or:
+    case BO_LAnd:
+    case BO_LOr:
     default:
       return this->bail(BO);
     }
   }
 
   return this->bail(BO);
 }
 

clang/lib/AST/Interp/Integral.h

static bool rem(Integral A, Integral B, unsigned OpBits, Integral *R) {
     return false;
   }
 
   static bool div(Integral A, Integral B, unsigned OpBits, Integral *R) {
     *R = Integral(A.V / B.V);
     return false;
   }
 
+  static bool bitAnd(Integral A, Integral B, unsigned OpBits, Integral *R) {
+    *R = Integral(A.V & B.V);
+    return false;
+  }
+
   static bool neg(Integral A, Integral *R) {
     *R = -A;
     return false;
   }
 
   static bool comp(Integral A, Integral *R) {
     *R = Integral(~A.V);
     return false;

clang/lib/AST/Interp/Interp.h

bool Mul(InterpState &S, CodePtr OpPC) {
   const T &RHS = S.Stk.pop<T>();
   const T &LHS = S.Stk.pop<T>();
   const unsigned Bits = RHS.bitWidth() * 2;
   return AddSubMulHelper<T, T::mul, std::multiplies>(S, OpPC, Bits, LHS, RHS);
 }
 
 /// 1) Pops the RHS from the stack.
 /// 2) Pops the LHS from the stack.
+/// 3) Pushes 'LHS & RHS' on the stack
+template <PrimType Name, class T = typename PrimConv<Name>::T>
+bool BitAnd(InterpState &S, CodePtr OpPC) {
+  const T &RHS = S.Stk.pop<T>();
+  const T &LHS = S.Stk.pop<T>();
+
+  unsigned Bits = RHS.bitWidth();
+  T Result;
+  if (!T::bitAnd(LHS, RHS, Bits, &Result)) {
+    S.Stk.push<T>(Result);
+    return true;
+  }
+  return false;
+}
+
+/// 1) Pops the RHS from the stack.
+/// 2) Pops the LHS from the stack.
 /// 3) Pushes 'LHS % RHS' on the stack (the remainder of dividing LHS by RHS).
 template <PrimType Name, class T = typename PrimConv<Name>::T>
 bool Rem(InterpState &S, CodePtr OpPC) {
   const T &RHS = S.Stk.pop<T>();
   const T &LHS = S.Stk.pop<T>();
 
   if (RHS.isZero()) {
     const SourceInfo &Loc = S.Current->getSource(OpPC);

clang/lib/AST/Interp/Opcodes.td

class TypeClass {
   list<Type> Types;
 }
 
 def NumberTypeClass : TypeClass {
   let Types = [Sint8, Uint8, Sint16, Uint16, Sint32,
                Uint32, Sint64, Uint64];
 }
 
+def IntegerTypeClass : TypeClass {
+  let Types = [Sint8, Uint8, Sint16, Uint16, Sint32,
+               Uint32, Sint64, Uint64];
+}
+
 def AluTypeClass : TypeClass {
   let Types = !listconcat(NumberTypeClass.Types, [Bool]);
 }
 
 def PtrTypeClass : TypeClass {
   let Types = [Ptr];
 }
 
class Opcode {
   bit HasGroup = 0;
 }
 
 class AluOpcode : Opcode {
   let Types = [AluTypeClass];
   let HasGroup = 1;
 }
 
+class IntegerOpcode : Opcode {
+  let Types = [IntegerTypeClass];
+  let HasGroup = 1;
+}
+
 //===----------------------------------------------------------------------===//
 // Jump opcodes
 //===----------------------------------------------------------------------===//
 
 class JumpOpcode : Opcode {
   let Args = [ArgSint32];
   let ChangesPC = 1;
   let HasCustomEval = 1;

 // [Real, Real] -> [Real]
 def Sub : AluOpcode;
 def Add : AluOpcode;
 def Mul : AluOpcode;
 def Rem : Opcode {
   let Types = [NumberTypeClass];
   let HasGroup = 1;
 }
+def BitAnd : IntegerOpcode;
 def Div : Opcode {
   let Types = [NumberTypeClass];
   let HasGroup = 1;
 }
 
 //===----------------------------------------------------------------------===//
 // Unary operators.
 //===----------------------------------------------------------------------===//

clang/test/AST/Interp/literals.cpp

#if __cplusplus >= 201402L
   }
 
   static_assert(testCond() == 5, "");
   static_assert(testCond2() == 10, "");
 
 #endif
 
 };
+
+namespace band {
+  static_assert((10 & 1) == 0, "");
+  static_assert((10 & 10) == 10, "");
+
+  static_assert((1337 & -1) == 1337, "");
+  static_assert((0 & gimme(12)) == 0, "");
+};