Revert "[clang][Interp] Basic support for bit fields"

This reverts commit 8065b1cc133c9e4b6900d5c11220617180706b94.

This breaks builders. I forgot this depends
on https://reviews.llvm.org/D155548

5 files changed, 13 insertions, 73 deletions

diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index 4c0b599..8a756e4f 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -305,10 +305,8 @@ bool ByteCodeExprGen<Emitter>::VisitBinaryOperator(const BinaryOperator *BO) {
     return Discard(this->emitDiv(*T, BO));
   case BO_Assign:
     if (DiscardResult)
-      return LHS->refersToBitField() ? this->emitStoreBitFieldPop(*T, BO)
-                                     : this->emitStorePop(*T, BO);
-    return LHS->refersToBitField() ? this->emitStoreBitField(*T, BO)
-                                   : this->emitStore(*T, BO);
+      return this->emitStorePop(*T, BO);
+    return this->emitStore(*T, BO);
   case BO_And:
     return Discard(this->emitBitAnd(*T, BO));
   case BO_Or:
@@ -1592,13 +1590,8 @@ bool ByteCodeExprGen<Emitter>::visitRecordInitializer(const Expr *Initializer) {
         if (!this->visit(Init))
           return false;
 
-        if (FieldToInit->isBitField()) {
-          if (!this->emitInitBitField(*T, FieldToInit, Initializer))
-            return false;
-        } else {
-          if (!this->emitInitField(*T, FieldToInit->Offset, Initializer))
-            return false;
-        }
+        if (!this->emitInitField(*T, FieldToInit->Offset, Initializer))
+          return false;
 
         if (!this->emitPopPtr(Initializer))
           return false;
diff --git a/clang/lib/AST/Interp/ByteCodeStmtGen.cpp b/clang/lib/AST/Interp/ByteCodeStmtGen.cpp
index cce7067..e54805c 100644
--- a/clang/lib/AST/Interp/ByteCodeStmtGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeStmtGen.cpp
@@ -169,13 +169,8 @@ bool ByteCodeStmtGen<Emitter>::visitFunc(const FunctionDecl *F) {
           if (!this->visit(InitExpr))
             return false;
 
-          if (F->isBitField()) {
-            if (!this->emitInitThisBitField(*T, F, InitExpr))
-              return false;
-          } else {
-            if (!this->emitInitThisField(*T, F->Offset, InitExpr))
-              return false;
-          }
+          if (!this->emitInitThisField(*T, F->Offset, InitExpr))
+            return false;
         } else {
           // Non-primitive case. Get a pointer to the field-to-initialize
           // on the stack and call visitInitialzer() for it.
diff --git a/clang/lib/AST/Interp/Interp.h b/clang/lib/AST/Interp/Interp.h
index f1fb4e3..c278144 100644
--- a/clang/lib/AST/Interp/Interp.h
+++ b/clang/lib/AST/Interp/Interp.h
@@ -1007,7 +1007,6 @@ bool InitThisField(InterpState &S, CodePtr OpPC, uint32_t I) {
 
 template <PrimType Name, class T = typename PrimConv<Name>::T>
 bool InitThisBitField(InterpState &S, CodePtr OpPC, const Record::Field *F) {
-  assert(F->isBitField());
   if (S.checkingPotentialConstantExpression())
     return false;
   const Pointer &This = S.Current->getThis();
@@ -1049,9 +1048,8 @@ bool InitField(InterpState &S, CodePtr OpPC, uint32_t I) {
 
 template <PrimType Name, class T = typename PrimConv<Name>::T>
 bool InitBitField(InterpState &S, CodePtr OpPC, const Record::Field *F) {
-  assert(F->isBitField());
   const T &Value = S.Stk.pop<T>();
-  const Pointer &Field = S.Stk.peek<Pointer>().atField(F->Offset);
+  const Pointer &Field = S.Stk.pop<Pointer>().atField(F->Offset);
   Field.deref<T>() = Value.truncate(F->Decl->getBitWidthValue(S.getCtx()));
   Field.activate();
   Field.initialize();
@@ -1249,10 +1247,11 @@ bool StoreBitField(InterpState &S, CodePtr OpPC) {
     return false;
   if (!Ptr.isRoot())
     Ptr.initialize();
-  if (const auto *FD = Ptr.getField())
+  if (auto *FD = Ptr.getField()) {
     Ptr.deref<T>() = Value.truncate(FD->getBitWidthValue(S.getCtx()));
-  else
+  } else {
     Ptr.deref<T>() = Value;
+  }
   return true;
 }
 
@@ -1264,10 +1263,11 @@ bool StoreBitFieldPop(InterpState &S, CodePtr OpPC) {
     return false;
   if (!Ptr.isRoot())
     Ptr.initialize();
-  if (const auto *FD = Ptr.getField())
+  if (auto *FD = Ptr.getField()) {
     Ptr.deref<T>() = Value.truncate(FD->getBitWidthValue(S.getCtx()));
-  else
+  } else {
     Ptr.deref<T>() = Value;
+  }
   return true;
 }
 
diff --git a/clang/lib/AST/Interp/Record.h b/clang/lib/AST/Interp/Record.h
index 5219734f..940b4c9 100644
--- a/clang/lib/AST/Interp/Record.h
+++ b/clang/lib/AST/Interp/Record.h
@@ -29,7 +29,6 @@ public:
     const FieldDecl *Decl;
     unsigned Offset;
     Descriptor *Desc;
-    bool isBitField() const { return Decl->isBitField(); }
   };
 
   /// Describes a base class.
diff --git a/clang/test/AST/Interp/bitfields.cpp b/clang/test/AST/Interp/bitfields.cpp
deleted file mode 100644
index e078704..0000000
--- a/clang/test/AST/Interp/bitfields.cpp
+++ /dev/null
@@ -1,47 +0,0 @@
-// RUN: %clang_cc1 -fexperimental-new-constant-interpreter -Wno-bitfield-constant-conversion -verify %s
-// RUN: %clang_cc1 -verify=ref -Wno-bitfield-constant-conversion %s
-
-// expected-no-diagnostics
-// ref-no-diagnostics
-
-namespace Basic {
-  struct A {
-    unsigned int a : 2;
-    constexpr A() : a(0) {}
-    constexpr A(int a) : a(a) {}
-  };
-
-  constexpr A a{1};
-  static_assert(a.a == 1, "");
-
-  constexpr A a2{10};
-  static_assert(a2.a == 2, "");
-
-
-  constexpr int storeA() {
-    A a;
-    a.a = 10;
-
-    return a.a;
-  }
-  static_assert(storeA() == 2, "");
-
-  constexpr int storeA2() {
-    A a;
-    return a.a = 10;
-  }
-  static_assert(storeA2() == 2, "");
-
-  // TODO: +=, -=, etc. operators.
-}
-
-namespace Overflow {
-  struct A {int c:3;};
-
-  constexpr int f() {
-    A a1{3};
-    return a1.c++;
-  }
-
-  static_assert(f() == 3, "");
-}