[clang][Interp] Fix casting pointers to int128

Author: tbaederr

clang/lib/AST/Interp/ByteCodeExprGen.cpp

@@ -194,6 +194,12 @@ bool ByteCodeExprGen<Emitter>::VisitCastExpr(const CastExpr *CE) {
       return false;
 
     PrimType T = classifyPrim(CE->getType());
+    if (T == PT_IntAP)
+      return this->emitCastPointerIntegralAP(Ctx.getBitWidth(CE->getType()),
+                                             CE);
+    if (T == PT_IntAPS)
+      return this->emitCastPointerIntegralAPS(Ctx.getBitWidth(CE->getType()),
+                                              CE);
     return this->emitCastPointerIntegral(T, CE);
   }
 

clang/lib/AST/Interp/Interp.h

@@ -1833,6 +1833,32 @@ bool CastPointerIntegral(InterpState &S, CodePtr OpPC) {
   return true;
 }
 
+static inline bool CastPointerIntegralAP(InterpState &S, CodePtr OpPC,
+                                         uint32_t BitWidth) {
+  const Pointer &Ptr = S.Stk.pop<Pointer>();
+
+  const SourceInfo &E = S.Current->getSource(OpPC);
+  S.CCEDiag(E, diag::note_constexpr_invalid_cast)
+      << 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
+
+  S.Stk.push<IntegralAP<false>>(
+      IntegralAP<false>::from(Ptr.getIntegerRepresentation(), BitWidth));
+  return true;
+}
+
+static inline bool CastPointerIntegralAPS(InterpState &S, CodePtr OpPC,
+                                          uint32_t BitWidth) {
+  const Pointer &Ptr = S.Stk.pop<Pointer>();
+
+  const SourceInfo &E = S.Current->getSource(OpPC);
+  S.CCEDiag(E, diag::note_constexpr_invalid_cast)
+      << 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
+
+  S.Stk.push<IntegralAP<true>>(
+      IntegralAP<true>::from(Ptr.getIntegerRepresentation(), BitWidth));
+  return true;
+}
+
 //===----------------------------------------------------------------------===//
 // Zero, Nullptr
 //===----------------------------------------------------------------------===//

clang/lib/AST/Interp/Opcodes.td

@@ -664,10 +664,19 @@ def CastFloatingIntegralAPS : Opcode {
 }
 
 def CastPointerIntegral : Opcode {
-  let Types = [AluTypeClass];
-  let Args = [];
+  let Types = [FixedSizeIntegralTypeClass];
   let HasGroup = 1;
 }
+def CastPointerIntegralAP : Opcode {
+  let Types = [];
+  let HasGroup = 0;
+  let Args = [ArgUint32];
+}
+def CastPointerIntegralAPS : Opcode {
+  let Types = [];
+  let HasGroup = 0;
+  let Args = [ArgUint32];
+}
 
 def DecayPtr : Opcode {
   let Types = [PtrTypeClass, PtrTypeClass];

clang/test/AST/Interp/c.c

@@ -257,3 +257,9 @@ int Y __attribute__((annotate(
   42,
   (struct TestStruct) { .a = 1, .b = 2 }
 )));
+
+#ifdef __SIZEOF_INT128__
+const int *p = &b;
+const __int128 K = (__int128)(int*)0;
+const unsigned __int128 KU = (unsigned __int128)(int*)0;
+#endif