[clang] [clang][bytecode] Add opaque pointers to support type-only pointers (PR #213017)

[Timm Baeder via cfe-commits]

Timm =?utf-8?q?Bäder?= <tbaeder at redhat.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/213017 at github.com>


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@@ -2524,14 +2315,28 @@ static bool interp__builtin_object_size(InterpState &S, CodePtr OpPC,
   if (Call->getArg(0)->HasSideEffects(ASTCtx)) {
     // "If there are any side effects in them, it returns (size_t) -1
     // for type 0 or 1 and (size_t) 0 for type 2 or 3."
-    pushInteger(S, Kind <= 1 ? -1 : 0, Call->getType());
+    pushInteger(S, Kind <= 1 ? (size_t)-1 : (size_t)0, Call->getType());
     return true;
   }
 
-  if (auto Result = evaluateBuiltinObjectSize(ASTCtx, Kind, Ptr)) {
+  if (auto Result = evaluateBuiltinObjectSize(ASTCtx, Kind, Ptr,
+                                              Call->getArg(0), IsDynamic)) {
     pushInteger(S, *Result, Call->getType());
     return true;
   }
+
+  switch (S.EvalMode) {
+  case EvaluationMode::ConstantExpression:
+  case EvaluationMode::ConstantFold:
+  case EvaluationMode::IgnoreSideEffects:
+    // Leave it to IR generation.
+    return Invalid(S, OpPC);
+  case EvaluationMode::ConstantExpressionUnevaluated:
+    // Reduce it to a constant now.
+    pushInteger(S, ((Kind & 2u) ? (size_t)0 : (size_t)-1), Call->getType());
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tbaederr wrote:

Not sure what that is, this is just what the Kind/Type parameter to `__builtin_object_size` is.

https://github.com/llvm/llvm-project/pull/213017