[clang] nonblocking/nonallocating attributes (was: nolock/noalloc) (PR #84983)

[Doug Wyatt via cfe-commits]

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@@ -3637,6 +3637,28 @@ FunctionProtoType::FunctionProtoType(QualType result, ArrayRef<QualType> params,
     auto &EllipsisLoc = *getTrailingObjects<SourceLocation>();
     EllipsisLoc = epi.EllipsisLoc;
   }
+
+  if (!epi.FunctionEffects.empty()) {
+    auto &ExtraBits = *getTrailingObjects<FunctionTypeExtraBitfields>();
+    // TODO: bitfield overflow?
+    ExtraBits.NumFunctionEffects = epi.FunctionEffects.size();
+
+    ArrayRef<FunctionEffect> SrcFX = epi.FunctionEffects.effects();
+    auto *DestFX = getTrailingObjects<FunctionEffect>();
+    std::copy(SrcFX.begin(), SrcFX.end(), DestFX);
+
+    ArrayRef<FunctionEffectCondition> SrcConds =
+        epi.FunctionEffects.conditions();
+    if (!SrcConds.empty()) {
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dougsonos wrote:

TODO: Clean up invariants -- if a non-empty vector signals a dependent expression, then when nulling a vector element, we should check to see if all elements are null and clear it if so.

https://github.com/llvm/llvm-project/pull/84983