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

[Chris Apple via cfe-commits]

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@@ -7963,6 +7967,148 @@ static Attr *getCCTypeAttr(ASTContext &Ctx, ParsedAttr &Attr) {
   llvm_unreachable("unexpected attribute kind!");
 }
 
+ExprResult Sema::ActOnEffectExpression(Expr *CondExpr, FunctionEffectMode &Mode,
+                                       bool RequireConstexpr) {
+  // see checkFunctionConditionAttr, Sema::CheckCXXBooleanCondition
+  if (RequireConstexpr || !CondExpr->isTypeDependent()) {
+    ExprResult E = PerformContextuallyConvertToBool(CondExpr);
+    if (E.isInvalid())
+      return E;
+    CondExpr = E.get();
+    if (RequireConstexpr || !CondExpr->isValueDependent()) {
+      llvm::APSInt CondInt;
+      E = VerifyIntegerConstantExpression(
+          E.get(), &CondInt,
+          // TODO: have our own diagnostic
+          diag::err_constexpr_if_condition_expression_is_not_constant);
+      if (E.isInvalid()) {
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cjappl wrote:

Minor funky 4 spacing for the first few lines here

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