[clang] [Clang][C++23] Implement P1774R8: Portable assumptions (PR #81014)

[Erich Keane via cfe-commits]

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@@ -1996,6 +1996,30 @@ Here is an example:
   }];
 }
 
+def AssumeDocs : Documentation {
+  let Category = DocCatStmt;
+  let Heading = "assume";
+  let Content = [{
+The ``assume`` attribute is used to indicate to the optimizer that a
+certain condition can be assumed to be true at a certain point in the
+program. If this condition is violated at runtime, the behavior is
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erichkeane wrote:

It came from memory of the discussion in EWG, though I note that the paper is actually pretty confusing about this, it calls it both 'not evaluated' (https://eel.is/c++draft/dcl.attr.assume#sentence-3) AND 'potentially evaluated' : https://eel.is/c++draft/dcl.attr.assume#sentence-6.

So I'm not sure actually...


https://github.com/llvm/llvm-project/pull/81014