Allow opting out of PartialOpaque support via Expr(:opaque_closure, ...) (#55068)

This can be useful for when an OpaqueClosure is desired, e.g., as an
invalidation barrier or when you know it passes through an inference
barrier naturally (in my case, a mutable type).

This is intentionally left undocumented for now.

Author: topolarity

base/opaque_closure.jl

@@ -18,7 +18,7 @@ the argument type may be fixed length even if the function is variadic.
     This interface is experimental and subject to change or removal without notice.
 """
 macro opaque(ex)
-    esc(Expr(:opaque_closure, nothing, nothing, nothing, ex))
+    esc(Expr(:opaque_closure, nothing, nothing, nothing, #= allow_partial =# true, ex))
 end
 
 macro opaque(ty, ex)
@@ -34,7 +34,7 @@ macro opaque(ty, ex)
     end
     AT = (AT !== :_) ? AT : nothing
     RT = (RT !== :_) ? RT : nothing
-    return esc(Expr(:opaque_closure, AT, RT, RT, ex))
+    return esc(Expr(:opaque_closure, AT, RT, RT, #= allow_partial =# true, ex))
 end
 
 # OpaqueClosure construction from pre-inferred CodeInfo/IRCode

src/julia-syntax.scm

@@ -2435,7 +2435,8 @@
      (let* ((argt  (something (list (expand-forms (cadr e)) #f)))
             (rt_lb (something (list (expand-forms (caddr e)) #f)))
             (rt_ub (something (list (expand-forms (cadddr e)) #f)))
-            (F     (caddddr e))
+            (allow-partial (caddddr e))
+            (F             (cadddddr e))
             (isva (let* ((arglist (function-arglist F))
                          (lastarg (and (pair? arglist) (last arglist))))
                     (if (and argt (any (lambda (arg)
@@ -2460,7 +2461,7 @@
        (let* ((argtype   (foldl (lambda (var ex) `(call (core UnionAll) ,var ,ex))
                                 (expand-forms `(curly (core Tuple) ,@argtypes))
                                 (reverse tvars))))
-         `(_opaque_closure ,(or argt argtype) ,rt_lb ,rt_ub ,isva ,(length argtypes) ,functionloc ,lam))))
+         `(_opaque_closure ,(or argt argtype) ,rt_lb ,rt_ub ,isva ,(length argtypes) ,allow-partial ,functionloc ,lam))))
 
    'block
    (lambda (e)
@@ -4028,7 +4029,8 @@ f(x) = yt(x)
           ((_opaque_closure)
            (let* ((isva  (car (cddddr e)))
                   (nargs (cadr (cddddr e)))
-                  (functionloc (caddr (cddddr e)))
+                  (allow-partial (caddr (cddddr e)))
+                  (functionloc   (cadddr (cddddr e)))
                   (lam2  (last e))
                   (vis   (lam:vinfo lam2))
                   (cvs   (map car (cadr vis))))
@@ -4040,7 +4042,7 @@ f(x) = yt(x)
                                            v)))
                                    cvs)))
                `(new_opaque_closure
-                 ,(cadr e) ,(or (caddr e) '(call (core apply_type) (core Union))) ,(or (cadddr e) '(core Any)) (true)
+                 ,(cadr e) ,(or (caddr e) '(call (core apply_type) (core Union))) ,(or (cadddr e) '(core Any)) ,allow-partial
                  (opaque_closure_method (null) ,nargs ,isva ,functionloc ,(convert-lambda lam2 (car (lam:args lam2)) #f '() (symbol-to-idx-map cvs)))
                  ,@var-exprs))))
           ((method)

test/precompile.jl

@@ -2012,6 +2012,13 @@ precompile_test_harness("Generated Opaque") do load_path
                 Expr(:opaque_closure_method, nothing, 0, false, lno, ci))
         end
         @assert oc_re_generated_no_partial()() === 1
+        @generated function oc_re_generated_no_partial_macro()
+            AT = nothing
+            RT = nothing
+            allow_partial = false # makes this legal to generate during pre-compile
+            return Expr(:opaque_closure, AT, RT, RT, allow_partial, :(()->const_int_barrier()))
+        end
+        @assert oc_re_generated_no_partial_macro()() === 1
         end
         """)
     Base.compilecache(Base.PkgId("GeneratedOpaque"))