_apply_in_world builtin

New builtin Core._apply_in_world to allow frozen-world APIs to be
implemented in pure Julia code.

Author: c42f

src/builtin_proto.h

@@ -24,6 +24,7 @@ DECLARE_BUILTIN(typeof);     DECLARE_BUILTIN(sizeof);
 DECLARE_BUILTIN(issubtype);  DECLARE_BUILTIN(isa);
 DECLARE_BUILTIN(_apply);     DECLARE_BUILTIN(_apply_pure);
 DECLARE_BUILTIN(_apply_latest); DECLARE_BUILTIN(_apply_iterate);
+DECLARE_BUILTIN(_apply_in_world);
 DECLARE_BUILTIN(isdefined);  DECLARE_BUILTIN(nfields);
 DECLARE_BUILTIN(tuple);      DECLARE_BUILTIN(svec);
 DECLARE_BUILTIN(getfield);   DECLARE_BUILTIN(setfield);

src/builtins.c

@@ -707,6 +707,24 @@ JL_CALLABLE(jl_f__apply_latest)
     return ret;
 }
 
+// Like `_apply`, but runs in the specified world.
+// If world > jl_world_counter, run in the latest world.
+JL_CALLABLE(jl_f__apply_in_world)
+{
+    JL_NARGSV(_apply_in_world, 2);
+    jl_ptls_t ptls = jl_get_ptls_states();
+    size_t last_age = ptls->world_age;
+    JL_TYPECHK(_apply_in_world, ulong, args[0]);
+    size_t world = jl_unbox_ulong(args[0]);
+    world = world <= jl_world_counter ? world : jl_world_counter;
+    if (!ptls->in_pure_callback) {
+        ptls->world_age = world;
+    }
+    jl_value_t *ret = do_apply(NULL, args+1, nargs-1, NULL);
+    ptls->world_age = last_age;
+    return ret;
+}
+
 // tuples ---------------------------------------------------------------------
 
 JL_CALLABLE(jl_f_tuple)
@@ -1529,6 +1547,7 @@ void jl_init_primitives(void) JL_GC_DISABLED
     jl_builtin_svec = add_builtin_func("svec", jl_f_svec);
     add_builtin_func("_apply_pure", jl_f__apply_pure);
     add_builtin_func("_apply_latest", jl_f__apply_latest);
+    add_builtin_func("_apply_in_world", jl_f__apply_in_world);
     add_builtin_func("_typevar", jl_f__typevar);
     add_builtin_func("_structtype", jl_f__structtype);
     add_builtin_func("_abstracttype", jl_f__abstracttype);

src/codegen.cpp

@@ -7018,6 +7018,7 @@ static void init_julia_llvm_env(Module *m)
     builtin_func_map[jl_f__apply_iterate] = jlcall_func_to_llvm("jl_f__apply_iterate", &jl_f__apply_iterate, m);
     builtin_func_map[jl_f__apply_pure] = jlcall_func_to_llvm("jl_f__apply_pure", &jl_f__apply_pure, m);
     builtin_func_map[jl_f__apply_latest] = jlcall_func_to_llvm("jl_f__apply_latest", &jl_f__apply_latest, m);
+    builtin_func_map[jl_f__apply_in_world] = jlcall_func_to_llvm("jl_f__apply_in_world", &jl_f__apply_in_world, m);
     builtin_func_map[jl_f_throw] = jlcall_func_to_llvm("jl_f_throw", &jl_f_throw, m);
     builtin_func_map[jl_f_tuple] = jlcall_func_to_llvm("jl_f_tuple", &jl_f_tuple, m);
     builtin_func_map[jl_f_svec] = jlcall_func_to_llvm("jl_f_svec", &jl_f_svec, m);

src/julia.h

@@ -1312,6 +1312,7 @@ JL_DLLEXPORT int jl_get_size(jl_value_t *val, size_t *pnt);
 #define jl_unbox_long(x) jl_unbox_int64(x)
 #define jl_unbox_ulong(x) jl_unbox_uint64(x)
 #define jl_is_long(x)    jl_is_int64(x)
+#define jl_is_ulong(x)   jl_is_uint64(x)
 #define jl_long_type     jl_int64_type
 #define jl_ulong_type    jl_uint64_type
 #else
@@ -1320,6 +1321,7 @@ JL_DLLEXPORT int jl_get_size(jl_value_t *val, size_t *pnt);
 #define jl_unbox_long(x) jl_unbox_int32(x)
 #define jl_unbox_ulong(x) jl_unbox_uint32(x)
 #define jl_is_long(x)    jl_is_int32(x)
+#define jl_is_ulong(x)   jl_is_uint32(x)
 #define jl_long_type     jl_int32_type
 #define jl_ulong_type    jl_uint32_type
 #endif

src/staticdata.c

@@ -117,7 +117,8 @@ void *native_functions;
 // This is a manually constructed dual of the fvars array, which would be produced by codegen for Julia code, for C.
 static const jl_fptr_args_t id_to_fptrs[] = {
     &jl_f_throw, &jl_f_is, &jl_f_typeof, &jl_f_issubtype, &jl_f_isa,
-    &jl_f_typeassert, &jl_f__apply, &jl_f__apply_iterate, &jl_f__apply_pure, &jl_f__apply_latest, &jl_f_isdefined,
+    &jl_f_typeassert, &jl_f__apply, &jl_f__apply_iterate, &jl_f__apply_pure,
+    &jl_f__apply_latest, &jl_f__apply_in_world, &jl_f_isdefined,
     &jl_f_tuple, &jl_f_svec, &jl_f_intrinsic_call, &jl_f_invoke_kwsorter,
     &jl_f_getfield, &jl_f_setfield, &jl_f_fieldtype, &jl_f_nfields,
     &jl_f_arrayref, &jl_f_const_arrayref, &jl_f_arrayset, &jl_f_arraysize, &jl_f_apply_type,

test/worlds.jl

@@ -199,3 +199,11 @@ end
 notify(c26506_1)
 wait(c26506_2)
 @test result26506[1] == 3
+
+# _apply_in_world builtin
+f_aiw(x) = "world one; x=$x"
+wc_aiw1 = get_world_counter()
+f_aiw(x) = "world two; x=$x"
+wc_aiw2 = get_world_counter()
+@test Core._apply_in_world(wc_aiw1, f_aiw, (2,)) == "world one; x=2"
+@test Core._apply_in_world(wc_aiw2, f_aiw, (2,)) == "world two; x=2"