Add Base.isprecompilable

base/loading.jl

@@ -4187,6 +4187,20 @@ function expand_compiler_path(tup)
 end
 compiler_chi(tup::Tuple) = CacheHeaderIncludes(expand_compiler_path(tup))
 
+"""
+    isprecompilable(f, argtypes::Tuple{Vararg{Any}})
+
+Check, as far as is possible without actually compiling, if the given
+function `f` can be compiled for the argument tuple (of types) `argtypes`.
+"""
+function isprecompilable(@nospecialize(f), @nospecialize(argtypes::Tuple))
+    isprecompilable(Tuple{Core.Typeof(f), argtypes...})
+end
+
+function isprecompilable(@nospecialize(argt::Type))
+    ccall(:jl_is_compilable, Int32, (Any,), argt) != 0
+end
+
 """
     precompile(f, argtypes::Tuple{Vararg{Any}})
 

src/gf.c

@@ -3579,6 +3579,15 @@ JL_DLLEXPORT void jl_compile_method_sig(jl_method_t *m, jl_value_t *types, jl_sv
     jl_compile_method_instance(mi, NULL, world);
 }
 
+JL_DLLEXPORT int jl_is_compilable(jl_tupletype_t *types)
+{
+    size_t world = jl_atomic_load_acquire(&jl_world_counter);
+    size_t min_valid = 0;
+    size_t max_valid = ~(size_t)0;
+    jl_method_instance_t *mi = jl_get_compile_hint_specialization(types, world, &min_valid, &max_valid, 1);
+    return mi == NULL ? 0 : 1;
+}
+
 JL_DLLEXPORT int jl_compile_hint(jl_tupletype_t *types)
 {
     size_t world = jl_atomic_load_acquire(&jl_world_counter);

src/jl_exported_funcs.inc

@@ -264,6 +264,7 @@
     XX(jl_istopmod) \
     XX(jl_is_binding_deprecated) \
     XX(jl_is_char_signed) \
+    XX(jl_is_compilable) \
     XX(jl_is_const) \
     XX(jl_is_assertsbuild) \
     XX(jl_is_debugbuild) \