try working around broken subtyping in known_isa codegen optimization

JuliaLang · Jul 6, 2018 · b134664 · b134664
1 parent 559090a
commit b134664
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Showing 3 changed files with 10 additions and 2 deletions.
diff --git a/src/cgutils.cpp b/src/cgutils.cpp
@@ -1069,8 +1069,8 @@ static std::pair<Value*, bool> emit_isa(jl_codectx_t &ctx, const jl_cgval_t &x,
     jl_value_t *intersected_type = type;
     if (x.constant)
         known_isa = jl_isa(x.constant, type);
-    else if (jl_subtype(x.typ, type)) {
-        // known_isa = true;
+    else if (jl_is_not_broken_subtype(x.typ, type) && jl_subtype(x.typ, type)) {
+        known_isa = true;
     } else {
         intersected_type = jl_type_intersection(x.typ, type);
         if (intersected_type == (jl_value_t*)jl_bottom_type)

diff --git a/src/julia.h b/src/julia.h
@@ -1067,6 +1067,7 @@ JL_DLLEXPORT int jl_subtype_env_size(jl_value_t *t);
 JL_DLLEXPORT int jl_subtype_env(jl_value_t *x, jl_value_t *y, jl_value_t **env, int envsz);
 JL_DLLEXPORT int jl_isa(jl_value_t *a, jl_value_t *t);
 JL_DLLEXPORT int jl_types_equal(jl_value_t *a, jl_value_t *b) JL_NOTSAFEPOINT;
+JL_DLLEXPORT int jl_is_not_broken_subtype(jl_value_t *a, jl_value_t *b);
 JL_DLLEXPORT jl_value_t *jl_type_union(jl_value_t **ts, size_t n);
 JL_DLLEXPORT jl_value_t *jl_type_intersection(jl_value_t *a, jl_value_t *b);
 JL_DLLEXPORT int jl_has_empty_intersection(jl_value_t *x, jl_value_t *y);

diff --git a/src/subtype.c b/src/subtype.c
@@ -1165,6 +1165,13 @@ JL_DLLEXPORT int jl_types_equal(jl_value_t *a, jl_value_t *b)
     return jl_subtype(a, b) && jl_subtype(b, a);
 }
 
+JL_DLLEXPORT int jl_is_not_broken_subtype(jl_value_t *a, jl_value_t *b)
+{
+    // TODO: the final commented out check here isn't correct; it should be closer to the
+    // `issingletype` check used by `isnotbrokensubtype` in `base/compiler/typeutils.jl`
+    return !jl_is_kind(b) || !jl_is_type_type(a); // || jl_is_datatype_singleton((jl_datatype_t*)jl_tparam0(a));
+}
+
 int jl_tuple_isa(jl_value_t **child, size_t cl, jl_datatype_t *pdt)
 {
     if (jl_is_tuple_type(pdt) && !jl_is_va_tuple(pdt)) {