kit

commit 2d37ba7b367e02cf86618cfa9e3a7a92d516e7ea
parent b9d9f14016146421df4aad8dc36cb35279db6258
Author: Ryan Sepassi <rsepassi@gmail.com>
Date:   Wed,  3 Jun 2026 12:12:29 -0700

cg: restore out-of-range fallback in intrinsic table accessors

The four KitCgIntrinsic accessors index kIntrinTable directly; route them
through a bounds-guarded intrin_desc() so an out-of-range value falls back to
the NONE row, matching the defensive default: arms the switches carried before
the table collapse. (Equivalence-review nit; valid enum inputs unaffected.)

Diffstat:
M
src/cg/arith.c
 | 
18
++++++++++++++----

1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/src/cg/arith.c b/src/cg/arith.c
@@ -895,25 +895,35 @@ _Static_assert(sizeof(kIntrinTable) / sizeof(kIntrinTable[0]) ==
                    KIT_CG_INTRIN_CORO_SWITCH + 1,
                "kIntrinTable must have exactly one row per KitCgIntrinsic");
 
+/* Bounds-guarded row lookup: an out-of-range intrinsic falls back to the NONE
+ * row, preserving the defensive `default:` behavior the four switches carried
+ * before they collapsed into kIntrinTable. */
+static const IntrinDesc* intrin_desc(KitCgIntrinsic intrin) {
+  static const IntrinDesc none = {INTRIN_NONE, NULL, false, false};
+  unsigned i = (unsigned)intrin;
+  return i < sizeof(kIntrinTable) / sizeof(kIntrinTable[0]) ? &kIntrinTable[i]
+                                                            : &none;
+}
+
 IntrinKind api_map_intrinsic(KitCg* g, KitCgIntrinsic intrin,
                              KitCgTypeId result_type) {
   /* Width-by-type: backends derive operand width from the result type, so the
    * mapping no longer needs the size here. */
   (void)g;
   (void)result_type;
-  return kIntrinTable[intrin].kind;
+  return intrin_desc(intrin)->kind;
 }
 
 int api_intrinsic_is_void(KitCgIntrinsic intrin) {
-  return kIntrinTable[intrin].is_void;
+  return intrin_desc(intrin)->is_void;
 }
 
 int api_intrinsic_is_overflow(KitCgIntrinsic intrin) {
-  return kIntrinTable[intrin].is_overflow;
+  return intrin_desc(intrin)->is_overflow;
 }
 
 const char* api_intrinsic_name(KitCgIntrinsic intrin) {
-  const char* name = kIntrinTable[intrin].name;
+  const char* name = intrin_desc(intrin)->name;
   return name ? name : "intrinsic";
 }