[mono][interp] Preserve type information of stack args when inlining (#86898)

In order to enable more devirtualization. Type information from caller method should always be more specific (or the same) as the one coming from inlined method signature.

diff --git a/src/mono/mono/mini/interp/transform.c b/src/mono/mono/mini/interp/transform.c
index da8c564..e3f938a 100644 (file)
--- a/src/mono/mono/mini/interp/transform.c
+++ b/src/mono/mono/mini/interp/transform.c
@@ -4930,7 +4930,8 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
                arg_locals = (guint32*) g_malloc ((!!signature->hasthis + signature->param_count) * sizeof (guint32));
                /* Allocate locals to store inlined method args from stack */
                for (int i = signature->param_count - 1; i >= 0; i--) {
-                       local = create_interp_local (td, signature->params [i]);
+                       MonoType *type = td->locals [td->sp [-1].local].type;
+                       local = create_interp_local (td, type);
                        arg_locals [i + !!signature->hasthis] = local;
                        store_local (td, local);
                }
@@ -4940,11 +4941,7 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
                         * If this is value type, it is passed by address and not by value.
                         * Valuetype this local gets integer type MINT_TYPE_I.
                         */
-                       MonoType *type;
-                       if (m_class_is_valuetype (method->klass))
-                               type = mono_get_int_type ();
-                       else
-                               type = mono_get_object_type ();
+                       MonoType *type = td->locals [td->sp [-1].local].type;
                        local = create_interp_local (td, type);
                        arg_locals [0] = local;
                        store_local (td, local);