diff --git a/gc.c b/gc.c
index 4fc338015d..4a06047e9e 100644
--- a/gc.c
+++ b/gc.c
@@ -3745,6 +3745,7 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
           case imemo_callinfo:
             {
                 const struct rb_callinfo * ci = ((const struct rb_callinfo *)obj);
+                rb_vm_ci_free(ci);
                 if (ci->kwarg) {
                     ((struct rb_callinfo_kwarg *)ci->kwarg)->references--;
                     if (ci->kwarg->references == 0) xfree((void *)ci->kwarg);
diff --git a/internal/class.h b/internal/class.h
index fcdface028..74ad956e3e 100644
--- a/internal/class.h
+++ b/internal/class.h
@@ -44,7 +44,7 @@ struct rb_classext_struct {
     VALUE *iv_ptr;
     struct rb_id_table *const_tbl;
     struct rb_id_table *callable_m_tbl;
-    struct rb_id_table *cc_tbl; /* ID -> [[ci, cc1], cc2, ...] */
+    struct rb_id_table *cc_tbl; /* ID -> [[ci1, cc1], [ci2, cc2] ...] */
     struct rb_id_table *cvc_tbl;
     size_t superclass_depth;
     VALUE *superclasses;
diff --git a/vm.c b/vm.c
index 4f0e684bae..9c112d039b 100644
--- a/vm.c
+++ b/vm.c
@@ -2873,6 +2873,7 @@ rb_vm_update_references(void *ptr)
     if (ptr) {
         rb_vm_t *vm = ptr;
 
+        rb_gc_update_tbl_refs(vm->ci_table);
         rb_gc_update_tbl_refs(vm->frozen_strings);
         vm->mark_object_ary = rb_gc_location(vm->mark_object_ary);
         vm->load_path = rb_gc_location(vm->load_path);
@@ -3119,6 +3120,10 @@ ruby_vm_destruct(rb_vm_t *vm)
             st_free_table(vm->loading_table);
             vm->loading_table = 0;
         }
+        if (vm->ci_table) {
+            st_free_table(vm->ci_table);
+            vm->ci_table = NULL;
+        }
         if (vm->frozen_strings) {
             st_free_table(vm->frozen_strings);
             vm->frozen_strings = 0;
@@ -3209,6 +3214,7 @@ vm_memsize(const void *ptr)
         rb_vm_memsize_workqueue(&vm->workqueue) +
         rb_st_memsize(vm->defined_module_hash) +
         vm_memsize_at_exit_list(vm->at_exit) +
+        rb_st_memsize(vm->ci_table) +
         rb_st_memsize(vm->frozen_strings) +
         vm_memsize_builtin_function_table(vm->builtin_function_table) +
         rb_id_table_memsize(vm->negative_cme_table) +
@@ -4303,6 +4309,7 @@ Init_vm_objects(void)
     /* initialize mark object array, hash */
     vm->mark_object_ary = rb_ary_hidden_new(128);
     vm->loading_table = st_init_strtable();
+    vm->ci_table = st_init_table(&vm_ci_hashtype);
     vm->frozen_strings = st_init_table_with_size(&rb_fstring_hash_type, 10000);
 }
 
diff --git a/vm_callinfo.h b/vm_callinfo.h
index 2165582a2f..8b45d7fdf3 100644
--- a/vm_callinfo.h
+++ b/vm_callinfo.h
@@ -199,12 +199,13 @@ vm_ci_dump(const struct rb_callinfo *ci)
       (((VALUE)(argc)) << CI_EMBED_ARGC_SHFT) |  \
       RUBY_FIXNUM_FLAG))
 
+// vm_method.c
+const struct rb_callinfo *rb_vm_ci_lookup(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg);
+void rb_vm_ci_free(const struct rb_callinfo *);
+
 static inline const struct rb_callinfo *
 vm_ci_new_(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg, const char *file, int line)
 {
-    if (kwarg) {
-        ((struct rb_callinfo_kwarg *)kwarg)->references++;
-    }
     if (USE_EMBED_CI && VM_CI_EMBEDDABLE_P(mid, flag, argc, kwarg)) {
         RB_DEBUG_COUNTER_INC(ci_packed);
         return vm_ci_new_id(mid, flag, argc, kwarg);
@@ -213,13 +214,7 @@ vm_ci_new_(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinf
     const bool debug = 0;
     if (debug) ruby_debug_printf("%s:%d ", file, line);
 
-    // TODO: dedup
-    const struct rb_callinfo *ci = (const struct rb_callinfo *)
-      rb_imemo_new(imemo_callinfo,
-                   (VALUE)mid,
-                   (VALUE)flag,
-                   (VALUE)argc,
-                   (VALUE)kwarg);
+    const struct rb_callinfo *ci = rb_vm_ci_lookup(mid, flag, argc, kwarg);
     if (debug) rp(ci);
     if (kwarg) {
         RB_DEBUG_COUNTER_INC(ci_kw);
diff --git a/vm_core.h b/vm_core.h
index 448e17ba52..8889ed7c31 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -752,6 +752,7 @@ typedef struct rb_vm_struct {
 
     const struct rb_builtin_function *builtin_function_table;
 
+    st_table *ci_table;
     struct rb_id_table *negative_cme_table;
     st_table *overloaded_cme_table; // cme -> overloaded_cme
 
diff --git a/vm_method.c b/vm_method.c
index ffc99ff76c..bd43d7ea4d 100644
--- a/vm_method.c
+++ b/vm_method.c
@@ -333,6 +333,120 @@ invalidate_all_refinement_cc(void *vstart, void *vend, size_t stride, void *data
     return 0; // continue to iteration
 }
 
+static st_index_t
+vm_ci_hash(VALUE v)
+{
+    const struct rb_callinfo *ci = (const struct rb_callinfo *)v;
+    st_index_t h;
+    h = rb_hash_start(ci->mid);
+    h = rb_hash_uint(h, ci->flag);
+    h = rb_hash_uint(h, ci->argc);
+    if (ci->kwarg) {
+        for (int i = 0; i < ci->kwarg->keyword_len; i++) {
+            h = rb_hash_uint(h, ci->kwarg->keywords[i]);
+        }
+    }
+    return h;
+}
+
+static int
+vm_ci_hash_cmp(VALUE v1, VALUE v2)
+{
+    const struct rb_callinfo *ci1 = (const struct rb_callinfo *)v1;
+    const struct rb_callinfo *ci2 = (const struct rb_callinfo *)v2;
+    if (ci1->mid != ci2->mid) return 1;
+    if (ci1->flag != ci2->flag) return 1;
+    if (ci1->argc != ci2->argc) return 1;
+    if (ci1->kwarg != NULL) {
+        VM_ASSERT(ci2->kwarg != NULL); // implied by matching flags
+
+        if (ci1->kwarg->keyword_len != ci2->kwarg->keyword_len)
+            return 1;
+
+        for (int i = 0; i < ci1->kwarg->keyword_len; i++) {
+            if (ci1->kwarg->keywords[i] != ci2->kwarg->keywords[i]) {
+                return 1;
+            }
+        }
+    } else {
+        VM_ASSERT(ci2->kwarg == NULL); // implied by matching flags
+    }
+    return 0;
+}
+
+static const struct st_hash_type vm_ci_hashtype = {
+    vm_ci_hash_cmp,
+    vm_ci_hash
+};
+
+static int
+ci_lookup_i(st_data_t *key, st_data_t *value, st_data_t data, int existing)
+{
+    const struct rb_callinfo *ci = (const struct rb_callinfo *)*key;
+    st_data_t *ret = (st_data_t *)data;
+
+    if (existing) {
+        if (rb_objspace_garbage_object_p((VALUE)ci)) {
+            *ret = (st_data_t)NULL;
+            return ST_DELETE;
+        } else {
+            *ret = *key;
+            return ST_STOP;
+        }
+    }
+    else {
+        *key = *value = *ret = (st_data_t)ci;
+        return ST_CONTINUE;
+    }
+}
+
+const struct rb_callinfo *
+rb_vm_ci_lookup(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg)
+{
+    rb_vm_t *vm = GET_VM();
+    const struct rb_callinfo *ci = NULL;
+
+    if (kwarg) {
+        ((struct rb_callinfo_kwarg *)kwarg)->references++;
+    }
+    const struct rb_callinfo *new_ci = (const struct rb_callinfo *)
+        rb_imemo_new(
+                imemo_callinfo,
+                (VALUE)mid,
+                (VALUE)flag,
+                (VALUE)argc,
+                (VALUE)kwarg);
+
+    RB_VM_LOCK_ENTER();
+    {
+        st_table *ci_table = vm->ci_table;
+        VM_ASSERT(ci_table);
+
+        do {
+            st_update(ci_table, (st_data_t)new_ci, ci_lookup_i, (st_data_t)&ci);
+        } while (ci == NULL);
+    }
+    RB_VM_LOCK_LEAVE();
+
+    VM_ASSERT(ci);
+    VM_ASSERT(vm_ci_markable(ci));
+
+    return ci;
+}
+
+void
+rb_vm_ci_free(const struct rb_callinfo *ci)
+{
+    rb_vm_t *vm = GET_VM();
+
+    RB_VM_LOCK_ENTER();
+    {
+        st_data_t key = (st_data_t)ci;
+        st_delete(vm->ci_table, &key, NULL);
+    }
+    RB_VM_LOCK_LEAVE();
+}
+
 void
 rb_clear_all_refinement_method_cache(void)
 {