From c10b8fef1b7adaa97154ae545cc69f9fd23c8c7b Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 26 Jun 2024 19:34:06 -0600
Subject: [PATCH 01/30] Add 'Prim.componentCall()' for interacting with an
 external Wasm component

---
 src/codegen/compile.ml | 8 ++++++++
 src/prelude/prim.mo    | 2 ++
 2 files changed, 10 insertions(+)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index bbce0ee1646..e9acf6bd0c6 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11252,6 +11252,11 @@ and compile_prim_invocation (env : E.t) ae p es at =
     compile_exp_as env ae SR.UnboxedFloat64 e ^^
     E.call_import env "rts" "log" (* musl *)
 
+  | OtherPrim "componentCall", [e] ->
+    SR.UnboxedWord32 Type.Nat32,
+    compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
+    E.call_import env "component" "call"
+
   (* Other prims, nullary *)
 
   | SystemTimePrim, [] ->
@@ -12818,6 +12823,9 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
   IC.system_imports env;
   RTS.system_imports env;
 
+  (* Component model *)
+  E.add_func_import env "component" "call" [I32Type] [I32Type];
+
   compile_init_func env prog;
   let start_fi_o = match E.mode env with
     | Flags.ICMode | Flags.RefMode ->
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 27e2efa3783..45331d82d99 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -267,6 +267,8 @@ func arctan2(y : Float, x : Float) : Float = (prim "fatan2" : (Float, Float) ->
 func exp(f : Float) : Float = (prim "fexp" : Float -> Float) f;
 func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 
+func componentCall(n : Nat32) : Nat32 = (prim "componentCall" : Nat32 -> Nat32) n;
+
 // Array utilities
 
 func Array_init<T>(len : Nat, x : T) : [var T] {

From fe8b7f44f27dbff04b9dd331c825123dab901198 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 26 Jun 2024 19:57:09 -0600
Subject: [PATCH 02/30] Add '-import-component' flag

---
 src/codegen/compile.ml | 5 +++--
 src/exes/moc.ml        | 3 +++
 src/mo_config/flags.ml | 1 +
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index e9acf6bd0c6..a5edd3630c3 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11252,7 +11252,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
     compile_exp_as env ae SR.UnboxedFloat64 e ^^
     E.call_import env "rts" "log" (* musl *)
 
-  | OtherPrim "componentCall", [e] ->
+  | OtherPrim "componentCall", [e] when !Flags.import_component ->
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
     E.call_import env "component" "call"
@@ -12824,7 +12824,8 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
   RTS.system_imports env;
 
   (* Component model *)
-  E.add_func_import env "component" "call" [I32Type] [I32Type];
+  if !Flags.import_component then
+    E.add_func_import env "component" "call" [I32Type] [I32Type];
 
   compile_init_func env prog;
   let start_fi_o = match E.mode env with
diff --git a/src/exes/moc.ml b/src/exes/moc.ml
index 630778afd54..369ee1f80cd 100644
--- a/src/exes/moc.ml
+++ b/src/exes/moc.ml
@@ -109,6 +109,9 @@ let argspec = [
   "-wasi-system-api",
     Arg.Unit (fun () -> Flags.(compile_mode := WASIMode)),
       " use the WASI system API (wasmtime)";
+  "-import-component",
+    Arg.Unit (fun () -> Flags.(import_component := true)),
+      " enable calling an external Wasm component";
   "-ref-system-api",
   Arg.Unit (fun () -> Flags.(compile_mode := RefMode)),
       " use the reference implementation of the Internet Computer system API (ic-ref-run)";
diff --git a/src/mo_config/flags.ml b/src/mo_config/flags.ml
index 849dd30e7a0..033fbfbc0fe 100644
--- a/src/mo_config/flags.ml
+++ b/src/mo_config/flags.ml
@@ -50,3 +50,4 @@ let rtti = ref false
 let trap_on_call_error = ref false
 let use_stable_regions = ref false
 let share_code = ref false
+let import_component = ref false

From 163fb60237764e9b88f34a637ab1dd74da5a4aec Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 10:28:40 -0600
Subject: [PATCH 03/30] Add M0200 error message ('component import is
 unavailable')

---
 src/codegen/compile.ml              | 16 +++++++++++-----
 src/lang_utils/error_codes.ml       |  1 +
 src/lang_utils/error_codes/M0200.md |  5 +++++
 src/prelude/prim.mo                 |  2 ++
 4 files changed, 19 insertions(+), 5 deletions(-)
 create mode 100644 src/lang_utils/error_codes/M0200.md

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index a5edd3630c3..9450410c165 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11252,10 +11252,16 @@ and compile_prim_invocation (env : E.t) ae p es at =
     compile_exp_as env ae SR.UnboxedFloat64 e ^^
     E.call_import env "rts" "log" (* musl *)
 
-  | OtherPrim "componentCall", [e] when !Flags.import_component ->
-    SR.UnboxedWord32 Type.Nat32,
-    compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
-    E.call_import env "component" "call"
+  | OtherPrim "componentCall", [e] ->
+    if !Flags.import_component then
+      SR.UnboxedWord32 Type.Nat32,
+      compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
+      E.call_import env "component" "call"
+    else
+      (* TODO: type checking error? *)
+      Printf.printf "%s" (Diag.string_of_message (
+        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable" s')));
+      exit 1)
 
   (* Other prims, nullary *)
 
@@ -12823,7 +12829,7 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
   IC.system_imports env;
   RTS.system_imports env;
 
-  (* Component model *)
+  (* Wasm component model *)
   if !Flags.import_component then
     E.add_func_import env "component" "call" [I32Type] [I32Type];
 
diff --git a/src/lang_utils/error_codes.ml b/src/lang_utils/error_codes.ml
index 15158cb264a..9d78667952b 100644
--- a/src/lang_utils/error_codes.ml
+++ b/src/lang_utils/error_codes.ml
@@ -203,4 +203,5 @@ let error_codes : (string * string option) list =
     "M0197", Some([%blob "lang_utils/error_codes/M0197.md"]); (* `system` capability required *)
     "M0198", Some([%blob "lang_utils/error_codes/M0198.md"]); (* Unused field pattern warning *)
     "M0199", Some([%blob "lang_utils/error_codes/M0199.md"]); (* Deprecate experimental stable memory *)
+    "M0200", Some([%blob "lang_utils/error_codes/M0200.md"]); (* Component import is unavailable *)
   ]
diff --git a/src/lang_utils/error_codes/M0200.md b/src/lang_utils/error_codes/M0200.md
new file mode 100644
index 00000000000..09e040ac8f3
--- /dev/null
+++ b/src/lang_utils/error_codes/M0200.md
@@ -0,0 +1,5 @@
+# M0200
+
+This error indicates that the Wasm component model (cross-language) functionality is not enabled. 
+
+You can fix this by passing the `-import-component` compiler flag, e.g. `moc -wasi-system-api -import-component ...`.
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index b03cf339491..cd9e11e853b 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -267,6 +267,8 @@ func arctan2(y : Float, x : Float) : Float = (prim "fatan2" : (Float, Float) ->
 func exp(f : Float) : Float = (prim "fexp" : Float -> Float) f;
 func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 
+// Wasm component model functions
+
 func componentCall(n : Nat32) : Nat32 = (prim "componentCall" : Nat32 -> Nat32) n;
 
 // Array utilities

From 8c113053baf96853047d8a056977447fa7836b06 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 10:39:28 -0600
Subject: [PATCH 04/30] Fix compile error

---
 src/codegen/compile.ml | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 9450410c165..e624580ad9d 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11253,15 +11253,13 @@ and compile_prim_invocation (env : E.t) ae p es at =
     E.call_import env "rts" "log" (* musl *)
 
   | OtherPrim "componentCall", [e] ->
-    if !Flags.import_component then
-      SR.UnboxedWord32 Type.Nat32,
-      compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
-      E.call_import env "component" "call"
-    else
-      (* TODO: type checking error? *)
+    if not !Flags.import_component then (
       Printf.printf "%s" (Diag.string_of_message (
-        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable" s')));
-      exit 1)
+        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable")));
+      exit 1);
+    SR.UnboxedWord32 Type.Nat32,
+    compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
+    E.call_import env "component" "call"
 
   (* Other prims, nullary *)
 

From d729cd59e1692ecd894ea7d32adca18cfd08e76b Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 11:28:12 -0600
Subject: [PATCH 05/30] Add test

---
 src/codegen/compile.ml                  | 2 +-
 test/fail/import-component.mo           | 5 +++++
 test/fail/ok/import-component.tc.ok     | 1 +
 test/fail/ok/import-component.tc.ret.ok | 1 +
 4 files changed, 8 insertions(+), 1 deletion(-)
 create mode 100644 test/fail/import-component.mo
 create mode 100644 test/fail/ok/import-component.tc.ok
 create mode 100644 test/fail/ok/import-component.tc.ret.ok

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index e624580ad9d..c2b47fba3ca 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11255,7 +11255,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
   | OtherPrim "componentCall", [e] ->
     if not !Flags.import_component then (
       Printf.printf "%s" (Diag.string_of_message (
-        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable")));
+        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
       exit 1);
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
diff --git a/test/fail/import-component.mo b/test/fail/import-component.mo
new file mode 100644
index 00000000000..64ef04e7b0f
--- /dev/null
+++ b/test/fail/import-component.mo
@@ -0,0 +1,5 @@
+import P = "mo:⛔";
+
+ignore P.callComponent(123);
+
+assert false;
diff --git a/test/fail/ok/import-component.tc.ok b/test/fail/ok/import-component.tc.ok
new file mode 100644
index 00000000000..d0dbac1113e
--- /dev/null
+++ b/test/fail/ok/import-component.tc.ok
@@ -0,0 +1 @@
+import-component.mo:3.8-3.28: RTS error [M0199], component import is unavailable (pass `-import-component` flag)
diff --git a/test/fail/ok/import-component.tc.ret.ok b/test/fail/ok/import-component.tc.ret.ok
new file mode 100644
index 00000000000..69becfa16f9
--- /dev/null
+++ b/test/fail/ok/import-component.tc.ret.ok
@@ -0,0 +1 @@
+Return code 1

From 36b92cf16af6abc550bdb92319322e7d71cc8219 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 11:32:53 -0600
Subject: [PATCH 06/30] Adjust error code in error message

---
 src/codegen/compile.ml              | 2 +-
 test/fail/ok/import-component.tc.ok | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index c2b47fba3ca..30b42b4cd91 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11255,7 +11255,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
   | OtherPrim "componentCall", [e] ->
     if not !Flags.import_component then (
       Printf.printf "%s" (Diag.string_of_message (
-        Diag.error_message at "M0199" "RTS" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
+        Diag.error_message at "M0200" "RTS" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
       exit 1);
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
diff --git a/test/fail/ok/import-component.tc.ok b/test/fail/ok/import-component.tc.ok
index d0dbac1113e..c82dcd1af14 100644
--- a/test/fail/ok/import-component.tc.ok
+++ b/test/fail/ok/import-component.tc.ok
@@ -1 +1 @@
-import-component.mo:3.8-3.28: RTS error [M0199], component import is unavailable (pass `-import-component` flag)
+import-component.mo:3.8-3.28: RTS error [M0200], component import is unavailable (pass `-import-component` flag)

From 330a295aee0ce817c1da765906892a9e3fa04ceb Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 12:44:19 -0600
Subject: [PATCH 07/30] Fix

---
 test/fail/import-component.mo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/fail/import-component.mo b/test/fail/import-component.mo
index 64ef04e7b0f..be06d273812 100644
--- a/test/fail/import-component.mo
+++ b/test/fail/import-component.mo
@@ -1,5 +1,5 @@
 import P = "mo:⛔";
 
-ignore P.callComponent(123);
+ignore P.componentCall(123);
 
 assert false;

From 88744317512bacbc4fa0522dbbe2abd0587f9066 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 13:50:39 -0600
Subject: [PATCH 08/30] Rename test

---
 test/fail/{import-component.mo => M0200.mo}                  | 0
 test/fail/ok/{import-component.tc.ok => M0200.tc.ok}         | 0
 test/fail/ok/{import-component.tc.ret.ok => M0200.tc.ret.ok} | 0
 3 files changed, 0 insertions(+), 0 deletions(-)
 rename test/fail/{import-component.mo => M0200.mo} (100%)
 rename test/fail/ok/{import-component.tc.ok => M0200.tc.ok} (100%)
 rename test/fail/ok/{import-component.tc.ret.ok => M0200.tc.ret.ok} (100%)

diff --git a/test/fail/import-component.mo b/test/fail/M0200.mo
similarity index 100%
rename from test/fail/import-component.mo
rename to test/fail/M0200.mo
diff --git a/test/fail/ok/import-component.tc.ok b/test/fail/ok/M0200.tc.ok
similarity index 100%
rename from test/fail/ok/import-component.tc.ok
rename to test/fail/ok/M0200.tc.ok
diff --git a/test/fail/ok/import-component.tc.ret.ok b/test/fail/ok/M0200.tc.ret.ok
similarity index 100%
rename from test/fail/ok/import-component.tc.ret.ok
rename to test/fail/ok/M0200.tc.ret.ok

From 74c5809fd0bff3953c74dde52c2c423722b3c0b8 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 13:54:04 -0600
Subject: [PATCH 09/30] Adjust error message

---
 src/codegen/compile.ml   | 2 +-
 test/fail/ok/M0200.tc.ok | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 30b42b4cd91..3eb1d64df7e 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11255,7 +11255,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
   | OtherPrim "componentCall", [e] ->
     if not !Flags.import_component then (
       Printf.printf "%s" (Diag.string_of_message (
-        Diag.error_message at "M0200" "RTS" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
+        Diag.error_message at "M0200" "import" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
       exit 1);
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
diff --git a/test/fail/ok/M0200.tc.ok b/test/fail/ok/M0200.tc.ok
index c82dcd1af14..9d19d7d4ba0 100644
--- a/test/fail/ok/M0200.tc.ok
+++ b/test/fail/ok/M0200.tc.ok
@@ -1 +1 @@
-import-component.mo:3.8-3.28: RTS error [M0200], component import is unavailable (pass `-import-component` flag)
+M0200.mo:3.8-3.28: import error [M0200], component import is unavailable (pass `-import-component` flag)

From f4a63cb615b8d554966180847294b809be78ceca Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 15:19:47 -0600
Subject: [PATCH 10/30] Update test

---
 test/fail/M0200.mo | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/test/fail/M0200.mo b/test/fail/M0200.mo
index be06d273812..18934ac9828 100644
--- a/test/fail/M0200.mo
+++ b/test/fail/M0200.mo
@@ -1,5 +1,3 @@
-import P = "mo:⛔";
+import Prim = "mo:⛔";
 
-ignore P.componentCall(123);
-
-assert false;
+ignore Prim.componentCall(123);

From 90f73616bce585ef0bc0520c9fcd4b7d8fc3609b Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 27 Jun 2024 16:26:01 -0600
Subject: [PATCH 11/30] Misc

---
 src/codegen/compile.ml           | 2 +-
 test/fail/ok/M0200.tc.ok         | 1 -
 test/fail/ok/M0200.tc.ret.ok     | 1 -
 test/fail/ok/no-timer-canc.tc.ok | 1 +
 test/fail/ok/no-timer-set.tc.ok  | 1 +
 5 files changed, 3 insertions(+), 3 deletions(-)
 delete mode 100644 test/fail/ok/M0200.tc.ok
 delete mode 100644 test/fail/ok/M0200.tc.ret.ok

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 3eb1d64df7e..42a3b4b8561 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11256,7 +11256,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
     if not !Flags.import_component then (
       Printf.printf "%s" (Diag.string_of_message (
         Diag.error_message at "M0200" "import" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
-      exit 1);
+        exit 1);
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
     E.call_import env "component" "call"
diff --git a/test/fail/ok/M0200.tc.ok b/test/fail/ok/M0200.tc.ok
deleted file mode 100644
index 9d19d7d4ba0..00000000000
--- a/test/fail/ok/M0200.tc.ok
+++ /dev/null
@@ -1 +0,0 @@
-M0200.mo:3.8-3.28: import error [M0200], component import is unavailable (pass `-import-component` flag)
diff --git a/test/fail/ok/M0200.tc.ret.ok b/test/fail/ok/M0200.tc.ret.ok
deleted file mode 100644
index 69becfa16f9..00000000000
--- a/test/fail/ok/M0200.tc.ret.ok
+++ /dev/null
@@ -1 +0,0 @@
-Return code 1
diff --git a/test/fail/ok/no-timer-canc.tc.ok b/test/fail/ok/no-timer-canc.tc.ok
index 92026795a3e..186fc2c9afa 100644
--- a/test/fail/ok/no-timer-canc.tc.ok
+++ b/test/fail/ok/no-timer-canc.tc.ok
@@ -73,6 +73,7 @@ no-timer-canc.mo:3.10-3.21: type error [M0119], object field cancelTimer is not
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
+    componentCall : Nat32 -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;
diff --git a/test/fail/ok/no-timer-set.tc.ok b/test/fail/ok/no-timer-set.tc.ok
index 42632af93d9..784bc492652 100644
--- a/test/fail/ok/no-timer-set.tc.ok
+++ b/test/fail/ok/no-timer-set.tc.ok
@@ -73,6 +73,7 @@ no-timer-set.mo:3.10-3.18: type error [M0119], object field setTimer is not cont
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
+    componentCall : Nat32 -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;

From d18df6d5ba71da0c9dde097e8c8950c93005f9de Mon Sep 17 00:00:00 2001
From: Claudio Russo <claudio@dfinity.org>
Date: Fri, 28 Jun 2024 18:18:14 +0100
Subject: [PATCH 12/30] move M0200 error detection from compile.ml to
 typing.ml, using special @deprecation M0200 (#4584)

---
 src/codegen/compile.ml           | 5 +----
 src/mo_frontend/typing.ml        | 5 ++++-
 src/prelude/prim.mo              | 1 +
 test/fail/ok/M0200.tc.ok         | 2 +-
 test/fail/ok/no-timer-canc.tc.ok | 1 +
 test/fail/ok/no-timer-set.tc.ok  | 1 +
 6 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 3eb1d64df7e..f1fb8e5fb83 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11253,10 +11253,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
     E.call_import env "rts" "log" (* musl *)
 
   | OtherPrim "componentCall", [e] ->
-    if not !Flags.import_component then (
-      Printf.printf "%s" (Diag.string_of_message (
-        Diag.error_message at "M0200" "import" (Printf.sprintf "component import is unavailable (pass `-import-component` flag)")));
-      exit 1);
+    assert !Flags.import_component;
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
     E.call_import env "component" "call"
diff --git a/src/mo_frontend/typing.ml b/src/mo_frontend/typing.ml
index 136bdf4c708..0e8071a58a2 100644
--- a/src/mo_frontend/typing.ml
+++ b/src/mo_frontend/typing.ml
@@ -160,7 +160,10 @@ let check_deprecation env at desc id depr =
        | _ -> fun _ _ _ _ -> ())
        env at code
        "this code is (or uses) the deprecated library `ExperimentalStableMemory`.\nPlease use the `Region` library instead: https://internetcomputer.org/docs/current/motoko/main/stable-memory/stable-regions/#the-region-library or compile with flag `--experimental-stable-memory 1` to suppress this message."
-    end
+      end
+  | Some ("M0200" as code) ->
+    if not !Flags.import_component then
+      error env at code "component import is unavailable (pass `-import-component` flag)"
   | Some msg ->
     warn env at "M0154" "%s %s is deprecated:\n%s" desc id msg
   | None -> ()
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index cd9e11e853b..2ac9f98f4a9 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -269,6 +269,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 
 // Wasm component model functions
 
+/// @deprecated M0200
 func componentCall(n : Nat32) : Nat32 = (prim "componentCall" : Nat32 -> Nat32) n;
 
 // Array utilities
diff --git a/test/fail/ok/M0200.tc.ok b/test/fail/ok/M0200.tc.ok
index 9d19d7d4ba0..866b5baf5ad 100644
--- a/test/fail/ok/M0200.tc.ok
+++ b/test/fail/ok/M0200.tc.ok
@@ -1 +1 @@
-M0200.mo:3.8-3.28: import error [M0200], component import is unavailable (pass `-import-component` flag)
+M0200.mo:3.8-3.23: type error [M0200], component import is unavailable (pass `-import-component` flag)
diff --git a/test/fail/ok/no-timer-canc.tc.ok b/test/fail/ok/no-timer-canc.tc.ok
index 92026795a3e..186fc2c9afa 100644
--- a/test/fail/ok/no-timer-canc.tc.ok
+++ b/test/fail/ok/no-timer-canc.tc.ok
@@ -73,6 +73,7 @@ no-timer-canc.mo:3.10-3.21: type error [M0119], object field cancelTimer is not
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
+    componentCall : Nat32 -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;
diff --git a/test/fail/ok/no-timer-set.tc.ok b/test/fail/ok/no-timer-set.tc.ok
index 42632af93d9..784bc492652 100644
--- a/test/fail/ok/no-timer-set.tc.ok
+++ b/test/fail/ok/no-timer-set.tc.ok
@@ -73,6 +73,7 @@ no-timer-set.mo:3.10-3.18: type error [M0119], object field setTimer is not cont
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
+    componentCall : Nat32 -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;

From 3be8fd9013c32c608e44284c3aaedf07099c23f0 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 28 Jun 2024 11:23:51 -0600
Subject: [PATCH 13/30] Rename 'componentCall' prim to 'wit:component:call'

---
 src/codegen/compile.ml | 2 +-
 src/prelude/prim.mo    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index f1fb8e5fb83..c719a534cd6 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11252,7 +11252,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
     compile_exp_as env ae SR.UnboxedFloat64 e ^^
     E.call_import env "rts" "log" (* musl *)
 
-  | OtherPrim "componentCall", [e] ->
+  | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
     SR.UnboxedWord32 Type.Nat32,
     compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 2ac9f98f4a9..2cc763b01d0 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -270,7 +270,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 // Wasm component model functions
 
 /// @deprecated M0200
-func componentCall(n : Nat32) : Nat32 = (prim "componentCall" : Nat32 -> Nat32) n;
+func componentCall(n : Nat32) : Nat32 = (prim "wit:component:call" : Nat32 -> Nat32) n;
 
 // Array utilities
 

From 36bf9ad033f8917072f9321b1d25050da0b8be71 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 28 Jun 2024 12:01:01 -0600
Subject: [PATCH 14/30] Accept new test output

---
 test/fail/ok/M0200.tc.ok     | 2 +-
 test/fail/ok/M0200.tc.ret.ok | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 test/fail/ok/M0200.tc.ret.ok

diff --git a/test/fail/ok/M0200.tc.ok b/test/fail/ok/M0200.tc.ok
index 866b5baf5ad..7f473a1d286 100644
--- a/test/fail/ok/M0200.tc.ok
+++ b/test/fail/ok/M0200.tc.ok
@@ -1 +1 @@
-M0200.mo:3.8-3.23: type error [M0200], component import is unavailable (pass `-import-component` flag)
+M0200.mo:3.8-3.26: type error [M0200], component import is unavailable (pass `-import-component` flag)
diff --git a/test/fail/ok/M0200.tc.ret.ok b/test/fail/ok/M0200.tc.ret.ok
new file mode 100644
index 00000000000..69becfa16f9
--- /dev/null
+++ b/test/fail/ok/M0200.tc.ret.ok
@@ -0,0 +1 @@
+Return code 1

From 68bca73d4acd7eb5629d58ba5fa0d4d63e4cde01 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 28 Jun 2024 11:36:06 -0600
Subject: [PATCH 15/30] Set up `Blob -> Blob` function type

---
 src/codegen/compile.ml | 6 +++---
 src/prelude/prim.mo    | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index c719a534cd6..335e1178509 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11254,8 +11254,8 @@ and compile_prim_invocation (env : E.t) ae p es at =
 
   | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
-    SR.UnboxedWord32 Type.Nat32,
-    compile_exp_as env ae (SR.UnboxedWord32 Type.Nat32) e ^^
+    SR.Vanilla,
+    compile_exp_as env ae Sr.Vanilla e ^^
     E.call_import env "component" "call"
 
   (* Other prims, nullary *)
@@ -12826,7 +12826,7 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
 
   (* Wasm component model *)
   if !Flags.import_component then
-    E.add_func_import env "component" "call" [I32Type] [I32Type];
+    E.add_func_import env "component" "call" [I32Type; I32Type] [I32Type];
 
   compile_init_func env prog;
   let start_fi_o = match E.mode env with
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 2cc763b01d0..5a2a41a5148 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -270,7 +270,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 // Wasm component model functions
 
 /// @deprecated M0200
-func componentCall(n : Nat32) : Nat32 = (prim "wit:component:call" : Nat32 -> Nat32) n;
+func componentCall(b : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) b;
 
 // Array utilities
 

From 866e7786ad3d64bcb4ecf759b43e942739c0e820 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Mon, 1 Jul 2024 16:05:34 -0600
Subject: [PATCH 16/30] Temporarily use unboxed constant expressions

---
 src/codegen/compile.ml | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 335e1178509..762e034ae73 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11254,8 +11254,10 @@ and compile_prim_invocation (env : E.t) ae p es at =
 
   | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
-    SR.Vanilla,
-    compile_exp_as env ae Sr.Vanilla e ^^
+    SR.UnboxedWord32 Type.Nat32,
+    (* compile_exp_as env ae SR.Vanilla e ^^ *)
+    compile_unboxed_const 0l ^^
+    compile_unboxed_const 0l ^^
     E.call_import env "component" "call"
 
   (* Other prims, nullary *)

From 9100f65326184091216879f1b55759274c853e41 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 11:06:49 -0600
Subject: [PATCH 17/30] Use Blob arg in place of Nat32

---
 src/codegen/compile.ml | 8 +++++---
 src/prelude/prim.mo    | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 762e034ae73..a7e162d1ac3 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11255,9 +11255,11 @@ and compile_prim_invocation (env : E.t) ae p es at =
   | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
     SR.UnboxedWord32 Type.Nat32,
-    (* compile_exp_as env ae SR.Vanilla e ^^ *)
-    compile_unboxed_const 0l ^^
-    compile_unboxed_const 0l ^^
+    compile_exp_as env ae SR.Vanilla e ^^
+    let set_blob, get_blob = new_local env "blob" in
+    set_blob ^^
+    get_blob ^^ Blob.payload_ptr_unskewed env ^^
+    get_blob ^^ Blob.len env ^^
     E.call_import env "component" "call"
 
   (* Other prims, nullary *)
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 5a2a41a5148..69a740eebe8 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -270,7 +270,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 // Wasm component model functions
 
 /// @deprecated M0200
-func componentCall(b : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) b;
+func componentCall(b : Blob) : Nat32 = (prim "wit:component:call" : Blob -> Nat32) b;
 
 // Array utilities
 

From fabbb7ce4f337b2e1ee3e8471cf0a2e5a7ec286c Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 13:25:25 -0600
Subject: [PATCH 18/30] Progress

---
 rts/motoko-rts/src/component.rs | 23 +++++++++++++++++++++++
 rts/motoko-rts/src/lib.rs       |  1 +
 src/codegen/compile.ml          |  5 +++--
 3 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 rts/motoko-rts/src/component.rs

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
new file mode 100644
index 00000000000..51a48fa4a0d
--- /dev/null
+++ b/rts/motoko-rts/src/component.rs
@@ -0,0 +1,23 @@
+// Wasm Component Model utilities
+
+use crate::{
+    barriers::allocation_barrier,
+    memory::{alloc_blob, Memory},
+    types::Value,
+    Bytes,
+};
+use alloc::vec::Vec;
+use motoko_rts_macros::ic_mem_fn;
+
+/// Convert a Canonical ABI `list<u8>` to a Motoko `Blob`.
+#[ic_mem_fn]
+unsafe fn blob_of_cabi_list_u8<M: Memory>(mem: &mut M, vec: Vec<u8>) -> Value {
+    let value = alloc_blob(mem, Bytes(vec.len() as u32));
+    let blob = value.as_blob_mut();
+    let mut dest = blob.payload_addr();
+    for item in vec.into_iter() {
+        *dest = item;
+        dest = dest.add(1);
+    }
+    allocation_barrier(value)
+}
diff --git a/rts/motoko-rts/src/lib.rs b/rts/motoko-rts/src/lib.rs
index fd2f6f169e0..94f303cf6ae 100644
--- a/rts/motoko-rts/src/lib.rs
+++ b/rts/motoko-rts/src/lib.rs
@@ -26,6 +26,7 @@ pub mod bitrel;
 mod blob_iter;
 pub mod buf;
 mod char;
+mod component;
 pub mod constants;
 pub mod continuation_table;
 #[cfg(feature = "ic")]
diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index a7e162d1ac3..8c190d7f61d 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -1258,7 +1258,7 @@ module RTS = struct
     E.add_func_import env "rts" "stream_split" [I32Type] [I32Type];
     E.add_func_import env "rts" "stream_shutdown" [I32Type] [];
     E.add_func_import env "rts" "stream_reserve" [I32Type; I32Type] [I32Type];
-    E.add_func_import env "rts" "stream_stable_dest" [I32Type; I64Type; I64Type] [];
+    E.add_func_import env "rts" "blob_of_cabi_list_u8" [I32Type; I32Type] [I32Type];
     if !Flags.gc_strategy = Flags.Incremental then
       incremental_gc_imports env
     else
@@ -11260,7 +11260,8 @@ and compile_prim_invocation (env : E.t) ae p es at =
     set_blob ^^
     get_blob ^^ Blob.payload_ptr_unskewed env ^^
     get_blob ^^ Blob.len env ^^
-    E.call_import env "component" "call"
+    E.call_import env "component" "call" ^^
+    E.call_import env "rts" "blob_of_cabi_list_u8"
 
   (* Other prims, nullary *)
 

From 64d0091221ed652abaf10a100d79950cb121f43d Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 13:54:31 -0600
Subject: [PATCH 19/30] Accept new test output

---
 test/fail/ok/no-timer-canc.tc.ok | 2 +-
 test/fail/ok/no-timer-set.tc.ok  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/fail/ok/no-timer-canc.tc.ok b/test/fail/ok/no-timer-canc.tc.ok
index 186fc2c9afa..155084b6da8 100644
--- a/test/fail/ok/no-timer-canc.tc.ok
+++ b/test/fail/ok/no-timer-canc.tc.ok
@@ -73,7 +73,7 @@ no-timer-canc.mo:3.10-3.21: type error [M0119], object field cancelTimer is not
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
-    componentCall : Nat32 -> Nat32;
+    componentCall : Blob -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;
diff --git a/test/fail/ok/no-timer-set.tc.ok b/test/fail/ok/no-timer-set.tc.ok
index 784bc492652..96201e3c855 100644
--- a/test/fail/ok/no-timer-set.tc.ok
+++ b/test/fail/ok/no-timer-set.tc.ok
@@ -73,7 +73,7 @@ no-timer-set.mo:3.10-3.18: type error [M0119], object field setTimer is not cont
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
-    componentCall : Nat32 -> Nat32;
+    componentCall : Blob -> Nat32;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;

From 5d9d4965857da9d9d91ef00213cfbc2f7867118c Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 17:40:27 -0600
Subject: [PATCH 20/30] Implement Blob return value

---
 rts/motoko-rts/src/component.rs | 18 ++++++++++--------
 src/codegen/compile.ml          | 17 ++++++++++++-----
 src/prelude/prim.mo             |  2 +-
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
index 51a48fa4a0d..b8475cf5e93 100644
--- a/rts/motoko-rts/src/component.rs
+++ b/rts/motoko-rts/src/component.rs
@@ -6,18 +6,20 @@ use crate::{
     types::Value,
     Bytes,
 };
-use alloc::vec::Vec;
 use motoko_rts_macros::ic_mem_fn;
 
-/// Convert a Canonical ABI `list<u8>` to a Motoko `Blob`.
+/// Convert a Canonical ABI `list<u8>` pointer to a Motoko `Blob`.
 #[ic_mem_fn]
-unsafe fn blob_of_cabi_list_u8<M: Memory>(mem: &mut M, vec: Vec<u8>) -> Value {
-    let value = alloc_blob(mem, Bytes(vec.len() as u32));
+unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const u32) -> Value {
+    let items = *ret as *const u8; // Note: 32-bit address
+    let len = *ret.add(1);
+
+    // TODO: use existing Blob from `cabi_realloc`?
+    let value = alloc_blob(mem, Bytes(len));
     let blob = value.as_blob_mut();
-    let mut dest = blob.payload_addr();
-    for item in vec.into_iter() {
-        *dest = item;
-        dest = dest.add(1);
+    let dest = blob.payload_addr();
+    for i in 0..len as usize {
+        *dest.add(i) = *items.add(i);
     }
     allocation_barrier(value)
 }
diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 8c190d7f61d..1da721c8058 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -1258,7 +1258,7 @@ module RTS = struct
     E.add_func_import env "rts" "stream_split" [I32Type] [I32Type];
     E.add_func_import env "rts" "stream_shutdown" [I32Type] [];
     E.add_func_import env "rts" "stream_reserve" [I32Type; I32Type] [I32Type];
-    E.add_func_import env "rts" "blob_of_cabi_list_u8" [I32Type; I32Type] [I32Type];
+    E.add_func_import env "rts" "blob_of_cabi" [I32Type] [I32Type];
     if !Flags.gc_strategy = Flags.Incremental then
       incremental_gc_imports env
     else
@@ -11255,13 +11255,20 @@ and compile_prim_invocation (env : E.t) ae p es at =
   | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
     SR.UnboxedWord32 Type.Nat32,
-    compile_exp_as env ae SR.Vanilla e ^^
+    (* Read blob pointer and length *)
     let set_blob, get_blob = new_local env "blob" in
-    set_blob ^^
+    compile_exp_as env ae SR.Vanilla e ^^ set_blob ^^
+    (* Allocate return value *)
+    let set_ret, get_ret = new_local env "ret" in
+    (* TODO: optimize *)
+    Blob.lit env "\x00\x00" ^^ set_ret ^^
+    (* Call component export *)
     get_blob ^^ Blob.payload_ptr_unskewed env ^^
     get_blob ^^ Blob.len env ^^
+    get_ret ^^ Blob.payload_ptr_unskewed env ^^
     E.call_import env "component" "call" ^^
-    E.call_import env "rts" "blob_of_cabi_list_u8"
+    get_ret ^^
+    E.call_import env "rts" "blob_of_cabi"
 
   (* Other prims, nullary *)
 
@@ -12831,7 +12838,7 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
 
   (* Wasm component model *)
   if !Flags.import_component then
-    E.add_func_import env "component" "call" [I32Type; I32Type] [I32Type];
+    E.add_func_import env "component" "call" [I32Type; I32Type; I32Type] [];
 
   compile_init_func env prog;
   let start_fi_o = match E.mode env with
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 69a740eebe8..5a2a41a5148 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -270,7 +270,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 // Wasm component model functions
 
 /// @deprecated M0200
-func componentCall(b : Blob) : Nat32 = (prim "wit:component:call" : Blob -> Nat32) b;
+func componentCall(b : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) b;
 
 // Array utilities
 

From 1397ed853dc737789cd5beb5253888cad93caa3f Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 17:41:08 -0600
Subject: [PATCH 21/30] Rename local variable

---
 src/prelude/prim.mo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 5a2a41a5148..90b6983fc5a 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -270,7 +270,7 @@ func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 // Wasm component model functions
 
 /// @deprecated M0200
-func componentCall(b : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) b;
+func componentCall(value : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) value;
 
 // Array utilities
 

From 1a6b821c033860bec305ebe45d8708a609b192ca Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Wed, 10 Jul 2024 18:18:11 -0600
Subject: [PATCH 22/30] Set up 'cabi_realloc'

---
 rts/motoko-rts/src/component.rs | 30 ++++++++++++++++++++++++++++++
 src/codegen/compile.ml          | 14 ++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
index b8475cf5e93..6a3a00d04b4 100644
--- a/rts/motoko-rts/src/component.rs
+++ b/rts/motoko-rts/src/component.rs
@@ -23,3 +23,33 @@ unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const u32) -> Value {
     }
     allocation_barrier(value)
 }
+
+/// Canonical ABI allocation logic.
+/// Derived from: https://docs.rs/wit-bindgen-rt/0.27.0/src/wit_bindgen_rt/lib.rs.html#54-88
+#[ic_mem_fn]
+unsafe fn cabi_realloc<M: Memory>(
+    _mem: &mut M,
+    old_ptr: *mut u8,
+    old_len: usize,
+    align: usize,
+    new_len: usize,
+) -> *mut u8 {
+    use ::alloc::alloc::{self, Layout};
+
+    let layout;
+    let ptr = if old_len == 0 {
+        if new_len == 0 {
+            return align as *mut u8;
+        }
+        layout = Layout::from_size_align_unchecked(new_len, align);
+        alloc::alloc(layout)
+    } else {
+        debug_assert_ne!(new_len, 0, "non-zero old_len requires non-zero new_len!");
+        layout = Layout::from_size_align_unchecked(old_len, align);
+        alloc::realloc(old_ptr, layout, new_len)
+    };
+    if ptr.is_null() {
+        unreachable!();
+    }
+    return ptr;
+}
diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 1da721c8058..3ef5982dd17 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -1259,6 +1259,7 @@ module RTS = struct
     E.add_func_import env "rts" "stream_shutdown" [I32Type] [];
     E.add_func_import env "rts" "stream_reserve" [I32Type; I32Type] [I32Type];
     E.add_func_import env "rts" "blob_of_cabi" [I32Type] [I32Type];
+    E.add_func_import env "rts" "cabi_realloc" [I32Type; I32Type; I32Type; I32Type] [I32Type];
     if !Flags.gc_strategy = Flags.Incremental then
       incremental_gc_imports env
     else
@@ -6337,6 +6338,19 @@ module RTS_Exports = struct
     E.add_export env (nr {
       name = Lib.Utf8.decode "moc_stable_mem_set_version";
       edesc = nr (FuncExport (nr moc_stable_mem_set_version_fi))
+    });
+
+    let cabi_realloc =
+      E.add_fun env "cabi_realloc" (
+        Func.of_body env ["ptr", I32Type; "len", I32Type; "align", I32Type; "new_len", I32Type] [I32Type]
+          (fun env ->
+            E.call_import env "rts" "cabi_realloc"
+          )
+        )
+    in
+    E.add_export env (nr {
+      name = Lib.Utf8.decode "cabi_realloc";
+      edesc = nr (FuncExport (nr cabi_realloc))
     })
 
 end (* RTS_Exports *)

From c75164056a055865434d894f6a942c290634e84e Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 11 Jul 2024 11:10:25 -0600
Subject: [PATCH 23/30] Export 'cabi_realloc'

---
 src/codegen/compile.ml              | 21 ++++-----------------
 src/lang_utils/error_codes/M0200.md |  2 +-
 src/linking/linkModule.ml           |  1 +
 src/prelude/prim.mo                 |  2 +-
 4 files changed, 7 insertions(+), 19 deletions(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 3ef5982dd17..dc7034eab32 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -1258,8 +1258,9 @@ module RTS = struct
     E.add_func_import env "rts" "stream_split" [I32Type] [I32Type];
     E.add_func_import env "rts" "stream_shutdown" [I32Type] [];
     E.add_func_import env "rts" "stream_reserve" [I32Type; I32Type] [I32Type];
-    E.add_func_import env "rts" "blob_of_cabi" [I32Type] [I32Type];
-    E.add_func_import env "rts" "cabi_realloc" [I32Type; I32Type; I32Type; I32Type] [I32Type];
+    if !Flags.import_component then (
+      E.add_func_import env "rts" "blob_of_cabi" [I32Type] [I32Type];
+      E.add_func_import env "rts" "cabi_realloc" [I32Type; I32Type; I32Type; I32Type] [I32Type]);
     if !Flags.gc_strategy = Flags.Incremental then
       incremental_gc_imports env
     else
@@ -5260,7 +5261,6 @@ module IC = struct
       edesc = nr (FuncExport (nr post_upgrade_fi))
     })
 
-
   let get_self_reference env =
     match E.mode env with
     | Flags.ICMode | Flags.RefMode ->
@@ -6340,19 +6340,6 @@ module RTS_Exports = struct
       edesc = nr (FuncExport (nr moc_stable_mem_set_version_fi))
     });
 
-    let cabi_realloc =
-      E.add_fun env "cabi_realloc" (
-        Func.of_body env ["ptr", I32Type; "len", I32Type; "align", I32Type; "new_len", I32Type] [I32Type]
-          (fun env ->
-            E.call_import env "rts" "cabi_realloc"
-          )
-        )
-    in
-    E.add_export env (nr {
-      name = Lib.Utf8.decode "cabi_realloc";
-      edesc = nr (FuncExport (nr cabi_realloc))
-    })
-
 end (* RTS_Exports *)
 
 
@@ -12850,7 +12837,7 @@ let compile mode rts (prog : Ir.prog) : Wasm_exts.CustomModule.extended_module =
   IC.system_imports env;
   RTS.system_imports env;
 
-  (* Wasm component model *)
+  (* Wasm Component Model *)
   if !Flags.import_component then
     E.add_func_import env "component" "call" [I32Type; I32Type; I32Type] [];
 
diff --git a/src/lang_utils/error_codes/M0200.md b/src/lang_utils/error_codes/M0200.md
index 09e040ac8f3..5f200ab4425 100644
--- a/src/lang_utils/error_codes/M0200.md
+++ b/src/lang_utils/error_codes/M0200.md
@@ -1,5 +1,5 @@
 # M0200
 
-This error indicates that the Wasm component model (cross-language) functionality is not enabled. 
+This error indicates that the Wasm Component Model (cross-language) functionality is not enabled. 
 
 You can fix this by passing the `-import-component` compiler flag, e.g. `moc -wasi-system-api -import-component ...`.
diff --git a/src/linking/linkModule.ml b/src/linking/linkModule.ml
index f48f9e67eca..c24e52c02d1 100644
--- a/src/linking/linkModule.ml
+++ b/src/linking/linkModule.ml
@@ -258,6 +258,7 @@ let remove_non_ic_exports (em : extended_module) : extended_module =
    exported in the final module *)
   let is_ic_export (exp : export) =
     Lib.String.chop_prefix "canister_" (Lib.Utf8.encode exp.it.name) <> None ||
+    (!Mo_config.Flags.import_component && Lib.String.chop_prefix "cabi_" (Lib.Utf8.encode exp.it.name) <> None) || (* Wasm Component Model *)
     "_start" = Lib.Utf8.encode exp.it.name
   in
 
diff --git a/src/prelude/prim.mo b/src/prelude/prim.mo
index 90b6983fc5a..93376bdcc7c 100644
--- a/src/prelude/prim.mo
+++ b/src/prelude/prim.mo
@@ -267,7 +267,7 @@ func arctan2(y : Float, x : Float) : Float = (prim "fatan2" : (Float, Float) ->
 func exp(f : Float) : Float = (prim "fexp" : Float -> Float) f;
 func log(f : Float) : Float = (prim "flog" : Float -> Float) f;
 
-// Wasm component model functions
+// Wasm Component Model functions
 
 /// @deprecated M0200
 func componentCall(value : Blob) : Blob = (prim "wit:component:call" : Blob -> Blob) value;

From 97a5ebb3dc415a9395d174c50dc3c7b0eff53777 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 11 Jul 2024 11:29:36 -0600
Subject: [PATCH 24/30] Simplify

---
 rts/motoko-rts/src/component.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
index 6a3a00d04b4..3892330ea3a 100644
--- a/rts/motoko-rts/src/component.rs
+++ b/rts/motoko-rts/src/component.rs
@@ -14,7 +14,7 @@ unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const u32) -> Value {
     let items = *ret as *const u8; // Note: 32-bit address
     let len = *ret.add(1);
 
-    // TODO: use existing Blob from `cabi_realloc`?
+    // TODO: reuse memory space from `cabi_realloc`?
     let value = alloc_blob(mem, Bytes(len));
     let blob = value.as_blob_mut();
     let dest = blob.payload_addr();
@@ -51,5 +51,5 @@ unsafe fn cabi_realloc<M: Memory>(
     if ptr.is_null() {
         unreachable!();
     }
-    return ptr;
+    ptr
 }

From 93f50893675d0000f3d6a50bb8dacd98263b7d28 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Thu, 11 Jul 2024 12:47:07 -0600
Subject: [PATCH 25/30] Working 'Blob -> Blob' component call logic

---
 rts/motoko-rts/src/component.rs | 12 +++++++-----
 src/codegen/compile.ml          |  6 +++---
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
index 3892330ea3a..5553ac0c5a4 100644
--- a/rts/motoko-rts/src/component.rs
+++ b/rts/motoko-rts/src/component.rs
@@ -6,16 +6,18 @@ use crate::{
     types::Value,
     Bytes,
 };
+use alloc as alloc_crate;
+use core::convert::TryInto;
 use motoko_rts_macros::ic_mem_fn;
 
 /// Convert a Canonical ABI `list<u8>` pointer to a Motoko `Blob`.
 #[ic_mem_fn]
-unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const u32) -> Value {
-    let items = *ret as *const u8; // Note: 32-bit address
+unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const usize) -> Value {
+    let items = *ret as *const u8;
     let len = *ret.add(1);
 
-    // TODO: reuse memory space from `cabi_realloc`?
-    let value = alloc_blob(mem, Bytes(len));
+    // TODO: reuse Blob from `cabi_realloc`?
+    let value = alloc_blob(mem, Bytes(len.try_into().unwrap())); // Checked conversion from `usize` to `u32`
     let blob = value.as_blob_mut();
     let dest = blob.payload_addr();
     for i in 0..len as usize {
@@ -34,7 +36,7 @@ unsafe fn cabi_realloc<M: Memory>(
     align: usize,
     new_len: usize,
 ) -> *mut u8 {
-    use ::alloc::alloc::{self, Layout};
+    use alloc_crate::alloc::{self, Layout};
 
     let layout;
     let ptr = if old_len == 0 {
diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index dc7034eab32..3747a13735e 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11255,20 +11255,20 @@ and compile_prim_invocation (env : E.t) ae p es at =
 
   | OtherPrim "wit:component:call", [e] ->
     assert !Flags.import_component;
-    SR.UnboxedWord32 Type.Nat32,
+    SR.Vanilla,
     (* Read blob pointer and length *)
     let set_blob, get_blob = new_local env "blob" in
     compile_exp_as env ae SR.Vanilla e ^^ set_blob ^^
     (* Allocate return value *)
     let set_ret, get_ret = new_local env "ret" in
-    (* TODO: optimize *)
+    (* TODO: optimize? *)
     Blob.lit env "\x00\x00" ^^ set_ret ^^
     (* Call component export *)
     get_blob ^^ Blob.payload_ptr_unskewed env ^^
     get_blob ^^ Blob.len env ^^
     get_ret ^^ Blob.payload_ptr_unskewed env ^^
     E.call_import env "component" "call" ^^
-    get_ret ^^
+    get_ret ^^ Blob.payload_ptr_unskewed env ^^
     E.call_import env "rts" "blob_of_cabi"
 
   (* Other prims, nullary *)

From b6df7a1e600ec3ac26760f1e391c15cacf39668b Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 12 Jul 2024 09:22:51 -0600
Subject: [PATCH 26/30] Misc

---
 rts/motoko-rts/src/component.rs | 4 ++--
 src/codegen/compile.ml          | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/rts/motoko-rts/src/component.rs b/rts/motoko-rts/src/component.rs
index 5553ac0c5a4..f74805d5a2c 100644
--- a/rts/motoko-rts/src/component.rs
+++ b/rts/motoko-rts/src/component.rs
@@ -13,7 +13,7 @@ use motoko_rts_macros::ic_mem_fn;
 /// Convert a Canonical ABI `list<u8>` pointer to a Motoko `Blob`.
 #[ic_mem_fn]
 unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const usize) -> Value {
-    let items = *ret as *const u8;
+    let content = *ret as *const u8;
     let len = *ret.add(1);
 
     // TODO: reuse Blob from `cabi_realloc`?
@@ -21,7 +21,7 @@ unsafe fn blob_of_cabi<M: Memory>(mem: &mut M, ret: *const usize) -> Value {
     let blob = value.as_blob_mut();
     let dest = blob.payload_addr();
     for i in 0..len as usize {
-        *dest.add(i) = *items.add(i);
+        *dest.add(i) = *content.add(i);
     }
     allocation_barrier(value)
 }
diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 3747a13735e..d2c4b1e4aba 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -11262,7 +11262,7 @@ and compile_prim_invocation (env : E.t) ae p es at =
     (* Allocate return value *)
     let set_ret, get_ret = new_local env "ret" in
     (* TODO: optimize? *)
-    Blob.lit env "\x00\x00" ^^ set_ret ^^
+    Blob.lit env "\x00\x00\x00\x00\x00\x00\x00\x00" ^^ set_ret ^^ (* pointer, length *)
     (* Call component export *)
     get_blob ^^ Blob.payload_ptr_unskewed env ^^
     get_blob ^^ Blob.len env ^^

From cd5fa0204c472f65d0c3fda59d6637de301d94bd Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 19 Jul 2024 16:03:25 -0600
Subject: [PATCH 27/30] Fix missing RTS import

---
 src/codegen/compile.ml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index d2c4b1e4aba..e72553316a5 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -1258,6 +1258,7 @@ module RTS = struct
     E.add_func_import env "rts" "stream_split" [I32Type] [I32Type];
     E.add_func_import env "rts" "stream_shutdown" [I32Type] [];
     E.add_func_import env "rts" "stream_reserve" [I32Type; I32Type] [I32Type];
+    E.add_func_import env "rts" "stream_stable_dest" [I32Type; I64Type; I64Type] [];
     if !Flags.import_component then (
       E.add_func_import env "rts" "blob_of_cabi" [I32Type] [I32Type];
       E.add_func_import env "rts" "cabi_realloc" [I32Type; I32Type; I32Type; I32Type] [I32Type]);

From 4b95c4f31faf757c7786aba23c479caae2112352 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 19 Jul 2024 16:05:28 -0600
Subject: [PATCH 28/30] Reduce diff

---
 src/codegen/compile.ml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/codegen/compile.ml b/src/codegen/compile.ml
index 1458b70cadd..82b52c64607 100644
--- a/src/codegen/compile.ml
+++ b/src/codegen/compile.ml
@@ -5266,6 +5266,7 @@ module IC = struct
       edesc = nr (FuncExport (nr post_upgrade_fi))
     })
 
+
   let get_self_reference env =
     match E.mode env with
     | Flags.ICMode | Flags.RefMode ->
@@ -6343,7 +6344,7 @@ module RTS_Exports = struct
     E.add_export env (nr {
       name = Lib.Utf8.decode "moc_stable_mem_set_version";
       edesc = nr (FuncExport (nr moc_stable_mem_set_version_fi))
-    });
+    })
 
 end (* RTS_Exports *)
 

From bf1fe7d9a6614578daac1e9cea3fd9a63c5f590d Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 19 Jul 2024 16:59:22 -0600
Subject: [PATCH 29/30] Update heap-32 test

---
 test/bench/ok/heap-32.drun-run-opt.ok | 2 +-
 test/bench/ok/heap-32.drun-run.ok     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/bench/ok/heap-32.drun-run-opt.ok b/test/bench/ok/heap-32.drun-run-opt.ok
index faf3bfb29da..f5ae73261f4 100644
--- a/test/bench/ok/heap-32.drun-run-opt.ok
+++ b/test/bench/ok/heap-32.drun-run-opt.ok
@@ -1,5 +1,5 @@
 ingress Completed: Reply: 0x4449444c016c01b3c4b1f204680100010a00000000000000000101
 ingress Completed: Reply: 0x4449444c0000
 debug.print: (50_227, +29_863_068, 708_174_952)
-debug.print: (50_070, +32_992_212, 766_613_680)
+debug.print: (50_070, +32_992_212, 766_613_760)
 ingress Completed: Reply: 0x4449444c0000
diff --git a/test/bench/ok/heap-32.drun-run.ok b/test/bench/ok/heap-32.drun-run.ok
index f51bd0ff0c3..b67b6f2e41b 100644
--- a/test/bench/ok/heap-32.drun-run.ok
+++ b/test/bench/ok/heap-32.drun-run.ok
@@ -1,5 +1,5 @@
 ingress Completed: Reply: 0x4449444c016c01b3c4b1f204680100010a00000000000000000101
 ingress Completed: Reply: 0x4449444c0000
 debug.print: (50_227, +29_863_068, 769_000_085)
-debug.print: (50_070, +32_992_212, 830_427_376)
+debug.print: (50_070, +32_992_212, 830_427_500)
 ingress Completed: Reply: 0x4449444c0000

From 39125814f236f462c950594670a7e01a3f15dc35 Mon Sep 17 00:00:00 2001
From: rvanasa <ryan.vandersmith@dfinity.org>
Date: Fri, 19 Jul 2024 17:21:07 -0600
Subject: [PATCH 30/30] Adjust more tests

---
 test/fail/ok/no-timer-canc.tc.ok | 2 +-
 test/fail/ok/no-timer-set.tc.ok  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/fail/ok/no-timer-canc.tc.ok b/test/fail/ok/no-timer-canc.tc.ok
index d7ae69fa6f1..c404544e2c6 100644
--- a/test/fail/ok/no-timer-canc.tc.ok
+++ b/test/fail/ok/no-timer-canc.tc.ok
@@ -74,7 +74,7 @@ no-timer-canc.mo:3.10-3.21: type error [M0119], object field cancelTimer is not
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
-    componentCall : Blob -> Nat32;
+    componentCall : Blob -> Blob;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;
diff --git a/test/fail/ok/no-timer-set.tc.ok b/test/fail/ok/no-timer-set.tc.ok
index 41a1e2922ac..89c1a56824b 100644
--- a/test/fail/ok/no-timer-set.tc.ok
+++ b/test/fail/ok/no-timer-set.tc.ok
@@ -74,7 +74,7 @@ no-timer-set.mo:3.10-3.18: type error [M0119], object field setTimer is not cont
     clzNat32 : Nat32 -> Nat32;
     clzNat64 : Nat64 -> Nat64;
     clzNat8 : Nat8 -> Nat8;
-    componentCall : Blob -> Nat32;
+    componentCall : Blob -> Blob;
     cos : Float -> Float;
     createActor : (Blob, Blob) -> async Principal;
     ctzInt16 : Int16 -> Int16;