From a676b5acf6ee9c17926cf9786370d30a077d99c0 Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Sat, 15 Sep 2018 16:06:58 +1000
Subject: [PATCH] py/emitnative: Support arbitrary number of arguments to viper
 functions.

---
 py/emitnative.c                      |  7 -------
 tests/micropython/viper_args.py      | 10 +++++++++-
 tests/micropython/viper_args.py.exp  |  2 ++
 tests/micropython/viper_error.py     |  3 ---
 tests/micropython/viper_error.py.exp |  1 -
 5 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/py/emitnative.c b/py/emitnative.c
index b26beb4075..4188b4256f 100644
--- a/py/emitnative.c
+++ b/py/emitnative.c
@@ -295,13 +295,6 @@ STATIC void emit_native_start_pass(emit_t *emit, pass_kind_t pass, scope_t *scop
     // generate code for entry to function
 
     if (emit->do_viper_types) {
-
-        // right now we have a restriction of maximum of 4 arguments
-        if (scope->num_pos_args > REG_ARG_NUM) {
-            EMIT_NATIVE_VIPER_TYPE_ERROR(emit, "Viper functions don't currently support more than 4 arguments");
-            return;
-        }
-
         // Work out size of state (locals plus stack)
         // n_state counts all stack and locals, even those in registers
         emit->n_state = scope->num_locals + scope->stack_size;
diff --git a/tests/micropython/viper_args.py b/tests/micropython/viper_args.py
index 2aebe1b048..ee8e82321f 100644
--- a/tests/micropython/viper_args.py
+++ b/tests/micropython/viper_args.py
@@ -25,7 +25,15 @@ def f4(x1:int, x2:int, x3:int, x4:int):
     print(x1, x2, x3, x4)
 f4(1, 2, 3, 4)
 
-# only up to 4 arguments currently supported
+@micropython.viper
+def f5(x1:int, x2:int, x3:int, x4:int, x5:int):
+    print(x1, x2, x3, x4, x5)
+f5(1, 2, 3, 4, 5)
+
+@micropython.viper
+def f6(x1:int, x2:int, x3:int, x4:int, x5:int, x6:int):
+    print(x1, x2, x3, x4, x5, x6)
+f6(1, 2, 3, 4, 5, 6)
 
 # test compiling *x, **x, * args (currently unsupported at runtime)
 @micropython.viper
diff --git a/tests/micropython/viper_args.py.exp b/tests/micropython/viper_args.py.exp
index 0ca0f4e906..6d64c584a5 100644
--- a/tests/micropython/viper_args.py.exp
+++ b/tests/micropython/viper_args.py.exp
@@ -3,3 +3,5 @@
 1 2
 1 2 3
 1 2 3 4
+1 2 3 4 5
+1 2 3 4 5 6
diff --git a/tests/micropython/viper_error.py b/tests/micropython/viper_error.py
index 8472572854..ff32f54739 100644
--- a/tests/micropython/viper_error.py
+++ b/tests/micropython/viper_error.py
@@ -13,9 +13,6 @@ test("@micropython.viper\ndef f() -> 1: pass")
 # unknown type
 test("@micropython.viper\ndef f(x:unknown_type): pass")
 
-# too many arguments
-test("@micropython.viper\ndef f(a, b, c, d, e): pass")
-
 # local used before type known
 test("""
 @micropython.viper
diff --git a/tests/micropython/viper_error.py.exp b/tests/micropython/viper_error.py.exp
index 66bcad1f7d..da9a0ca93e 100644
--- a/tests/micropython/viper_error.py.exp
+++ b/tests/micropython/viper_error.py.exp
@@ -1,7 +1,6 @@
 SyntaxError('annotation must be an identifier',)
 SyntaxError('annotation must be an identifier',)
 ViperTypeError("unknown type 'unknown_type'",)
-ViperTypeError("Viper functions don't currently support more than 4 arguments",)
 ViperTypeError("local 'x' used before type known",)
 ViperTypeError("local 'x' has type 'int' but source is 'object'",)
 ViperTypeError("can't implicitly convert 'ptr' to 'bool'",)