From 1a969aa9e418ddb3176c0fcc404754dbb49aeeb3 Mon Sep 17 00:00:00 2001
From: whitequark <whitequark@whitequark.org>
Date: Fri, 7 Aug 2015 07:54:35 +0300
Subject: [PATCH] compiler.transforms.inferencer: accept and ignore @kernel
 decorator.

---
 artiq/compiler/builtins.py              | 3 +++
 artiq/compiler/prelude.py               | 1 +
 artiq/compiler/transforms/inferencer.py | 7 +++++--
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/artiq/compiler/builtins.py b/artiq/compiler/builtins.py
index 903900540..6b9feb9e2 100644
--- a/artiq/compiler/builtins.py
+++ b/artiq/compiler/builtins.py
@@ -146,6 +146,9 @@ def fn_round():
 def fn_print():
     return types.TBuiltinFunction("print")
 
+def fn_kernel():
+    return types.TBuiltinFunction("kernel")
+
 def fn_syscall():
     return types.TBuiltinFunction("syscall")
 
diff --git a/artiq/compiler/prelude.py b/artiq/compiler/prelude.py
index 600b7a800..3c58674c6 100644
--- a/artiq/compiler/prelude.py
+++ b/artiq/compiler/prelude.py
@@ -19,5 +19,6 @@ def globals():
         "len":                  builtins.fn_len(),
         "round":                builtins.fn_round(),
         "print":                builtins.fn_print(),
+        "kernel":               builtins.fn_kernel(),
         "syscall":              builtins.fn_syscall(),
     }
diff --git a/artiq/compiler/transforms/inferencer.py b/artiq/compiler/transforms/inferencer.py
index 57aa9247d..e0338dcdc 100644
--- a/artiq/compiler/transforms/inferencer.py
+++ b/artiq/compiler/transforms/inferencer.py
@@ -887,10 +887,13 @@ class Inferencer(algorithm.Visitor):
                         arg.loc, default.loc)
 
     def visit_FunctionDefT(self, node):
-        if any(node.decorator_list):
+        for index, decorator in enumerate(node.decorator_list):
+            if types.is_builtin(decorator.type, "kernel"):
+                continue
+
             diag = diagnostic.Diagnostic("error",
                 "decorators are not supported", {},
-                node.at_locs[0], [node.decorator_list[0].loc])
+                node.at_locs[index], [decorator.loc])
             self.engine.process(diag)
             return