Add exception constructor types.

artiq/py2llvm/builtins.py

@@ -37,6 +37,10 @@ class TRange(types.TMono):
             elt = types.TVar()
         super().__init__("range", {"elt": elt})
 
+class TException(types.TMono):
+    def __init__(self):
+        super().__init__("Exception")
+
 def fn_bool():
     return types.TConstructor("bool")
 
@@ -49,6 +53,9 @@ def fn_float():
 def fn_list():
     return types.TConstructor("list")
 
+def fn_Exception():
+    return types.TExceptionConstructor("Exception")
+
 def fn_range():
     return types.TBuiltinFunction("range")
 
@@ -70,7 +77,7 @@ def is_bool(typ):
     return types.is_mono(typ, "bool")
 
 def is_int(typ, width=None):
-    if width:
+    if width is not None:
         return types.is_mono(typ, "int", {"width": width})
     else:
         return types.is_mono(typ, "int")
@@ -88,13 +95,13 @@ def is_numeric(typ):
         typ.name in ('int', 'float')
 
 def is_list(typ, elt=None):
-    if elt:
+    if elt is not None:
         return types.is_mono(typ, "list", {"elt": elt})
     else:
         return types.is_mono(typ, "list")
 
 def is_range(typ, elt=None):
-    if elt:
+    if elt is not None:
         return types.is_mono(typ, "range", {"elt": elt})
     else:
         return types.is_mono(typ, "range")
@@ -117,3 +124,11 @@ def is_builtin(typ, name):
     typ = typ.find()
     return isinstance(typ, types.TBuiltin) and \
         typ.name == name
+
+def is_exception(typ, name=None):
+    typ = typ.find()
+    if name is not None:
+        return isinstance(typ, types.TExceptionConstructor) and \
+            typ.name == name
+    else:
+        return isinstance(typ, types.TExceptionConstructor)

artiq/py2llvm/prelude.py

@@ -7,12 +7,13 @@ from . import builtins
 
 def globals():
     return {
-        "bool":    builtins.fn_bool(),
-        "int":     builtins.fn_int(),
-        "float":   builtins.fn_float(),
-        "list":    builtins.fn_list(),
-        "range":   builtins.fn_range(),
-        "len":     builtins.fn_len(),
-        "round":   builtins.fn_round(),
-        "syscall": builtins.fn_syscall(),
+        "bool":         builtins.fn_bool(),
+        "int":          builtins.fn_int(),
+        "float":        builtins.fn_float(),
+        "list":         builtins.fn_list(),
+        "range":        builtins.fn_range(),
+        "Exception":    builtins.fn_Exception(),
+        "len":          builtins.fn_len(),
+        "round":        builtins.fn_round(),
+        "syscall":      builtins.fn_syscall(),
     }

lit-test/py2llvm/typing/exception.py

@@ -0,0 +1,5 @@
+# RUN: %python -m artiq.py2llvm.typing %s >%t
+# RUN: OutputCheck %s --file-to-check=%t
+
+# CHECK-L: Exception:<constructor Exception>
+Exception