From f31386d15d86cdce308348526c6a94900f5a8dab Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sb@m-labs.hk>
Date: Thu, 18 Dec 2014 11:13:50 +0800
Subject: [PATCH] py2llvm: len() support on lists

---
 artiq/py2llvm/ast_body.py |  4 ++--
 artiq/py2llvm/lists.py    | 10 ++++++++++
 artiq/test/full_stack.py  |  2 +-
 artiq/transforms/tools.py |  2 +-
 4 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/artiq/py2llvm/ast_body.py b/artiq/py2llvm/ast_body.py
index 7f67af79d..306ffb821 100644
--- a/artiq/py2llvm/ast_body.py
+++ b/artiq/py2llvm/ast_body.py
@@ -167,9 +167,9 @@ class Visitor:
 
     def _visit_expr_Call(self, node):
         fn = node.func.id
-        if fn in {"bool", "int", "int64", "round", "round64", "float"}:
+        if fn in {"bool", "int", "int64", "round", "round64", "float", "len"}:
             value = self.visit_expression(node.args[0])
-            return getattr(value, "o_"+fn)(self.builder)
+            return getattr(value, "o_" + fn)(self.builder)
         elif fn == "Fraction":
             r = fractions.VFraction()
             if self.builder is not None:
diff --git a/artiq/py2llvm/lists.py b/artiq/py2llvm/lists.py
index cd705f3be..d8f814ff0 100644
--- a/artiq/py2llvm/lists.py
+++ b/artiq/py2llvm/lists.py
@@ -1,6 +1,7 @@
 import llvmlite.ir as ll
 
 from artiq.py2llvm.values import VGeneric
+from artiq.py2llvm.base_types import VInt
 
 
 class VList(VGeneric):
@@ -40,6 +41,15 @@ class VList(VGeneric):
             ll.Constant(ll.IntType(32), 0)])
         builder.store(ll.Constant(ll.IntType(32), count), count_ptr)
 
+    def o_len(self, builder):
+        r = VInt()
+        if builder is not None:
+            count_ptr = builder.gep(self.llvm_value, [
+                ll.Constant(ll.IntType(32), 0),
+                ll.Constant(ll.IntType(32), 0)])
+            r.auto_store(builder, builder.load(count_ptr))
+        return r
+
     def o_subscript(self, index, builder):
         r = self.el_type.new()
         if builder is not None:
diff --git a/artiq/test/full_stack.py b/artiq/test/full_stack.py
index 8ef013f59..fd19ac8f6 100644
--- a/artiq/test/full_stack.py
+++ b/artiq/test/full_stack.py
@@ -61,7 +61,7 @@ class _Misc(AutoContext):
         self.inhomogeneous_units.append(Quantity(1000, "Hz"))
         self.inhomogeneous_units.append(Quantity(10, "s"))
         self.acc = 0
-        for i in range(5):
+        for i in range(len(self.al)):
             self.acc += self.al[i]
 
     @kernel
diff --git a/artiq/transforms/tools.py b/artiq/transforms/tools.py
index ddf69457c..098458bb0 100644
--- a/artiq/transforms/tools.py
+++ b/artiq/transforms/tools.py
@@ -9,7 +9,7 @@ embeddable_funcs = (
     core_language.delay, core_language.at, core_language.now,
     core_language.time_to_cycles, core_language.cycles_to_time,
     core_language.syscall,
-    range, bool, int, float, round,
+    range, bool, int, float, round, len,
     core_language.int64, core_language.round64,
     Fraction, units.Quantity, units.check_unit, core_language.EncodedException
 )