[Qemu-arm] [PATCH 01/67] decodetree: Allow !function with no input bits

[Richard Henderson]

With this, we can have the function return a value from the DisasContext.

Signed-off-by: Richard Henderson <address@hidden>
---
 scripts/decodetree.py             | 5 ++++-
 tests/decode/succ_function.decode | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)
 create mode 100644 tests/decode/succ_function.decode

diff --git a/scripts/decodetree.py b/scripts/decodetree.py
index d7a59d63ac..4259d87a95 100755
--- a/scripts/decodetree.py
+++ b/scripts/decodetree.py
@@ -195,7 +195,10 @@ class MultiField:
     """Class representing a compound instruction field"""
     def __init__(self, subs, mask):
         self.subs = subs
-        self.sign = subs[0].sign
+        if len(subs):
+            self.sign = subs[0].sign
+        else:
+            self.sign = 0
         self.mask = mask
 
     def __str__(self):
diff --git a/tests/decode/succ_function.decode 
b/tests/decode/succ_function.decode
new file mode 100644
index 0000000000..632a9de252
--- /dev/null
+++ b/tests/decode/succ_function.decode
@@ -0,0 +1,2 @@
+%foo  !function=foo
+foo   00000000000000000000000000000000 %foo
-- 
2.17.1