From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Tue, 19 Feb 2019 08:05:29 +0000 (+0000)
Subject: whoops FP16 mantissa off-by-one
X-Git-Tag: ls180-24jan2020~1871
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=5c0058aba5b26ccf44564b4cc490a08323786983;p=ieee754fpu.git

whoops FP16 mantissa off-by-one
---

diff --git a/src/add/fpbase.py b/src/add/fpbase.py
index 5c303046..e6222c2f 100644
--- a/src/add/fpbase.py
+++ b/src/add/fpbase.py
@@ -70,7 +70,7 @@ class FPNum:
     """
     def __init__(self, width, m_extra=True):
         self.width = width
-        m_width = {16: 12, 32: 24, 64: 53}[width] # 1 extra bit (overflow)
+        m_width = {16: 11, 32: 24, 64: 53}[width] # 1 extra bit (overflow)
         e_width = {16: 7,  32: 10, 64: 13}[width] # 2 extra bits (overflow)
         e_max = 1<<(e_width-3)
         self.rmw = m_width # real mantissa width (not including extras)