From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Thu, 14 Feb 2019 06:26:25 +0000 (+0000)
Subject: add b inf special case
X-Git-Tag: ls180-24jan2020~2028
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=541f086f5ba7e8d1084f1eae66a18bc5f4233bef;p=ieee754fpu.git

add b inf special case
---

diff --git a/src/add/nmigen_add_experiment.py b/src/add/nmigen_add_experiment.py
index 1a1189a7..ee4abf5a 100644
--- a/src/add/nmigen_add_experiment.py
+++ b/src/add/nmigen_add_experiment.py
@@ -133,6 +133,15 @@ class FPADD:
                           z[22].eq(1),      # mantissa top bit: 1
                           z[0:22].eq(0)     # mantissa rest: 0b0000...
                         ]
+                # if b is inf return inf
+                with m.Elif(b_e == 128):
+                    m.next = "put_z"
+                    m.d.sync += [
+                        z[31].eq(b_s),    # sign: b_s
+                        z[23:31].eq(255), # exp: 0b11111...
+                        z[0:23].eq(0)     # mantissa rest: 0b0000...
+                    ]
+
         return m
 
 """