From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Sun, 28 Apr 2019 13:44:49 +0000 (+0100)
Subject: add some functions copied from unit_test_single for mantissa/exponent handling
X-Git-Tag: ls180-24jan2020~1158
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=da01094c82c4569fe529664ccbb044cca0c19e63;p=ieee754fpu.git

add some functions copied from unit_test_single for mantissa/exponent handling
---

diff --git a/src/add/fsqrt.py b/src/add/fsqrt.py
index 3a8f8905..72850314 100644
--- a/src/add/fsqrt.py
+++ b/src/add/fsqrt.py
@@ -45,6 +45,21 @@ def sqrt(num):
     return Q
 
 
+# grabbed these from unit_test_single (convenience, this is just experimenting)
+
+def get_mantissa(x):
+    return 0x7fffff & x
+
+def get_exponent(x):
+    return ((x & 0x7f800000) >> 23) - 127
+
+def set_exponent(x, e):
+    return (x & ~0x7f800000) | ((e+127) << 23)
+
+def get_sign(x):
+    return ((x & 0x80000000) >> 31)
+
+
 def main(mantissa, exponent):
     if exponent & 1 != 0:
         return sqrt(mantissa << 1), # shift mantissa up