From: Jacob Lifshay <programmerjake@gmail.com>
Date: Fri, 18 Mar 2022 04:56:18 +0000 (-0700)
Subject: delete redundant sections
X-Git-Tag: opf_rfc_ls005_v1~3014
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0324e31625e68283847bc7d599060e1e3c31a7ff;p=libreriscv.git

delete redundant sections
---

diff --git a/openpower/sv/bitmanip.mdwn b/openpower/sv/bitmanip.mdwn
index 44d99c99d..e8ceb8b7f 100644
--- a/openpower/sv/bitmanip.mdwn
+++ b/openpower/sv/bitmanip.mdwn
@@ -826,112 +826,6 @@ term = (RC)
 (RS) = gfpmsubr(factor1, factor2, term)
 ```
 
-## Twin Butterfly (Tukey-Cooley) Mul-add-sub
-
-used in combination with SV FFT REMAP to perform
-a full NTT in-place. possible by having 3-in 2-out,
-to avoid the need for a temp register.  RS is written
-to as well as RT.
-
-    gffmadd  RT,RA,RC,RB (Rc=0)
-    gffmadd. RT,RA,RC,RB (Rc=1)
-
-Pseudo-code:
-
-    RT <- GFADD(GFMUL(RA, RC), RB))
-    RS <- GFADD(GFMUL(RA, RC), RB))
-
-
-## Multiply
-
-with the modulo and degree being in an SPR, multiply can be identical
-equivalent to standard integer add
-
-    RS = GFMUL(RA, RB)
-
-| 0.5|6.10|11.15|16.20|21.25| 26..30 |31|
-| -- | -- | --- | --- | --- | ------ |--|
-| NN | RT | RA  | RB  |11000|  01110 |Rc|
-
-
-
-```
-from functools import reduce
-
-def gf_degree(a) :
-  res = 0
-  a >>= 1
-  while (a != 0) :
-    a >>= 1;
-    res += 1;
-  return res
-
-# constants used in the multGF2 function
-mask1 = mask2 = polyred = None
-
-def setGF2(irPoly):
-    """Define parameters of binary finite field GF(2^m)/g(x)
-       - irPoly: coefficients of irreducible polynomial g(x)
-    """
-    # degree: extension degree of binary field
-    degree = gf_degree(irPoly)
-
-    def i2P(sInt):
-        """Convert an integer into a polynomial"""
-        return [(sInt >> i) & 1
-                for i in reversed(range(sInt.bit_length()))]    
-    
-    global mask1, mask2, polyred
-    mask1 = mask2 = 1 << degree
-    mask2 -= 1
-    polyred = reduce(lambda x, y: (x << 1) + y, i2P(irPoly)[1:])
-        
-def multGF2(p1, p2):
-    """Multiply two polynomials in GF(2^m)/g(x)"""
-    p = 0
-    while p2:
-        # standard long-multiplication: check LSB and add
-        if p2 & 1:
-            p ^= p1
-        p1 <<= 1
-        # standard modulo: check MSB and add polynomial
-        if p1 & mask1:
-            p1 ^= polyred
-        p2 >>= 1
-    return p & mask2
-
-if __name__ == "__main__":
-  
-    # Define binary field GF(2^3)/x^3 + x + 1
-    setGF2(0b1011) # degree 3
-
-    # Evaluate the product (x^2 + x + 1)(x^2 + 1)
-    print("{:02x}".format(multGF2(0b111, 0b101)))
-    
-    # Define binary field GF(2^8)/x^8 + x^4 + x^3 + x + 1
-    # (used in the Advanced Encryption Standard-AES)
-    setGF2(0b100011011) # degree 8
-    
-    # Evaluate the product (x^7)(x^7 + x + 1)
-    print("{:02x}".format(multGF2(0b10000000, 0b10000011)))
-```
-
-## carryless Twin Butterfly (Tukey-Cooley) Mul-add-sub
-
-used in combination with SV FFT REMAP to perform
-a full NTT in-place. possible by having 3-in 2-out,
-to avoid the need for a temp register.  RS is written
-to as well as RT.
-
-    clfmadd  RT,RA,RC,RB (Rc=0)
-    clfmadd. RT,RA,RC,RB (Rc=1)
-
-Pseudo-code:
-
-    RT <- CLMUL(RA, RC) ^ RB
-    RS <- CLMUL(RA, RC) ^ RB
-
-
 # bitmatrix
 
 ```