Botan::word3< W > Class Template Reference

#include <mp_asmi.h>

Public Member Functions
constexpr void	add (W x)
constexpr W	extract ()
constexpr W	monty_step (W p0, W p_dash)
constexpr W	monty_step_pdash1 ()
constexpr void	mul (W x, W y)
constexpr void	mul_x2 (W x, W y)
constexpr	word3 ()

Detailed Description

template<WordType W>
class Botan::word3< W >

Helper for 3-word accumulators

A number of algorithms especially Comba multiplication and Montgomery reduction can take advantage of wide accumulators, which consume inputs via addition with outputs extracted from the low bits.

Definition at line 596 of file mp_asmi.h.

Constructor & Destructor Documentation

word3()

template<WordType W>

Botan::word3< W >::word3 ( )

inlineconstexpr

Definition at line 635 of file mp_asmi.h.

                        {
         m_w2 = 0;
         m_w1 = 0;
         m_w0 = 0;
      }

Member Function Documentation

add()

template<WordType W>

void Botan::word3< W >::add ( W x )

inlineconstexpr

Definition at line 645 of file mp_asmi.h.

{ word3_add(&m_w2, &m_w1, &m_w0, x); }

References Botan::word3_add().

Referenced by Botan::bigint_monty_redc_16(), Botan::bigint_monty_redc_24(), Botan::bigint_monty_redc_32(), Botan::bigint_monty_redc_4(), Botan::bigint_monty_redc_6(), Botan::bigint_monty_redc_8(), and Botan::bigint_monty_redc_generic().

extract()

template<WordType W>

W Botan::word3< W >::extract ( )

inlineconstexpr

Definition at line 647 of file mp_asmi.h.

                                   {
         W r = m_w0;
         m_w0 = m_w1;
         m_w1 = m_w2;
         m_w2 = 0;
         return r;
      }

Referenced by Botan::bigint_comba_mul16(), Botan::bigint_comba_mul24(), Botan::bigint_comba_mul4(), Botan::bigint_comba_mul6(), Botan::bigint_comba_mul7(), Botan::bigint_comba_mul8(), Botan::bigint_comba_mul9(), Botan::bigint_comba_sqr16(), Botan::bigint_comba_sqr24(), Botan::bigint_comba_sqr4(), Botan::bigint_comba_sqr6(), Botan::bigint_comba_sqr7(), Botan::bigint_comba_sqr8(), Botan::bigint_comba_sqr9(), Botan::bigint_monty_redc_16(), Botan::bigint_monty_redc_24(), Botan::bigint_monty_redc_32(), Botan::bigint_monty_redc_4(), Botan::bigint_monty_redc_6(), Botan::bigint_monty_redc_8(), Botan::bigint_monty_redc_generic(), Botan::comba_mul(), and Botan::comba_sqr().

monty_step()

template<WordType W>

W Botan::word3< W >::monty_step ( W p0, W p_dash )

inlineconstexpr

Definition at line 655 of file mp_asmi.h.

                                                    {
         W r = m_w0 * p_dash;
         mul(r, p0);
         m_w0 = m_w1;
         m_w1 = m_w2;
         m_w2 = 0;
         return r;
      }

References Botan::word3< W >::mul().

Referenced by Botan::bigint_monty_redc_16(), Botan::bigint_monty_redc_24(), Botan::bigint_monty_redc_32(), Botan::bigint_monty_redc_4(), Botan::bigint_monty_redc_6(), Botan::bigint_monty_redc_8(), and Botan::bigint_monty_redc_generic().

monty_step_pdash1()

template<WordType W>

W Botan::word3< W >::monty_step_pdash1 ( )

inlineconstexpr

Definition at line 664 of file mp_asmi.h.

                                             {
         // If p_dash == 1 then p[0] = -1 and everything simplifies
         const W r = m_w0;
         m_w0 += m_w1;
         m_w1 = m_w2 + (m_w0 < m_w1);
         m_w2 = 0;
         return r;
      }

mul()

template<WordType W>

void Botan::word3< W >::mul ( W x, W y )

inlineconstexpr

Definition at line 641 of file mp_asmi.h.

{ word3_muladd(&m_w2, &m_w1, &m_w0, x, y); }

References Botan::word3_muladd().

Referenced by Botan::bigint_comba_mul16(), Botan::bigint_comba_mul24(), Botan::bigint_comba_mul4(), Botan::bigint_comba_mul6(), Botan::bigint_comba_mul7(), Botan::bigint_comba_mul8(), Botan::bigint_comba_mul9(), Botan::bigint_comba_sqr16(), Botan::bigint_comba_sqr24(), Botan::bigint_comba_sqr4(), Botan::bigint_comba_sqr6(), Botan::bigint_comba_sqr7(), Botan::bigint_comba_sqr8(), Botan::bigint_comba_sqr9(), Botan::bigint_monty_redc_16(), Botan::bigint_monty_redc_24(), Botan::bigint_monty_redc_32(), Botan::bigint_monty_redc_4(), Botan::bigint_monty_redc_6(), Botan::bigint_monty_redc_8(), Botan::bigint_monty_redc_generic(), Botan::comba_mul(), Botan::comba_sqr(), and Botan::word3< W >::monty_step().

mul_x2()

template<WordType W>

void Botan::word3< W >::mul_x2 ( W x, W y )

inlineconstexpr

Definition at line 643 of file mp_asmi.h.

{ word3_muladd_2(&m_w2, &m_w1, &m_w0, x, y); }

References Botan::word3_muladd_2().

Referenced by Botan::bigint_comba_sqr16(), Botan::bigint_comba_sqr24(), Botan::bigint_comba_sqr4(), Botan::bigint_comba_sqr6(), Botan::bigint_comba_sqr7(), Botan::bigint_comba_sqr8(), and Botan::bigint_comba_sqr9().

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The documentation for this class was generated from the following file:

• src/lib/math/mp/mp_asmi.h