mpir/mpn/x86_64w/atom/submul_1.asm
2012-11-25 22:33:07 +00:00

311 lines
8.2 KiB
NASM

; PROLOGUE(submul_1)
; Copyright 2006 Jason Worth Martin <jason.worth.martin@gmail.com>
;
; Copyright 2008, 2009 Brian Gladman
;
; This file is part of the GNU MP Library.
;
; The GNU MP Library is free software; you can redistribute it and/or
; modify it under the terms of the GNU Lesser General Public License as
; published by the Free Software Foundation; either version 2.1 of the
; License, or (at your option) any later version.
;
; The GNU MP Library is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
; Lesser General Public License for more details.
;
; You should have received a copy of the GNU Lesser General Public
; License along with the GNU MP Library; see the file COPYING.LIB. If
; not, write to the Free Software Foundation, Inc., 51 Franklin Street,
; Fifth Floor, Boston, MA 02110-1301, USA.
;
; CREDITS
;
; The code used here is derived from that provided by ct35z at:
;
; http://www.geocities.jp/ct35z/gmp-core2-en.html
;
; This code is based largely on Pierrick Gaudry's excellent assembly
; support for the AMD64 architecture. (Note that Intel64 and AMD64,
; while using the same instruction set, have very different
; microarchitectures. So, this code performs very poorly on AMD64
; machines even though it is near-optimal on Intel64.)
;
; Roger Golliver works for Intel and provided insightful improvements
; particularly in using the "lea" instruction to perform additions
; and register-to-register moves.
;
; Jason Worth Martin's excellent assembly support for the Intel64
; architecture has been used where appropriate.
;
; Eric Bainville has a brilliant exposition of optimizing arithmetic for
; AMD64 (http://www.bealto.it). I adapted many of the ideas he
; describes to Intel64.
;
; Agner Fog is a demigod in the x86 world. If you are reading assembly
; code files and you haven't heard of Agner Fog, then take a minute to
; look over his software optimization manuals (http://www.agner.org/).
; They are superb.
;
; Adapted for use with VC++ and YASM using a special mode in which NASM
; preprocessing is used with AT&T assembler syntax. I am very grateful
; for the support that Peter Johnson (one of the authors of YASM) has
; provided in getting this special YASM mode working. Without his
; support this port would have been a great deal more difficult.
;
; The principle issues that I have had to address is the difference
; between GCC and MSVC in their register saving and parameter passing
; conventions. Registers that have to be preserved across function
; calls are:
;
; GCC: rbx, rbp, r12..r15
; MSVC: rsi, rdi, rbx, rbp, r12..r15 xmm6..xmm15
;
; Parameter passing conventions for non floating point parameters:
;
; function( GCC MSVC
; p1, rdi rcx
; p2, rsi rdx
; p3, rdx r8
; p4, rcx r9
; p5, r8 [rsp+40]
; p6, r9 [rsp+48]
;
; Care must be taken with 32-bit values in 64-bit register or on the
; stack because the upper 32-bits of such parameters are undefined.
;
; Brian Gladman
;
; Intel64 mpn_addmul_1 -- Multiply a limb vector with a limb and
; add the result to a second limb vector.
;
; Calculate src[size] multiplied by mult[1] and add to /subtract from dst[size] and
; return the carry or borrow from the top of the result
;
; BPL is bytes per limb, which is 8 in the 64-bit code here
; mp_limb_t mpn_submul_1(mp_ptr, mp_ptr, mp_size_t, mp_limb_t)
; mp_limb_t mpn_declsh_n(mp_ptr, mp_ptr, mp_size_t, mp_uint)
; rax rdi rsi rdx rcx
; rax rcx rdx r8 r9
;
%define BPL 8
%define UNROLL_EXPONENT 4
%define UNROLL_SIZE (1 << UNROLL_EXPONENT)
%define UNROLL_MASK (UNROLL_SIZE - 1)
%define ADDR(p,i,d) (d*BPL)(p, i, BPL)
; Register Usage
; -------- -----
; rax low word from mul
; rbx
; rcx s2limb
; rdx high word from mul
; rsi s1p
; rdi rp
; rbp Base Pointer
; rsp Stack Pointer
; r8 A_x
; r9 A_y
; r10 A_z
; r11 B_x
; r12 B_y
; r13 B_z
; r14 temp
; r15 index
%include "yasm_mac.inc"
%define reg_save_list rsi, rdi, r12, r13, r14, r15
%define s2limb rcx
%define s1p rsi
%define rp rdi
%define a_x r8
%define a_y r9
%define a_z r10
%define b_x r11
%define b_y r12
%define b_z r13
%define temp r14
%define index r15
LEAF_PROC mpn_submul_1
xor a_z, a_z
jmp entry
LEAF_PROC mpn_submul_1c
mov a_z, [rsp+0x28]
entry:
FRAME_PROC ?mpn_atom_submul, 0, reg_save_list
mov rdi, rcx
mov rsi, rdx
xor rdx, rdx
mov rdx, r8
mov rcx, r9
lea s1p, [s1p+rdx*8]
lea rp, [rp+rdx*8]
xor index, index
sub index, rdx
cmp rdx, 4
jge .6
lea rax, [rel .1]
add rax, [rax+rdx*8]
jmp rax
xalign 8
.1: dq .2 - .1
dq .3 - .1
dq .4 - .1
dq .5 - .1
.2: mov rax, a_z
EXIT_PROC reg_save_list
.3: mov rax, [s1p+index*8]
mul s2limb
add rax, a_z
adc rdx, 0
mov a_z, [rp+index*8]
sub a_z, rax
mov rax, 0
mov [rp+index*8], a_z
adc rax, rdx
EXIT_PROC reg_save_list
.4: mov rax, [s1p+index*8]
mul s2limb
add rax, a_z
adc rdx, 0
mov a_z, [rp+index*8]
mov a_x, rax
mov a_y, rdx
mov rax, [s1p+index*8+8]
mul s2limb
mov b_z, [rp+index*8+8]
sub a_z, a_x
adc rax, a_y
mov [rp+index*8], a_z
adc rdx, 0
sub b_z, rax
mov rax, 0
mov [rp+index*8+8], b_z
adc rax, rdx
EXIT_PROC reg_save_list
.5: mov rax, [s1p+index*8]
mul s2limb
add rax, a_z
adc rdx, 0
mov a_z, [rp+index*8]
mov a_x, rax
mov a_y, rdx
mov rax, [s1p+index*8+8]
mul s2limb
mov b_z, [rp+index*8+8]
mov b_x, rax
mov b_y, rdx
mov rax, [s1p+index*8+16]
mul s2limb
sub a_z, a_x
adc b_x, a_y
mov [rp+index*8], a_z
mov a_z, [rp+index*8+16]
adc b_y, 0
sub b_z, b_x
adc rax, b_y
mov [rp+index*8+8], b_z
adc rdx, 0
sub a_z, rax
mov rax, 0
mov [rp+index*8+16], a_z
adc rax, rdx
EXIT_PROC reg_save_list
.6: mov temp, rdx
test rdx, 1
jz .7
mov rax, [s1p+index*8]
mul s2limb
add rax, a_z
adc rdx, 0
mov a_z, [rp+index*8]
mov a_x, rax
mov a_y, rdx
mov rax, [s1p+index*8+8]
mul s2limb
mov b_z, [rp+index*8+8]
mov b_x, rax
mov b_y, rdx
jmp .8
.7: mov rax, [s1p+index*8]
mul s2limb
add rax, a_z
adc rdx, 0
mov b_z, [rp+index*8]
mov b_x, rax
mov b_y, rdx
mov rax, [s1p+index*8+8]
mul s2limb
mov a_z, [rp+index*8+8]
mov a_x, rax
mov a_y, rdx
.8: sub temp, 4
and temp, UNROLL_MASK
inc temp
mov rax, (.10 - .9) >> UNROLL_EXPONENT
mul temp
lea rdx, [rel .10]
sub rdx, rax
mov rax, [s1p+index*8+16]
lea index, [index+temp+3-UNROLL_SIZE]
jmp rdx
%macro seq_1 7
mul s2limb
%7 %3, %1
lea %1, [rax]
mov rax, [byte s1p+index*8+8*%6]
adc %4, %2
mov [byte rp+index*8+8*(%6-3)], %3
mov %3, [byte rp+index*8+8*(%6-1)]
lea %2, [rdx]
adc %5, 0
%endmacro
xalign 16
.9:
%assign i 0
%rep 16
%if (i & 1)
seq_1 b_x, b_y, b_z, a_x, a_y, i, sub
%else
seq_1 a_x, a_y, a_z, b_x, b_y, i, sub
%endif
%assign i i + 1
%endrep
.10:add index, UNROLL_SIZE
jnz .9
.11:mul s2limb
sub a_z, a_x
mov [rp+index*8-24], a_z
mov a_z, [rp+index*8-8]
adc b_x, a_y
adc b_y, 0
sub b_z, b_x
mov [rp+index*8-16], b_z
adc rax, b_y
adc rdx, 0
sub a_z, rax
mov rax, 0
mov [rp+index*8-8], a_z
adc rax, rdx
.12:END_PROC reg_save_list
end