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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# ------------------------------------------------------------------------
#
# Implementation of s_mpv_mul_set_vec which exploits
# the 64X64->128 bit unsigned multiply instruction.
#
# ------------------------------------------------------------------------
# r = a * digit, r and a are vectors of length len
# returns the carry digit
# r and a are 64 bit aligned.
#
# uint64_t
# s_mpv_mul_set_vec64(uint64_t *r, uint64_t *a, int len, uint64_t digit)
#
.text; .align 16; .globl s_mpv_mul_set_vec64;
#ifdef DARWIN
#define s_mpv_mul_set_vec64 _s_mpv_mul_set_vec64
.private_extern s_mpv_mul_set_vec64
s_mpv_mul_set_vec64:
#else
.type s_mpv_mul_set_vec64, @function; s_mpv_mul_set_vec64:
#endif
xorq %rax, %rax # if (len == 0) return (0)
testq %rdx, %rdx
jz .L17
movq %rdx, %r8 # Use r8 for len; %rdx is used by mul
xorq %r9, %r9 # cy = 0
.L15:
cmpq $8, %r8 # 8 - len
jb .L16
movq 0(%rsi), %rax # rax = a[0]
movq 8(%rsi), %r11 # prefetch a[1]
mulq %rcx # p = a[0] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 0(%rdi) # r[0] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 16(%rsi), %r11 # prefetch a[2]
mulq %rcx # p = a[1] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 8(%rdi) # r[1] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 24(%rsi), %r11 # prefetch a[3]
mulq %rcx # p = a[2] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 16(%rdi) # r[2] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 32(%rsi), %r11 # prefetch a[4]
mulq %rcx # p = a[3] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 24(%rdi) # r[3] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 40(%rsi), %r11 # prefetch a[5]
mulq %rcx # p = a[4] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 32(%rdi) # r[4] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 48(%rsi), %r11 # prefetch a[6]
mulq %rcx # p = a[5] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 40(%rdi) # r[5] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 56(%rsi), %r11 # prefetch a[7]
mulq %rcx # p = a[6] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 48(%rdi) # r[6] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
mulq %rcx # p = a[7] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 56(%rdi) # r[7] = lo(p)
movq %rdx, %r9 # cy = hi(p)
addq $64, %rsi
addq $64, %rdi
subq $8, %r8
jz .L17
jmp .L15
.L16:
movq 0(%rsi), %rax
mulq %rcx # p = a[0] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 0(%rdi) # r[0] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 8(%rsi), %rax
mulq %rcx # p = a[1] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 8(%rdi) # r[1] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 16(%rsi), %rax
mulq %rcx # p = a[2] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 16(%rdi) # r[2] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 24(%rsi), %rax
mulq %rcx # p = a[3] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 24(%rdi) # r[3] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 32(%rsi), %rax
mulq %rcx # p = a[4] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 32(%rdi) # r[4] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 40(%rsi), %rax
mulq %rcx # p = a[5] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 40(%rdi) # r[5] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
movq 48(%rsi), %rax
mulq %rcx # p = a[6] * digit
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 48(%rdi) # r[6] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L17
.L17:
movq %r9, %rax
ret
#ifndef DARWIN
.size s_mpv_mul_set_vec64, .-s_mpv_mul_set_vec64
#endif
# ------------------------------------------------------------------------
#
# Implementation of s_mpv_mul_add_vec which exploits
# the 64X64->128 bit unsigned multiply instruction.
#
# ------------------------------------------------------------------------
# r += a * digit, r and a are vectors of length len
# returns the carry digit
# r and a are 64 bit aligned.
#
# uint64_t
# s_mpv_mul_add_vec64(uint64_t *r, uint64_t *a, int len, uint64_t digit)
#
.text; .align 16; .globl s_mpv_mul_add_vec64;
#ifdef DARWIN
#define s_mpv_mul_add_vec64 _s_mpv_mul_add_vec64
.private_extern s_mpv_mul_add_vec64
s_mpv_mul_add_vec64:
#else
.type s_mpv_mul_add_vec64, @function; s_mpv_mul_add_vec64:
#endif
xorq %rax, %rax # if (len == 0) return (0)
testq %rdx, %rdx
jz .L27
movq %rdx, %r8 # Use r8 for len; %rdx is used by mul
xorq %r9, %r9 # cy = 0
.L25:
cmpq $8, %r8 # 8 - len
jb .L26
movq 0(%rsi), %rax # rax = a[0]
movq 0(%rdi), %r10 # r10 = r[0]
movq 8(%rsi), %r11 # prefetch a[1]
mulq %rcx # p = a[0] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[0]
movq 8(%rdi), %r10 # prefetch r[1]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 0(%rdi) # r[0] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 16(%rsi), %r11 # prefetch a[2]
mulq %rcx # p = a[1] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[1]
movq 16(%rdi), %r10 # prefetch r[2]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 8(%rdi) # r[1] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 24(%rsi), %r11 # prefetch a[3]
mulq %rcx # p = a[2] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[2]
movq 24(%rdi), %r10 # prefetch r[3]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 16(%rdi) # r[2] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 32(%rsi), %r11 # prefetch a[4]
mulq %rcx # p = a[3] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[3]
movq 32(%rdi), %r10 # prefetch r[4]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 24(%rdi) # r[3] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 40(%rsi), %r11 # prefetch a[5]
mulq %rcx # p = a[4] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[4]
movq 40(%rdi), %r10 # prefetch r[5]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 32(%rdi) # r[4] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 48(%rsi), %r11 # prefetch a[6]
mulq %rcx # p = a[5] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[5]
movq 48(%rdi), %r10 # prefetch r[6]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 40(%rdi) # r[5] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
movq 56(%rsi), %r11 # prefetch a[7]
mulq %rcx # p = a[6] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[6]
movq 56(%rdi), %r10 # prefetch r[7]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 48(%rdi) # r[6] = lo(p)
movq %rdx, %r9 # cy = hi(p)
movq %r11, %rax
mulq %rcx # p = a[7] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[7]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 56(%rdi) # r[7] = lo(p)
movq %rdx, %r9 # cy = hi(p)
addq $64, %rsi
addq $64, %rdi
subq $8, %r8
jz .L27
jmp .L25
.L26:
movq 0(%rsi), %rax
movq 0(%rdi), %r10
mulq %rcx # p = a[0] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[0]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 0(%rdi) # r[0] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 8(%rsi), %rax
movq 8(%rdi), %r10
mulq %rcx # p = a[1] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[1]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 8(%rdi) # r[1] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 16(%rsi), %rax
movq 16(%rdi), %r10
mulq %rcx # p = a[2] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[2]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 16(%rdi) # r[2] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 24(%rsi), %rax
movq 24(%rdi), %r10
mulq %rcx # p = a[3] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[3]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 24(%rdi) # r[3] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 32(%rsi), %rax
movq 32(%rdi), %r10
mulq %rcx # p = a[4] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[4]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 32(%rdi) # r[4] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 40(%rsi), %rax
movq 40(%rdi), %r10
mulq %rcx # p = a[5] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[5]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 40(%rdi) # r[5] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
movq 48(%rsi), %rax
movq 48(%rdi), %r10
mulq %rcx # p = a[6] * digit
addq %r10, %rax
adcq $0, %rdx # p += r[6]
addq %r9, %rax
adcq $0, %rdx # p += cy
movq %rax, 48(%rdi) # r[6] = lo(p)
movq %rdx, %r9 # cy = hi(p)
decq %r8
jz .L27
.L27:
movq %r9, %rax
ret
#ifndef DARWIN
.size s_mpv_mul_add_vec64, .-s_mpv_mul_add_vec64
# Magic indicating no need for an executable stack
.section .note.GNU-stack, "", @progbits
.previous
#endif