/*

 * Copyright (c) 2016, Linaro Ltd. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

        .global _Copy_conjoint_words

        .global _Copy_disjoint_words

s       .req    x0

d       .req    x1

count   .req    x2

t0      .req    x3

t1      .req    x4

t2      .req    x5

t3      .req    x6

t4      .req    x7

t5      .req    x8

t6      .req    x9

t7      .req    x10

        .align  6

_Copy_disjoint_words:

        // Ensure 2 word aligned

        tbz     s, #3, fwd_copy_aligned

        ldr     t0, [s], #8

        str     t0, [d], #8

        sub     count, count, #1

fwd_copy_aligned:

        // Bias s & d so we only pre index on the last copy

        sub     s, s, #16

        sub     d, d, #16

        ldp     t0, t1, [s, #16]

        ldp     t2, t3, [s, #32]

        ldp     t4, t5, [s, #48]

        ldp     t6, t7, [s, #64]!

        subs    count, count, #16

        blo     fwd_copy_drain

fwd_copy_again:

        prfm    pldl1keep, [s, #256]

        stp     t0, t1, [d, #16]

        ldp     t0, t1, [s, #16]

        stp     t2, t3, [d, #32]

        ldp     t2, t3, [s, #32]

        stp     t4, t5, [d, #48]

        ldp     t4, t5, [s, #48]

        stp     t6, t7, [d, #64]!

        ldp     t6, t7, [s, #64]!

        subs    count, count, #8

        bhs     fwd_copy_again

fwd_copy_drain:

        stp     t0, t1, [d, #16]

        stp     t2, t3, [d, #32]

        stp     t4, t5, [d, #48]

        stp     t6, t7, [d, #64]!

        // count is now -8..-1 for 0..7 words to copy

        adr     t0, 0f

        add     t0, t0, count, lsl #5

        br      t0

        .align  5

        ret                             // -8 == 0 words

        .align  5

        ldr     t0, [s, #16]            // -7 == 1 word

        str     t0, [d, #16]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -6 = 2 words

        stp     t0, t1, [d, #16]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -5 = 3 words

        ldr     t2, [s, #32]

        stp     t0, t1, [d, #16]

        str     t2, [d, #32]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -4 = 4 words

        ldp     t2, t3, [s, #32]

        stp     t0, t1, [d, #16]

        stp     t2, t3, [d, #32]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -3 = 5 words

        ldp     t2, t3, [s, #32]

        ldr     t4, [s, #48]

        stp     t0, t1, [d, #16]

        stp     t2, t3, [d, #32]

        str     t4, [d, #48]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -2 = 6 words

        ldp     t2, t3, [s, #32]

        ldp     t4, t5, [s, #48]

        stp     t0, t1, [d, #16]

        stp     t2, t3, [d, #32]

        stp     t4, t5, [d, #48]

        ret

        .align  5

        ldp     t0, t1, [s, #16]        // -1 = 7 words

        ldp     t2, t3, [s, #32]

        ldp     t4, t5, [s, #48]

        ldr     t6, [s, #64]

        stp     t0, t1, [d, #16]

        stp     t2, t3, [d, #32]

        stp     t4, t5, [d, #48]

        str     t6, [d, #64]

        // Is always aligned here, code for 7 words is one instruction

        // too large so it just falls through.

        .align  5

0:

        ret

        .align  6

_Copy_conjoint_words:

        sub     t0, d, s

        cmp     t0, count, lsl #3

        bhs     _Copy_disjoint_words

        add     s, s, count, lsl #3

        add     d, d, count, lsl #3

        // Ensure 2 word aligned

        tbz     s, #3, bwd_copy_aligned

        ldr     t0, [s, #-8]!

        str     t0, [d, #-8]!

        sub     count, count, #1

bwd_copy_aligned:

        ldp     t0, t1, [s, #-16]

        ldp     t2, t3, [s, #-32]

        ldp     t4, t5, [s, #-48]

        ldp     t6, t7, [s, #-64]!

        subs    count, count, #16

        blo     bwd_copy_drain

bwd_copy_again:

        prfm    pldl1keep, [s, #-256]

        stp     t0, t1, [d, #-16]

        ldp     t0, t1, [s, #-16]

        stp     t2, t3, [d, #-32]

        ldp     t2, t3, [s, #-32]

        stp     t4, t5, [d, #-48]

        ldp     t4, t5, [s, #-48]

        stp     t6, t7, [d, #-64]!

        ldp     t6, t7, [s, #-64]!

        subs    count, count, #8

        bhs     bwd_copy_again

bwd_copy_drain:

        stp     t0, t1, [d, #-16]

        stp     t2, t3, [d, #-32]

        stp     t4, t5, [d, #-48]

        stp     t6, t7, [d, #-64]!

        // count is now -8..-1 for 0..7 words to copy

        adr     t0, 0f

        add     t0, t0, count, lsl #5

        br      t0

        .align  5

        ret                             // -8 == 0 words

        .align  5

        ldr     t0, [s, #-8]            // -7 == 1 word

        str     t0, [d, #-8]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -6 = 2 words

        stp     t0, t1, [d, #-16]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -5 = 3 words

        ldr     t2, [s, #-24]

        stp     t0, t1, [d, #-16]

        str     t2, [d, #-24]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -4 = 4 words

        ldp     t2, t3, [s, #-32]

        stp     t0, t1, [d, #-16]

        stp     t2, t3, [d, #-32]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -3 = 5 words

        ldp     t2, t3, [s, #-32]

        ldr     t4, [s, #-40]

        stp     t0, t1, [d, #-16]

        stp     t2, t3, [d, #-32]

        str     t4, [d, #-40]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -2 = 6 words

        ldp     t2, t3, [s, #-32]

        ldp     t4, t5, [s, #-48]

        stp     t0, t1, [d, #-16]

        stp     t2, t3, [d, #-32]

        stp     t4, t5, [d, #-48]

        ret

        .align  5

        ldp     t0, t1, [s, #-16]       // -1 = 7 words

        ldp     t2, t3, [s, #-32]

        ldp     t4, t5, [s, #-48]

        ldr     t6, [s, #-56]

        stp     t0, t1, [d, #-16]

        stp     t2, t3, [d, #-32]

        stp     t4, t5, [d, #-48]

        str     t6, [d, #-56]

        // Is always aligned here, code for 7 words is one instruction

        // too large so it just falls through.

        .align  5

0:

        ret