/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
 */

#include <linux/linkage.h>

ENTRY_CFI(strcmp)
        or      r2, r0, r1
        bmsk_s  r2, r2, 1
        brne    r2, 0, @.Lcharloop

;;; s1 and s2 are word aligned
        ld.ab   r2, [r0, 4]

        mov_s   r12, 0x01010101
        ror     r11, r12
        .align  4
.LwordLoop:
        ld.ab   r3, [r1, 4]
        ;; Detect NULL char in str1
        sub     r4, r2, r12
        ld.ab   r5, [r0, 4]
        bic     r4, r4, r2
        and     r4, r4, r11
        brne.d.nt       r4, 0, .LfoundNULL
        ;; Check if the read locations are the same
        cmp     r2, r3
        beq.d   .LwordLoop
        mov.eq  r2, r5

        ;; A match is found, spot it out
#ifdef __LITTLE_ENDIAN__
        swape   r3, r3
        mov_s   r0, 1
        swape   r2, r2
#else
        mov_s   r0, 1
#endif
        cmp_s   r2, r3
        j_s.d   [blink]
        bset.lo r0, r0, 31

        .align 4
.LfoundNULL:
#ifdef __BIG_ENDIAN__
        swape   r4, r4
        swape   r2, r2
        swape   r3, r3
#endif
        ;; Find null byte
        ffs     r0, r4
        bmsk    r2, r2, r0
        bmsk    r3, r3, r0
        swape   r2, r2
        swape   r3, r3
        ;; make the return value
        sub.f   r0, r2, r3
        mov.hi  r0, 1
        j_s.d   [blink]
        bset.lo r0, r0, 31

        .align 4
.Lcharloop:
        ldb.ab  r2, [r0, 1]
        ldb.ab  r3, [r1, 1]
        nop
        breq    r2, 0, .Lcmpend
        breq    r2, r3, .Lcharloop

        .align 4
.Lcmpend:
        j_s.d   [blink]
        sub     r0, r2, r3
END_CFI(strcmp)