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#define ASSEMBLER

#include "common.h"

#define N     $r4
#define X     $r5
#define INCX  $r6

#define I     $r12
#define TEMP  $r13

#define VM0 $xr0
#define VM1 $xr1
#define VM2 $xr2
#define VX0 $xr3
#define VX1 $xr4
#define VX2 $xr5
#define VX3 $xr6

#define t1 $r14
#define t2 $r15
#define t3 $r16
#define t4 $r17

    PROLOGUE

#ifdef F_INTERFACE
    LDINT   N,     0(N)
    LDINT   INCX,  0(INCX)
#endif

    bge $r0, N, .L999
    bge $r0, INCX, .L999
    li.d TEMP, 1
    slli.d TEMP, TEMP, BASE_SHIFT
    slli.d INCX, INCX, BASE_SHIFT
#ifdef DOUBLE
    xvldrepl.d VM0, X, 0
#else
    xvldrepl.w VM0, X, 0
#endif
    bne INCX, TEMP, .L20

    srai.d I, N, 4
    bge $r0, I, .L11
    .align 3

.L10:
#ifdef DOUBLE
    xvld VX0, X, 0
    xvld VX1, X, 32
    xvld VX2, X, 64
    xvld VX3, X, 96
    addi.d I, I, -1
    addi.d X, X, 128
    XVFMAX    VM1, VX0, VX1
    XVFMAX    VM2, VX2, VX3
    XVFMAX    VM0, VM0, VM1
    XVFMAX    VM0, VM0, VM2
#else
    xvld VX0, X, 0
    xvld VX1, X, 32
    addi.d I, I, -1
    addi.d X, X, 64
    XVFMAX    VM1, VX0, VX1
    XVFMAX    VM0, VM0, VM1
#endif
    blt $r0, I, .L10

#ifdef DOUBLE
    xvrepl128vei.d VX0, VM0, 0
    xvrepl128vei.d VX1, VM0, 1
    XVFMAX    VM0, VX0, VX1
#else
    xvrepl128vei.w VX0, VM0, 0
    xvrepl128vei.w VX1, VM0, 1
    xvrepl128vei.w VX2, VM0, 2
    xvrepl128vei.w VX3, VM0, 3
    XVFMAX    VM1, VX0, VX1
    XVFMAX    VM2, VX2, VX3
    XVFMAX    VM0, VM1, VM2
#endif
    xvpermi.q VM1, VM0, 0x1
    XVFMAX    VM0, VM0, VM1
    .align 3

.L11:
    andi  I, N, 0x0f
    bge $r0, I, .L13
    .align 3

.L12: /* 0 < N < 16 */
    LD    $f1, X, 0
    addi.d  I, I, -1
    addi.d  X, X, SIZE
    FMAX  $f0, $f0, $f1
    bnez    I, .L12
    .align 3

.L13:
    jirl $r0,  $r1, 0x0
    .align 3

.L20: // INCX!=1
    srai.d I, N, 3
    bge $r0, I, .L23
    .align 3

.L21:
#ifdef DOUBLE
    ld.d t1, X, 0
    add.d X, X, INCX
    ld.d t2, X, 0
    add.d X, X, INCX
    ld.d t3, X, 0
    add.d X, X, INCX
    ld.d t4, X, 0
    add.d X, X, INCX
    xvinsgr2vr.d VX0, t1, 0
    xvinsgr2vr.d VX0, t2, 1
    xvinsgr2vr.d VX0, t3, 2
    xvinsgr2vr.d VX0, t4, 3
    ld.d t1, X, 0
    add.d X, X, INCX
    ld.d t2, X, 0
    add.d X, X, INCX
    ld.d t3, X, 0 * SIZE
    add.d X, X, INCX
    ld.d t4, X, 0 * SIZE
    add.d X, X, INCX
    xvinsgr2vr.d VX1, t1, 0
    xvinsgr2vr.d VX1, t2, 1
    xvinsgr2vr.d VX1, t3, 2
    xvinsgr2vr.d VX1, t4, 3
    xvfmaxa.d VM1, VX0, VX1
    xvfmaxa.d VM0, VM0, VM1
#else
    ld.w t1, X, 0
    add.d X, X, INCX
    ld.w t2, X, 0
    add.d X, X, INCX
    ld.w t3, X, 0
    add.d X, X, INCX
    ld.w t4, X, 0
    add.d X, X, INCX
    xvinsgr2vr.w VM1, t1, 0
    xvinsgr2vr.w VM1, t2, 1
    xvinsgr2vr.w VM1, t3, 2
    xvinsgr2vr.w VM1, t4, 3
    ld.w t1, X, 0
    add.d X, X, INCX
    ld.w t2, X, 0
    add.d X, X, INCX
    ld.w t3, X, 0
    add.d X, X, INCX
    ld.w t4, X, 0
    add.d X, X, INCX
    xvinsgr2vr.w VM1, t1, 4
    xvinsgr2vr.w VM1, t2, 5
    xvinsgr2vr.w VM1, t3, 6
    xvinsgr2vr.w VM1, t4, 7
    xvfmaxa.s VM0, VM0, VM1
#endif
    addi.d I, I, -1
    blt $r0, I, .L21
    .align 3

.L22:
#ifdef DOUBLE
    xvrepl128vei.d VX0, VM0, 0
    xvrepl128vei.d VX1, VM0, 1
    XVFMAX    VM0, VX0, VX1
#else
    xvrepl128vei.w VX0, VM0, 0
    xvrepl128vei.w VX1, VM0, 1
    xvrepl128vei.w VX2, VM0, 2
    xvrepl128vei.w VX3, VM0, 3
    XVFMAX    VM1, VX0, VX1
    XVFMAX    VM2, VX2, VX3
    XVFMAX    VM0, VM1, VM2
#endif
    xvpermi.q VM1, VM0, 1
    XVFMAX    VM0, VM0, VM1
    .align 3

.L23: //INCX!=1 and N<8
    andi I, N, 7
    bge $r0, I, .L999
    .align 3

.L24: /* 0 < N < 8 */
    LD   $f1, X, 0
    addi.d  I, I, -1
    add.d   X, X, INCX
    FMAX  $f0, $f0, $f1
    bnez    I, .L24
    .align 3

.L999:
    jirl $r0, $r1, 0x0

    EPILOGUE
