/* Function exp10f vectorized with SSE4.
   Copyright (C) 2021-2022 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C 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 C 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 C Library; if not, see
   https://www.gnu.org/licenses/.  */

/*
 * ALGORITHM DESCRIPTION:
 *
 *   exp10(x)  = 2^x/log10(2) = 2^n * (1 + T[j]) * (1 + P(y))
 *   where
 *        x = m*log10(2)/K + y,  y in [-log10(2)/K..log10(2)/K]
 *        m = n*K + j,           m,n,j - signed integer, j in [-K/2..K/2]
 *
 *        values of 2^j/K are tabulated
 *
 *        P(y) is a minimax polynomial approximation of exp10(x)-1
 *        on small interval [-log10(2)/K..log10(2)/K]
 *
 *  Special cases:
 *
 *   exp10(NaN)  = NaN
 *   exp10(+INF) = +INF
 *   exp10(-INF) = 0
 *   exp10(x)    = 1 for subnormals
 *   For IEEE float
 *     if x >  38.5318412780761720 then exp10f(x) overflow
 *     if x < -45.4555282592773440 then exp10f(x) underflow
 *
 */

/* Offsets for data table __svml_sexp10_data_internal
 */
#define _sT                           	0
#define _sLg2_10                      	128
#define _sShifter                     	144
#define _sInvLg2_10hi                 	160
#define _sInvLg2_10lo                 	176
#define _sPC0                         	192
#define _sPC1                         	208
#define _sPC2                         	224
#define _iIndexMask                   	240
#define _iAbsMask                     	256
#define _iDomainRange                 	272

#include <sysdep.h>

        .text
	.section .text.sse4,"ax",@progbits
ENTRY(_ZGVbN4v_exp10f_sse4)
        subq      $72, %rsp
        cfi_def_cfa_offset(80)
        movaps    %xmm0, %xmm4

/*  Load arument  */
        movups    _sLg2_10+__svml_sexp10_data_internal(%rip), %xmm2
        lea       __svml_sexp10_data_internal(%rip), %r8
        mulps     %xmm4, %xmm2
        movups    _sShifter+__svml_sexp10_data_internal(%rip), %xmm5

/*  R  */
        movups    _sInvLg2_10hi+__svml_sexp10_data_internal(%rip), %xmm14
        addps     %xmm5, %xmm2
        movaps    %xmm2, %xmm1
        movups    _sInvLg2_10lo+__svml_sexp10_data_internal(%rip), %xmm15
        subps     %xmm5, %xmm1
        mulps     %xmm1, %xmm14
        movaps    %xmm4, %xmm5
        mulps     %xmm1, %xmm15
        subps     %xmm14, %xmm5

/*
 *  Polynomial
 * exp10 = 2^N*(Tj+Tj*poly)
 * poly(sN) = {1+later} a0+a1*sR
 */
        movups    _sPC2+__svml_sexp10_data_internal(%rip), %xmm1
        subps     %xmm15, %xmm5
        mulps     %xmm5, %xmm1
        movdqu    _iIndexMask+__svml_sexp10_data_internal(%rip), %xmm3

/*  Index and lookup  */
        movdqa    %xmm3, %xmm10

/* remove index bits */
        pandn     %xmm2, %xmm3
        pand      %xmm2, %xmm10

/*  2^N  */
        pslld     $18, %xmm3

/* iIndex *= sizeof(S); */
        pslld     $2, %xmm10
        addps     _sPC1+__svml_sexp10_data_internal(%rip), %xmm1
        movd      %xmm10, %edx
        pshufd    $1, %xmm10, %xmm7
        pshufd    $2, %xmm10, %xmm9
        pshufd    $3, %xmm10, %xmm11
        movd      %xmm7, %ecx
        movd      %xmm9, %esi
        movd      %xmm11, %edi

/* Check for overflow\underflow  */
        movdqu    _iAbsMask+__svml_sexp10_data_internal(%rip), %xmm6
        pand      %xmm4, %xmm6
        mulps     %xmm1, %xmm5
        movslq    %edx, %rdx
        addps     _sPC0+__svml_sexp10_data_internal(%rip), %xmm5
        movslq    %ecx, %rcx
        movslq    %esi, %rsi
        movslq    %edi, %rdi
        movd      (%r8,%rdx), %xmm0
        movd      (%r8,%rcx), %xmm8
        movd      (%r8,%rsi), %xmm13
        movd      (%r8,%rdi), %xmm12
        punpckldq %xmm8, %xmm0
        punpckldq %xmm12, %xmm13
        punpcklqdq %xmm13, %xmm0

/* Tj_l+Tj_h*poly */
        mulps     %xmm0, %xmm5
        pcmpgtd   _iDomainRange+__svml_sexp10_data_internal(%rip), %xmm6
        addps     %xmm5, %xmm0
        movmskps  %xmm6, %eax

/* quick mul 2^N */
        paddd     %xmm3, %xmm0

/*  Finish   */
        testl     %eax, %eax

/* Go to special inputs processing branch */
        jne       L(SPECIAL_VALUES_BRANCH)
                                # LOE rbx rbp r12 r13 r14 r15 eax xmm0 xmm4

/* Restore registers
 * and exit the function
 */

L(EXIT):
        addq      $72, %rsp
        cfi_def_cfa_offset(8)
        ret
        cfi_def_cfa_offset(80)

/* Branch to process
 * special inputs
 */

L(SPECIAL_VALUES_BRANCH):
        movups    %xmm4, 32(%rsp)
        movups    %xmm0, 48(%rsp)
                                # LOE rbx rbp r12 r13 r14 r15 eax

        xorl      %edx, %edx
        movq      %r12, 16(%rsp)
        cfi_offset(12, -64)
        movl      %edx, %r12d
        movq      %r13, 8(%rsp)
        cfi_offset(13, -72)
        movl      %eax, %r13d
        movq      %r14, (%rsp)
        cfi_offset(14, -80)
                                # LOE rbx rbp r15 r12d r13d

/* Range mask
 * bits check
 */

L(RANGEMASK_CHECK):
        btl       %r12d, %r13d

/* Call scalar math function */
        jc        L(SCALAR_MATH_CALL)
                                # LOE rbx rbp r15 r12d r13d

/* Special inputs
 * processing loop
 */

L(SPECIAL_VALUES_LOOP):
        incl      %r12d
        cmpl      $4, %r12d

/* Check bits in range mask */
        jl        L(RANGEMASK_CHECK)
                                # LOE rbx rbp r15 r12d r13d

        movq      16(%rsp), %r12
        cfi_restore(12)
        movq      8(%rsp), %r13
        cfi_restore(13)
        movq      (%rsp), %r14
        cfi_restore(14)
        movups    48(%rsp), %xmm0

/* Go to exit */
        jmp       L(EXIT)
        cfi_offset(12, -64)
        cfi_offset(13, -72)
        cfi_offset(14, -80)
                                # LOE rbx rbp r12 r13 r14 r15 xmm0

/* Scalar math fucntion call
 * to process special input
 */

L(SCALAR_MATH_CALL):
        movl      %r12d, %r14d
        movss     32(%rsp,%r14,4), %xmm0
        call      exp10f@PLT
                                # LOE rbx rbp r14 r15 r12d r13d xmm0

        movss     %xmm0, 48(%rsp,%r14,4)

/* Process special inputs in loop */
        jmp       L(SPECIAL_VALUES_LOOP)
                                # LOE rbx rbp r15 r12d r13d
END(_ZGVbN4v_exp10f_sse4)

        .section .rodata, "a"
        .align 16

#ifdef __svml_sexp10_data_internal_typedef
typedef unsigned int VUINT32;
typedef struct
{
        __declspec(align(16)) VUINT32 _sT[(1<<5)][1];
        __declspec(align(16)) VUINT32 _sLg2_10[4][1];
        __declspec(align(16)) VUINT32 _sShifter[4][1];
        __declspec(align(16)) VUINT32 _sInvLg2_10hi[4][1];
        __declspec(align(16)) VUINT32 _sInvLg2_10lo[4][1];
        __declspec(align(16)) VUINT32 _sPC0[4][1];
        __declspec(align(16)) VUINT32 _sPC1[4][1];
        __declspec(align(16)) VUINT32 _sPC2[4][1];
        __declspec(align(16)) VUINT32 _iIndexMask[4][1];
        __declspec(align(16)) VUINT32 _iAbsMask[4][1];
        __declspec(align(16)) VUINT32 _iDomainRange[4][1];
} __svml_sexp10_data_internal;
#endif
__svml_sexp10_data_internal:
        /*== _sT ==*/
        .long 0x3f800000  // 2^( 0 /32 )
        .long 0x3f82cd87  // 2^( 1 /32 )
        .long 0x3f85aac3  // 2^( 2 /32 )
        .long 0x3f88980f  // 2^( 3 /32 )
        .long 0x3f8b95c2  // 2^( 4 /32 )
        .long 0x3f8ea43a  // 2^( 5 /32 )
        .long 0x3f91c3d3  // 2^( 6 /32 )
        .long 0x3f94f4f0  // 2^( 7 /32 )
        .long 0x3f9837f0  // 2^( 8 /32 )
        .long 0x3f9b8d3a  // 2^( 9 /32 )
        .long 0x3f9ef532  // 2^( 10/32 )
        .long 0x3fa27043  // 2^( 11/32 )
        .long 0x3fa5fed7  // 2^( 12/32 )
        .long 0x3fa9a15b  // 2^( 13/32 )
        .long 0x3fad583f  // 2^( 14/32 )
        .long 0x3fb123f6  // 2^( 15/32 )
        .long 0x3fb504f3  // 2^( 16/32 )
        .long 0x3fb8fbaf  // 2^( 17/32 )
        .long 0x3fbd08a4  // 2^( 18/32 )
        .long 0x3fc12c4d  // 2^( 19/32 )
        .long 0x3fc5672a  // 2^( 20/32 )
        .long 0x3fc9b9be  // 2^( 21/32 )
        .long 0x3fce248c  // 2^( 22/32 )
        .long 0x3fd2a81e  // 2^( 23/32 )
        .long 0x3fd744fd  // 2^( 24/32 )
        .long 0x3fdbfbb8  // 2^( 25/32 )
        .long 0x3fe0ccdf  // 2^( 26/32 )
        .long 0x3fe5b907  // 2^( 27/32 )
        .long 0x3feac0c7  // 2^( 28/32 )
        .long 0x3fefe4ba  // 2^( 29/32 )
        .long 0x3ff5257d  // 2^( 30/32 )
        .long 0x3ffa83b3  // 2^( 31/32 )
        .align 16
        .long 0x42d49a78, 0x42d49a78, 0x42d49a78, 0x42d49a78  /* _sLg2_10*2^K   */
        .align 16
        .long 0x4b400000, 0x4b400000, 0x4b400000, 0x4b400000  /* _sShifter) */
        .align 16
        .long 0x3c1a2000, 0x3c1a2000, 0x3c1a2000, 0x3c1a2000  /* _sInvLg2_10hi/2^K hi (24-K-7) bits*/
        .align 16
        .long 0x341a84fc, 0x341a84fc, 0x341a84fc, 0x341a84fc  /* _sInvLg2_10lo/2^K  lo bits */
        // otherwise exp10(0) won't produce exact 1.0
        .align 16
        .long 0x2fecc868, 0x2fecc868, 0x2fecc868, 0x2fecc868  /* _sPC0 */
        .align 16
        .long 0x40135e1b, 0x40135e1b, 0x40135e1b, 0x40135e1b  /* _sPC1 */
        .align 16
        .long 0x4029a8d2, 0x4029a8d2, 0x4029a8d2, 0x4029a8d2  /* _sPC2 */
        .align 16
        .long 0x0000001f, 0x0000001f, 0x0000001f, 0x0000001f  /* _iIndexMask =(2^K-1)*/
        //common
        .align 16
        .long 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff   /* _iAbsMask */
        .align 16
        .long 0x4217b818, 0x4217b818, 0x4217b818, 0x4217b818   /* _iDomainRange=-log10(max_denormal=0x007fffff) RZ */
        .align 16
        .type	__svml_sexp10_data_internal,@object
        .size	__svml_sexp10_data_internal,.-__svml_sexp10_data_internal
