/* Function log2 vectorized with AVX-512.
   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:
 *
 *    Get short reciprocal approximation Rcp ~ 1/mantissa(x)
 *    R = Rcp*x - 1.0
 *    log2(x) = k - log2(Rcp) + poly_approximation(R)
 *       log2(Rcp) is tabulated
 *
 *
 */

/* Offsets for data table __svml_dlog2_data_internal_avx512
 */
#define Log_tbl                       	0
#define One                           	128
#define C075                          	192
#define poly_coeff9                   	256
#define poly_coeff8                   	320
#define poly_coeff7                   	384
#define poly_coeff6                   	448
#define poly_coeff5                   	512
#define poly_coeff4                   	576
#define poly_coeff3                   	640
#define poly_coeff2                   	704
#define poly_coeff1                   	768

#include <sysdep.h>

        .text
	.section .text.evex512,"ax",@progbits
ENTRY(_ZGVeN8v_log2_skx)
        pushq     %rbp
        cfi_def_cfa_offset(16)
        movq      %rsp, %rbp
        cfi_def_cfa(6, 16)
        cfi_offset(6, -16)
        andq      $-64, %rsp
        subq      $192, %rsp
        vmovaps   %zmm0, %zmm7
        vgetmantpd $8, {sae}, %zmm7, %zmm6
        vmovups   One+__svml_dlog2_data_internal_avx512(%rip), %zmm2
        vmovups   poly_coeff5+__svml_dlog2_data_internal_avx512(%rip), %zmm12
        vmovups   poly_coeff3+__svml_dlog2_data_internal_avx512(%rip), %zmm13

/* Start polynomial evaluation */
        vmovups   poly_coeff9+__svml_dlog2_data_internal_avx512(%rip), %zmm10
        vmovups   poly_coeff8+__svml_dlog2_data_internal_avx512(%rip), %zmm0
        vmovups   poly_coeff7+__svml_dlog2_data_internal_avx512(%rip), %zmm11
        vmovups   poly_coeff6+__svml_dlog2_data_internal_avx512(%rip), %zmm14

/* Prepare exponent correction: DblRcp<0.75? */
        vmovups   C075+__svml_dlog2_data_internal_avx512(%rip), %zmm1

/* Table lookup */
        vmovups   __svml_dlog2_data_internal_avx512(%rip), %zmm4

/* GetExp(x) */
        vgetexppd {sae}, %zmm7, %zmm5

/* DblRcp ~ 1/Mantissa */
        vrcp14pd  %zmm6, %zmm8

/* x<=0? */
        vfpclasspd $94, %zmm7, %k0

/* round DblRcp to 4 fractional bits (RN mode, no Precision exception) */
        vrndscalepd $88, {sae}, %zmm8, %zmm3
        vmovups   poly_coeff4+__svml_dlog2_data_internal_avx512(%rip), %zmm8
        kmovw     %k0, %edx

/* Reduced argument: R = DblRcp*Mantissa - 1 */
        vfmsub213pd {rn-sae}, %zmm2, %zmm3, %zmm6
        vcmppd    $17, {sae}, %zmm1, %zmm3, %k1
        vfmadd231pd {rn-sae}, %zmm6, %zmm12, %zmm8
        vmovups   poly_coeff2+__svml_dlog2_data_internal_avx512(%rip), %zmm12
        vfmadd231pd {rn-sae}, %zmm6, %zmm10, %zmm0
        vfmadd231pd {rn-sae}, %zmm6, %zmm11, %zmm14
        vmovups   poly_coeff1+__svml_dlog2_data_internal_avx512(%rip), %zmm1

/* R^2 */
        vmulpd    {rn-sae}, %zmm6, %zmm6, %zmm15
        vfmadd231pd {rn-sae}, %zmm6, %zmm13, %zmm12

/* Prepare table index */
        vpsrlq    $48, %zmm3, %zmm9

/* add 1 to Expon if DblRcp<0.75 */
        vaddpd    {rn-sae}, %zmm2, %zmm5, %zmm5{%k1}
        vmulpd    {rn-sae}, %zmm15, %zmm15, %zmm13
        vfmadd213pd {rn-sae}, %zmm14, %zmm15, %zmm0
        vfmadd213pd {rn-sae}, %zmm12, %zmm15, %zmm8
        vpermt2pd Log_tbl+64+__svml_dlog2_data_internal_avx512(%rip), %zmm9, %zmm4

/* polynomial */
        vfmadd213pd {rn-sae}, %zmm8, %zmm13, %zmm0
        vfmadd213pd {rn-sae}, %zmm1, %zmm6, %zmm0
        vfmadd213pd {rn-sae}, %zmm4, %zmm0, %zmm6
        vaddpd    {rn-sae}, %zmm6, %zmm5, %zmm0
        testl     %edx, %edx

/* Go to special inputs processing branch */
        jne       L(SPECIAL_VALUES_BRANCH)
                                # LOE rbx r12 r13 r14 r15 edx zmm0 zmm7

/* Restore registers
 * and exit the function
 */

L(EXIT):
        movq      %rbp, %rsp
        popq      %rbp
        cfi_def_cfa(7, 8)
        cfi_restore(6)
        ret
        cfi_def_cfa(6, 16)
        cfi_offset(6, -16)

/* Branch to process
 * special inputs
 */

L(SPECIAL_VALUES_BRANCH):
        vmovups   %zmm7, 64(%rsp)
        vmovups   %zmm0, 128(%rsp)
                                # LOE rbx r12 r13 r14 r15 edx zmm0

        xorl      %eax, %eax
                                # LOE rbx r12 r13 r14 r15 eax edx

        vzeroupper
        movq      %r12, 16(%rsp)
        /*  DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -176; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x50, 0xff, 0xff, 0xff, 0x22
        movl      %eax, %r12d
        movq      %r13, 8(%rsp)
        /*  DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -184; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x48, 0xff, 0xff, 0xff, 0x22
        movl      %edx, %r13d
        movq      %r14, (%rsp)
        /*  DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -192; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x40, 0xff, 0xff, 0xff, 0x22
                                # LOE rbx r15 r12d r13d

/* Range mask
 * bits check
 */

L(RANGEMASK_CHECK):
        btl       %r12d, %r13d

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

/* Special inputs
 * processing loop
 */

L(SPECIAL_VALUES_LOOP):
        incl      %r12d
        cmpl      $8, %r12d

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

        movq      16(%rsp), %r12
        cfi_restore(12)
        movq      8(%rsp), %r13
        cfi_restore(13)
        movq      (%rsp), %r14
        cfi_restore(14)
        vmovups   128(%rsp), %zmm0

/* Go to exit */
        jmp       L(EXIT)
        /*  DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -176; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x50, 0xff, 0xff, 0xff, 0x22
        /*  DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -184; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x48, 0xff, 0xff, 0xff, 0x22
        /*  DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -64; DW_OP_and; DW_OP_const4s: -192; DW_OP_plus)  */
        .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xc0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x40, 0xff, 0xff, 0xff, 0x22
                                # LOE rbx r12 r13 r14 r15 zmm0

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

L(SCALAR_MATH_CALL):
        movl      %r12d, %r14d
        movsd     64(%rsp,%r14,8), %xmm0
        call      log2@PLT
                                # LOE rbx r14 r15 r12d r13d xmm0

        movsd     %xmm0, 128(%rsp,%r14,8)

/* Process special inputs in loop */
        jmp       L(SPECIAL_VALUES_LOOP)
                                # LOE rbx r15 r12d r13d
END(_ZGVeN8v_log2_skx)

        .section .rodata, "a"
        .align 64

#ifdef __svml_dlog2_data_internal_avx512_typedef
typedef unsigned int VUINT32;
typedef struct {
        __declspec(align(64)) VUINT32 Log_tbl[16][2];
        __declspec(align(64)) VUINT32 One[8][2];
        __declspec(align(64)) VUINT32 C075[8][2];
        __declspec(align(64)) VUINT32 poly_coeff9[8][2];
        __declspec(align(64)) VUINT32 poly_coeff8[8][2];
        __declspec(align(64)) VUINT32 poly_coeff7[8][2];
        __declspec(align(64)) VUINT32 poly_coeff6[8][2];
        __declspec(align(64)) VUINT32 poly_coeff5[8][2];
        __declspec(align(64)) VUINT32 poly_coeff4[8][2];
        __declspec(align(64)) VUINT32 poly_coeff3[8][2];
        __declspec(align(64)) VUINT32 poly_coeff2[8][2];
        __declspec(align(64)) VUINT32 poly_coeff1[8][2];
   } __svml_dlog2_data_internal_avx512;
#endif
__svml_dlog2_data_internal_avx512:
        /*== Log_tbl ==*/
        .quad 0x0000000000000000
        .quad 0xbfb663f6fac91316
        .quad 0xbfc5c01a39fbd688
        .quad 0xbfcfbc16b902680a
        .quad 0xbfd49a784bcd1b8b
        .quad 0xbfd91bba891f1709
        .quad 0xbfdd6753e032ea0f
        .quad 0xbfe0c10500d63aa6
        .quad 0x3fda8ff971810a5e
        .quad 0x3fd6cb0f6865c8ea
        .quad 0x3fd32bfee370ee68
        .quad 0x3fcf5fd8a9063e35
        .quad 0x3fc8a8980abfbd32
        .quad 0x3fc22dadc2ab3497
        .quad 0x3fb7d60496cfbb4c
        .quad 0x3fa77394c9d958d5
        /*== One ==*/
        .align 64
        .quad 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000, 0x3ff0000000000000
        /*== C075 0.75 ==*/
        .align 64
        .quad 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000, 0x3fe8000000000000
        /*== poly_coeff9 ==*/
        .align 64
        .quad 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12, 0x3fc4904bda0e1d12
        /*== poly_coeff8 ==*/
        .align 64
        .quad 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce, 0xbfc71fb84deb5cce
        /*== poly_coeff7 ==*/
        .align 64
        .quad 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613, 0x3fca617351818613
        /*== poly_coeff6 ==*/
        .align 64
        .quad 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c, 0xbfcec707e4e3144c
        /*== poly_coeff5 ==*/
        .align 64
        .quad 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a, 0x3fd2776c5114d91a
        /*== poly_coeff4 ==*/
        .align 64
        .quad 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d, 0xbfd71547653d0f8d
        /*== poly_coeff3 ==*/
        .align 64
        .quad 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f, 0x3fdec709dc3a029f
        /*== poly_coeff2 ==*/
        .align 64
        .quad 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4, 0xbfe71547652b82d4
        /*== poly_coeff1 ==*/
        .align 64
        .quad 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe, 0x3ff71547652b82fe
        .align 64
        .type	__svml_dlog2_data_internal_avx512,@object
        .size	__svml_dlog2_data_internal_avx512,.-__svml_dlog2_data_internal_avx512
