Subversion Repositories openrisc_me

/* Assembly functions for the Xtensa version of libgcc1.
   Copyright (C) 2001, 2002, 2003, 2005, 2006, 2007, 2009
   Free Software Foundation, Inc.
   Contributed by Bob Wilson (bwilson@tensilica.com) at Tensilica.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC 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
for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

#include "xtensa-config.h"

/* Define macros for the ABS and ADDX* instructions to handle cases
   where they are not included in the Xtensa processor configuration.  */

        .macro  do_abs dst, src, tmp
#if XCHAL_HAVE_ABS
        abs     \dst, \src
#else
        neg     \tmp, \src
        movgez  \tmp, \src, \src
        mov     \dst, \tmp
#endif
        .endm

        .macro  do_addx2 dst, as, at, tmp
#if XCHAL_HAVE_ADDX
        addx2   \dst, \as, \at
#else
        slli    \tmp, \as, 1
        add     \dst, \tmp, \at
#endif
        .endm

        .macro  do_addx4 dst, as, at, tmp
#if XCHAL_HAVE_ADDX
        addx4   \dst, \as, \at
#else
        slli    \tmp, \as, 2
        add     \dst, \tmp, \at
#endif
        .endm

        .macro  do_addx8 dst, as, at, tmp
#if XCHAL_HAVE_ADDX
        addx8   \dst, \as, \at
#else
        slli    \tmp, \as, 3
        add     \dst, \tmp, \at
#endif
        .endm

/* Define macros for leaf function entry and return, supporting either the
   standard register windowed ABI or the non-windowed call0 ABI.  These
   macros do not allocate any extra stack space, so they only work for
   leaf functions that do not need to spill anything to the stack.  */

        .macro leaf_entry reg, size
#if XCHAL_HAVE_WINDOWED && !__XTENSA_CALL0_ABI__
        entry \reg, \size
#else
        /* do nothing */
#endif
        .endm

        .macro leaf_return
#if XCHAL_HAVE_WINDOWED && !__XTENSA_CALL0_ABI__
        retw
#else
        ret
#endif
        .endm


#ifdef L_mulsi3
        .align  4
        .global __mulsi3
        .type   __mulsi3, @function
__mulsi3:
        leaf_entry sp, 16

#if XCHAL_HAVE_MUL32
        mull    a2, a2, a3

#elif XCHAL_HAVE_MUL16
        or      a4, a2, a3
        srai    a4, a4, 16
        bnez    a4, .LMUL16
        mul16u  a2, a2, a3
        leaf_return
.LMUL16:
        srai    a4, a2, 16
        srai    a5, a3, 16
        mul16u  a7, a4, a3
        mul16u  a6, a5, a2
        mul16u  a4, a2, a3
        add     a7, a7, a6
        slli    a7, a7, 16
        add     a2, a7, a4

#elif XCHAL_HAVE_MAC16
        mul.aa.hl a2, a3
        mula.aa.lh a2, a3
        rsr     a5, ACCLO
        umul.aa.ll a2, a3
        rsr     a4, ACCLO
        slli    a5, a5, 16
        add     a2, a4, a5

#else /* !MUL32 && !MUL16 && !MAC16 */

        /* Multiply one bit at a time, but unroll the loop 4x to better
           exploit the addx instructions and avoid overhead.
           Peel the first iteration to save a cycle on init.  */

        /* Avoid negative numbers.  */
        xor     a5, a2, a3      /* Top bit is 1 if one input is negative.  */
        do_abs  a3, a3, a6
        do_abs  a2, a2, a6

        /* Swap so the second argument is smaller.  */
        sub     a7, a2, a3
        mov     a4, a3
        movgez  a4, a2, a7      /* a4 = max (a2, a3) */
        movltz  a3, a2, a7      /* a3 = min (a2, a3) */

        movi    a2, 0
        extui   a6, a3, 0, 1
        movnez  a2, a4, a6

        do_addx2 a7, a4, a2, a7
        extui   a6, a3, 1, 1
        movnez  a2, a7, a6

        do_addx4 a7, a4, a2, a7
        extui   a6, a3, 2, 1
        movnez  a2, a7, a6

        do_addx8 a7, a4, a2, a7
        extui   a6, a3, 3, 1
        movnez  a2, a7, a6

        bgeui   a3, 16, .Lmult_main_loop
        neg     a3, a2
        movltz  a2, a3, a5
        leaf_return

        .align  4
.Lmult_main_loop:
        srli    a3, a3, 4
        slli    a4, a4, 4

        add     a7, a4, a2
        extui   a6, a3, 0, 1
        movnez  a2, a7, a6

        do_addx2 a7, a4, a2, a7
        extui   a6, a3, 1, 1
        movnez  a2, a7, a6

        do_addx4 a7, a4, a2, a7
        extui   a6, a3, 2, 1
        movnez  a2, a7, a6

        do_addx8 a7, a4, a2, a7
        extui   a6, a3, 3, 1
        movnez  a2, a7, a6

        bgeui   a3, 16, .Lmult_main_loop

        neg     a3, a2
        movltz  a2, a3, a5

#endif /* !MUL32 && !MUL16 && !MAC16 */

        leaf_return
        .size   __mulsi3, . - __mulsi3

#endif /* L_mulsi3 */


#ifdef L_umulsidi3

#if !XCHAL_HAVE_MUL16 && !XCHAL_HAVE_MUL32 && !XCHAL_HAVE_MAC16
#define XCHAL_NO_MUL 1
#endif

        .align  4
        .global __umulsidi3
        .type   __umulsidi3, @function
__umulsidi3:
#if __XTENSA_CALL0_ABI__
        leaf_entry sp, 32
        addi    sp, sp, -32
        s32i    a12, sp, 16
        s32i    a13, sp, 20
        s32i    a14, sp, 24
        s32i    a15, sp, 28
#elif XCHAL_NO_MUL
        /* This is not really a leaf function; allocate enough stack space
           to allow CALL12s to a helper function.  */
        leaf_entry sp, 48
#else
        leaf_entry sp, 16
#endif

#ifdef __XTENSA_EB__
#define wh a2
#define wl a3
#else
#define wh a3
#define wl a2
#endif /* __XTENSA_EB__ */

        /* This code is taken from the mulsf3 routine in ieee754-sf.S.
           See more comments there.  */

#if XCHAL_HAVE_MUL32_HIGH
        mull    a6, a2, a3
        muluh   wh, a2, a3
        mov     wl, a6

#else /* ! MUL32_HIGH */

#if __XTENSA_CALL0_ABI__ && XCHAL_NO_MUL
        /* a0 and a8 will be clobbered by calling the multiply function
           but a8 is not used here and need not be saved.  */
        s32i    a0, sp, 0
#endif

#if XCHAL_HAVE_MUL16 || XCHAL_HAVE_MUL32

#define a2h a4
#define a3h a5

        /* Get the high halves of the inputs into registers.  */
        srli    a2h, a2, 16
        srli    a3h, a3, 16

#define a2l a2
#define a3l a3

#if XCHAL_HAVE_MUL32 && !XCHAL_HAVE_MUL16
        /* Clear the high halves of the inputs.  This does not matter
           for MUL16 because the high bits are ignored.  */
        extui   a2, a2, 0, 16
        extui   a3, a3, 0, 16
#endif
#endif /* MUL16 || MUL32 */


#if XCHAL_HAVE_MUL16

#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
        mul16u  dst, xreg ## xhalf, yreg ## yhalf

#elif XCHAL_HAVE_MUL32

#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
        mull    dst, xreg ## xhalf, yreg ## yhalf

#elif XCHAL_HAVE_MAC16

/* The preprocessor insists on inserting a space when concatenating after
   a period in the definition of do_mul below.  These macros are a workaround
   using underscores instead of periods when doing the concatenation.  */
#define umul_aa_ll umul.aa.ll
#define umul_aa_lh umul.aa.lh
#define umul_aa_hl umul.aa.hl
#define umul_aa_hh umul.aa.hh

#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
        umul_aa_ ## xhalf ## yhalf      xreg, yreg; \
        rsr     dst, ACCLO

#else /* no multiply hardware */

#define set_arg_l(dst, src) \
        extui   dst, src, 0, 16
#define set_arg_h(dst, src) \
        srli    dst, src, 16

#if __XTENSA_CALL0_ABI__
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
        set_arg_ ## xhalf (a13, xreg); \
        set_arg_ ## yhalf (a14, yreg); \
        call0   .Lmul_mulsi3; \
        mov     dst, a12
#else
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
        set_arg_ ## xhalf (a14, xreg); \
        set_arg_ ## yhalf (a15, yreg); \
        call12  .Lmul_mulsi3; \
        mov     dst, a14
#endif /* __XTENSA_CALL0_ABI__ */

#endif /* no multiply hardware */

        /* Add pp1 and pp2 into a6 with carry-out in a9.  */
        do_mul(a6, a2, l, a3, h)        /* pp 1 */
        do_mul(a11, a2, h, a3, l)       /* pp 2 */
        movi    a9, 0
        add     a6, a6, a11
        bgeu    a6, a11, 1f
        addi    a9, a9, 1
1:
        /* Shift the high half of a9/a6 into position in a9.  Note that
           this value can be safely incremented without any carry-outs.  */
        ssai    16
        src     a9, a9, a6

        /* Compute the low word into a6.  */
        do_mul(a11, a2, l, a3, l)       /* pp 0 */
        sll     a6, a6
        add     a6, a6, a11
        bgeu    a6, a11, 1f
        addi    a9, a9, 1
1:
        /* Compute the high word into wh.  */
        do_mul(wh, a2, h, a3, h)        /* pp 3 */
        add     wh, wh, a9
        mov     wl, a6

#endif /* !MUL32_HIGH */

#if __XTENSA_CALL0_ABI__ && XCHAL_NO_MUL
        /* Restore the original return address.  */
        l32i    a0, sp, 0
#endif
#if __XTENSA_CALL0_ABI__
        l32i    a12, sp, 16
        l32i    a13, sp, 20
        l32i    a14, sp, 24
        l32i    a15, sp, 28
        addi    sp, sp, 32
#endif
        leaf_return

#if XCHAL_NO_MUL

        /* For Xtensa processors with no multiply hardware, this simplified
           version of _mulsi3 is used for multiplying 16-bit chunks of
           the floating-point mantissas.  When using CALL0, this function
           uses a custom ABI: the inputs are passed in a13 and a14, the
           result is returned in a12, and a8 and a15 are clobbered.  */
        .align  4
.Lmul_mulsi3:
        leaf_entry sp, 16
        .macro mul_mulsi3_body dst, src1, src2, tmp1, tmp2
        movi    \dst, 0
1:      add     \tmp1, \src2, \dst
        extui   \tmp2, \src1, 0, 1
        movnez  \dst, \tmp1, \tmp2

        do_addx2 \tmp1, \src2, \dst, \tmp1
        extui   \tmp2, \src1, 1, 1
        movnez  \dst, \tmp1, \tmp2

        do_addx4 \tmp1, \src2, \dst, \tmp1
        extui   \tmp2, \src1, 2, 1
        movnez  \dst, \tmp1, \tmp2

        do_addx8 \tmp1, \src2, \dst, \tmp1
        extui   \tmp2, \src1, 3, 1
        movnez  \dst, \tmp1, \tmp2

        srli    \src1, \src1, 4
        slli    \src2, \src2, 4
        bnez    \src1, 1b
        .endm
#if __XTENSA_CALL0_ABI__
        mul_mulsi3_body a12, a13, a14, a15, a8
#else
        /* The result will be written into a2, so save that argument in a4.  */
        mov     a4, a2
        mul_mulsi3_body a2, a4, a3, a5, a6
#endif
        leaf_return
#endif /* XCHAL_NO_MUL */

        .size   __umulsidi3, . - __umulsidi3

#endif /* L_umulsidi3 */


/* Define a macro for the NSAU (unsigned normalize shift amount)
   instruction, which computes the number of leading zero bits,
   to handle cases where it is not included in the Xtensa processor
   configuration.  */

        .macro  do_nsau cnt, val, tmp, a
#if XCHAL_HAVE_NSA
        nsau    \cnt, \val
#else
        mov     \a, \val
        movi    \cnt, 0
        extui   \tmp, \a, 16, 16
        bnez    \tmp, 0f
        movi    \cnt, 16
        slli    \a, \a, 16
0:
        extui   \tmp, \a, 24, 8
        bnez    \tmp, 1f
        addi    \cnt, \cnt, 8
        slli    \a, \a, 8
1:
        movi    \tmp, __nsau_data
        extui   \a, \a, 24, 8
        add     \tmp, \tmp, \a
        l8ui    \tmp, \tmp, 0
        add     \cnt, \cnt, \tmp
#endif /* !XCHAL_HAVE_NSA */
        .endm

#ifdef L_clz
        .section .rodata
        .align  4
        .global __nsau_data
        .type   __nsau_data, @object
__nsau_data:
#if !XCHAL_HAVE_NSA
        .byte   8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4
        .byte   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
        .byte   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
        .byte   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
#endif /* !XCHAL_HAVE_NSA */
        .size   __nsau_data, . - __nsau_data
        .hidden __nsau_data
#endif /* L_clz */


#ifdef L_clzsi2
        .align  4
        .global __clzsi2
        .type   __clzsi2, @function
__clzsi2:
        leaf_entry sp, 16
        do_nsau a2, a2, a3, a4
        leaf_return
        .size   __clzsi2, . - __clzsi2

#endif /* L_clzsi2 */


#ifdef L_ctzsi2
        .align  4
        .global __ctzsi2
        .type   __ctzsi2, @function
__ctzsi2:
        leaf_entry sp, 16
        neg     a3, a2
        and     a3, a3, a2
        do_nsau a2, a3, a4, a5
        neg     a2, a2
        addi    a2, a2, 31
        leaf_return
        .size   __ctzsi2, . - __ctzsi2

#endif /* L_ctzsi2 */


#ifdef L_ffssi2
        .align  4
        .global __ffssi2
        .type   __ffssi2, @function
__ffssi2:
        leaf_entry sp, 16
        neg     a3, a2
        and     a3, a3, a2
        do_nsau a2, a3, a4, a5
        neg     a2, a2
        addi    a2, a2, 32
        leaf_return
        .size   __ffssi2, . - __ffssi2

#endif /* L_ffssi2 */


#ifdef L_udivsi3
        .align  4
        .global __udivsi3
        .type   __udivsi3, @function
__udivsi3:
        leaf_entry sp, 16
#if XCHAL_HAVE_DIV32
        quou    a2, a2, a3
#else
        bltui   a3, 2, .Lle_one /* check if the divisor <= 1 */

        mov     a6, a2          /* keep dividend in a6 */
        do_nsau a5, a6, a2, a7  /* dividend_shift = nsau (dividend) */
        do_nsau a4, a3, a2, a7  /* divisor_shift = nsau (divisor) */
        bgeu    a5, a4, .Lspecial

        sub     a4, a4, a5      /* count = divisor_shift - dividend_shift */
        ssl     a4
        sll     a3, a3          /* divisor <<= count */
        movi    a2, 0           /* quotient = 0 */

        /* test-subtract-and-shift loop; one quotient bit on each iteration */
#if XCHAL_HAVE_LOOPS
        loopnez a4, .Lloopend
#endif /* XCHAL_HAVE_LOOPS */
.Lloop:
        bltu    a6, a3, .Lzerobit
        sub     a6, a6, a3
        addi    a2, a2, 1
.Lzerobit:
        slli    a2, a2, 1
        srli    a3, a3, 1
#if !XCHAL_HAVE_LOOPS
        addi    a4, a4, -1
        bnez    a4, .Lloop
#endif /* !XCHAL_HAVE_LOOPS */
.Lloopend:

        bltu    a6, a3, .Lreturn
        addi    a2, a2, 1       /* increment quotient if dividend >= divisor */
.Lreturn:
        leaf_return

.Lle_one:
        beqz    a3, .Lerror     /* if divisor == 1, return the dividend */
        leaf_return

.Lspecial:
        /* return dividend >= divisor */
        bltu    a6, a3, .Lreturn0
        movi    a2, 1
        leaf_return

.Lerror:
        /* Divide by zero: Use an illegal instruction to force an exception.
           The subsequent "DIV0" string can be recognized by the exception
           handler to identify the real cause of the exception.  */
        ill
        .ascii  "DIV0"

.Lreturn0:
        movi    a2, 0
#endif /* XCHAL_HAVE_DIV32 */
        leaf_return
        .size   __udivsi3, . - __udivsi3

#endif /* L_udivsi3 */


#ifdef L_divsi3
        .align  4
        .global __divsi3
        .type   __divsi3, @function
__divsi3:
        leaf_entry sp, 16
#if XCHAL_HAVE_DIV32
        quos    a2, a2, a3
#else
        xor     a7, a2, a3      /* sign = dividend ^ divisor */
        do_abs  a6, a2, a4      /* udividend = abs (dividend) */
        do_abs  a3, a3, a4      /* udivisor = abs (divisor) */
        bltui   a3, 2, .Lle_one /* check if udivisor <= 1 */
        do_nsau a5, a6, a2, a8  /* udividend_shift = nsau (udividend) */
        do_nsau a4, a3, a2, a8  /* udivisor_shift = nsau (udivisor) */
        bgeu    a5, a4, .Lspecial

        sub     a4, a4, a5      /* count = udivisor_shift - udividend_shift */
        ssl     a4
        sll     a3, a3          /* udivisor <<= count */
        movi    a2, 0           /* quotient = 0 */

        /* test-subtract-and-shift loop; one quotient bit on each iteration */
#if XCHAL_HAVE_LOOPS
        loopnez a4, .Lloopend
#endif /* XCHAL_HAVE_LOOPS */
.Lloop:
        bltu    a6, a3, .Lzerobit
        sub     a6, a6, a3
        addi    a2, a2, 1
.Lzerobit:
        slli    a2, a2, 1
        srli    a3, a3, 1
#if !XCHAL_HAVE_LOOPS
        addi    a4, a4, -1
        bnez    a4, .Lloop
#endif /* !XCHAL_HAVE_LOOPS */
.Lloopend:

        bltu    a6, a3, .Lreturn
        addi    a2, a2, 1       /* increment if udividend >= udivisor */
.Lreturn:
        neg     a5, a2
        movltz  a2, a5, a7      /* return (sign < 0) ? -quotient : quotient */
        leaf_return

.Lle_one:
        beqz    a3, .Lerror
        neg     a2, a6          /* if udivisor == 1, then return... */
        movgez  a2, a6, a7      /* (sign < 0) ? -udividend : udividend */
        leaf_return

.Lspecial:
        bltu    a6, a3, .Lreturn0 /* if dividend < divisor, return 0 */
        movi    a2, 1
        movi    a4, -1
        movltz  a2, a4, a7      /* else return (sign < 0) ? -1 : 1 */
        leaf_return

.Lerror:
        /* Divide by zero: Use an illegal instruction to force an exception.
           The subsequent "DIV0" string can be recognized by the exception
           handler to identify the real cause of the exception.  */
        ill
        .ascii  "DIV0"

.Lreturn0:
        movi    a2, 0
#endif /* XCHAL_HAVE_DIV32 */
        leaf_return
        .size   __divsi3, . - __divsi3

#endif /* L_divsi3 */


#ifdef L_umodsi3
        .align  4
        .global __umodsi3
        .type   __umodsi3, @function
__umodsi3:
        leaf_entry sp, 16
#if XCHAL_HAVE_DIV32
        remu    a2, a2, a3
#else
        bltui   a3, 2, .Lle_one /* check if the divisor is <= 1 */

        do_nsau a5, a2, a6, a7  /* dividend_shift = nsau (dividend) */
        do_nsau a4, a3, a6, a7  /* divisor_shift = nsau (divisor) */
        bgeu    a5, a4, .Lspecial

        sub     a4, a4, a5      /* count = divisor_shift - dividend_shift */
        ssl     a4
        sll     a3, a3          /* divisor <<= count */

        /* test-subtract-and-shift loop */
#if XCHAL_HAVE_LOOPS
        loopnez a4, .Lloopend
#endif /* XCHAL_HAVE_LOOPS */
.Lloop:
        bltu    a2, a3, .Lzerobit
        sub     a2, a2, a3
.Lzerobit:
        srli    a3, a3, 1
#if !XCHAL_HAVE_LOOPS
        addi    a4, a4, -1
        bnez    a4, .Lloop
#endif /* !XCHAL_HAVE_LOOPS */
.Lloopend:

.Lspecial:
        bltu    a2, a3, .Lreturn
        sub     a2, a2, a3      /* subtract once more if dividend >= divisor */
.Lreturn:
        leaf_return

.Lle_one:
        bnez    a3, .Lreturn0

        /* Divide by zero: Use an illegal instruction to force an exception.
           The subsequent "DIV0" string can be recognized by the exception
           handler to identify the real cause of the exception.  */
        ill
        .ascii  "DIV0"

.Lreturn0:
        movi    a2, 0
#endif /* XCHAL_HAVE_DIV32 */
        leaf_return
        .size   __umodsi3, . - __umodsi3

#endif /* L_umodsi3 */


#ifdef L_modsi3
        .align  4
        .global __modsi3
        .type   __modsi3, @function
__modsi3:
        leaf_entry sp, 16
#if XCHAL_HAVE_DIV32
        rems    a2, a2, a3
#else
        mov     a7, a2          /* save original (signed) dividend */
        do_abs  a2, a2, a4      /* udividend = abs (dividend) */
        do_abs  a3, a3, a4      /* udivisor = abs (divisor) */
        bltui   a3, 2, .Lle_one /* check if udivisor <= 1 */
        do_nsau a5, a2, a6, a8  /* udividend_shift = nsau (udividend) */
        do_nsau a4, a3, a6, a8  /* udivisor_shift = nsau (udivisor) */
        bgeu    a5, a4, .Lspecial

        sub     a4, a4, a5      /* count = udivisor_shift - udividend_shift */
        ssl     a4
        sll     a3, a3          /* udivisor <<= count */

        /* test-subtract-and-shift loop */
#if XCHAL_HAVE_LOOPS
        loopnez a4, .Lloopend
#endif /* XCHAL_HAVE_LOOPS */
.Lloop:
        bltu    a2, a3, .Lzerobit
        sub     a2, a2, a3
.Lzerobit:
        srli    a3, a3, 1
#if !XCHAL_HAVE_LOOPS
        addi    a4, a4, -1
        bnez    a4, .Lloop
#endif /* !XCHAL_HAVE_LOOPS */
.Lloopend:

.Lspecial:
        bltu    a2, a3, .Lreturn
        sub     a2, a2, a3      /* subtract again if udividend >= udivisor */
.Lreturn:
        bgez    a7, .Lpositive
        neg     a2, a2          /* if (dividend < 0), return -udividend */
.Lpositive:
        leaf_return

.Lle_one:
        bnez    a3, .Lreturn0

        /* Divide by zero: Use an illegal instruction to force an exception.
           The subsequent "DIV0" string can be recognized by the exception
           handler to identify the real cause of the exception.  */
        ill
        .ascii  "DIV0"

.Lreturn0:
        movi    a2, 0
#endif /* XCHAL_HAVE_DIV32 */
        leaf_return
        .size   __modsi3, . - __modsi3

#endif /* L_modsi3 */


#ifdef __XTENSA_EB__
#define uh a2
#define ul a3
#else
#define uh a3
#define ul a2
#endif /* __XTENSA_EB__ */


#ifdef L_ashldi3
        .align  4
        .global __ashldi3
        .type   __ashldi3, @function
__ashldi3:
        leaf_entry sp, 16
        ssl     a4
        bgei    a4, 32, .Llow_only
        src     uh, uh, ul
        sll     ul, ul
        leaf_return

.Llow_only:
        sll     uh, ul
        movi    ul, 0
        leaf_return
        .size   __ashldi3, . - __ashldi3

#endif /* L_ashldi3 */


#ifdef L_ashrdi3
        .align  4
        .global __ashrdi3
        .type   __ashrdi3, @function
__ashrdi3:
        leaf_entry sp, 16
        ssr     a4
        bgei    a4, 32, .Lhigh_only
        src     ul, uh, ul
        sra     uh, uh
        leaf_return

.Lhigh_only:
        sra     ul, uh
        srai    uh, uh, 31
        leaf_return
        .size   __ashrdi3, . - __ashrdi3

#endif /* L_ashrdi3 */


#ifdef L_lshrdi3
        .align  4
        .global __lshrdi3
        .type   __lshrdi3, @function
__lshrdi3:
        leaf_entry sp, 16
        ssr     a4
        bgei    a4, 32, .Lhigh_only1
        src     ul, uh, ul
        srl     uh, uh
        leaf_return

.Lhigh_only1:
        srl     ul, uh
        movi    uh, 0
        leaf_return
        .size   __lshrdi3, . - __lshrdi3

#endif /* L_lshrdi3 */


#include "ieee754-df.S"
#include "ieee754-sf.S"