Subversion Repositories openrisc

/* ieee754-sf.S single-precision floating point support for ARM

   Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009  Free Software Foundation, Inc.
   Contributed by Nicolas Pitre (nico@cam.org)

   This file 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.

   This file 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/>.  */

/*
 * Notes:
 *
 * The goal of this code is to be as fast as possible.  This is
 * not meant to be easy to understand for the casual reader.
 *
 * Only the default rounding mode is intended for best performances.
 * Exceptions aren't supported yet, but that can be added quite easily
 * if necessary without impacting performances.
 */

#ifdef L_arm_negsf2
        
ARM_FUNC_START negsf2
ARM_FUNC_ALIAS aeabi_fneg negsf2

        eor     r0, r0, #0x80000000     @ flip sign bit
        RET

        FUNC_END aeabi_fneg
        FUNC_END negsf2

#endif

#ifdef L_arm_addsubsf3

ARM_FUNC_START aeabi_frsub

        eor     r0, r0, #0x80000000     @ flip sign bit of first arg
        b       1f

ARM_FUNC_START subsf3
ARM_FUNC_ALIAS aeabi_fsub subsf3

        eor     r1, r1, #0x80000000     @ flip sign bit of second arg
#if defined(__INTERWORKING_STUBS__)
        b       1f                      @ Skip Thumb-code prologue
#endif

ARM_FUNC_START addsf3
ARM_FUNC_ALIAS aeabi_fadd addsf3

1:      @ Look for zeroes, equal values, INF, or NAN.
        movs    r2, r0, lsl #1
        do_it   ne, ttt
        COND(mov,s,ne)  r3, r1, lsl #1
        teqne   r2, r3
        COND(mvn,s,ne)  ip, r2, asr #24
        COND(mvn,s,ne)  ip, r3, asr #24
        beq     LSYM(Lad_s)

        @ Compute exponent difference.  Make largest exponent in r2,
        @ corresponding arg in r0, and positive exponent difference in r3.
        mov     r2, r2, lsr #24
        rsbs    r3, r2, r3, lsr #24
        do_it   gt, ttt
        addgt   r2, r2, r3
        eorgt   r1, r0, r1
        eorgt   r0, r1, r0
        eorgt   r1, r0, r1
        do_it   lt
        rsblt   r3, r3, #0

        @ If exponent difference is too large, return largest argument
        @ already in r0.  We need up to 25 bit to handle proper rounding
        @ of 0x1p25 - 1.1.
        cmp     r3, #25
        do_it   hi
        RETc(hi)

        @ Convert mantissa to signed integer.
        tst     r0, #0x80000000
        orr     r0, r0, #0x00800000
        bic     r0, r0, #0xff000000
        do_it   ne
        rsbne   r0, r0, #0
        tst     r1, #0x80000000
        orr     r1, r1, #0x00800000
        bic     r1, r1, #0xff000000
        do_it   ne
        rsbne   r1, r1, #0

        @ If exponent == difference, one or both args were denormalized.
        @ Since this is not common case, rescale them off line.
        teq     r2, r3
        beq     LSYM(Lad_d)
LSYM(Lad_x):

        @ Compensate for the exponent overlapping the mantissa MSB added later
        sub     r2, r2, #1

        @ Shift and add second arg to first arg in r0.
        @ Keep leftover bits into r1.
        shiftop adds r0 r0 r1 asr r3 ip
        rsb     r3, r3, #32
        shift1  lsl, r1, r1, r3

        @ Keep absolute value in r0-r1, sign in r3 (the n bit was set above)
        and     r3, r0, #0x80000000
        bpl     LSYM(Lad_p)
#if defined(__thumb2__)
        negs    r1, r1
        sbc     r0, r0, r0, lsl #1
#else
        rsbs    r1, r1, #0
        rsc     r0, r0, #0
#endif

        @ Determine how to normalize the result.
LSYM(Lad_p):
        cmp     r0, #0x00800000
        bcc     LSYM(Lad_a)
        cmp     r0, #0x01000000
        bcc     LSYM(Lad_e)

        @ Result needs to be shifted right.
        movs    r0, r0, lsr #1
        mov     r1, r1, rrx
        add     r2, r2, #1

        @ Make sure we did not bust our exponent.
        cmp     r2, #254
        bhs     LSYM(Lad_o)

        @ Our result is now properly aligned into r0, remaining bits in r1.
        @ Pack final result together.
        @ Round with MSB of r1. If halfway between two numbers, round towards
        @ LSB of r0 = 0. 
LSYM(Lad_e):
        cmp     r1, #0x80000000
        adc     r0, r0, r2, lsl #23
        do_it   eq
        biceq   r0, r0, #1
        orr     r0, r0, r3
        RET

        @ Result must be shifted left and exponent adjusted.
LSYM(Lad_a):
        movs    r1, r1, lsl #1
        adc     r0, r0, r0
        tst     r0, #0x00800000
        sub     r2, r2, #1
        bne     LSYM(Lad_e)
        
        @ No rounding necessary since r1 will always be 0 at this point.
LSYM(Lad_l):

#if __ARM_ARCH__ < 5

        movs    ip, r0, lsr #12
        moveq   r0, r0, lsl #12
        subeq   r2, r2, #12
        tst     r0, #0x00ff0000
        moveq   r0, r0, lsl #8
        subeq   r2, r2, #8
        tst     r0, #0x00f00000
        moveq   r0, r0, lsl #4
        subeq   r2, r2, #4
        tst     r0, #0x00c00000
        moveq   r0, r0, lsl #2
        subeq   r2, r2, #2
        cmp     r0, #0x00800000
        movcc   r0, r0, lsl #1
        sbcs    r2, r2, #0

#else

        clz     ip, r0
        sub     ip, ip, #8
        subs    r2, r2, ip
        shift1  lsl, r0, r0, ip

#endif

        @ Final result with sign
        @ If exponent negative, denormalize result.
        do_it   ge, et
        addge   r0, r0, r2, lsl #23
        rsblt   r2, r2, #0
        orrge   r0, r0, r3
#if defined(__thumb2__)
        do_it   lt, t
        lsrlt   r0, r0, r2
        orrlt   r0, r3, r0
#else
        orrlt   r0, r3, r0, lsr r2
#endif
        RET

        @ Fixup and adjust bit position for denormalized arguments.
        @ Note that r2 must not remain equal to 0.
LSYM(Lad_d):
        teq     r2, #0
        eor     r1, r1, #0x00800000
        do_it   eq, te
        eoreq   r0, r0, #0x00800000
        addeq   r2, r2, #1
        subne   r3, r3, #1
        b       LSYM(Lad_x)

LSYM(Lad_s):
        mov     r3, r1, lsl #1

        mvns    ip, r2, asr #24
        do_it   ne
        COND(mvn,s,ne)  ip, r3, asr #24
        beq     LSYM(Lad_i)

        teq     r2, r3
        beq     1f

        @ Result is x + 0.0 = x or 0.0 + y = y.
        teq     r2, #0
        do_it   eq
        moveq   r0, r1
        RET

1:      teq     r0, r1

        @ Result is x - x = 0.
        do_it   ne, t
        movne   r0, #0
        RETc(ne)

        @ Result is x + x = 2x.
        tst     r2, #0xff000000
        bne     2f
        movs    r0, r0, lsl #1
        do_it   cs
        orrcs   r0, r0, #0x80000000
        RET
2:      adds    r2, r2, #(2 << 24)
        do_it   cc, t
        addcc   r0, r0, #(1 << 23)
        RETc(cc)
        and     r3, r0, #0x80000000

        @ Overflow: return INF.
LSYM(Lad_o):
        orr     r0, r3, #0x7f000000
        orr     r0, r0, #0x00800000
        RET

        @ At least one of r0/r1 is INF/NAN.
        @   if r0 != INF/NAN: return r1 (which is INF/NAN)
        @   if r1 != INF/NAN: return r0 (which is INF/NAN)
        @   if r0 or r1 is NAN: return NAN
        @   if opposite sign: return NAN
        @   otherwise return r0 (which is INF or -INF)
LSYM(Lad_i):
        mvns    r2, r2, asr #24
        do_it   ne, et
        movne   r0, r1
        COND(mvn,s,eq)  r3, r3, asr #24
        movne   r1, r0
        movs    r2, r0, lsl #9
        do_it   eq, te
        COND(mov,s,eq)  r3, r1, lsl #9
        teqeq   r0, r1
        orrne   r0, r0, #0x00400000     @ quiet NAN
        RET

        FUNC_END aeabi_frsub
        FUNC_END aeabi_fadd
        FUNC_END addsf3
        FUNC_END aeabi_fsub
        FUNC_END subsf3

ARM_FUNC_START floatunsisf
ARM_FUNC_ALIAS aeabi_ui2f floatunsisf
                
        mov     r3, #0
        b       1f

ARM_FUNC_START floatsisf
ARM_FUNC_ALIAS aeabi_i2f floatsisf
        
        ands    r3, r0, #0x80000000
        do_it   mi
        rsbmi   r0, r0, #0

1:      movs    ip, r0
        do_it   eq
        RETc(eq)

        @ Add initial exponent to sign
        orr     r3, r3, #((127 + 23) << 23)

        .ifnc   ah, r0
        mov     ah, r0
        .endif
        mov     al, #0
        b       2f

        FUNC_END aeabi_i2f
        FUNC_END floatsisf
        FUNC_END aeabi_ui2f
        FUNC_END floatunsisf

ARM_FUNC_START floatundisf
ARM_FUNC_ALIAS aeabi_ul2f floatundisf

        orrs    r2, r0, r1
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        do_it   eq, t
        mvfeqs  f0, #0.0
#else
        do_it   eq
#endif
        RETc(eq)

        mov     r3, #0
        b       1f

ARM_FUNC_START floatdisf
ARM_FUNC_ALIAS aeabi_l2f floatdisf

        orrs    r2, r0, r1
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        do_it   eq, t
        mvfeqs  f0, #0.0
#else
        do_it   eq
#endif
        RETc(eq)

        ands    r3, ah, #0x80000000     @ sign bit in r3
        bpl     1f
#if defined(__thumb2__)
        negs    al, al
        sbc     ah, ah, ah, lsl #1
#else
        rsbs    al, al, #0
        rsc     ah, ah, #0
#endif
1:
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        @ For hard FPA code we want to return via the tail below so that
        @ we can return the result in f0 as well as in r0 for backwards
        @ compatibility.
        str     lr, [sp, #-8]!
        adr     lr, LSYM(f0_ret)
#endif

        movs    ip, ah
        do_it   eq, tt
        moveq   ip, al
        moveq   ah, al
        moveq   al, #0

        @ Add initial exponent to sign
        orr     r3, r3, #((127 + 23 + 32) << 23)
        do_it   eq
        subeq   r3, r3, #(32 << 23)
2:      sub     r3, r3, #(1 << 23)

#if __ARM_ARCH__ < 5

        mov     r2, #23
        cmp     ip, #(1 << 16)
        do_it   hs, t
        movhs   ip, ip, lsr #16
        subhs   r2, r2, #16
        cmp     ip, #(1 << 8)
        do_it   hs, t
        movhs   ip, ip, lsr #8
        subhs   r2, r2, #8
        cmp     ip, #(1 << 4)
        do_it   hs, t
        movhs   ip, ip, lsr #4
        subhs   r2, r2, #4
        cmp     ip, #(1 << 2)
        do_it   hs, e
        subhs   r2, r2, #2
        sublo   r2, r2, ip, lsr #1
        subs    r2, r2, ip, lsr #3

#else

        clz     r2, ip
        subs    r2, r2, #8

#endif

        sub     r3, r3, r2, lsl #23
        blt     3f

        shiftop add r3 r3 ah lsl r2 ip
        shift1  lsl, ip, al, r2
        rsb     r2, r2, #32
        cmp     ip, #0x80000000
        shiftop adc r0 r3 al lsr r2 r2
        do_it   eq
        biceq   r0, r0, #1
        RET

3:      add     r2, r2, #32
        shift1  lsl, ip, ah, r2
        rsb     r2, r2, #32
        orrs    al, al, ip, lsl #1
        shiftop adc r0 r3 ah lsr r2 r2
        do_it   eq
        biceq   r0, r0, ip, lsr #31
        RET

#if !defined (__VFP_FP__) && !defined(__SOFTFP__)

LSYM(f0_ret):
        str     r0, [sp, #-4]!
        ldfs    f0, [sp], #4
        RETLDM

#endif

        FUNC_END floatdisf
        FUNC_END aeabi_l2f
        FUNC_END floatundisf
        FUNC_END aeabi_ul2f

#endif /* L_addsubsf3 */

#ifdef L_arm_muldivsf3

ARM_FUNC_START mulsf3
ARM_FUNC_ALIAS aeabi_fmul mulsf3

        @ Mask out exponents, trap any zero/denormal/INF/NAN.
        mov     ip, #0xff
        ands    r2, ip, r0, lsr #23
        do_it   ne, tt
        COND(and,s,ne)  r3, ip, r1, lsr #23
        teqne   r2, ip
        teqne   r3, ip
        beq     LSYM(Lml_s)
LSYM(Lml_x):

        @ Add exponents together
        add     r2, r2, r3

        @ Determine final sign.
        eor     ip, r0, r1

        @ Convert mantissa to unsigned integer.
        @ If power of two, branch to a separate path.
        @ Make up for final alignment.
        movs    r0, r0, lsl #9
        do_it   ne
        COND(mov,s,ne)  r1, r1, lsl #9
        beq     LSYM(Lml_1)
        mov     r3, #0x08000000
        orr     r0, r3, r0, lsr #5
        orr     r1, r3, r1, lsr #5

#if __ARM_ARCH__ < 4

        @ Put sign bit in r3, which will be restored into r0 later.
        and     r3, ip, #0x80000000

        @ Well, no way to make it shorter without the umull instruction.
        do_push {r3, r4, r5}
        mov     r4, r0, lsr #16
        mov     r5, r1, lsr #16
        bic     r0, r0, r4, lsl #16
        bic     r1, r1, r5, lsl #16
        mul     ip, r4, r5
        mul     r3, r0, r1
        mul     r0, r5, r0
        mla     r0, r4, r1, r0
        adds    r3, r3, r0, lsl #16
        adc     r1, ip, r0, lsr #16
        do_pop  {r0, r4, r5}

#else

        @ The actual multiplication.
        umull   r3, r1, r0, r1

        @ Put final sign in r0.
        and     r0, ip, #0x80000000

#endif

        @ Adjust result upon the MSB position.
        cmp     r1, #(1 << 23)
        do_it   cc, tt
        movcc   r1, r1, lsl #1
        orrcc   r1, r1, r3, lsr #31
        movcc   r3, r3, lsl #1

        @ Add sign to result.
        orr     r0, r0, r1

        @ Apply exponent bias, check for under/overflow.
        sbc     r2, r2, #127
        cmp     r2, #(254 - 1)
        bhi     LSYM(Lml_u)

        @ Round the result, merge final exponent.
        cmp     r3, #0x80000000
        adc     r0, r0, r2, lsl #23
        do_it   eq
        biceq   r0, r0, #1
        RET

        @ Multiplication by 0x1p*: let''s shortcut a lot of code.
LSYM(Lml_1):
        teq     r0, #0
        and     ip, ip, #0x80000000
        do_it   eq
        moveq   r1, r1, lsl #9
        orr     r0, ip, r0, lsr #9
        orr     r0, r0, r1, lsr #9
        subs    r2, r2, #127
        do_it   gt, tt
        COND(rsb,s,gt)  r3, r2, #255
        orrgt   r0, r0, r2, lsl #23
        RETc(gt)

        @ Under/overflow: fix things up for the code below.
        orr     r0, r0, #0x00800000
        mov     r3, #0
        subs    r2, r2, #1

LSYM(Lml_u):
        @ Overflow?
        bgt     LSYM(Lml_o)

        @ Check if denormalized result is possible, otherwise return signed 0.
        cmn     r2, #(24 + 1)
        do_it   le, t
        bicle   r0, r0, #0x7fffffff
        RETc(le)

        @ Shift value right, round, etc.
        rsb     r2, r2, #0
        movs    r1, r0, lsl #1
        shift1  lsr, r1, r1, r2
        rsb     r2, r2, #32
        shift1  lsl, ip, r0, r2
        movs    r0, r1, rrx
        adc     r0, r0, #0
        orrs    r3, r3, ip, lsl #1
        do_it   eq
        biceq   r0, r0, ip, lsr #31
        RET

        @ One or both arguments are denormalized.
        @ Scale them leftwards and preserve sign bit.
LSYM(Lml_d):
        teq     r2, #0
        and     ip, r0, #0x80000000
1:      do_it   eq, tt
        moveq   r0, r0, lsl #1
        tsteq   r0, #0x00800000
        subeq   r2, r2, #1
        beq     1b
        orr     r0, r0, ip
        teq     r3, #0
        and     ip, r1, #0x80000000
2:      do_it   eq, tt
        moveq   r1, r1, lsl #1
        tsteq   r1, #0x00800000
        subeq   r3, r3, #1
        beq     2b
        orr     r1, r1, ip
        b       LSYM(Lml_x)

LSYM(Lml_s):
        @ Isolate the INF and NAN cases away
        and     r3, ip, r1, lsr #23
        teq     r2, ip
        do_it   ne
        teqne   r3, ip
        beq     1f

        @ Here, one or more arguments are either denormalized or zero.
        bics    ip, r0, #0x80000000
        do_it   ne
        COND(bic,s,ne)  ip, r1, #0x80000000
        bne     LSYM(Lml_d)

        @ Result is 0, but determine sign anyway.
LSYM(Lml_z):
        eor     r0, r0, r1
        bic     r0, r0, #0x7fffffff
        RET

1:      @ One or both args are INF or NAN.
        teq     r0, #0x0
        do_it   ne, ett
        teqne   r0, #0x80000000
        moveq   r0, r1
        teqne   r1, #0x0
        teqne   r1, #0x80000000
        beq     LSYM(Lml_n)             @ 0 * INF or INF * 0 -> NAN
        teq     r2, ip
        bne     1f
        movs    r2, r0, lsl #9
        bne     LSYM(Lml_n)             @ NAN * <anything> -> NAN
1:      teq     r3, ip
        bne     LSYM(Lml_i)
        movs    r3, r1, lsl #9
        do_it   ne
        movne   r0, r1
        bne     LSYM(Lml_n)             @ <anything> * NAN -> NAN

        @ Result is INF, but we need to determine its sign.
LSYM(Lml_i):
        eor     r0, r0, r1

        @ Overflow: return INF (sign already in r0).
LSYM(Lml_o):
        and     r0, r0, #0x80000000
        orr     r0, r0, #0x7f000000
        orr     r0, r0, #0x00800000
        RET

        @ Return a quiet NAN.
LSYM(Lml_n):
        orr     r0, r0, #0x7f000000
        orr     r0, r0, #0x00c00000
        RET

        FUNC_END aeabi_fmul
        FUNC_END mulsf3

ARM_FUNC_START divsf3
ARM_FUNC_ALIAS aeabi_fdiv divsf3

        @ Mask out exponents, trap any zero/denormal/INF/NAN.
        mov     ip, #0xff
        ands    r2, ip, r0, lsr #23
        do_it   ne, tt
        COND(and,s,ne)  r3, ip, r1, lsr #23
        teqne   r2, ip
        teqne   r3, ip
        beq     LSYM(Ldv_s)
LSYM(Ldv_x):

        @ Substract divisor exponent from dividend''s
        sub     r2, r2, r3

        @ Preserve final sign into ip.
        eor     ip, r0, r1

        @ Convert mantissa to unsigned integer.
        @ Dividend -> r3, divisor -> r1.
        movs    r1, r1, lsl #9
        mov     r0, r0, lsl #9
        beq     LSYM(Ldv_1)
        mov     r3, #0x10000000
        orr     r1, r3, r1, lsr #4
        orr     r3, r3, r0, lsr #4

        @ Initialize r0 (result) with final sign bit.
        and     r0, ip, #0x80000000

        @ Ensure result will land to known bit position.
        @ Apply exponent bias accordingly.
        cmp     r3, r1
        do_it   cc
        movcc   r3, r3, lsl #1
        adc     r2, r2, #(127 - 2)

        @ The actual division loop.
        mov     ip, #0x00800000
1:      cmp     r3, r1
        do_it   cs, t
        subcs   r3, r3, r1
        orrcs   r0, r0, ip
        cmp     r3, r1, lsr #1
        do_it   cs, t
        subcs   r3, r3, r1, lsr #1
        orrcs   r0, r0, ip, lsr #1
        cmp     r3, r1, lsr #2
        do_it   cs, t
        subcs   r3, r3, r1, lsr #2
        orrcs   r0, r0, ip, lsr #2
        cmp     r3, r1, lsr #3
        do_it   cs, t
        subcs   r3, r3, r1, lsr #3
        orrcs   r0, r0, ip, lsr #3
        movs    r3, r3, lsl #4
        do_it   ne
        COND(mov,s,ne)  ip, ip, lsr #4
        bne     1b

        @ Check exponent for under/overflow.
        cmp     r2, #(254 - 1)
        bhi     LSYM(Lml_u)

        @ Round the result, merge final exponent.
        cmp     r3, r1
        adc     r0, r0, r2, lsl #23
        do_it   eq
        biceq   r0, r0, #1
        RET

        @ Division by 0x1p*: let''s shortcut a lot of code.
LSYM(Ldv_1):
        and     ip, ip, #0x80000000
        orr     r0, ip, r0, lsr #9
        adds    r2, r2, #127
        do_it   gt, tt
        COND(rsb,s,gt)  r3, r2, #255
        orrgt   r0, r0, r2, lsl #23
        RETc(gt)

        orr     r0, r0, #0x00800000
        mov     r3, #0
        subs    r2, r2, #1
        b       LSYM(Lml_u)

        @ One or both arguments are denormalized.
        @ Scale them leftwards and preserve sign bit.
LSYM(Ldv_d):
        teq     r2, #0
        and     ip, r0, #0x80000000
1:      do_it   eq, tt
        moveq   r0, r0, lsl #1
        tsteq   r0, #0x00800000
        subeq   r2, r2, #1
        beq     1b
        orr     r0, r0, ip
        teq     r3, #0
        and     ip, r1, #0x80000000
2:      do_it   eq, tt
        moveq   r1, r1, lsl #1
        tsteq   r1, #0x00800000
        subeq   r3, r3, #1
        beq     2b
        orr     r1, r1, ip
        b       LSYM(Ldv_x)

        @ One or both arguments are either INF, NAN, zero or denormalized.
LSYM(Ldv_s):
        and     r3, ip, r1, lsr #23
        teq     r2, ip
        bne     1f
        movs    r2, r0, lsl #9
        bne     LSYM(Lml_n)             @ NAN / <anything> -> NAN
        teq     r3, ip
        bne     LSYM(Lml_i)             @ INF / <anything> -> INF
        mov     r0, r1
        b       LSYM(Lml_n)             @ INF / (INF or NAN) -> NAN
1:      teq     r3, ip
        bne     2f
        movs    r3, r1, lsl #9
        beq     LSYM(Lml_z)             @ <anything> / INF -> 0
        mov     r0, r1
        b       LSYM(Lml_n)             @ <anything> / NAN -> NAN
2:      @ If both are nonzero, we need to normalize and resume above.
        bics    ip, r0, #0x80000000
        do_it   ne
        COND(bic,s,ne)  ip, r1, #0x80000000
        bne     LSYM(Ldv_d)
        @ One or both arguments are zero.
        bics    r2, r0, #0x80000000
        bne     LSYM(Lml_i)             @ <non_zero> / 0 -> INF
        bics    r3, r1, #0x80000000
        bne     LSYM(Lml_z)             @ 0 / <non_zero> -> 0
        b       LSYM(Lml_n)             @ 0 / 0 -> NAN

        FUNC_END aeabi_fdiv
        FUNC_END divsf3

#endif /* L_muldivsf3 */

#ifdef L_arm_cmpsf2

        @ The return value in r0 is
        @
        @   0  if the operands are equal
        @   1  if the first operand is greater than the second, or
        @      the operands are unordered and the operation is
        @      CMP, LT, LE, NE, or EQ.
        @   -1 if the first operand is less than the second, or
        @      the operands are unordered and the operation is GT
        @      or GE.
        @
        @ The Z flag will be set iff the operands are equal.
        @
        @ The following registers are clobbered by this function:
        @   ip, r0, r1, r2, r3

ARM_FUNC_START gtsf2
ARM_FUNC_ALIAS gesf2 gtsf2
        mov     ip, #-1
        b       1f

ARM_FUNC_START ltsf2
ARM_FUNC_ALIAS lesf2 ltsf2
        mov     ip, #1
        b       1f

ARM_FUNC_START cmpsf2
ARM_FUNC_ALIAS nesf2 cmpsf2
ARM_FUNC_ALIAS eqsf2 cmpsf2
        mov     ip, #1                  @ how should we specify unordered here?

1:      str     ip, [sp, #-4]!

        @ Trap any INF/NAN first.
        mov     r2, r0, lsl #1
        mov     r3, r1, lsl #1
        mvns    ip, r2, asr #24
        do_it   ne
        COND(mvn,s,ne)  ip, r3, asr #24
        beq     3f

        @ Compare values.
        @ Note that 0.0 is equal to -0.0.
2:      add     sp, sp, #4
        orrs    ip, r2, r3, lsr #1      @ test if both are 0, clear C flag
        do_it   ne
        teqne   r0, r1                  @ if not 0 compare sign
        do_it   pl
        COND(sub,s,pl)  r0, r2, r3              @ if same sign compare values, set r0

        @ Result:
        do_it   hi
        movhi   r0, r1, asr #31
        do_it   lo
        mvnlo   r0, r1, asr #31
        do_it   ne
        orrne   r0, r0, #1
        RET

        @ Look for a NAN. 
3:      mvns    ip, r2, asr #24
        bne     4f
        movs    ip, r0, lsl #9
        bne     5f                      @ r0 is NAN
4:      mvns    ip, r3, asr #24
        bne     2b
        movs    ip, r1, lsl #9
        beq     2b                      @ r1 is not NAN
5:      ldr     r0, [sp], #4            @ return unordered code.
        RET

        FUNC_END gesf2
        FUNC_END gtsf2
        FUNC_END lesf2
        FUNC_END ltsf2
        FUNC_END nesf2
        FUNC_END eqsf2
        FUNC_END cmpsf2

ARM_FUNC_START aeabi_cfrcmple

        mov     ip, r0
        mov     r0, r1
        mov     r1, ip
        b       6f

ARM_FUNC_START aeabi_cfcmpeq
ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq

        @ The status-returning routines are required to preserve all
        @ registers except ip, lr, and cpsr.
6:      do_push {r0, r1, r2, r3, lr}
        ARM_CALL cmpsf2
        @ Set the Z flag correctly, and the C flag unconditionally.
        cmp     r0, #0
        @ Clear the C flag if the return value was -1, indicating
        @ that the first operand was smaller than the second.
        do_it   mi
        cmnmi   r0, #0
        RETLDM  "r0, r1, r2, r3"

        FUNC_END aeabi_cfcmple
        FUNC_END aeabi_cfcmpeq
        FUNC_END aeabi_cfrcmple

ARM_FUNC_START  aeabi_fcmpeq

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        do_it   eq, e
        moveq   r0, #1  @ Equal to.
        movne   r0, #0  @ Less than, greater than, or unordered.
        RETLDM

        FUNC_END aeabi_fcmpeq

ARM_FUNC_START  aeabi_fcmplt

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        do_it   cc, e
        movcc   r0, #1  @ Less than.
        movcs   r0, #0  @ Equal to, greater than, or unordered.
        RETLDM

        FUNC_END aeabi_fcmplt

ARM_FUNC_START  aeabi_fcmple

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        do_it   ls, e
        movls   r0, #1  @ Less than or equal to.
        movhi   r0, #0  @ Greater than or unordered.
        RETLDM

        FUNC_END aeabi_fcmple

ARM_FUNC_START  aeabi_fcmpge

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfrcmple
        do_it   ls, e
        movls   r0, #1  @ Operand 2 is less than or equal to operand 1.
        movhi   r0, #0  @ Operand 2 greater than operand 1, or unordered.
        RETLDM

        FUNC_END aeabi_fcmpge

ARM_FUNC_START  aeabi_fcmpgt

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfrcmple
        do_it   cc, e
        movcc   r0, #1  @ Operand 2 is less than operand 1.
        movcs   r0, #0  @ Operand 2 is greater than or equal to operand 1,
                        @ or they are unordered.
        RETLDM

        FUNC_END aeabi_fcmpgt

#endif /* L_cmpsf2 */

#ifdef L_arm_unordsf2

ARM_FUNC_START unordsf2
ARM_FUNC_ALIAS aeabi_fcmpun unordsf2

        mov     r2, r0, lsl #1
        mov     r3, r1, lsl #1
        mvns    ip, r2, asr #24
        bne     1f
        movs    ip, r0, lsl #9
        bne     3f                      @ r0 is NAN
1:      mvns    ip, r3, asr #24
        bne     2f
        movs    ip, r1, lsl #9
        bne     3f                      @ r1 is NAN
2:      mov     r0, #0                  @ arguments are ordered.
        RET
3:      mov     r0, #1                  @ arguments are unordered.
        RET

        FUNC_END aeabi_fcmpun
        FUNC_END unordsf2

#endif /* L_unordsf2 */

#ifdef L_arm_fixsfsi

ARM_FUNC_START fixsfsi
ARM_FUNC_ALIAS aeabi_f2iz fixsfsi

        @ check exponent range.
        mov     r2, r0, lsl #1
        cmp     r2, #(127 << 24)
        bcc     1f                      @ value is too small
        mov     r3, #(127 + 31)
        subs    r2, r3, r2, lsr #24
        bls     2f                      @ value is too large

        @ scale value
        mov     r3, r0, lsl #8
        orr     r3, r3, #0x80000000
        tst     r0, #0x80000000         @ the sign bit
        shift1  lsr, r0, r3, r2
        do_it   ne
        rsbne   r0, r0, #0
        RET

1:      mov     r0, #0
        RET

2:      cmp     r2, #(127 + 31 - 0xff)
        bne     3f
        movs    r2, r0, lsl #9
        bne     4f                      @ r0 is NAN.
3:      ands    r0, r0, #0x80000000     @ the sign bit
        do_it   eq
        moveq   r0, #0x7fffffff         @ the maximum signed positive si
        RET

4:      mov     r0, #0                  @ What should we convert NAN to?
        RET

        FUNC_END aeabi_f2iz
        FUNC_END fixsfsi

#endif /* L_fixsfsi */

#ifdef L_arm_fixunssfsi

ARM_FUNC_START fixunssfsi
ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi

        @ check exponent range.
        movs    r2, r0, lsl #1
        bcs     1f                      @ value is negative
        cmp     r2, #(127 << 24)
        bcc     1f                      @ value is too small
        mov     r3, #(127 + 31)
        subs    r2, r3, r2, lsr #24
        bmi     2f                      @ value is too large

        @ scale the value
        mov     r3, r0, lsl #8
        orr     r3, r3, #0x80000000
        shift1  lsr, r0, r3, r2
        RET

1:      mov     r0, #0
        RET

2:      cmp     r2, #(127 + 31 - 0xff)
        bne     3f
        movs    r2, r0, lsl #9
        bne     4f                      @ r0 is NAN.
3:      mov     r0, #0xffffffff         @ maximum unsigned si
        RET

4:      mov     r0, #0                  @ What should we convert NAN to?
        RET

        FUNC_END aeabi_f2uiz
        FUNC_END fixunssfsi

#endif /* L_fixunssfsi */