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|
/* ieee754-sf.S single-precision floating point support for ARM
Copyright (C) 2003-2016 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.
*
* In the CFI related comments, 'previousOffset' refers to the previous offset
* from sp used to compute the CFA.
*/
#ifdef L_arm_negsf2
ARM_FUNC_START negsf2
ARM_FUNC_ALIAS aeabi_fneg negsf2
CFI_START_FUNCTION
eor r0, r0, #0x80000000 @ flip sign bit
RET
CFI_END_FUNCTION
FUNC_END aeabi_fneg
FUNC_END negsf2
#endif
#ifdef L_arm_addsubsf3
ARM_FUNC_START aeabi_frsub
CFI_START_FUNCTION
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
CFI_END_FUNCTION
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
CFI_START_FUNCTION
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
CFI_END_FUNCTION
FUNC_END aeabi_i2f
FUNC_END floatsisf
FUNC_END aeabi_ui2f
FUNC_END floatunsisf
ARM_FUNC_START floatundisf
ARM_FUNC_ALIAS aeabi_ul2f floatundisf
CFI_START_FUNCTION
orrs r2, r0, r1
do_it eq
RETc(eq)
mov r3, #0
b 1f
ARM_FUNC_START floatdisf
ARM_FUNC_ALIAS aeabi_l2f floatdisf
orrs r2, r0, r1
do_it eq
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:
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
CFI_END_FUNCTION
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
CFI_START_FUNCTION
@ 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} @ sp -= 12
.cfi_remember_state @ Save the current CFI state
.cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12
.cfi_rel_offset r3, 0 @ Registers are saved from sp to sp + 8
.cfi_rel_offset r4, 4
.cfi_rel_offset r5, 8
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} @ sp += 12
.cfi_restore_state @ Restore the previous CFI state
#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
CFI_END_FUNCTION
FUNC_END aeabi_fmul
FUNC_END mulsf3
ARM_FUNC_START divsf3
ARM_FUNC_ALIAS aeabi_fdiv divsf3
CFI_START_FUNCTION
@ 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):
@ Subtract 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
CFI_END_FUNCTION
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
CFI_START_FUNCTION
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]!
.cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4.
@ We're not adding CFI for ip as it's pushed into the stack only because
@ it may be popped off later as a return value (i.e. we're not preserving
@ it anyways).
@ 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
.cfi_remember_state
@ Save the current CFI state. This is done because the branch is conditional,
@ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return.
@ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch
@ code will affect the branch code as well. To avoid this we'll restore
@ the current state before executing the branch code.
@ Compare values.
@ Note that 0.0 is equal to -0.0.
2: add sp, sp, #4
.cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset.
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
3: @ Look for a NAN.
@ Restore the previous CFI state (i.e. keep the CFI state as it was
@ before the branch).
.cfi_restore_state
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.
.cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset.
RET
CFI_END_FUNCTION
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
CFI_START_FUNCTION
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}
.cfi_adjust_cfa_offset 20 @ CFA is at sp + previousOffset + 20
.cfi_rel_offset r0, 0 @ Registers are saved from sp to sp + 16
.cfi_rel_offset r1, 4
.cfi_rel_offset r2, 8
.cfi_rel_offset r3, 12
.cfi_rel_offset lr, 16
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"
CFI_END_FUNCTION
FUNC_END aeabi_cfcmple
FUNC_END aeabi_cfcmpeq
FUNC_END aeabi_cfrcmple
ARM_FUNC_START aeabi_fcmpeq
CFI_START_FUNCTION
str lr, [sp, #-8]! @ sp -= 8
.cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8
.cfi_rel_offset lr, 0 @ lr is at sp
ARM_CALL aeabi_cfcmple
do_it eq, e
moveq r0, #1 @ Equal to.
movne r0, #0 @ Less than, greater than, or unordered.
RETLDM
CFI_END_FUNCTION
FUNC_END aeabi_fcmpeq
ARM_FUNC_START aeabi_fcmplt
CFI_START_FUNCTION
str lr, [sp, #-8]! @ sp -= 8
.cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8
.cfi_rel_offset lr, 0 @ lr is at sp
ARM_CALL aeabi_cfcmple
do_it cc, e
movcc r0, #1 @ Less than.
movcs r0, #0 @ Equal to, greater than, or unordered.
RETLDM
CFI_END_FUNCTION
FUNC_END aeabi_fcmplt
ARM_FUNC_START aeabi_fcmple
CFI_START_FUNCTION
str lr, [sp, #-8]! @ sp -= 8
.cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8
.cfi_rel_offset lr, 0 @ lr is at sp
ARM_CALL aeabi_cfcmple
do_it ls, e
movls r0, #1 @ Less than or equal to.
movhi r0, #0 @ Greater than or unordered.
RETLDM
CFI_END_FUNCTION
FUNC_END aeabi_fcmple
ARM_FUNC_START aeabi_fcmpge
CFI_START_FUNCTION
str lr, [sp, #-8]! @ sp -= 8
.cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8
.cfi_rel_offset lr, 0 @ lr is at sp
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
CFI_END_FUNCTION
FUNC_END aeabi_fcmpge
ARM_FUNC_START aeabi_fcmpgt
CFI_START_FUNCTION
str lr, [sp, #-8]! @ sp -= 8
.cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8
.cfi_rel_offset lr, 0 @ lr is at sp
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
CFI_END_FUNCTION
FUNC_END aeabi_fcmpgt
#endif /* L_cmpsf2 */
#ifdef L_arm_unordsf2
ARM_FUNC_START unordsf2
ARM_FUNC_ALIAS aeabi_fcmpun unordsf2
CFI_START_FUNCTION
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
CFI_END_FUNCTION
FUNC_END aeabi_fcmpun
FUNC_END unordsf2
#endif /* L_unordsf2 */
#ifdef L_arm_fixsfsi
ARM_FUNC_START fixsfsi
ARM_FUNC_ALIAS aeabi_f2iz fixsfsi
CFI_START_FUNCTION
@ 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
CFI_END_FUNCTION
FUNC_END aeabi_f2iz
FUNC_END fixsfsi
#endif /* L_fixsfsi */
#ifdef L_arm_fixunssfsi
ARM_FUNC_START fixunssfsi
ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi
CFI_START_FUNCTION
@ 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
CFI_END_FUNCTION
FUNC_END aeabi_f2uiz
FUNC_END fixunssfsi
#endif /* L_fixunssfsi */
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