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Diffstat (limited to 'libm/arm/s_floor.S')
| -rw-r--r-- | libm/arm/s_floor.S | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/libm/arm/s_floor.S b/libm/arm/s_floor.S new file mode 100644 index 0000000..3af8f76 --- /dev/null +++ b/libm/arm/s_floor.S @@ -0,0 +1,139 @@ +/* + * Copyright (c) 2013-2014, NVIDIA Corporation. All rights reserved. + * Johnny Qiu <joqiu@nvidia.com> + * Shu Zhang <chazhang@nvidia.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of The Linux Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <float.h> +#include <private/bionic_asm.h> + +ENTRY(floor) /* x in r0, r1 */ + + and r3, r1, #0x80000000 /* sign(x) */ + bic r1, r1, #0x80000000 /* x = abs(x) */ + + /* extract exp of x */ + lsr r2, r1, #20 + sub r2, r2, #0x3fc + subs r2, r2, #0x3 /* r2 <- exp */ + + /* |x| < 1.0? */ + blt .Lx_lt_one + + /* x < 0? */ + cmp r3, #0 + bne .Lclr_frac_neg + + /* |x| <= 2^20? */ + cmp r2, #20 + ble .Lclr_frac_r1 + + /* |x| < 2^52? */ + cmp r2, #52 + blt .Lclr_frac_r0 + + /* return x */ + bx lr + +.Lclr_frac_r1: + rsb r2, r2, #20 + lsr r1, r1, r2 + lsl r1, r1, r2 + mov r0, #0 + bx lr + +.Lclr_frac_r0: + rsb r2, r2, #52 + lsr r0, r0, r2 + lsl r0, r0, r2 + bx lr + +.Lclr_frac_neg: + /* |x| <= 2^20? */ + cmp r2, #20 + ble .Lclr_frac_r1_neg + + /* |x| < 2^52? */ + cmp r2, #52 + blt .Lclr_frac_r0_neg + + /* return x */ + orr r1, r1, #0x80000000 + bx lr + +.Lclr_frac_r1_neg: + rsb r2, r2, #20 + mov r3, #1 + lsl r3, r3, r2 + sub r3, r3, #1 + and r3, r1, r3 + orr r3, r3, r0 + lsr r1, r1, r2 + lsl r1, r1, r2 + mov r0, #0 + b .Lreturn_x_neg + +.Lclr_frac_r0_neg: + rsb r2, r2, #52 + mov r3, #1 + lsl r3, r3, r2 + sub r3, r3, #1 + and r3, r0, r3 + lsr r0, r0, r2 + lsl r0, r0, r2 + b .Lreturn_x_neg + +.Lx_lt_one: + /* x == +-0? */ + cmp r0, #0 + cmpeq r1, #0 + orreq r1, r1, r3 + bxeq lr + + /* (x > 0) ? 0 : -1 */ + mov r1, #0x00100000 + mov r0, #0 + cmp r3, #0 + movne r1, #0xc0000000 + sub r1, r1, #0x00100000 + bx lr + +.Lreturn_x_neg: + cmp r3, #0 + orr r1, r1, #0x80000000 + bxeq lr + + vmov d16, r0, r1 + vmov.f64 d18, #1.0 + vsub.f64 d16, d16, d18 + vmov r0, r1, d16 + bx lr + +END(floor) + +ALIAS_SYMBOL(floorl, floor); |