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Diffstat (limited to 'sysdeps/ia64/fpu/s_floor.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_floor.S | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/sysdeps/ia64/fpu/s_floor.S b/sysdeps/ia64/fpu/s_floor.S new file mode 100644 index 0000000000..5a63a3c263 --- /dev/null +++ b/sysdeps/ia64/fpu/s_floor.S @@ -0,0 +1,227 @@ +.file "floor.s" + +// Copyright (c) 2000, 2001, Intel Corporation +// All rights reserved. +// +// Contributed 2/2/2000 by John Harrison, Ted Kubaska, Bob Norin, Shane Story, +// and Ping Tak Peter Tang of the Computational Software Lab, Intel Corporation. +// +// WARRANTY DISCLAIMER +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS +// 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. +// +// Intel Corporation is the author of this code, and requests that all +// problem reports or change requests be submitted to it directly at +// http://developer.intel.com/opensource. +// +.align 32 +.global floor# + +.section .text +.proc floor# +.align 32 + +// History +//============================================================== +// 2/02/00: Initial version +// 3/22/00: Updated to improve performance +// 6/13/00: Improved speed, fixed setting of inexact flag +// 6/27/00: Eliminated incorrect invalid flag setting +// 2/07/01: Corrected sign of zero result in round to -inf mode + +// API +//============================================================== +// double floor(double x) + +// general input registers: + +floor_GR_FFFF = r14 +floor_GR_signexp = r15 +floor_GR_exponent = r16 +floor_GR_expmask = r17 +floor_GR_bigexp = r18 + + +// predicate registers used: + +// p6 ==> Input is NaN, infinity, zero +// p7 ==> Input is denormal +// p8 ==> Input is <0 +// p9 ==> Input is >=0 +// p10 ==> Input is already an integer (bigger than largest integer) +// p11 ==> Input is not a large integer +// p12 ==> Input is a smaller integer +// p13 ==> Input is not an even integer, so inexact must be set + + +// floating-point registers used: + +FLOOR_NORM_f8 = f9 +FLOOR_FFFF = f10 +FLOOR_INEXACT = f11 +FLOOR_FLOAT_INT_f8 = f12 +FLOOR_INT_f8 = f13 +FLOOR_adj = f14 + +// Overview of operation +//============================================================== + +// double floor(double x) +// Return an integer value (represented as a double) that is the largest +// value not greater than x +// This is x rounded toward -infinity to an integral value. +// Inexact is set if x != floor(x) +// ************************************************************************** + +// Set denormal flag for denormal input and +// and take denormal fault if necessary. + +// Is the input an integer value already? + +// double_extended +// if the exponent is > 1003e => 3F(true) = 63(decimal) +// we have a significand of 64 bits 1.63-bits. +// If we multiply by 2^63, we no longer have a fractional part +// So input is an integer value already. + +// double +// if the exponent is >= 10033 => 34(true) = 52(decimal) +// 34 + 3ff = 433 +// we have a significand of 53 bits 1.52-bits. (implicit 1) +// If we multiply by 2^52, we no longer have a fractional part +// So input is an integer value already. + +// single +// if the exponent is > 10016 => 17(true) = 23(decimal) +// we have a significand of 24 bits 1.23-bits. (implicit 1) +// If we multiply by 2^23, we no longer have a fractional part +// So input is an integer value already. + +// If x is NAN, ZERO, or INFINITY, then return + +// qnan snan inf norm unorm 0 -+ +// 1 1 1 0 0 1 11 0xe7 + +#include "libm_support.h" + +floor: +#ifdef _LIBC +.global __floor +__floor: +#endif + +{ .mfi + getf.exp floor_GR_signexp = f8 + fcvt.fx.trunc.s1 FLOOR_INT_f8 = f8 + addl floor_GR_bigexp = 0x10033, r0 +} +{ .mfi + addl floor_GR_FFFF = -1,r0 + fcmp.lt.s1 p8,p9 = f8,f0 + mov floor_GR_expmask = 0x1FFFF ;; +} + +// p7 ==> denorm +{ .mfi + setf.sig FLOOR_FFFF = floor_GR_FFFF + fclass.m p7,p0 = f8, 0x0b + nop.i 999 +} +{ .mfi + nop.m 999 + fnorm.s1 FLOOR_NORM_f8 = f8 + nop.i 999 ;; +} + +// p6 ==> NAN, INF, ZERO +{ .mfb + nop.m 999 + fclass.m p6,p10 = f8, 0xe7 +(p7) br.cond.spnt L(FLOOR_DENORM) ;; +} + +L(FLOOR_COMMON): +.pred.rel "mutex",p8,p9 +// Set adjustment to subtract from trunc(x) for result +// If x<0, adjustment is -1.0 +// If x>=0, adjustment is 0.0 +{ .mfi + and floor_GR_exponent = floor_GR_signexp, floor_GR_expmask +(p8) fnma.s1 FLOOR_adj = f1,f1,f0 + nop.i 999 +} +{ .mfi + nop.m 999 +(p9) fadd.s1 FLOOR_adj = f0,f0 + nop.i 999 ;; +} + +{ .mfi + nop.m 999 + fcmp.eq.s0 p12,p0 = f8,f0 // Dummy op to set denormal and invalid flag + nop.i 999 +} +{ .mfi +(p10) cmp.ge.unc p10,p11 = floor_GR_exponent, floor_GR_bigexp +(p6) fnorm.d f8 = f8 + nop.i 999 ;; +} + +{ .mfi + nop.m 999 +(p11) fcvt.xf FLOOR_FLOAT_INT_f8 = FLOOR_INT_f8 + nop.i 999 ;; +} + +{ .mfi + nop.m 999 +(p10) fnorm.d f8 = FLOOR_NORM_f8 + nop.i 999 ;; +} + + +{ .mfi + nop.m 999 +(p11) fadd.d f8 = FLOOR_FLOAT_INT_f8,FLOOR_adj + nop.i 999 ;; +} + +{ .mfi + nop.m 999 +(p11) fcmp.eq.unc.s1 p12,p13 = FLOOR_FLOAT_INT_f8, FLOOR_NORM_f8 + nop.i 999 ;; +} + +// Set inexact if result not equal to input +{ .mfi + nop.m 999 +(p13) fmpy.s0 FLOOR_INEXACT = FLOOR_FFFF,FLOOR_FFFF + nop.i 999 +} +// Set result to input if integer +{ .mfb + nop.m 999 +(p12) fnorm.d f8 = FLOOR_NORM_f8 + br.ret.sptk b0 ;; +} + +// Here if input denorm +L(FLOOR_DENORM): +{ .mfb + getf.exp floor_GR_signexp = FLOOR_NORM_f8 + fcvt.fx.trunc.s1 FLOOR_INT_f8 = FLOOR_NORM_f8 + br.cond.sptk L(FLOOR_COMMON) ;; +} + +.endp floor +ASM_SIZE_DIRECTIVE(floor) |