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Diffstat (limited to 'sysdeps/ia64/fpu/s_nearbyint.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_nearbyint.S | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/sysdeps/ia64/fpu/s_nearbyint.S b/sysdeps/ia64/fpu/s_nearbyint.S new file mode 100644 index 0000000000..8c7e4a9ec9 --- /dev/null +++ b/sysdeps/ia64/fpu/s_nearbyint.S @@ -0,0 +1,221 @@ +.file "nearbyint.s" + +// Copyright (c) 2000, 2001, Intel Corporation +// All rights reserved. +// +// Contributed 10/19/2000 by John Harrison, Cristina Iordache, Ted Kubaska, +// Bob Norin, Tom Rowan, 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. +// +// History +//============================================================== +// 10/19/2000: Created +// 2/08/01 Corrected behavior for all rounding modes. +//============================================================== +// +// API +//============================================================== +// double nearbyint(double x) + +#include "libm_support.h" + +// +// general registers used: +// + +nearbyint_GR_signexp = r14 +nearbyint_GR_exponent = r15 +nearbyint_GR_17ones = r16 +nearbyint_GR_10033 = r17 +nearbyint_GR_fpsr = r18 +nearbyint_GR_rcs0 = r19 +nearbyint_GR_rcs0_mask = r20 + + +// predicate registers used: +// p6-11 + +// floating-point registers used: + +NEARBYINT_NORM_f8 = f9 +NEARBYINT_FLOAT_INT_f8 = f10 +NEARBYINT_INT_f8 = f11 + +// Overview of operation +//============================================================== + +// double nearbyint(double x) +// Return an integer value (represented as a double) that is x rounded to integer in current +// rounding mode +// ******************************************************************************* + +// 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 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. + +// If x is NAN, ZERO, or INFINITY, then return + +// qnan snan inf norm unorm 0 -+ +// 1 1 1 0 0 1 11 0xe7 + + +.align 32 +.global nearbyint# + +.section .text +.proc nearbyint# +.align 32 + + +nearbyint: + +{ .mfi + mov nearbyint_GR_fpsr = ar40 // Read the fpsr--need to check rc.s0 + fcvt.fx.s1 NEARBYINT_INT_f8 = f8 + addl nearbyint_GR_10033 = 0x10033, r0 +} +{ .mfi + nop.m 999 + fnorm.s1 NEARBYINT_NORM_f8 = f8 + mov nearbyint_GR_17ones = 0x1FFFF +;; +} + +{ .mfi + nop.m 999 + fclass.m.unc p6,p0 = f8, 0xe7 + mov nearbyint_GR_rcs0_mask = 0x0c00 +;; +} + +{ .mfb + nop.m 999 +(p6) fnorm.d f8 = f8 +(p6) br.ret.spnt b0 // Exit if x nan, inf, zero +;; +} + +{ .mfi + nop.m 999 + fcvt.xf NEARBYINT_FLOAT_INT_f8 = NEARBYINT_INT_f8 + nop.i 999 +;; +} + +{ .mfi + getf.exp nearbyint_GR_signexp = NEARBYINT_NORM_f8 + fcmp.eq.s0 p8,p0 = f8,f0 // Dummy op to set denormal + nop.i 999 +;; +} + + +{ .mii + nop.m 999 + nop.i 999 + and nearbyint_GR_exponent = nearbyint_GR_signexp, nearbyint_GR_17ones +;; +} + +{ .mmi + cmp.ge.unc p7,p6 = nearbyint_GR_exponent, nearbyint_GR_10033 + and nearbyint_GR_rcs0 = nearbyint_GR_rcs0_mask, nearbyint_GR_fpsr + nop.i 999 +;; +} + +// Check to see if s0 rounding mode is round to nearest. If not then set s2 +// rounding mode to that of s0 and repeat conversions. +L(NEARBYINT_COMMON): +{ .mfb + cmp.ne p11,p0 = nearbyint_GR_rcs0, r0 +(p6) fclass.m.unc p9,p10 = NEARBYINT_FLOAT_INT_f8, 0x07 // Test for result=0 +(p11) br.cond.spnt L(NEARBYINT_NOT_ROUND_NEAREST) // Branch if not round to nearest +;; +} + +{ .mfi + nop.m 999 +(p7) fnorm.d.s0 f8 = f8 + nop.i 999 +;; +} + +// If result is zero, merge sign of input +{ .mfi + nop.m 999 +(p9) fmerge.s f8 = f8, NEARBYINT_FLOAT_INT_f8 + nop.i 999 +} +{ .mfb + nop.m 999 +(p10) fnorm.d f8 = NEARBYINT_FLOAT_INT_f8 + br.ret.sptk b0 +;; +} + + +L(NEARBYINT_NOT_ROUND_NEAREST): +// Set rounding mode of s2 to that of s0 +{ .mfi + mov nearbyint_GR_rcs0 = r0 // Clear so we don't come back here + fsetc.s2 0x7f, 0x40 + nop.i 999 +;; +} + +{ .mfi + nop.m 999 + fcvt.fx.s2 NEARBYINT_INT_f8 = f8 + nop.i 999 +;; +} + +{ .mfb + nop.m 999 + fcvt.xf NEARBYINT_FLOAT_INT_f8 = NEARBYINT_INT_f8 + br.cond.sptk L(NEARBYINT_COMMON) +;; +} + + +.endp nearbyint +ASM_SIZE_DIRECTIVE(nearbyint) |