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Diffstat (limited to 'sysdeps/ia64/fpu/s_round.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_round.S | 322 |
1 files changed, 169 insertions, 153 deletions
diff --git a/sysdeps/ia64/fpu/s_round.S b/sysdeps/ia64/fpu/s_round.S index ed5ffae205..b08ede1740 100644 --- a/sysdeps/ia64/fpu/s_round.S +++ b/sysdeps/ia64/fpu/s_round.S @@ -1,10 +1,11 @@ .file "round.s" - -// Copyright (c) 2000 - 2003, Intel Corporation +// Copyright (C) 2000, 2001, Intel Corporation // All rights reserved. -// -// Contributed 2000 by the Intel Numerics Group, Intel Corporation +// +// Contributed 10/25/2000 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. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are @@ -20,214 +21,229 @@ // * The name of Intel Corporation may not be used to endorse or promote // products derived from this software without specific prior written // permission. - -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// +// 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 +// 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 +// 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. -// +// 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://www.intel.com/software/products/opensource/libraries/num.htm. +// problem reports or change requests be submitted to it directly at +// http://developer.intel.com/opensource. // // History //============================================================== -// 10/25/00 Initial version -// 06/14/01 Changed cmp to an equivalent form -// 05/20/02 Cleaned up namespace and sf0 syntax -// 01/20/03 Improved performance and reduced code size -// 04/18/03 Eliminate possible WAW dependency warning -// 09/03/03 Improved performance +// 10/25/2000: Created //============================================================== - +// // API //============================================================== // double round(double x) -//============================================================== - -// general input registers: -// r14 - r18 +// -rSignexp = r14 -rExp = r15 -rExpMask = r16 -rBigexp = r17 -rExpHalf = r18 +#include "libm_support.h" -// floating-point registers: -// f8 - f13 +// general input registers: +// +round_GR_half = r14 +round_GR_big = r15 +round_GR_expmask = r16 +round_GR_signexp = r17 +round_GR_exp = r18 +round_GR_expdiff = r19 + +// predicate registers used: +// p6 - p10 -fXtruncInt = f9 -fNormX = f10 -fHalf = f11 -fInc = f12 -fRem = f13 +// floating-point registers used: -// predicate registers used: -// p6 - p10 +ROUND_NORM_f8 = f9 +ROUND_TRUNC_f8 = f10 +ROUND_RINT_f8 = f11 +ROUND_FLOAT_TRUNC_f8 = f12 +ROUND_FLOAT_RINT_f8 = f13 +ROUND_REMAINDER = f14 +ROUND_HALF = f15 // Overview of operation //============================================================== + // double round(double x) -// Return an integer value (represented as a double) that is x -// rounded to nearest integer, halfway cases rounded away from -// zero. +// Return an integer value (represented as a double) that is x +// rounded to nearest integer, halfway cases rounded away from +// zero. // if x>0 result = trunc(x+0.5) // if x<0 result = trunc(x-0.5) -// -//============================================================== +// ******************************************************************************* -// 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. +// Set denormal flag for denormal input and +// and take denormal fault if necessary. -// 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. +// If x is NAN, ZERO, INFINITY, or >= 2^52 then return -// 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. +// qnan snan inf norm unorm 0 -+ +// 1 1 1 0 0 1 11 0xe7 +.align 32 +.global round# + .section .text -GLOBAL_LIBM_ENTRY(round) +.proc round# +.align 32 + +round: + +// Get exponent for +0.5 +// Truncate x to integer { .mfi - getf.exp rSignexp = f8 // Get signexp, recompute if unorm - fcvt.fx.trunc.s1 fXtruncInt = f8 // Convert to int in significand - addl rBigexp = 0x10033, r0 // Set exponent at which is integer -} + addl round_GR_half = 0x0fffe, r0 + fcvt.fx.trunc.s1 ROUND_TRUNC_f8 = f8 + nop.i 999 +} + +// Get signexp of x +// Normalize input +// Form exponent mask { .mfi - mov rExpHalf = 0x0FFFE // Form sign and exponent of 0.5 - fnorm.s1 fNormX = f8 // Normalize input - mov rExpMask = 0x1FFFF // Form exponent mask + getf.exp round_GR_signexp = f8 + fnorm ROUND_NORM_f8 = f8 + addl round_GR_expmask = 0x1ffff, r0 ;; } -;; +// Form +0.5 +// Round x to integer { .mfi - setf.exp fHalf = rExpHalf // Form 0.5 - fclass.m p7,p0 = f8, 0x0b // Test x unorm - nop.i 0 -} -;; - -{ .mfb - nop.m 0 - fclass.m p6,p0 = f8, 0x1e3 // Test x natval, nan, inf -(p7) br.cond.spnt ROUND_UNORM // Branch if x unorm + setf.exp ROUND_HALF = round_GR_half + fcvt.fx.s1 ROUND_RINT_f8 = f8 + nop.i 999 ;; } -;; - -ROUND_COMMON: -// Return here from ROUND_UNORM -{ .mfb - nop.m 0 - fcmp.lt.s1 p8,p9 = f8, f0 // Test if x < 0 -(p6) br.cond.spnt ROUND_SPECIAL // Exit if x natval, nan, inf +// Get exp of x +// Test for NAN, INF, ZERO +// Get exponent at which input has no fractional part +{ .mfi + and round_GR_exp = round_GR_expmask, round_GR_signexp + fclass.m p8,p9 = f8,0xe7 + addl round_GR_big = 0x10033, r0 ;; } -;; +// Get exp-bigexp +// If exp is so big there is no fractional part, then turn on p8, off p9 +{ .mmi + sub round_GR_expdiff = round_GR_exp, round_GR_big ;; +#ifdef _LIBC +(p9) cmp.lt.or.andcm p8,p9 = r0, round_GR_expdiff +#else +(p9) cmp.ge.or.andcm p8,p9 = round_GR_expdiff, r0 +#endif + nop.i 999 ;; +} + +// Set p6 if x<0, else set p7 { .mfi - nop.m 0 - fcvt.xf f8 = fXtruncInt // Pre-Result if 0.5 <= |x| < 2^52 - nop.i 0 + nop.m 999 +(p9) fcmp.lt.unc p6,p7 = f8,f0 + nop.i 999 } -;; - + +// If NAN, INF, ZERO, or no fractional part, result is just normalized input { .mfi - and rExp = rSignexp, rExpMask // Get biased exponent - fmerge.s fInc = fNormX, f1 // Form increment if |rem| >= 0.5 - nop.i 0 + nop.m 999 +(p8) fnorm.d.s0 f8 = f8 + nop.i 999 ;; } -;; -{ .mmi - cmp.lt p6,p0 = rExp, rExpHalf // Is |x| < 0.5? - cmp.ge p7,p0 = rExp, rBigexp // Is |x| >= 2^52? - cmp.lt p10,p0 = rExp, rExpHalf // Is |x| < 0.5? +// Float the truncated integer +{ .mfi + nop.m 999 +(p9) fcvt.xf ROUND_FLOAT_TRUNC_f8 = ROUND_TRUNC_f8 + nop.i 999 ;; } -;; -// We must correct result if |x| < 0.5, or |x| >= 2^52 -.pred.rel "mutex",p6,p7 +// Float the rounded integer to get preliminary result { .mfi - nop.m 0 -(p6) fmerge.s f8 = fNormX, f0 // If |x| < 0.5, result sgn(x)*0 - nop.i 0 + nop.m 999 +(p9) fcvt.xf ROUND_FLOAT_RINT_f8 = ROUND_RINT_f8 + nop.i 999 ;; +} + +// If x<0 and the difference of the truncated input minus the input is 0.5 +// then result = truncated input - 1.0 +// Else if x>0 and the difference of the input minus truncated input is 0.5 +// then result = truncated input + 1.0 +// Else +// result = rounded input +// Endif +{ .mfi + nop.m 999 +(p6) fsub.s1 ROUND_REMAINDER = ROUND_FLOAT_TRUNC_f8, ROUND_NORM_f8 + nop.i 999 } -{ .mfb -(p7) cmp.eq p10,p0 = r0, r0 // Also turn on p10 if |x| >= 2^52 -(p7) fma.d.s0 f8 = fNormX, f1, f0 // If |x| >= 2^52, result x -(p10) br.ret.spnt b0 // Exit |x| < 0.5 or |x| >= 2^52 + +{ .mfi + nop.m 999 +(p7) fsub.s1 ROUND_REMAINDER = ROUND_NORM_f8, ROUND_FLOAT_TRUNC_f8 + nop.i 999 ;; } -;; -// Here if 0.5 <= |x| < 2^52 +// Assume preliminary result is rounded integer { .mfi - nop.m 0 -(p9) fms.s1 fRem = fNormX, f1, f8 // Get remainder = x - trunc(x) - nop.i 0 + nop.m 999 +(p9) fnorm.d.s0 f8 = ROUND_FLOAT_RINT_f8 + nop.i 999 } + +// If x<0, test if result=0 { .mfi - nop.m 0 -(p8) fms.s1 fRem = f8, f1, fNormX // Get remainder = trunc(x) - x - nop.i 0 + nop.m 999 +(p6) fcmp.eq.unc p10,p0 = ROUND_FLOAT_RINT_f8,f0 + nop.i 999 ;; } -;; +// If x<0 and result=0, set result=-0 { .mfi - nop.m 0 - fcmp.ge.s1 p9,p0 = fRem, fHalf // Test |rem| >= 0.5 - nop.i 0 + nop.m 999 +(p10) fmerge.ns f8 = f1,f8 + nop.i 999 } -;; - -// If x < 0 and remainder <= -0.5, then subtract 1 from result -// If x > 0 and remainder >= +0.5, then add 1 to result -{ .mfb - nop.m 0 -(p9) fma.d.s0 f8 = f8, f1, fInc - br.ret.sptk b0 + +// If x<0, test if remainder=0.5 +{ .mfi + nop.m 999 +(p6) fcmp.eq.unc p6,p0 = ROUND_REMAINDER, ROUND_HALF + nop.i 999 ;; } -;; - - -ROUND_SPECIAL: -// Here if x natval, nan, inf -{ .mfb - nop.m 0 - fma.d.s0 f8 = f8, f1, f0 - br.ret.sptk b0 + +// If x>0, test if remainder=0.5 +{ .mfi + nop.m 999 +(p7) fcmp.eq.unc p7,p0 = ROUND_REMAINDER, ROUND_HALF + nop.i 999 ;; } -;; -ROUND_UNORM: -// Here if x unorm +// If x<0 and remainder=0.5, result=truncated-1.0 +// If x>0 and remainder=0.5, result=truncated+1.0 +// Exit +.pred.rel "mutex",p6,p7 { .mfi - getf.exp rSignexp = fNormX // Get signexp, recompute if unorm - fcmp.eq.s0 p7,p0 = f8, f0 // Dummy op to set denormal flag - nop.i 0 + nop.m 999 +(p6) fsub.d.s0 f8 = ROUND_FLOAT_TRUNC_f8,f1 + nop.i 999 } + { .mfb - nop.m 0 - fcvt.fx.trunc.s1 fXtruncInt = fNormX // Convert to int in significand - br.cond.sptk ROUND_COMMON // Return to main path + nop.m 999 +(p7) fadd.d.s0 f8 = ROUND_FLOAT_TRUNC_f8,f1 + br.ret.sptk b0 ;; } -;; -GLOBAL_LIBM_END(round) +.endp round +ASM_SIZE_DIRECTIVE(round) |