diff options
Diffstat (limited to 'sysdeps/ia64/fpu/s_trunc.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_trunc.S | 207 |
1 files changed, 86 insertions, 121 deletions
diff --git a/sysdeps/ia64/fpu/s_trunc.S b/sysdeps/ia64/fpu/s_trunc.S index 0be9120..b9ad03b 100644 --- a/sysdeps/ia64/fpu/s_trunc.S +++ b/sysdeps/ia64/fpu/s_trunc.S @@ -1,11 +1,10 @@ .file "trunc.s" -// Copyright (C) 2000, 2001, Intel Corporation + +// Copyright (c) 2000 - 2003, Intel Corporation // All rights reserved. -// -// Contributed 7/7/2000 by John Harrison, Cristina Iordache, Ted Kubaska, -// Bob Norin, Shane Story, and Ping Tak Peter Tang of the -// Computational Software Lab, Intel Corporation. +// +// Contributed 2000 by the Intel Numerics Group, Intel Corporation // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are @@ -21,33 +20,28 @@ // * 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://developer.intel.com/opensource. +// problem reports or change requests be submitted to it directly at +// http://www.intel.com/software/products/opensource/libraries/num.htm. // -.align 32 -.global trunc# - -.section .text -.proc trunc# -.align 32 - // History //============================================================== -// 7/7/00: Created +// 07/07/00 Created +// 05/20/02 Cleaned up namespace and sf0 syntax +// 01/20/03 Improved performance and reduced code size //============================================================== // API @@ -55,25 +49,28 @@ // double trunc(double x) //============================================================== -#include "libm_support.h" +// general input registers: +// r14 - r18 -// general input registers: -TRUNC_GR_FFFF = r14 -TRUNC_GR_signexp = r15 -TRUNC_GR_exponent = r16 -TRUNC_GR_expmask = r17 -TRUNC_GR_bigexp = r18 +rExpBias = r14 +rSignexp = r15 +rExp = r16 +rExpMask = r17 +rBigexp = r18 // floating-point registers: -// f8, f9, f11, f12 +// f8 - f10 + +fXtruncInt = f9 +fNormX = f10 -// predicate registers used: -// p6, p7, p8, p9, p10, p11 +// predicate registers used: +// p6, p7 // Overview of operation //============================================================== // double trunc(double x) -// Return an integer value (represented as a double) less than or +// Return an integer value (represented as a double) less than or // equal to x in magnitude. // This is x rounded toward zero to an integral value. //============================================================== @@ -97,105 +94,73 @@ TRUNC_GR_bigexp = r18 // If we multiply by 2^23, we no longer have a fractional part // So input is an integer value already. -trunc: +.section .text +GLOBAL_LIBM_ENTRY(trunc) { .mfi - getf.exp TRUNC_GR_signexp = f8 - fcvt.fx.trunc.s1 f9 = f8 - addl TRUNC_GR_bigexp = 0x10033, r0 + 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 } { .mfi - mov TRUNC_GR_FFFF = 0x0FFFF - fnorm.d f11 = f8 - mov TRUNC_GR_expmask = 0x1FFFF -};; -// get the exponent of x -// convert x to integer in signficand of f9 -// Normalize x - this will raise invalid on SNaNs, the -// denormal operand flag - and possibly a spurious U flag -// get exponent only mask (will exclude sign bit) + mov rExpBias = 0x0FFFF // Form exponent bias + fnorm.s1 fNormX = f8 // Normalize input + mov rExpMask = 0x1FFFF // Form exponent mask +} +;; { .mfi nop.m 0 - fclass.m p7,p8 = f8, 0x0b + fclass.m p7,p0 = f8, 0x0b // Test x unorm nop.i 0 } -{ .mfi - nop.m 0 - fcmp.eq.unc.s1 p9,p0 = f8,f0 - nop.i 0 -};; -// fclass to set p7 if unnorm -{ .mmi - and TRUNC_GR_exponent = TRUNC_GR_signexp, TRUNC_GR_expmask ;; -(p8) cmp.ge.unc p10,p11 = TRUNC_GR_exponent, TRUNC_GR_bigexp -(p8) cmp.ne.unc p6,p0 = TRUNC_GR_exponent, TRUNC_GR_signexp -};; -// Get the exponent of x -// Test if exponent such that result already an integer -// Test if x < 0 -{ .mmi -(p9) cmp.eq.andcm p10,p11 = r0, r0 -(p6) cmp.lt.unc p6,p0 = TRUNC_GR_exponent, TRUNC_GR_FFFF - nop.i 0 -};; -// If -1 < x < 0, set p6, turn off p10 and p11, and set result to -0.0 -{ .mfb -(p6) cmp.eq.andcm p10,p11 = r0, r0 -(p6) fmerge.s f8 = f8, f0 - nop.b 0 -};; -// If not a unnorm, set p10 if x already is a big int, nan, or inf? -// If not a unnorm, set p10 if x already is a big int, nan, or inf? -.pred.rel "mutex",p10,p11 +;; + { .mfb nop.m 0 -(p11) fcvt.xf f8 = f9 - nop.b 0 + fclass.m p6,p0 = f8, 0x1e3 // Test x natval, nan, inf +(p7) br.cond.spnt TRUNC_UNORM // Branch if x unorm } +;; + +TRUNC_COMMON: +// Return here from TRUNC_UNORM { .mfb + and rExp = rSignexp, rExpMask // Get biased exponent +(p6) fma.d.s0 f8 = f8, f1, f0 // Result if x natval, nan, inf +(p6) br.ret.spnt b0 // Exit if x natval, nan, inf +} +;; + +{ .mfi + cmp.lt p6,p0 = rExp, rExpBias // Is |x| < 1? + fcvt.xf f8 = fXtruncInt // Result, assume 1 <= |x| < 2^52 + cmp.ge p7,p0 = rExp, rBigexp // Is |x| >= 2^52? +} +;; + +// We must correct result if |x| < 1, or |x| >= 2^52 +.pred.rel "mutex",p6,p7 +{ .mfi nop.m 0 -(p10) fma.d.s1 f8 = f11,f1,f0 -(p8) br.ret.sptk b0 -};; -// If not a unnorm and not an big int, nan,or +/-inf convert signficand -// back to f8. -// If not a unorm and a big int, nan, or +/-inf, return fnorm'd x -// If not a unorm, Return -// If unnorm, get the exponent again - perhaps it wasn't a denorm. -{ .mfb -(p7) getf.exp TRUNC_GR_signexp = f11 -(p7) fcvt.fx.trunc.s1 f12 = f11 - nop.b 0 -};; -{ .mfb - and TRUNC_GR_exponent = TRUNC_GR_signexp, TRUNC_GR_expmask - fcmp.lt.unc.s1 p9,p0 = f8,f0 - nop.b 0 -};; -{ .mfb - cmp.ge.unc p10,p11 = TRUNC_GR_exponent, TRUNC_GR_bigexp - nop.f 0 - nop.b 0 -};; -// If a unnorm, check to see if value is already a big int. +(p6) fmerge.s f8 = fNormX, f0 // If |x| < 1, result sgn(x)*0 + nop.i 0 +} { .mfb - nop.m 0 -(p11) fcvt.xf f8 = f12 - nop.b 0 + nop.m 0 +(p7) fma.d.s0 f8 = fNormX, f1, f0 // If |x| >= 2^52, result x + br.ret.sptk b0 // Exit main path } -{ .mfi - nop.m 0 -(p10) fma.d.s1 f8 = f11,f1,f0 - nop.i 0 -};; +;; + + +TRUNC_UNORM: +// Here if x unorm { .mfb - nop.m 0 -(p9) fmerge.ns f8 = f1,f8 - br.ret.sptk b0 -};; -// If so return it. Otherwise, return (fcvt.xf(fcvt.fx.trunc(x))) -// Make sure the result is negative if it should be - that is -// negative(denormal) -> -0. -.endp trunc -ASM_SIZE_DIRECTIVE(trunc) + getf.exp rSignexp = fNormX // Get signexp, recompute if unorm + fcmp.eq.s0 p7,p0 = f8, f0 // Dummy op to set denormal flag + br.cond.sptk TRUNC_COMMON // Return to main path +} +;; + +GLOBAL_LIBM_END(trunc) |