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Diffstat (limited to 'sysdeps/ia64/fpu/s_libm_scalbn.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_libm_scalbn.S | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/sysdeps/ia64/fpu/s_libm_scalbn.S b/sysdeps/ia64/fpu/s_libm_scalbn.S new file mode 100644 index 0000000000..eaccb7de7a --- /dev/null +++ b/sysdeps/ia64/fpu/s_libm_scalbn.S @@ -0,0 +1,452 @@ +.file "libm_scalbn.s" + + +// Copyright (c) 2000 - 2003, Intel Corporation +// All rights reserved. +// +// 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 +// 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. +// +// * 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 +// 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://www.intel.com/software/products/opensource/libraries/num.htm. +// +// History +//============================================================== +// 02/02/00 Initial version +// 01/26/01 Scalbn completely reworked and now standalone version +// 01/04/02 Added handling for int 32 or 64 bits +// 05/20/02 Cleaned up namespace and sf0 syntax +// 02/10/03 Reordered header: .section, .global, .proc, .align +// 08/04/03 Improved performance +// +// API +//============================================================== +// double __libm_scalbn (double x, int n, int int_type) +// input floating point f8 and int n (r33), int int_type (r34) +// output floating point f8 +// +// int_type = 0 if int is 32 bits +// int_type = 1 if int is 64 bits +// +// Returns x* 2**n using an fma and detects overflow +// and underflow. +// +// +// Strategy: +// Compute biased exponent of result exp_Result = N + exp_X +// Break into ranges: +// exp_Result > 0x103fe -> Certain overflow +// exp_Result = 0x103fe -> Possible overflow +// 0x0fc01 <= exp_Result < 0x103fe -> No over/underflow (main path) +// 0x0fc01 - 52 <= exp_Result < 0x0fc01 -> Possible underflow +// exp_Result < 0x0fc01 - 52 -> Certain underflow + +FR_Big = f6 +FR_NBig = f7 +FR_Floating_X = f8 +FR_Result = f8 +FR_Result2 = f9 +FR_Result3 = f10 +FR_Norm_X = f11 +FR_Two_N = f12 + +GR_neg_ov_limit= r14 +GR_N_Biased = r15 +GR_Big = r16 +GR_NBig = r17 +GR_exp_Result = r18 +GR_pos_ov_limit= r19 +GR_Bias = r20 +GR_N_as_int = r21 +GR_signexp_X = r22 +GR_exp_X = r23 +GR_exp_mask = r24 +GR_max_exp = r25 +GR_min_exp = r26 +GR_min_den_exp = r27 + +GR_SAVE_B0 = r32 +GR_SAVE_GP = r33 +GR_SAVE_PFS = r34 +GR_Parameter_X = r35 +GR_Parameter_Y = r36 +GR_Parameter_RESULT = r37 +GR_Tag = r38 + +.section .text +GLOBAL_LIBM_ENTRY(__libm_scalbn) + +// +// Is x NAN, INF, ZERO, +-? +// Build the exponent Bias +// +{ .mfi + getf.exp GR_signexp_X = FR_Floating_X // Get signexp of x + fclass.m p6,p0 = FR_Floating_X, 0xe7 // @snan | @qnan | @inf | @zero + mov GR_Bias = 0x0ffff +} +// +// Normalize x +// Is integer type 32 bits? +// +{ .mfi + mov GR_Big = 35000 // If N this big then certain overflow + fnorm.s1 FR_Norm_X = FR_Floating_X + cmp.eq p8,p9 = r34,r0 +} +;; + +// Sign extend N if int is 32 bits +{ .mfi +(p9) mov GR_N_as_int = r33 // Copy N if int is 64 bits + fclass.m p9,p0 = FR_Floating_X, 0x0b // Test for x=unorm +(p8) sxt4 GR_N_as_int = r33 // Sign extend N if int is 32 bits +} +{ .mfi + mov GR_NBig = -35000 // If N this small then certain underflow + nop.f 0 + mov GR_max_exp = 0x103fe // Exponent of maximum double +} +;; + +// Create biased exponent for 2**N +{ .mfi + add GR_N_Biased = GR_Bias,GR_N_as_int + nop.f 0 + cmp.ge p7, p0 = GR_N_as_int, GR_Big // Certain overflow? +} +{ .mib + cmp.le p8, p0 = GR_N_as_int, GR_NBig // Certain underflow? + mov GR_min_exp = 0x0fc01 // Exponent of minimum double +(p9) br.cond.spnt SCALBN_UNORM // Branch if x=unorm +} +;; + +SCALBN_COMMON: +// Main path continues. Also return here from x=unorm path. +// Create 2**N +.pred.rel "mutex",p7,p8 +{ .mfi + setf.exp FR_Two_N = GR_N_Biased + nop.f 0 +(p7) mov GR_N_as_int = GR_Big // Limit max N +} +{ .mfi +(p8) mov GR_N_as_int = GR_NBig // Limit min N + nop.f 0 +(p8) cmp.eq p7,p0 = r0,r0 // Set p7 if |N| big +} +;; + +// +// Create biased exponent for 2**N for N big +// Is N zero? +// +{ .mfi +(p7) add GR_N_Biased = GR_Bias,GR_N_as_int + nop.f 0 + cmp.eq.or p6,p0 = r33,r0 +} +{ .mfi + mov GR_pos_ov_limit = 0x103ff // Exponent for positive overflow + nop.f 0 + mov GR_exp_mask = 0x1ffff // Exponent mask +} +;; + +// +// Create 2**N for N big +// Return x when N = 0 or X = Nan, Inf, Zero +// +{ .mfi +(p7) setf.exp FR_Two_N = GR_N_Biased + nop.f 0 + mov GR_min_den_exp = 0x0fc01 - 52 // Exponent of min denorm dble +} +{ .mfb + and GR_exp_X = GR_exp_mask, GR_signexp_X +(p6) fma.d.s0 FR_Result = FR_Floating_X, f1, f0 +(p6) br.ret.spnt b0 +} +;; + +// +// Raise Denormal operand flag with compare +// Compute biased result exponent +// +{ .mfi + add GR_exp_Result = GR_exp_X, GR_N_as_int + fcmp.ge.s0 p0,p11 = FR_Floating_X,f0 + mov GR_neg_ov_limit = 0x303ff // Exponent for negative overflow +} +;; + +// +// Do final operation +// +{ .mfi + cmp.lt p7,p6 = GR_exp_Result, GR_max_exp // Test no overflow + fma.d.s0 FR_Result = FR_Two_N,FR_Norm_X,f0 + cmp.lt p9,p0 = GR_exp_Result, GR_min_den_exp // Test sure underflow +} +{ .mfb + nop.m 0 + nop.f 0 +(p9) br.cond.spnt SCALBN_UNDERFLOW // Branch if certain underflow +} +;; + +{ .mib +(p6) cmp.gt.unc p6,p8 = GR_exp_Result, GR_max_exp // Test sure overflow +(p7) cmp.ge.unc p7,p9 = GR_exp_Result, GR_min_exp // Test no over/underflow +(p7) br.ret.sptk b0 // Return from main path +} +;; + +{ .bbb +(p6) br.cond.spnt SCALBN_OVERFLOW // Branch if certain overflow +(p8) br.cond.spnt SCALBN_POSSIBLE_OVERFLOW // Branch if possible overflow +(p9) br.cond.spnt SCALBN_POSSIBLE_UNDERFLOW // Branch if possible underflow +} +;; + +// Here if possible underflow. +// Resulting exponent: 0x0fc01-52 <= exp_Result < 0x0fc01 +SCALBN_POSSIBLE_UNDERFLOW: +// +// Here if possible overflow. +// Resulting exponent: 0x103fe = exp_Result +SCALBN_POSSIBLE_OVERFLOW: + +// Set up necessary status fields +// +// S0 user supplied status +// S2 user supplied status + WRE + TD (Overflows) +// S3 user supplied status + FZ + TD (Underflows) +// +{ .mfi + nop.m 0 + fsetc.s3 0x7F,0x41 + nop.i 0 +} +{ .mfi + nop.m 0 + fsetc.s2 0x7F,0x42 + nop.i 0 +} +;; + +// +// Do final operation with s2 and s3 +// +{ .mfi + setf.exp FR_NBig = GR_neg_ov_limit + fma.d.s3 FR_Result3 = FR_Two_N,FR_Norm_X,f0 + nop.i 0 +} +{ .mfi + setf.exp FR_Big = GR_pos_ov_limit + fma.d.s2 FR_Result2 = FR_Two_N,FR_Norm_X,f0 + nop.i 0 +} +;; + +// Check for overflow or underflow. +// Restore s3 +// Restore s2 +// +{ .mfi + nop.m 0 + fsetc.s3 0x7F,0x40 + nop.i 0 +} +{ .mfi + nop.m 0 + fsetc.s2 0x7F,0x40 + nop.i 0 +} +;; + +// +// Is the result zero? +// +{ .mfi + nop.m 0 + fclass.m p6, p0 = FR_Result3, 0x007 + nop.i 0 +} +{ .mfi + nop.m 0 + fcmp.ge.s1 p7, p8 = FR_Result2 , FR_Big + nop.i 0 +} +;; + +// +// Detect masked underflow - Tiny + Inexact Only +// +{ .mfi + nop.m 0 +(p6) fcmp.neq.unc.s1 p6, p0 = FR_Result , FR_Result2 + nop.i 0 +} +;; + +// +// Is result bigger the allowed range? +// Branch out for underflow +// +{ .mfb + nop.m 0 +(p8) fcmp.le.unc.s1 p9, p10 = FR_Result2 , FR_NBig +(p6) br.cond.spnt SCALBN_UNDERFLOW +} +;; + +// +// Branch out for overflow +// +{ .bbb +(p7) br.cond.spnt SCALBN_OVERFLOW +(p9) br.cond.spnt SCALBN_OVERFLOW + br.ret.sptk b0 // Return from main path. +} +;; + +// Here if result overflows +SCALBN_OVERFLOW: +{ .mib + alloc r32=ar.pfs,3,0,4,0 + addl GR_Tag = 176, r0 // Set error tag for overflow + br.cond.sptk __libm_error_region // Call error support for overflow +} +;; + +// Here if result underflows +SCALBN_UNDERFLOW: +{ .mib + alloc r32=ar.pfs,3,0,4,0 + addl GR_Tag = 177, r0 // Set error tag for underflow + br.cond.sptk __libm_error_region // Call error support for underflow +} +;; + +// Here if x=unorm +SCALBN_UNORM: +{ .mib + getf.exp GR_signexp_X = FR_Norm_X // Get signexp of normalized x + nop.i 0 + br.cond.sptk SCALBN_COMMON // Return to main path +} +;; + + +GLOBAL_LIBM_END(__libm_scalbn) +LOCAL_LIBM_ENTRY(__libm_error_region) + +// +// Get stack address of N +// +.prologue +{ .mfi + add GR_Parameter_Y=-32,sp + nop.f 0 +.save ar.pfs,GR_SAVE_PFS + mov GR_SAVE_PFS=ar.pfs +} +// +// Adjust sp +// +{ .mfi +.fframe 64 + add sp=-64,sp + nop.f 0 + mov GR_SAVE_GP=gp +};; + +// +// Store N on stack in correct position +// Locate the address of x on stack +// +{ .mmi + st8 [GR_Parameter_Y] = GR_N_as_int,16 + add GR_Parameter_X = 16,sp +.save b0, GR_SAVE_B0 + mov GR_SAVE_B0=b0 +};; + +// +// Store x on the stack. +// Get address for result on stack. +// +.body +{ .mib + stfd [GR_Parameter_X] = FR_Norm_X + add GR_Parameter_RESULT = 0,GR_Parameter_Y + nop.b 0 +} +{ .mib + stfd [GR_Parameter_Y] = FR_Result + add GR_Parameter_Y = -16,GR_Parameter_Y + br.call.sptk b0=__libm_error_support# +};; + +// +// Get location of result on stack +// +{ .mmi + add GR_Parameter_RESULT = 48,sp + nop.m 0 + nop.i 0 +};; + +// +// Get the new result +// +{ .mmi + ldfd FR_Result = [GR_Parameter_RESULT] +.restore sp + add sp = 64,sp + mov b0 = GR_SAVE_B0 +};; + +// +// Restore gp, ar.pfs and return +// +{ .mib + mov gp = GR_SAVE_GP + mov ar.pfs = GR_SAVE_PFS + br.ret.sptk b0 +};; + +LOCAL_LIBM_END(__libm_error_region) + +.type __libm_error_support#,@function +.global __libm_error_support# |