[Bug math/14472] Inaccurate y1f function on x86_32 and x86_64

["liubov.dmitrieva at gmail dot com" <sourceware-bugzilla at sourceware dot org>]

http://sourceware.org/bugzilla/show_bug.cgi?id=14472

--- Comment #2 from Liubov Dmitrieva <liubov.dmitrieva at gmail dot com> 2012-08-16 08:23:12 UTC ---
>> represent the test argument using a hex float value

Updated test:

#include <stdio.h>
#include <math.h>
#include <fenv.h>

extern float y1f(float);
extern double y1(double);

int main() {
    float a,r1;
    double r2;

    a=0x1.598178p5;    //argument

    fesetround(FE_TONEAREST);

    r1 = y1f(a);  //actual result
    r2 = y1(a);   //actual result 2

    printf("inputs: a = %.6a\n", a);
    printf("actual    = %.6a\n", r1);
    printf("expected  = %.6a\n", r2);
    printf("error     = %f ulp\n", fabs(r1 - r2) * exp2(23.0-logbf(r1)));
    return 0;
}

Result x86:
inputs: a = 0x1.598178p+5
actual    = 0x1.e76056p-24
expected  = 0x1.e72698p-24
error     = 7390.926985 ulp

Result x86_64:
inputs: a = 0x1.598178p+5
actual    = 0x1.e7497ap-24
expected  = 0x1.e72698p-24
error     = 4464.927009 ulp

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