[commit-cp] [bugs #11058] ARM double to ascii conversion issue

[anonymous]

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 of the project: classpath.

/**************************************************************************/
[bugs #11058] Latest Modifications:

Changes by: Anonymous user
Date:  
                lun 22.11.2004 at 08:40

------------------ Additional Follow-up Comments ----------------------------
Tested your class, and I've added some other tests too.
/ Below is Java File /
import java.io.*;
 
public class Cos {
 
   public static double div(double a, double b){
    return a/b;
   }
 
   public static void main(String[] args){
       double a = Math.cos(Math.PI);
       double b = -1.0;
       System.out.println("a equals b:"+(a == b));
       System.out.println("a:"+a);
       System.out.println("b:"+b);       
       a = 1.002;
       b = 0.;
       System.out.println("a div b:" + div(a,b));
       System.out.println("a:"+a);
       System.out.println("b:"+b);       
    a = 8.8888888E21;
       b = 5.5555555E-21;
       System.out.println("a:"+a);
       System.out.println("b:"+b);
 
   }
}

/ And this is the output /
a equals b:true
a:-1.0
b:-1.0
a div b:Infinity
a:2.002:958353678385
b:0.0
a:0.0000000000026E21
b:Q.0E-21






/**************************************************************************/
[bugs #11058] Full Item Snapshot:

URL: <http://savannah.gnu.org/bugs/?func=detailitem&item_id=11058>
Project: classpath
Submitted by: 0
On: ven 19.11.2004 at 12:56

Category:  classpath
Severity:  5 - Average
Resolution:  None
Privacy:  Public
Assigned to:  None
Status:  Open
Platform Version:  None


Summary:  ARM double to ascii conversion issue

Original Submission:  Hi,

  I've cross compiled CLASSPATH on an S3C2410 ARM920 architecture. I've also 
compiled SableVM on it.
When I run this code :
    float a = 1.5f;
    float b = 26.524f;
    float c = 1.11E11f;
    float d = a + b;
    int   e = (int)d;
  
    System.Out.println("a is "+a);
    System.Out.println("b is "+b);
    System.Out.println("d is "+d);
    System.Out.println("e is "+e);

I get wrong result for float (and double, I've tried them too) output (the 
output is totally garbaged), but the number show as e is correct. 
I think the problem seem to be in _dtoa function in fdlibm.

ARM are very strict on memory alignment, and is little endian.

PS: The same code works on x86.

Output is (This is the input => a=1.5f,b=26.524f,c=1.11E11f):
----------
float test
----------
a=1.000007
b=37.63494
c=1.1100000256E11
(int)a =1
(int)b =26
(int)c =2147483647
a+b=39.034943
a+c=1.1100000256E11
a-b=-36.034943
a-c=-1.1100000256E11
(int)(a+b)=28
(int)(a+c)=2147483647
(int)(a-b)=-25
(int)(a-c)=-2147483648
a*b=4:.89693;
a*c=1.66500007936E11
a/b=0.02
a/c=28.7935:8
(int)(a*b)=39
(int)(a*c)=2147483647
(int)(a/b)=0
(int)(a/c)=17



Follow-up Comments
------------------


-------------------------------------------------------
Date: lun 22.11.2004 at 08:40       By: 0 <None>
Tested your class, and I've added some other tests too.
/ Below is Java File /
import java.io.*;
 
public class Cos {
 
   public static double div(double a, double b){
    return a/b;
   }
 
   public static void main(String[] args){
       double a = Math.cos(Math.PI);
       double b = -1.0;
       System.out.println("a equals b:"+(a == b));
       System.out.println("a:"+a);
       System.out.println("b:"+b);       
       a = 1.002;
       b = 0.;
       System.out.println("a div b:" + div(a,b));
       System.out.println("a:"+a);
       System.out.println("b:"+b);       
    a = 8.8888888E21;
       b = 5.5555555E-21;
       System.out.println("a:"+a);
       System.out.println("b:"+b);
 
   }
}

/ And this is the output /
a equals b:true
a:-1.0
b:-1.0
a div b:Infinity
a:2.002:958353678385
b:0.0
a:0.0000000000026E21
b:Q.0E-21

-------------------------------------------------------
Date: lun 22.11.2004 at 04:18       By: Sven de Marothy <smarothy>
I'm not entirely sure if this is a general fdlibm problem, or specific to dtoa. 
Could you test this? 

I've attached a little test-case which might be an indicator,  checking the 
output of a fdlibm function with the expected value.

-------------------------------------------------------
Date: lun 22.11.2004 at 03:57       By: Michael Koch <mkoch>
This was originally reported to http://sablevm.org/bugs/74

-------------------------------------------------------
Date: ven 19.11.2004 at 17:53       By: Sven de Marothy <smarothy>
Unfortunately, most of us don't have an ARM machine to test this on. 

However, looking at the fdlibm code, there's #ifdefs for ARM in ieeefp.h, and 
some more in atoi.c (Pack_32?) so it could be a build issue. I'd try playing 
around with the #ifdefs.

If you find something, please post it here and let us know!







File Attachments
-------------------

-------------------------------------------------------
Date: lun 22.11.2004 at 04:18  Name: Cos.java  Size: 278B   By: smarothy
Test
http://savannah.gnu.org/bugs/download.php?item_id=11058&amp;item_file_id=1902






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