Sender:	ghh AT mail DOT mtk DOT nao DOT ac DOT jp
Message-ID:	<38BB81DB.B4CF937B@nao.ac.jp>
Date:	Tue, 29 Feb 2000 17:22:51 +0900
From:	Gerhard Heinzel <gerhard DOT heinzel AT nao DOT ac DOT jp>
Organization:	National Astronomical Observatory, Mitaka, Tokyo, Japan
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MIME-Version:	1.0
To:	pgcc AT delorie DOT com
Subject:	inline optimizer bug
Reply-To:	pgcc AT delorie DOT com

I use
pgcc-2.95.2 19991024 (release)

The attached code is compiled wrongly with -O3
I believe the problem is in the line marked with
asterisks, but I do not understand enough assembler
to look into it myself.

RIGHT:
ghh AT ghhpc:/home/ghh > gcc  -o err0 err.c 
ghh AT ghhpc:/home/ghh > err0
  3.71849 5.57773 4.71849 5.57773
  -6.77209 16.253 -2.05361 21.8307 2.32759 3.49138 -2.05361 21.8307

WRONG:
ghh AT ghhpc:/home/ghh > gcc -Wall -O3 -o err1 err.c
ghh AT ghhpc:/home/ghh > err1
  3.71849 5.57773 4.71849 5.57773
  3.16767 6.98277 7.88616 12.5605 2.32759 3.49138 7.88616 12.5605


-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 Gerhard Heinzel                   e-mail: gerhard DOT heinzel AT nao DOT ac DOT jp
 Space-Time Astronomy Section, 
 National Astronomical Observatory, 2-21-1 Ohsawa, Mitaka,
 Tokyo 181-8588, Japan,    FAX: 81+422-34-3793,  Tel. 81+422-34-3618
 http://tamago.mtk.nao.ac.jp/   
http://users.cybercity.dk/~cis6614/Lucia 
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

#include <stdio.h>

struct complex_t
  {
    double re, im;
  };
typedef struct complex_t mycomplex;


static inline mycomplex
zadd (mycomplex z1, mycomplex z2)
{
  mycomplex z;

  z.re = z1.re + z2.re;
  z.im = z1.im + z2.im;

  return z;
}

static inline mycomplex
zmlt (mycomplex z1, mycomplex z2)
{
  mycomplex z;

  z.re = z1.re * z2.re - z1.im * z2.im;
  z.im = z1.re * z2.im + z1.im * z2.re;

  return z;
}

int
main (void)
{
  double polef = 0.429629;
  double poleq = 0.625951;
  mycomplex x, x1, s, y, z1, z2;

  s.re = 1;
  s.im = 1.5;
  x.re = 1.;
  x.im = 0.;

  x1.re = 1.;
  x1.im = 0.;
  y = s;
  y.re /= (polef * poleq);
  y.im /= (polef * poleq);
  z1 = zadd (x1, y);
  x1 = z1;
  printf ("  %g %g %g %g\n", y.re, y.im, x1.re, x1.im);
  y = s;
  y.re /= (polef);
  y.im /= (polef);
  z1 = zmlt (y, y);
  z2 = zadd (x1, z1);
  x1 = z2;
  printf ("  %g %g %g %g %g %g %g %g\n", 
   z1.re, z1.im, z2.re, z2.im, y.re, y.im, x1.re, x1.im);
  return 0;
}

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