An x86 -fpic and -fomit-frame-pointer bug

[H.J. Lu]

>  > 
>  > It shows you are the only one who ever tried my testcase :-). Here
>  > is the complete testcase.
> 
> Thanks. BUT, egcs-1.0.3a is buggy, too:
> 
> Interestingly, gcc-2.8.1 is OK:
> 
> $ LD_RUN_PATH=/tools/gnu/lib/gcc-lib/i586-linux/2.8.1 gmake CC=/tools/gnu/packages/gcs/2.8.1/bin/gcc 
> /tools/gnu/packages/gcs/2.8.1/bin/gcc -S -O2 -fno-exceptions main.cc
> /tools/gnu/packages/gcs/2.8.1/bin/gcc -S -fomit-frame-pointer -O3 -fpic -fno-exceptions  cexp.cc
> /tools/gnu/packages/gcs/2.8.1/bin/gcc -o main main.s cexp.s -lstdc++
> for f in main; do echo "Running: $f"; $f; \
>   if [ $? != 0 ]; then echo Failed; fi; done
> Running: main
> 22.1672, 1.04274
> 

gcc-2.8.1 is buggy too. Try this cexp.cc on gcc-2.8.1.

BTW, it should be fixed in egcs 1.1. I have proposed 2 solutions and
sent in a kludge to disable -fomit-frame-pointer for PIC.


H.J.
---cexp.cc---
#include "cexp.h"

__inline  double exp (double __x);
__inline  double
exp (double __x)
{
  register double __value, __exponent;
#if 1
#if 1
  __asm __volatile__
    ("fldl2e			# e^x = 2^(x * log2(e))\n\t"
     "fmul	%%st(1)		# x * log2(e)\n\t"
     "fstl	%%st(1)\n\t"
     "frndint			# int(x * log2(e))\n\t"
     "fxch\n\t"
     "fsub	%%st(1)		# fract(x * log2(e))\n\t"
     "f2xm1			# 2^(fract(x * log2(e))) - 1\n\t"
     : "=t" (__value), "=u" (__exponent) : "0" (__x));
#endif
  __value += 1.0;
  __asm __volatile__
    ("fscale"
     : "=t" (__value) : "0" (__value), "u" (__exponent));

  return __value;
#else
  return __x;
#endif
}
__inline  double sin (double __x);
__inline  double
sin (double __x)
{
#if 1
  register double __value;
  __asm __volatile__
    ("fsin"
     : "=t" (__value) : "0" (__x));
  return __value;
#else
  return __x;
#endif
}
__inline  double cos (double __x);
__inline  double
cos (double __x)
{
#if 1
  register double __value;
  __asm __volatile__
    ("fcos"
     : "=t" (__value): "0" (__x));
  return __value;
#else
  return __x;
#endif
}
template <class FLOAT> complex<FLOAT>
exp (const complex<FLOAT>& x)
{
  return polar (FLOAT (exp (x.real ())), x.imag ());
}
template c exp (ccr);