c/3221: simplify_gen_subreg ICE for mips compiler

c/3221: simplify_gen_subreg ICE for mips compiler

[Anthony Green]

>Number:         3221
>Category:       c
>Synopsis:       simplify_gen_subreg ICE for mips compiler
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          ice-on-legal-code
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 18 03:26:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Anthony Green
>Release:        3.1 20010617 (experimental)
>Organization:
>Environment:
System: Linux fencer.cygnus.com 2.2.12-20smp #1 SMP Mon Sep 27 10:34:45 EDT 1999 i686 unknown
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: mips-mips-elf
configured with: /horton/green/gcj-test/2001-06-17-18.45.14/gcc/gcc/configure --prefix=/horton/green/gcj-test/2001-06-17-18.45.14/mips-elf/install --program-prefix=mips-elf- --target=mips-elf --with-gnu-as --with-gnu-ld
>Description:
	The mips-elf compiler from the trunk can't build a -mips3 newlib.  We get an ICE in simplify_gen_subreg for __ieee754_hypotf.
>How-To-Repeat:
Compile the following nonsensical reduced case, e.c:

typedef union
{
  float value;
  unsigned int word;
} ieee_float_shape_type;

float __ieee754_sqrtf(float x);
float __ieee754_hypotf(float x, float y)
{
        float t1;

        ieee_float_shape_type sf_u; 
        sf_u.word = 0 ;
        t1 = sf_u.value; 

        return __ieee754_sqrtf(t1);
}

with 

  ./cc1 -mfp64 -mgp64 -mips3 -O2 e.c 	

It will result in...

e.c: In function `__ieee754_hypotf':
e.c:17: Internal compiler error in simplify_gen_subreg, at simplify-rtx.c:2457
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL: http://www.gnu.org/software/gcc/bugs.html > for instructions.

>Fix:
	
>Release-Note:
>Audit-Trail:
>Unformatted: