patch that caused regression PR middle-end/8808

[Janis Johnson]

The regression reported in PR middle-end/8808 showed up starting
with this patch:

Tue Feb 13 13:31:33 CET 2001  Jan Hubicka  <jh@suse.cz>

	* i386.c (print_reg): Use ANY_FP_REG instead of FP_REG
	* i386.h (MASK_128BIT_LONG_DOUBLE): Renumber
	(MASK_SSE2): New.
	(MASK_MIX_SSE_I387): New.
	(TARGET_SSE): SSE2 imply SSE.
	(TARGET_SSE2, TARGET_MIX_SSE_I387): New.
	(TARGET_SWITCHES): Add "sse2", "mix-sse-i387".
	(enum reg_class): Add new classes.
	(REG_CLASS_NAMES): Likewise.
	(REG_CLASS_CONTENTS): Likewise.
	(ANY_FP_REG_P, ANY_FP_REGNO_P, SSE_REG_P, SSE_FLOAT_MODE): New macros.
	(REG_CLASS_FROM_LETTER): 'x' and 'y' is SSE_REGS only when SSE is
	supported. Add 'Y' to be SSE_REGS when SSE2 is supported.
	(CLASS_MAX_NREGS): Use new macros.
	(REGISTER_MOVE_COST): Rewrite using SECONDARY_MEMORY_MAYBE_NEEDED.
	* i386.md (pushsf, movsf): Support SSE.
	(pushdf_nointeger, pushdf_integer, pushdf): Support SSE, update
	splitters to use ANY_FP_REGNO_P.
	(movdf_nointeger, movdf_integer): Likewise.

Here's a small test case that causes the compiler to ICE when compiled
on i686-linux:

-------------------
void f(unsigned long long int);

void g () {
  register unsigned long long int i asm ("mm0");
  f(i);
}
-------------------

Output from the compiler (current mainline):

8808.c: In function `g':
8808.c:6: error: insn does not satisfy its constraints:
(insn 18 23 28 (nil) (set (mem:DI (plus:SI (reg/f:SI 6 ebp)
                (const_int -8 [0xfffffff8])) [0 S8 A8])
        (reg/v:DI 29 rmm0)) 59 {*movdi_2} (nil)
    (nil))
8808.c:6: internal compiler error: in extract_constrain_insn_cached, at recog.c:2092
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.

The test compiles with -march=pentium4; perhaps the compiler should
validate asm instructions against the target architecture and give
a meaningful error message in this case.

I'll add this information to the PR.

Janis