[Bug rtl-optimization/13366] ICE using MMX/SSE builtins with -O

[uros at kss-loka dot si]

------- Additional Comments From uros at kss-loka dot si  2004-12-20 15:39 -------
Equivalent SSE2 version works OK:
typedef int v8hi __attribute__ ((mode (V8HI)));

int
f (unsigned short n)
{
  v8hi vec = { 0, 0, 0, 0, 0, 0, 1, n };
  v8hi hw = __builtin_ia32_pmulhw128 (vec, vec);
  return (__builtin_ia32_pextrw128 (hw, 0));
}

SSE2 example produces following RTL:
(insn 13 11 15 1 (set (reg/v:V8HI 59 [ vec ])
        (const_vector:V8HI [
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
            ])) -1 (nil)
    (nil))

(insn 15 13 16 1 (parallel [
            (set (subreg:SI (reg/v:V8HI 59 [ vec ]) 12)
                (and:SI (subreg:SI (reg/v:V8HI 59 [ vec ]) 12)
                    (const_int -65536 [0xffff0000])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))
...

and MMX version produces:

(insn 13 11 15 1 (clobber (reg/v:V4HI 59 [ vec ])) -1 (nil)
    (nil))

(insn 15 13 17 1 (parallel [
            (set (subreg:SI (reg/v:V4HI 59 [ vec ]) 0)
                (and:SI (subreg:SI (reg/v:V4HI 59 [ vec ]) 0)
                    (const_int -65536 [0xffff0000])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))
...

The trouble is in (insn 13). There is no setting of reg 59 to zero.

Also, mainline does not ICE for
v4hi vec = { 0, 0, 0, n };
and its SSE2 equivalent as suggested in comment #6 for both MMX and SSE2 versions.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13366