------- Comment #4 from hjl dot tools at gmail dot com 2009-06-17 20:01 ------- Another testcase: [hjl@gnu-6 gcc]$ cat /tmp/pr40470-3.c #include __m128i load (char *); char * foo (char *p1, char *p2, int bmsk, __m128i mask1, __m128i mask2) { int len = 0; __m128i frag1, frag2; int cmp_s; if( !p2[0]) return p1; if( !p1[0] ) return NULL; frag2 = load (p2); frag1 = load (p1); frag2 = _mm_blendv_epi8(frag2, mask2, mask1); frag1 = _mm_blendv_epi8(frag1, mask1, mask2); cmp_s = _mm_cmpistrs(frag2, frag1, 0x0c); if( cmp_s ) __asm("bsfl %[bmsk], %[len]" : [len] "=r" (len) : [bmsk] "r" (bmsk) ); return p1 + len; } [hjl@gnu-6 gcc]$ ./xgcc -B./ -O2 -msse4 /tmp/pr40470-3.c -S -fno-asynchronous-unwind-tables /tmp/pr40470-3.c: In function ‘foo’: /tmp/pr40470-3.c:20:1: error: unable to find a register to spill in class ‘SSE_FIRST_REG’ /tmp/pr40470-3.c:20:1: error: this is the insn: (insn 30 87 32 4 ./include/smmintrin.h:62 (set (reg:V16QI 25 xmm4 [82]) (unspec:V16QI [ (subreg:V16QI (reg/v:V2DI 25 xmm4 [orig:60 frag2 ] [60]) 0) (reg:V16QI 22 xmm1 [orig:64 D.8164 ] [64]) (reg:V16QI 23 xmm2 [orig:63 D.8165 ] [63]) ] 134)) 1791 {*sse4_1_pblendvb} (expr_list:REG_DEAD (reg/v:V2DI 25 xmm4 [orig:60 frag2 ] [60]) (nil))) /tmp/pr40470-3.c:20:1: internal compiler error: in spill_failure, at reload1.c:2094 Please submit a full bug report, with preprocessed source if appropriate. See for instructions. [hjl@gnu-6 gcc]$ -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40470