[Bug middle-end/56548] [4.8 Regression] ICE in emit_move_insn, at expr.c:3486 with -march=pentium{pro,2,3} -O3

[sje at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56548



--- Comment #7 from Steve Ellcey <sje at gcc dot gnu.org> 2013-03-06 18:22:44 
UTC ---

(In reply to comment #6)

> But you can't achieve that through generation of invalid RTL.



Agreed.



> Anyway, I wonder why nonzero_bits during combine doesn't figure out that the

> upper bits are already all zero and optimize away the masking.



That I don't know.  I have opened bug 56552 to track the issue.