https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100258
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- LLVM does: .LBB0_8: movl $1065353216, (%rsi) movl $1065353216, 12(%rsi) movl $1065353216, 24(%rsi) movl $1065353216, 36(%rsi) addq $4, %rdx addq $48, %rsi cmpq %rdx, %rcx jne .LBB0_8 In the inner loop ...