http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50107
--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> 2011-08-17 19:16:40 UTC --- Created attachment 25038 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25038 A patch This patch generates: movq %rdi, %rdx mulx %rsi, %r10, %r9 addq $3, %r9 adcq $0, %r10 movq %r9, k2(%rip) movq %r9, %rax movq %r10, k2+8(%rip) movq %r10, %rdx ret