include/libfirm/irarch.h
- give the mode to the eval function

ir/be/ia32/bearch_ia32.c
- the maximum allowed shift is 63 (for double-word shifts) on x86, not 31

ir/be/ia32/ia32_architecture.c
ir/be/ia32/ia32_architecture.h
- estimate the cost for 64bit operations

ir/ir/irarch.c
- pass the mode

[r28081]