When I worked at AMD, I was starting to suspect that it may be more beneficial to re-enable the first schedule insns pass if you were compiling in 64-bit mode, since you have more registers available, and the new registers do not have hard wired uses, which in the past always meant a lot of spills (also, the default floating point unit is SSE instead of the x87 stack). I never got around to testing this before AMD and I parted company.
Unfortunately, hardwired use of %ecx for shifts is still enough to kill -fschedule-insns on AMD64.
Paolo
