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Re: What to do with new-ra for GCC 4.0


happen to replace or significantly rewrite reload[1].

I disagree that one needs to do significant work to reload in order to get
better register allocation.

You haven't actually disagreed with me.
Fact: Reload ends up replacing most of your spill code with more spill code anyway, as it currently stands.


You have simply stated that if the register allocator did more constraint handling, this would not happen.
I don't disagree with this. In fact, i violently agree. However, the part you've missed is that as it stands, because of how the compiler is structured, this would require moving a significant amount of reload to before register allocation.


Thus, you'd have to significantly rewrite reload into a pre-ra reload.

This is what pre-reload does on new-ra, but it ends up looking just like reload.


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