[PATCH] Generate better location ranges for some register-described variables.

[Adrian Prantl]

> On May 29, 2014, at 10:03 PM, Alexey Samsonov <vonosmas at gmail.com> wrote:
> 
> Yeah, well, we can add "FrameTeardown" machine instruction flag in addition to "FrameSetup", and annotate machine instructions added in frame lowering code. But do we expect many users of this flag (assuming that this usage is also somewhat questionable)?

The FrameSetup flag is also only used by the debug info, so at least it wouldn’t be any more questionable than that :-)

> I can also make this patch even less general and just special-case the frame pointer and the stack pointer registers, so that the code wouldn't pretend to solve a general problem we're facing.

The frame pointer should be stable over the entire function, special casing it seems to be appropriate. I don’t know whether, e.g, stack coloring would cause the stack pointer to be modified in the middle of a function.

-- adrian