Re: SH5 compact register numbering in gcc -> gdb interface

[Elena Zannoni <ezannoni@redhat.com>]

Joern Rennecke writes:
 > ac131313@cygnus.com wrote:
 > > Humor me here.
 > > 
 > > How do you use dwarf2 cfi to unwind a compact register (saved on the
 > > stack) back to a media register?  In addition to the address of the
 > > saved register you'll need to know that only part of the register was
 > > saved. Does CFI describe this?
 > 
 > With the proposed numbering change (2nd revision), we get different
 > numbers to describe compact an media registers.  So when only the lower
 > 32 bits are saved, gcc can use the SHcompact register number to describe
 > this.
 > 
 > N.B., the upper 32 bits of the register are actually overwritten in the
 > process.  The restore from the stack sign-extends from bit 31.  The caller
 > is responsible to make sure that no 64 bit value is live in the register.	

Yes. We seem to agree on the register numbering scheme.

Elena

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