[Bug other/19815] Documentation change - GCC Internals MODES_TIEABLE_P

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=19815

Eric Gallager  changed:

   What|Removed |Added

 Status|WAITING |RESOLVED
 CC||egallager at gcc dot gnu.org
 Resolution|--- |INVALID

--- Comment #3 from Eric Gallager  ---
(In reply to Richard Biener from comment #2)
> Is this still an issue?

Reporter never replied; guess not

[Bug other/19815] Documentation change - GCC Internals MODES_TIEABLE_P

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19815

Richard Guenther rguenth at gcc dot gnu.org changed:

   What|Removed |Added

 Status|UNCONFIRMED |WAITING
   Last reconfirmed||2012-01-11
 Ever Confirmed|0   |1

--- Comment #2 from Richard Guenther rguenth at gcc dot gnu.org 2012-01-11 
12:46:52 UTC ---
Is this still an issue?

[Bug other/19815] Documentation change - GCC Internals MODES_TIEABLE_P

[abnikant dot singh at atmel dot com]

--- Comment #1 from abnikant dot singh at atmel dot com  2009-08-19 11:57 
---
If HARD_REGNO_MODE_OK (r, mode1) and HARD_REGNO_MODE_OK (r, mode2) are always
the same for any r, then MODES_TIEABLE_P (mode1, mode2) should be nonzero. If
they differ for any r, you should define this macro to return zero unless some
other mechanism ensures the accessibility of the value in a narrower mode.

In case of avr:
if (mode1 != mode2) then HARD_REGNO_MODE_OK (r, mode1) != HARD_REGNO_MODE_OK
(r, mode2) and hence MODES_TIEABLE_P (mode1, mode2) should be 0. [ But this is
true only if we do not have other mechanism to access the value in narrower
mode ]


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19815

[Bug other/19815] Documentation change - GCC Internals MODES_TIEABLE_P

[ericw at evcohs dot com]

-- 
   What|Removed |Added

 CC||ericw at evcohs dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19815