[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
--- Comment #4 from pinskia at gcc dot gnu dot org 2009-02-06 01:45 --- (In reply to comment #3) Are the casts actually needed in this case? It seems the get introduced very early on, the .original dump already has: Yes because char = char + char is really char = (char)((int)char + (int)char); So this is dup of bug 26128. *** This bug has been marked as a duplicate of 26128 *** -- pinskia at gcc dot gnu dot org changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution||DUPLICATE http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068
[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
--- Comment #5 from pinskia at gcc dot gnu dot org 2009-02-06 01:51 --- (In reply to comment #4) Yes because char = char + char is really char = (char)((int)char + (int)char); Let me expand on that. ((char)CHAR_MAX) + 1 is well defined and there is no overflow that occurs. Since GCC internally assumes signed integer overflow is undefined, it has to convert it to be the well defined unsigned integer version. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068
[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
--- Comment #3 from dann at godzilla dot ics dot uci dot edu 2009-02-02 16:42 --- (In reply to comment #2) (reminds me of a couple missed-optimization PRs where vectorization is also failing due to casts - PR31873 , PR26128 - don't know if this is related) Are the casts actually needed in this case? It seems the get introduced very early on, the .original dump already has: a[i] = (short int) ((short unsigned int) b[i] + (short unsigned int) c[i]); -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068
[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
--- Comment #1 from rguenth at gcc dot gnu dot org 2009-02-01 20:50 --- *** Bug 39069 has been marked as a duplicate of this bug. *** -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068
[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
-- rguenth at gcc dot gnu dot org changed: What|Removed |Added Severity|normal |enhancement Keywords||missed-optimization http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068
[Bug tree-optimization/39068] signed short plus and signed char plus not vectorized
--- Comment #2 from dorit at gcc dot gnu dot org 2009-02-01 21:06 --- (reminds me of a couple missed-optimization PRs where vectorization is also failing due to casts - PR31873 , PR26128 - don't know if this is related) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39068