[Bug middle-end/28283] SuperH: Very unoptimal code generated for 64-bit ints

[amylaar at gcc dot gnu dot org]

------- Comment #4 from amylaar at gcc dot gnu dot org  2006-07-06 19:32 -------
(In reply to comment #2)
> Investigating...  I suspect that the SH backend's rtx_costs are parameterized
> incorrectly, such that a 64-bit shift by the constant 32, looks to be at least
> 32 times more expensive than a 64-bit addition.

No, the costs are correct, no DImode shift is supported with a count other than
one.  The expanders are supposed to use SImode shifts.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28283