This is the mail archive of the gcc-bugs@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug target/36090] [4.3/4.4 Regression] ppc64 cacoshl miscompilation



------- Comment #11 from jakub at gcc dot gnu dot org  2008-05-02 09:34 -------
The unexpected address is created by simplify_plus_minus on
(plus:DI (reg:DI 2 2)
    (const:DI (minus:DI (symbol_ref/u:DI ("*.LC1") [flags 0x2])
            (symbol_ref:DI ("*.LCTOC1")))))
and
(const_int 8 [0x8])
where the .LCTOC1 and +8 pair is simplified together.  Unfortunately, if we
refuse it in rs6000_legitimate_address, fwprop doesn't try harder
(LEGITIMIZE_ADDRESS/memory_address isn't called) and nothing afterwards
propagates it either, so we end up with:
la 9,.LC1@toc(2)
ld 0,8(9)
instead of
ld 0,.LC1@toc+8(2)
So I'm afraid we want to accept it.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36090


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]