===================================================================
@@ -3440,6 +3440,22 @@ subreg_get_info (unsigned int xregno, ma
info->offset = offset / regsize_xmode;
return;
}
+ /* Quick exit for the simple and common case of extracting whole
+ subregisters from a multiregister value. */
+ /* ??? It would be better to integrate this into the code below,
+ if we can generalize the concept enough and figure out how
+ odd-sized modes can coexist with the other weird cases we support. */
+ if (!rknown
+ && WORDS_BIG_ENDIAN == REG_WORDS_BIG_ENDIAN
+ && regsize_xmode == regsize_ymode
+ && (offset % regsize_ymode) == 0)
+ {
+ info->representable_p = true;
+ info->nregs = nregs_ymode;
+ info->offset = offset / regsize_ymode;
+ gcc_assert (info->offset + info->nregs <= nregs_xmode);
+ return;
+ }
}
/* Lowpart subregs are otherwise valid. */