On Mon, 2 Nov 2020, Bernd Edlinger wrote: > Hi, > > this makes sure that stack allocated SSA_NAMEs are > at least MODE_ALIGNED. Also increase the MEM_ALIGN > for the corresponding rtl objects. > > > Tested on x86_64-pc-linux-gnu and arm-none-eabi. > > OK for trunk?
@@ -1022,6 +1030,14 @@ expand_one_stack_var_at (tree decl, rtx base, unsigned base_align, } set_rtl (decl, x); + + if (TREE_CODE (decl) == SSA_NAME + && GET_MODE (x) != BLKmode + && MEM_ALIGN (x) < GET_MODE_ALIGNMENT (GET_MODE (x))) + { + gcc_checking_assert (GET_MODE_ALIGNMENT (GET_MODE (x)) <= base_align); + set_mem_align (x, GET_MODE_ALIGNMENT (GET_MODE (x))); + } } I wonder whether we cannot "fix" set_rtl to not call set_mem_attributes in this path, maybe directly call set_mem_align there instead? That is, the preceeding code for ! SSA_NAME already tries to adjust alignment to honor that of the actual stack slot - IMHO the non-SSA and SSA cases should be merged after this patch, but maybe simply by calling set_mem_align instead of doing the DECL_ALIGN frobbing and do the alignment compute also for SSA_NAMEs? The other pieces look OK but the above is a bit ugly at the moment. Thanks, Richard, > > > Thanks > Bernd. > -- Richard Biener <rguent...@suse.de> SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany; GF: Felix Imend