Re: Fix type of SRAed enum accesses

[Richard Guenther <richard.guenther@gmail.com>]

On Tue, Sep 27, 2011 at 4:26 PM, Richard Sandiford
<richard.sandiford@linaro.org> wrote:
> This patch fixes a miscompilation of stage1 c-parser.o in an ARM bootstrap.
> When an access to an enum field was SRAed, a component ref used the type
> of the integer temporary variable instead of the type of the enum.
> It therefore didn't alias other accesses to the same structure,
> and was scheduled after a copy-load.
>
> Tested on x86_64-linux-gnu, and by verifying that c-parser.o is correctly
> compiled for ARM after the patch.  Martin says he's going to test on ia64
> too (thanks) -- I'll add 50326 to the changelog if that goes OK.
>
> OK to install if there are no regressions on ia64?

Ok.

Thanks,
Richard.

> Richard
>
>
> gcc/
>        PR middle-end/50386
>        * tree-sra.c (build_ref_for_model): Use the type of the field as
>        the type of the COMPONENT_REF.
>
> Index: gcc/tree-sra.c
> ===================================================================
> --- gcc/tree-sra.c      2011-09-12 09:09:34.000000000 +0100
> +++ gcc/tree-sra.c      2011-09-27 14:09:45.379960167 +0100
> @@ -1504,7 +1504,7 @@ build_ref_for_model (location_t loc, tre
>       offset -= TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (fld));
>       exp_type = TREE_TYPE (TREE_OPERAND (model->expr, 0));
>       t = build_ref_for_offset (loc, base, offset, exp_type, gsi, insert_after);
> -      return fold_build3_loc (loc, COMPONENT_REF, model->type, t, fld,
> +      return fold_build3_loc (loc, COMPONENT_REF, TREE_TYPE (fld), t, fld,
>                              TREE_OPERAND (model->expr, 2));
>     }
>   else
>