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Re: [PATCH, ARM] stop changing signedness in PROMOTE_MODE
- From: Jim Wilson <jim dot wilson at linaro dot org>
- To: Richard Biener <richard dot guenther at gmail dot com>
- Cc: Jeff Law <law at redhat dot com>, "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Fri, 10 Jul 2015 08:46:38 -0700
- Subject: Re: [PATCH, ARM] stop changing signedness in PROMOTE_MODE
- Authentication-results: sourceware.org; auth=none
- References: <CABXYE2VXjy7=5Y=c1TCxLE8KuwLtwBYBhTB24xrWDvWAeiBwbQ at mail dot gmail dot com> <559BEB2D dot 7040800 at redhat dot com> <CABXYE2UbBP24fBEgDJp5+S1fhFpNHPJgjM=SypsWbc4hV1xbbw at mail dot gmail dot com> <DDEC7CC8-74EE-4ACF-97C8-EE5A7D53CDB6 at gmail dot com>
On Tue, Jul 7, 2015 at 2:35 PM, Richard Biener
<richard.guenther@gmail.com> wrote:
> On July 7, 2015 6:29:21 PM GMT+02:00, Jim Wilson <jim.wilson@linaro.org> wrote:
>>signed sub-word locals. Thus to detect the need for a conversion, you
>>have to have the decls, and we don't have them here. There is also
>
> It probably is. The decks for the parameter based SSA names are available, for the PHI destination there might be no decl.
I tried looking again, and found the decls. I'm able to get correct
code for my testcase with the attached patch to force the conversion.
It is rather inelegant, but I think I can cache the values I need to
make this simpler and cleaner. I still don't have decls from
insert_part_to_rtx_on_edge and insert_rtx_to_part_on_edge, but it
looks like those are for breaking cycles, and hence might not need
conversions.
Jim
Index: tree-outof-ssa.c
===================================================================
--- tree-outof-ssa.c (revision 225477)
+++ tree-outof-ssa.c (working copy)
@@ -230,11 +230,32 @@ set_location_for_edge (edge e)
SRC/DEST might be BLKmode memory locations SIZEEXP is a tree from
which we deduce the size to copy in that case. */
-static inline rtx_insn *
-emit_partition_copy (rtx dest, rtx src, int unsignedsrcp, tree sizeexp)
+rtx_insn *
+emit_partition_copy (rtx dest, rtx src, int unsignedsrcp, tree sizeexp,
+ tree var2 ATTRIBUTE_UNUSED)
{
start_sequence ();
+ /* If var2 is set, then sizeexp is the src decl and var2 is the dest decl. */
+ if (var2)
+ {
+ tree src_var = (TREE_CODE (sizeexp) == SSA_NAME
+ ? SSA_NAME_VAR (sizeexp) : sizeexp);
+ tree dest_var = (TREE_CODE (var2) == SSA_NAME
+ ? SSA_NAME_VAR (var2) : var2);
+ int src_unsignedp = TYPE_UNSIGNED (TREE_TYPE (src_var));
+ int dest_unsignedp = TYPE_UNSIGNED (TREE_TYPE (dest_var));
+ machine_mode src_mode = promote_decl_mode (src_var, &src_unsignedp);
+ machine_mode dest_mode = promote_decl_mode (dest_var, &dest_unsignedp);
+ if (src_unsignedp != dest_unsignedp
+ && src_mode != DECL_MODE (src_var)
+ && dest_mode != DECL_MODE (dest_var))
+ {
+ src = gen_lowpart_common (DECL_MODE (src_var), src);
+ unsignedsrcp = dest_unsignedp;
+ }
+ }
+
if (GET_MODE (src) != VOIDmode && GET_MODE (src) != GET_MODE (dest))
src = convert_to_mode (GET_MODE (dest), src, unsignedsrcp);
if (GET_MODE (src) == BLKmode)
@@ -256,7 +277,7 @@ emit_partition_copy (rtx dest, rtx src,
static void
insert_partition_copy_on_edge (edge e, int dest, int src, source_location locus)
{
- tree var;
+ tree var, var2;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file,
@@ -276,10 +297,11 @@ insert_partition_copy_on_edge (edge e, i
set_curr_insn_location (locus);
var = partition_to_var (SA.map, src);
+ var2 = partition_to_var (SA.map, dest);
rtx_insn *seq = emit_partition_copy (copy_rtx (SA.partition_to_pseudo[dest]),
copy_rtx (SA.partition_to_pseudo[src]),
TYPE_UNSIGNED (TREE_TYPE (var)),
- var);
+ var, var2);
insert_insn_on_edge (seq, e);
}
@@ -373,7 +395,8 @@ insert_rtx_to_part_on_edge (edge e, int
involved), so it doesn't matter. */
rtx_insn *seq = emit_partition_copy (copy_rtx (SA.partition_to_pseudo[dest]),
src, unsignedsrcp,
- partition_to_var (SA.map, dest));
+ partition_to_var (SA.map, dest), 0);
+
insert_insn_on_edge (seq, e);
}
@@ -406,7 +429,7 @@ insert_part_to_rtx_on_edge (edge e, rtx
rtx_insn *seq = emit_partition_copy (dest,
copy_rtx (SA.partition_to_pseudo[src]),
TYPE_UNSIGNED (TREE_TYPE (var)),
- var);
+ var, 0);
insert_insn_on_edge (seq, e);
}