* [PATCH] middle-end: don't keep .MEM guard nodes for PHI nodes who dominate loop [PR111860]
@ 2023-10-20 13:55 Tamar Christina
2023-10-23 8:21 ` Richard Biener
0 siblings, 1 reply; 2+ messages in thread
From: Tamar Christina @ 2023-10-20 13:55 UTC (permalink / raw)
To: gcc-patches; +Cc: nd, rguenther, jlaw
[-- Attachment #1: Type: text/plain, Size: 4815 bytes --]
Hi All,
The previous patch tried to remove PHI nodes that dominated the first loop,
however the correct fix is to only remove .MEM nodes.
This patch thus makes the condition a bit stricter and only tries to remove
MEM phi nodes.
I couldn't figure out a way to easily determine if a particular PHI is vUSE
related, so the patch does:
1. check if the definition is a vDEF and not defined in main loop.
2. check if the definition is a PHI and not defined in main loop.
3. check if the definition is a default definition.
For no 2 and 3 we may misidentify the PHI, in both cases the value is defined
outside of the loop version block which also makes it ok to remove.
Bootstrapped Regtested on aarch64-none-linux-gnu, powerpc64le-unknown-linux-gnu,
x86_64-none-linux-gnu and no issues.
Tested all default testsuites.
Ok for master?
Thanks,
Tamar
gcc/ChangeLog:
PR tree-optimization/111860
* tree-vect-loop-manip.cc (slpeel_tree_duplicate_loop_to_edge_cfg):
Drop .MEM nodes only.
gcc/testsuite/ChangeLog:
PR tree-optimization/111860
* gcc.dg/vect/pr111860-2.c: New test.
* gcc.dg/vect/pr111860-3.c: New test.
--- inline copy of patch --
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-2.c b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
+int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
+
+int
+buffer_ctrl (long ret, int i)
+{
+ switch (buffer_ctrl_cmd)
+ {
+ case 1:
+ buffer_ctrl_ctx_0 = 0;
+ for (; i; i++)
+ if (buffer_ctrl_p1)
+ ret++;
+ }
+ return ret;
+}
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-3.c b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
new file mode 100644
index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
+int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
+
+int
+buffer_ctrl (long ret, int i)
+{
+ switch (buffer_ctrl_cmd)
+ {
+ case 1:
+ buffer_ctrl_ctx_0 = 0;
+ for (; i; i++)
+ if (buffer_ctrl_p1)
+ ret++;
+ }
+ return ret;
+}
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860.c b/gcc/testsuite/gcc.dg/vect/pr111860.c
new file mode 100644
index 0000000000000000000000000000000000000000..36f0774601040418bc6b7f27c9425b2bf93b18cb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+
+int optimize_path_n, optimize_path_d;
+int *optimize_path_d_0;
+extern void path_threeOpt( long);
+void optimize_path() {
+ int i;
+ long length;
+ i = 0;
+ for (; i <= optimize_path_n; i++)
+ optimize_path_d = 0;
+ i = 0;
+ for (; i < optimize_path_n; i++)
+ length += optimize_path_d_0[i];
+ path_threeOpt(length);
+}
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 1f7779b9834c3aef3c6a993fab916224fab03147..fc55278e63f7a48943fdc32c5e207110cf14507e 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -1626,13 +1626,33 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop *loop, edge loop_exit,
edge temp_e = redirect_edge_and_branch (exit, new_preheader);
flush_pending_stmts (temp_e);
}
-
/* Record the new SSA names in the cache so that we can skip materializing
them again when we fill in the rest of the LCSSA variables. */
for (auto phi : new_phis)
{
tree new_arg = gimple_phi_arg (phi, 0)->def;
new_phi_args.put (new_arg, gimple_phi_result (phi));
+
+ if (!SSA_VAR_P (new_arg))
+ continue;
+ /* If the PHI MEM node dominates the loop then we shouldn't create
+ a new LC-SSSA PHI for it in the intermediate block. */
+ gimple *def_stmt = SSA_NAME_DEF_STMT (new_arg);
+ basic_block def_bb = gimple_bb (def_stmt);
+ /* A MEM phi that consitutes a new DEF for the vUSE chain can either
+ be a .VDEF or a PHI that operates on MEM. */
+ if (((gimple_vdef (def_stmt) || is_a <gphi *> (def_stmt))
+ /* And said definition must not be inside the main loop. */
+ && (!def_bb || !flow_bb_inside_loop_p (loop, def_bb)))
+ /* Or we must be a parameter. In the last two cases we may remove
+ a non-MEM PHI node, but since they dominate both loops the
+ removal is unlikely to cause trouble as the exits must already
+ be using them. */
+ || SSA_NAME_IS_DEFAULT_DEF (new_arg))
+ {
+ auto gsi = gsi_for_stmt (phi);
+ remove_phi_node (&gsi, true);
+ }
}
/* Copy the current loop LC PHI nodes between the original loop exit
--
[-- Attachment #2: rb17863.patch --]
[-- Type: text/plain, Size: 3656 bytes --]
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-2.c b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
+int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
+
+int
+buffer_ctrl (long ret, int i)
+{
+ switch (buffer_ctrl_cmd)
+ {
+ case 1:
+ buffer_ctrl_ctx_0 = 0;
+ for (; i; i++)
+ if (buffer_ctrl_p1)
+ ret++;
+ }
+ return ret;
+}
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-3.c b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
new file mode 100644
index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
+int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
+
+int
+buffer_ctrl (long ret, int i)
+{
+ switch (buffer_ctrl_cmd)
+ {
+ case 1:
+ buffer_ctrl_ctx_0 = 0;
+ for (; i; i++)
+ if (buffer_ctrl_p1)
+ ret++;
+ }
+ return ret;
+}
diff --git a/gcc/testsuite/gcc.dg/vect/pr111860.c b/gcc/testsuite/gcc.dg/vect/pr111860.c
new file mode 100644
index 0000000000000000000000000000000000000000..36f0774601040418bc6b7f27c9425b2bf93b18cb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr111860.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+
+int optimize_path_n, optimize_path_d;
+int *optimize_path_d_0;
+extern void path_threeOpt( long);
+void optimize_path() {
+ int i;
+ long length;
+ i = 0;
+ for (; i <= optimize_path_n; i++)
+ optimize_path_d = 0;
+ i = 0;
+ for (; i < optimize_path_n; i++)
+ length += optimize_path_d_0[i];
+ path_threeOpt(length);
+}
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 1f7779b9834c3aef3c6a993fab916224fab03147..fc55278e63f7a48943fdc32c5e207110cf14507e 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -1626,13 +1626,33 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop *loop, edge loop_exit,
edge temp_e = redirect_edge_and_branch (exit, new_preheader);
flush_pending_stmts (temp_e);
}
-
/* Record the new SSA names in the cache so that we can skip materializing
them again when we fill in the rest of the LCSSA variables. */
for (auto phi : new_phis)
{
tree new_arg = gimple_phi_arg (phi, 0)->def;
new_phi_args.put (new_arg, gimple_phi_result (phi));
+
+ if (!SSA_VAR_P (new_arg))
+ continue;
+ /* If the PHI MEM node dominates the loop then we shouldn't create
+ a new LC-SSSA PHI for it in the intermediate block. */
+ gimple *def_stmt = SSA_NAME_DEF_STMT (new_arg);
+ basic_block def_bb = gimple_bb (def_stmt);
+ /* A MEM phi that consitutes a new DEF for the vUSE chain can either
+ be a .VDEF or a PHI that operates on MEM. */
+ if (((gimple_vdef (def_stmt) || is_a <gphi *> (def_stmt))
+ /* And said definition must not be inside the main loop. */
+ && (!def_bb || !flow_bb_inside_loop_p (loop, def_bb)))
+ /* Or we must be a parameter. In the last two cases we may remove
+ a non-MEM PHI node, but since they dominate both loops the
+ removal is unlikely to cause trouble as the exits must already
+ be using them. */
+ || SSA_NAME_IS_DEFAULT_DEF (new_arg))
+ {
+ auto gsi = gsi_for_stmt (phi);
+ remove_phi_node (&gsi, true);
+ }
}
/* Copy the current loop LC PHI nodes between the original loop exit
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH] middle-end: don't keep .MEM guard nodes for PHI nodes who dominate loop [PR111860]
2023-10-20 13:55 [PATCH] middle-end: don't keep .MEM guard nodes for PHI nodes who dominate loop [PR111860] Tamar Christina
@ 2023-10-23 8:21 ` Richard Biener
0 siblings, 0 replies; 2+ messages in thread
From: Richard Biener @ 2023-10-23 8:21 UTC (permalink / raw)
To: Tamar Christina; +Cc: gcc-patches, nd, jlaw
On Fri, 20 Oct 2023, Tamar Christina wrote:
> Hi All,
>
> The previous patch tried to remove PHI nodes that dominated the first loop,
> however the correct fix is to only remove .MEM nodes.
>
> This patch thus makes the condition a bit stricter and only tries to remove
> MEM phi nodes.
>
> I couldn't figure out a way to easily determine if a particular PHI is vUSE
> related, so the patch does:
>
> 1. check if the definition is a vDEF and not defined in main loop.
> 2. check if the definition is a PHI and not defined in main loop.
> 3. check if the definition is a default definition.
>
> For no 2 and 3 we may misidentify the PHI, in both cases the value is defined
> outside of the loop version block which also makes it ok to remove.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu, powerpc64le-unknown-linux-gnu,
> x86_64-none-linux-gnu and no issues.
>
> Tested all default testsuites.
>
> Ok for master?
>
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> PR tree-optimization/111860
> * tree-vect-loop-manip.cc (slpeel_tree_duplicate_loop_to_edge_cfg):
> Drop .MEM nodes only.
>
> gcc/testsuite/ChangeLog:
>
> PR tree-optimization/111860
> * gcc.dg/vect/pr111860-2.c: New test.
> * gcc.dg/vect/pr111860-3.c: New test.
>
> --- inline copy of patch --
> diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-2.c b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/pr111860-2.c
> @@ -0,0 +1,17 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
> +int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
> +
> +int
> +buffer_ctrl (long ret, int i)
> +{
> + switch (buffer_ctrl_cmd)
> + {
> + case 1:
> + buffer_ctrl_ctx_0 = 0;
> + for (; i; i++)
> + if (buffer_ctrl_p1)
> + ret++;
> + }
> + return ret;
> +}
> diff --git a/gcc/testsuite/gcc.dg/vect/pr111860-3.c b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..07f64ffb5318c9d7817d46802d123cc9a2d65ec9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/pr111860-3.c
> @@ -0,0 +1,17 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fno-tree-sink -ftree-vectorize" } */
> +int buffer_ctrl_ctx_0, buffer_ctrl_p1, buffer_ctrl_cmd;
> +
> +int
> +buffer_ctrl (long ret, int i)
> +{
> + switch (buffer_ctrl_cmd)
> + {
> + case 1:
> + buffer_ctrl_ctx_0 = 0;
> + for (; i; i++)
> + if (buffer_ctrl_p1)
> + ret++;
> + }
> + return ret;
> +}
> diff --git a/gcc/testsuite/gcc.dg/vect/pr111860.c b/gcc/testsuite/gcc.dg/vect/pr111860.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..36f0774601040418bc6b7f27c9425b2bf93b18cb
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/pr111860.c
> @@ -0,0 +1,16 @@
> +/* { dg-do compile } */
> +
> +int optimize_path_n, optimize_path_d;
> +int *optimize_path_d_0;
> +extern void path_threeOpt( long);
> +void optimize_path() {
> + int i;
> + long length;
> + i = 0;
> + for (; i <= optimize_path_n; i++)
> + optimize_path_d = 0;
> + i = 0;
> + for (; i < optimize_path_n; i++)
> + length += optimize_path_d_0[i];
> + path_threeOpt(length);
> +}
> diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
> index 1f7779b9834c3aef3c6a993fab916224fab03147..fc55278e63f7a48943fdc32c5e207110cf14507e 100644
> --- a/gcc/tree-vect-loop-manip.cc
> +++ b/gcc/tree-vect-loop-manip.cc
> @@ -1626,13 +1626,33 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop *loop, edge loop_exit,
> edge temp_e = redirect_edge_and_branch (exit, new_preheader);
> flush_pending_stmts (temp_e);
> }
> -
> /* Record the new SSA names in the cache so that we can skip materializing
> them again when we fill in the rest of the LCSSA variables. */
> for (auto phi : new_phis)
> {
> tree new_arg = gimple_phi_arg (phi, 0)->def;
> new_phi_args.put (new_arg, gimple_phi_result (phi));
don't you want to skip this as well?
> +
> + if (!SSA_VAR_P (new_arg))
> + continue;
> + /* If the PHI MEM node dominates the loop then we shouldn't create
> + a new LC-SSSA PHI for it in the intermediate block. */
> + gimple *def_stmt = SSA_NAME_DEF_STMT (new_arg);
> + basic_block def_bb = gimple_bb (def_stmt);
> + /* A MEM phi that consitutes a new DEF for the vUSE chain can either
> + be a .VDEF or a PHI that operates on MEM. */
> + if (((gimple_vdef (def_stmt) || is_a <gphi *> (def_stmt))
> + /* And said definition must not be inside the main loop. */
> + && (!def_bb || !flow_bb_inside_loop_p (loop, def_bb)))
> + /* Or we must be a parameter. In the last two cases we may remove
> + a non-MEM PHI node, but since they dominate both loops the
> + removal is unlikely to cause trouble as the exits must already
> + be using them. */
> + || SSA_NAME_IS_DEFAULT_DEF (new_arg))
> + {
> + auto gsi = gsi_for_stmt (phi);
> + remove_phi_node (&gsi, true);
> + }
May I suggest the simpler
gimple *def;
if (virtual_operand_p (new_arg)
&& (SSA_NAME_IS_DEFAULT_DEF (new_arg)
|| !flow_bb_inside_loop_p (loop,
gimple_bb (SSA_NAME_DEF_STMT (new_arg))))
{
> + auto gsi = gsi_for_stmt (phi);
> + remove_phi_node (&gsi, true);
}
?
OK with that change.
Richard.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2023-10-23 8:21 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-10-20 13:55 [PATCH] middle-end: don't keep .MEM guard nodes for PHI nodes who dominate loop [PR111860] Tamar Christina
2023-10-23 8:21 ` Richard Biener
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).