Hi All,
Builing on top of the previous patch, similar to when we have a single exit if
we have a case where all exits are considered early exits and there are existing
non virtual phi then in order to maintain LCSSA we have to use the existing PHI
variables. We can't simply clear them and just rebuild them because the order
of the PHIs in the main exit must match the original exit for when we add the
skip_epilog guard.
But the infrastructure is already in place to maintain them, we just have to use
the right value.
Bootstrapped Regtested on aarch64-none-linux-gnu, x86_64-pc-linux-gnu
and no issues normally and with with --enable-checking=release --enable-lto
--with-build-config=bootstrap-O3 --enable-checking=yes,rtl,extra.
Ok for master?
Thanks,
Tamar
gcc/ChangeLog:
PR tree-optimization/113237
* tree-vect-loop-manip.cc (slpeel_tree_duplicate_loop_to_edge_cfg): Use
existing LCSSA variable for exit when all exits are early break.
gcc/testsuite/ChangeLog:
PR tree-optimization/113237
* gcc.dg/vect/vect-early-break_98-pr113237.c: New test.
--- inline copy of patch --
diff --git a/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
b/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
new file mode 100644
index
0000000000000000000000000000000000000000..e6d150b571f753e9eb3859f06f62b371817494a3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-add-options vect_early_break } */
+/* { dg-require-effective-target vect_early_break } */
+/* { dg-require-effective-target vect_int } */
+
+long Perl_pp_split_limit;
+int Perl_block_gimme();
+int Perl_pp_split() {
+ char strend;
+ long iters;
+ int gimme = Perl_block_gimme();
+ while (--Perl_pp_split_limit) {
+ if (gimme)
+ iters++;
+ if (strend)
+ break;
+ }
+ if (iters)
+ return 0;
+}
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index
7fd6566341b4893a1e209d1f8ff65d6d180f1190..77649b84f45b9e5dacec2809e0c854c8fcc17ce1
100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -1700,7 +1700,12 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop
*loop, edge loop_exit,
if (peeled_iters && !virtual_operand_p (new_arg))
{
tree tmp_arg = gimple_phi_result (from_phi);
- if (!new_phi_args.get (tmp_arg))
+ /* Similar to the single exit case, If we have an existing
+ LCSSA variable thread through the original value otherwise
+ skip it and directly use the final value. */
+ if (tree *res = new_phi_args.get (tmp_arg))
+ new_arg = *res;
+ else
new_arg = tmp_arg;
}
--
diff --git a/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
b/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
new file mode 100644
index
0000000000000000000000000000000000000000..e6d150b571f753e9eb3859f06f62b371817494a3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/vect-early-break_98-pr113237.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-add-options vect_early_break } */
+/* { dg-require-effective-target vect_early_break } */
+/* { dg-require-effective-target vect_int } */
+
+long Perl_pp_split_limit;
+int Perl_block_gimme();
+int Perl_pp_split() {
+ char strend;
+ long iters;
+ int gimme = Perl_block_gimme();
+ while (--Perl_pp_split_limit) {
+ if (gimme)
+ iters++;
+ if (strend)
+ break;
+ }
+ if (iters)
+ return 0;
+}
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index
7fd6566341b4893a1e209d1f8ff65d6d180f1190..77649b84f45b9e5dacec2809e0c854c8fcc17ce1
100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -1700,7 +1700,12 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop
*loop, edge loop_exit,
if (peeled_iters && !virtual_operand_p (new_arg))
{
tree tmp_arg = gimple_phi_result (from_phi);
- if (!new_phi_args.get (tmp_arg))
+ /* Similar to the single exit case, If we have an existing
+ LCSSA variable thread through the original value otherwise
+ skip it and directly use the final value. */
+ if (tree *res = new_phi_args.get (tmp_arg))
+ new_arg = *res;
+ else
new_arg = tmp_arg;
}
