Print the type of alias check in a dump message

This patch prints a message to say how an alias check is being
implemented.

2019-11-16  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-data-ref.c (create_intersect_range_checks_index)
	(create_intersect_range_checks): Print dump messages.

gcc/testsuite/
	* gcc.dg/vect/vect-alias-check-1.c: Test for the type of alias check.
	* gcc.dg/vect/vect-alias-check-8.c: Likewise.
	* gcc.dg/vect/vect-alias-check-9.c: Likewise.
	* gcc.dg/vect/vect-alias-check-10.c: Likewise.
	* gcc.dg/vect/vect-alias-check-11.c: Likewise.
	* gcc.dg/vect/vect-alias-check-12.c: Likewise.
	* gcc.dg/vect/vect-alias-check-13.c: Likewise.
	* gcc.dg/vect/vect-alias-check-14.c: Likewise.
	* gcc.dg/vect/vect-alias-check-15.c: Likewise.
	* gcc.dg/vect/vect-alias-check-16.c: Likewise.
	* gcc.dg/vect/vect-alias-check-17.c: Likewise.

From-SVN: r278353

14 files changed, 48 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 31b5afc..c194a0a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
 2019-11-16  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* tree-data-ref.c (create_intersect_range_checks_index)
+	(create_intersect_range_checks): Print dump messages.
+
+2019-11-16  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* tree-data-ref.c (dump_alias_pair): New function.
 	(prune_runtime_alias_test_list): Use it to dump each merged alias pair.
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index eb6060c..c701507 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,19 @@
 2019-11-16  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* gcc.dg/vect/vect-alias-check-1.c: Test for the type of alias check.
+	* gcc.dg/vect/vect-alias-check-8.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-9.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-10.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-11.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-12.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-13.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-14.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-15.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-16.c: Likewise.
+	* gcc.dg/vect/vect-alias-check-17.c: Likewise.
+
+2019-11-16  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* gcc.dg/vect/vect-alias-check-8.c: Test for the RAW flag.
 	* gcc.dg/vect/vect-alias-check-9.c: Test for the ARBITRARY flag.
 	(TEST_VALUE): Use a higher value for early iterations.
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-1.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-1.c
index c2b1c77..3887120 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-1.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-1.c
@@ -15,3 +15,5 @@ fn1 ()
 }
 
 /* { dg-final { scan-tree-dump "improved number of alias checks from \[0-9\]* to 1" "vect" } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-10.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-10.c
index 0e6285e..b6cc309 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-10.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-10.c
@@ -65,3 +65,6 @@ main (void)
   FOR_EACH_TYPE (DO_TEST)
   return 0;
 }
+
+/* { dg-final { scan-tree-dump-not "using an address-based" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-11.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-11.c
index a0d5abc..09a4ebf 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-11.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-11.c
@@ -95,3 +95,6 @@ main (void)
 /* { dg-final { scan-tree-dump {no alias between [^\n]* when [^\n]* step[^ ]* \* 8[)]* is outside \(-24, 24\)} "vect" { target vect_double } } } */
 /* { dg-final { scan-tree-dump {no alias between [^\n]* when [^\n]* step[^ ]* \* 8[)]* is outside \(-32, 32\)} "vect" { target vect_double } } } */
 /* { dg-final { scan-tree-dump {run-time check [^\n]* abs \([^*]* \* 8[)]* >= 32} "vect" { target vect_double } } } */
+
+/* { dg-final { scan-tree-dump-not "using an address-based" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-12.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-12.c
index 788cdfc..63a897f 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-12.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-12.c
@@ -95,3 +95,6 @@ main (void)
 /* { dg-final { scan-tree-dump {no alias between [^\n]* when [^\n]* [_a-z][^ ]* \* 8[)]* is outside \[0, 24\)} "vect" { target vect_double } } } */
 /* { dg-final { scan-tree-dump {no alias between [^\n]* when [^\n]* [_a-z][^ ]* \* 8[)]* is outside \[0, 32\)} "vect" { target vect_double } } } */
 /* { dg-final { scan-tree-dump {run-time check [^\n]* unsigned \([^*]* \* 8[)]* >= 32} "vect" { target vect_double } } } */
+
+/* { dg-final { scan-tree-dump-not "using an address-based" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-13.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-13.c
index 60bc473..812aa90 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-13.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-13.c
@@ -18,4 +18,6 @@ f2 (int *x, long step2, int n)
 
 /* { dg-final { scan-tree-dump {need run-time check that [^\n]*step1[^\n]* is nonzero} "vect" } } */
 /* { dg-final { scan-tree-dump-not {need run-time check that [^\n]*step2[^\n]* is nonzero} "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an address-based" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
 /* { dg-final { scan-tree-dump-times {LOOP VECTORIZED} 2 "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c
index 35b16b7..87045c9 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c
@@ -60,3 +60,5 @@ main (void)
 
 /* { dg-final { scan-tree-dump {flags: *WAR\n} "vect" { target vect_int } } } */
 /* { dg-final { scan-tree-dump-not {flags: [^\n]*ARBITRARY\n} "vect" } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c
index d868c43..ad8d69e 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c
@@ -57,3 +57,5 @@ main (void)
 }
 
 /* { dg-final { scan-tree-dump {flags: *WAW\n} "vect" { target vect_int } } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c
index 97ab77e..81c252d 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c
@@ -62,3 +62,5 @@ main (void)
 }
 
 /* { dg-final { scan-tree-dump {flags: *RAW\n} "vect" { target vect_int } } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c
index 0c8bec3..c49c497 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c
@@ -11,3 +11,5 @@ f (struct s *s1, int a, int b)
 }
 
 /* { dg-final { scan-tree-dump {flags: *[^\n]*MIXED_STEPS} "vect" } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c
index df19698..6cd0219 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c
@@ -60,3 +60,5 @@ main (void)
 }
 
 /* { dg-final { scan-tree-dump {flags: *WAR\n} "vect" { target vect_int } } } */
+/* { dg-final { scan-tree-dump "using an index-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an address-based" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c b/gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c
index f771462..a7fc1fc 100644
--- a/gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c
+++ b/gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c
@@ -53,3 +53,5 @@ main (void)
 }
 
 /* { dg-final { scan-tree-dump {flags: [^\n]*ARBITRARY\n} "vect" { target vect_int } } } */
+/* { dg-final { scan-tree-dump "using an address-based overlap test" "vect" } } */
+/* { dg-final { scan-tree-dump-not "using an index-based" "vect" } } */
diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 7fc401f..527cb5e 100644
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -1889,6 +1889,8 @@ create_intersect_range_checks_index (class loop *loop, tree *cond_expr,
       else
 	*cond_expr = part_cond_expr;
     }
+  if (dump_enabled_p ())
+    dump_printf (MSG_NOTE, "using an index-based overlap test\n");
   return true;
 }
 
@@ -2036,6 +2038,8 @@ create_intersect_range_checks (class loop *loop, tree *cond_expr,
     = fold_build2 (TRUTH_OR_EXPR, boolean_type_node,
 	fold_build2 (cmp_code, boolean_type_node, seg_a_max, seg_b_min),
 	fold_build2 (cmp_code, boolean_type_node, seg_b_max, seg_a_min));
+  if (dump_enabled_p ())
+    dump_printf (MSG_NOTE, "using an address-based overlap test\n");
 }
 
 /* Create a conditional expression that represents the run-time checks for