From: Richard Sandiford <richard.sandiford@linaro.org>
Date: Tue, 16 Jan 2018 09:28:26 +0000 (+0000)
Subject: Don't group gather loads (PR83847)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=82279a515eae2b655eaba39e42e7dded25da5e2c;p=gcc.git

Don't group gather loads (PR83847)

In the testcase we were trying to group two gather loads, even though
that isn't supported.  Fixed by explicitly disallowing grouping of
gathers and scatters.

This problem didn't show up on SVE because there we convert to
IFN_GATHER_LOAD/IFN_SCATTER_STORE pattern statements, which fail
the can_group_stmts_p check.

2018-01-16  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* tree-vect-data-refs.c (vect_analyze_data_ref_accesses):

gcc/testsuite/
	* gcc.dg/torture/pr83847.c: New test.

From-SVN: r256730
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9cf937b2714..f83d351942a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2018-01-16  Richard Sandiford  <richard.sandiford@linaro.org>
+
+	* tree-vect-data-refs.c (vect_analyze_data_ref_accesses):
+
 2018-01-16  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/86620
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b4f38370f78..9bc4d7be97c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2018-01-16  Richard Sandiford  <richard.sandiford@linaro.org>
+
+	* gcc.dg/torture/pr83847.c: New test.
+
 2018-01-16  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/86620
diff --git a/gcc/testsuite/gcc.dg/torture/pr83847.c b/gcc/testsuite/gcc.dg/torture/pr83847.c
new file mode 100644
index 00000000000..e42541e1b57
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr83847.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-march=bdver4" { target i?86-*-* x86_64-*-* } } */
+
+typedef struct {
+  struct {
+    int a;
+    int b;
+  } c;
+} * d;
+typedef struct {
+  unsigned e;
+  d f[];
+} g;
+g h;
+d *k;
+int i(int j) {
+  if (j) {
+    *k = *h.f;
+    return 1;
+  }
+  return 0;
+}
+int l;
+int m;
+int n;
+d o;
+void p() {
+  for (; i(l); l++) {
+    n += o->c.a;
+    m += o->c.b;
+  }
+}
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index 684b7c587ea..01f7138e077 100644
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -2923,7 +2923,8 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
       data_reference_p dra = datarefs_copy[i];
       stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
       stmt_vec_info lastinfo = NULL;
-      if (! STMT_VINFO_VECTORIZABLE (stmtinfo_a))
+      if (!STMT_VINFO_VECTORIZABLE (stmtinfo_a)
+	  || STMT_VINFO_GATHER_SCATTER_P (stmtinfo_a))
 	{
 	  ++i;
 	  continue;
@@ -2932,7 +2933,8 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
 	{
 	  data_reference_p drb = datarefs_copy[i];
 	  stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
-	  if (! STMT_VINFO_VECTORIZABLE (stmtinfo_b))
+	  if (!STMT_VINFO_VECTORIZABLE (stmtinfo_b)
+	      || STMT_VINFO_GATHER_SCATTER_P (stmtinfo_b))
 	    break;
 
 	  /* ???  Imperfect sorting (non-compatible types, non-modulo