[gcc r11-10014] tree-optimization/105148 - fix IVOPTs recording uses

[gcc r11-10014] tree-optimization/105148 - fix IVOPTs recording uses

[Richard Biener]

https://gcc.gnu.org/g:64b3a86d33e08072ea78f2a87c8a275bd15f07cb

commit r11-10014-g64b3a86d33e08072ea78f2a87c8a275bd15f07cb
Author: Richard Biener <rguenther@suse.de>
Date:   Tue Apr 5 16:06:10 2022 +0200

    tree-optimization/105148 - fix IVOPTs recording uses
    
    The following fixes recording uses in ARRAY_REFs with non-constant
    element size or low bound.
    
    2022-04-05  Richard Biener  <rguenther@suse.de>
    
            PR tree-optimization/105148
            * tree-ssa-loop-ivopts.c (idx_record_use): Walk raw operands
            2 and 3 of ARRAY_REFs.
    
            * gcc.dg/torture/pr105148.c: New testcase.
    
    (cherry picked from commit 86242eb1bd03eba82d8e22b01b16925d43bcc539)

Diff:
---
 gcc/testsuite/gcc.dg/torture/pr105148.c | 20 ++++++++++++++++++++
 gcc/tree-ssa-loop-ivopts.c              |  6 ++++--
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/gcc/testsuite/gcc.dg/torture/pr105148.c b/gcc/testsuite/gcc.dg/torture/pr105148.c
new file mode 100644
index 00000000000..3338b0f3281
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr105148.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+
+extern void foo (void);
+
+static inline int
+bar (int n)
+{
+  for (int i = 0; i < n; i++)
+    {
+      foo ();
+      int y[1][i];
+      y[n][i] = 0;
+    }
+}
+
+int
+baz (void)
+{
+  return bar (5);
+}
diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c
index 4012ae3f19d..913b3ad4258 100644
--- a/gcc/tree-ssa-loop-ivopts.c
+++ b/gcc/tree-ssa-loop-ivopts.c
@@ -2125,8 +2125,10 @@ idx_record_use (tree base, tree *idx,
   find_interesting_uses_op (data, *idx);
   if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF)
     {
-      find_interesting_uses_op (data, array_ref_element_size (base));
-      find_interesting_uses_op (data, array_ref_low_bound (base));
+      if (TREE_OPERAND (base, 2))
+	find_interesting_uses_op (data, TREE_OPERAND (base, 2));
+      if (TREE_OPERAND (base, 3))
+	find_interesting_uses_op (data, TREE_OPERAND (base, 3));
     }
   return true;
 }