[gcc r14-7002] gimplify: Fix ICE in recalculate_side_effects [PR113228]

[Jakub Jelinek]

https://gcc.gnu.org/g:8c0dd8a6ff85d6e7b38957f2da400f5cfa8fef6b

commit r14-7002-g8c0dd8a6ff85d6e7b38957f2da400f5cfa8fef6b
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Mon Jan 8 13:59:15 2024 +0100

    gimplify: Fix ICE in recalculate_side_effects [PR113228]
    
    The following testcase ICEs during regimplificatgion since the addition of
    (convert (eqne zero_one_valued_p@0 INTEGER_CST@1))
    simplification.  That simplification is novel in the sense that in
    gimplify_expr it can turn an expression (comparison in particular) into
    a SSA_NAME.  Normally when gimplify_expr sees originally a SSA_NAME, it does
            case SSA_NAME:
              /* Allow callbacks into the gimplifier during optimization.  */
              ret = GS_ALL_DONE;
              break;
    and doesn't try to recalculate side effects because of that, but in this
    case gimplify_expr normally enters the:
            default:
              switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
                {
                case tcc_comparison:
    then does
                          *expr_p = gimple_boolify (*expr_p);
    and then
                              *expr_p = fold_convert_loc (input_location,
                                                          org_type, *expr_p);
    with this new match.pd simplification turns that tcc_comparison class
    into SSA_NAME.  Unlike the outer SSA_NAME handling though, this falls
    through into
              recalculate_side_effects (*expr_p);
    
            dont_recalculate:
              break;
    but unfortunately recalculate_side_effects doesn't handle SSA_NAME and ICEs
    on it.
    SSA_NAMEs don't ever have TREE_SIDE_EFFECTS set on those, so the following
    patch fixes it by handling it similarly to the tcc_constant case.
    
    2024-01-08  Jakub Jelinek  <jakub@redhat.com>
    
            PR tree-optimization/113228
            * gimplify.cc (recalculate_side_effects): Do nothing for SSA_NAMEs.
    
            * gcc.c-torture/compile/pr113228.c: New test.

Diff:
---
 gcc/gimplify.cc                                |  3 +++
 gcc/testsuite/gcc.c-torture/compile/pr113228.c | 17 +++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index 15b540646c2..4ed7a07cb7f 100644
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -3344,6 +3344,9 @@ recalculate_side_effects (tree t)
       return;
 
     default:
+      if (code == SSA_NAME)
+	/* No side-effects.  */
+	return;
       gcc_unreachable ();
    }
 }
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr113228.c b/gcc/testsuite/gcc.c-torture/compile/pr113228.c
new file mode 100644
index 00000000000..f46018442f9
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr113228.c
@@ -0,0 +1,17 @@
+/* PR tree-optimization/113228 */
+
+int a, b, c, d, i;
+
+void
+foo (void)
+{
+  int k[3] = {};
+  int *l = &a;
+  for (d = 0; c; c--)
+    for (i = 0; i <= 9; i++)
+      {
+	for (b = 1; b <= 4; b++)
+	  k[0] = k[0] == 0;
+	*l |= k[d];
+      }
+}