tree-optimization/108825 - checking ICE with unroll-and-jam

The issue is that unroll-and-jam applies RPO VN on the transformed body but
that leaves the IL in "indetermined" state (it returns a TODO to make it
valid again).  But unroll-and-jam then continues to transform another loop and
in using the tree_unroll_loop helper runs into tree_transform_and_unroll_loop
performing IL checking on the whole function.

While the real fix is to elide all such checking I'm only making the
loop-local LC SSA verifier not perform function-wide SSA verification
at this point.

	PR tree-optimization/108825
	* tree-ssa-loop-manip.cc (verify_loop_closed_ssa): For
	loop-local verfication only verify there's no pending SSA
	update.

	* gcc.dg/torture/pr108825.c: New testcase.

diff --git a/gcc/testsuite/gcc.dg/torture/pr108825.c b/gcc/testsuite/gcc.dg/torture/pr108825.c
new file mode 100644 (file)
index 0000000..ada2da8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr108825.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+
+int safe_mul_func_uint8_t_u_u_ui2, g_231, g_277_1, g_568, func_35___trans_tmp_10;
+int g_81[7];
+extern int g_96[];
+char func_35___trans_tmp_11;
+static inline int safe_add_func_int32_t_s_s(int si1, int si2)
+{ return si1 > 647 - si2 ?: si1; }
+void func_35() {
+  for (; g_277_1; g_277_1 += 1) {
+    g_231 = 0;
+    for (; g_231 <= 6; g_231 += 1) {
+      func_35___trans_tmp_10 =
+          safe_add_func_int32_t_s_s(g_81[g_231], g_568 || g_96[1]);
+      func_35___trans_tmp_11 =
+          func_35___trans_tmp_10 * safe_mul_func_uint8_t_u_u_ui2;
+      g_81[g_231] = func_35___trans_tmp_11;
+    }
+  }
+}

diff --git a/gcc/tree-ssa-loop-manip.cc b/gcc/tree-ssa-loop-manip.cc
index 14fe65f..09acc1c 100644 (file)
--- a/gcc/tree-ssa-loop-manip.cc
+++ b/gcc/tree-ssa-loop-manip.cc
@@ -681,15 +681,15 @@ verify_loop_closed_ssa (bool verify_ssa_p, class loop *loop)
   if (number_of_loops (cfun) <= 1)
     return;
 
-  if (verify_ssa_p)
-    verify_ssa (false, true);
-
   timevar_push (TV_VERIFY_LOOP_CLOSED);
 
   if (loop == NULL)
     {
       basic_block bb;
 
+      if (verify_ssa_p)
+       verify_ssa (false, true);
+
       FOR_EACH_BB_FN (bb, cfun)
        if (bb->loop_father && bb->loop_father->num > 0)
          check_loop_closed_ssa_bb (bb);
@@ -698,6 +698,11 @@ verify_loop_closed_ssa (bool verify_ssa_p, class loop *loop)
     {
       basic_block *bbs = get_loop_body (loop);
 
+      /* We do not have loop-local SSA verification so just
+        check there's no update queued.  */
+      if (verify_ssa_p)
+       gcc_assert (!need_ssa_update_p (cfun));
+
       for (unsigned i = 0; i < loop->num_nodes; ++i)
        check_loop_closed_ssa_bb (bbs[i]);