This is 3rd (and hopefully last) time to fix the order here.
The previous times were r16-5093-g77e10b47f25d05 and r16-4905-g7b9d32aa2ffcb5.
The order before these patches were:
* removal of phi
* propagate constants
* gimplification of expr
* create assignment
* rewrite to undefined
* add stmts to bb
The current order before this patch (and after the other 2):
* gimplification of expr
* removal of phi
* create assignment
* propagate constants
* rewrite to undefined
* add stmts to bb
The correct and new order with this patch we have:
* gimplifcation of expr
* propagate constants
* removal of phi
* create the assignment
* rewrite to undefined
* add stmts to bb
This is because the propagate of the constant will cause a fold_stmt which
requires
the statement in the IR still. The gimplifcation of expr also calls fold_stmt.
Now with the new order the phi is not removed until right before the creation
of the
new assigment so the IR in the basic block is well defined while calling
fold_stmt.
Pushed as obvious after bootstrap/test on x86_64-linux-gnu.
PR tree-optimization/122637
gcc/ChangeLog:
* tree-scalar-evolution.cc (final_value_replacement_loop): Fix order
of gimplification and constant prop.
gcc/testsuite/ChangeLog:
* gcc.dg/torture/pr122637-1.c: New test.
Signed-off-by: Andrew Pinski <[email protected]>
---
gcc/testsuite/gcc.dg/torture/pr122637-1.c | 11 +++++++++++
gcc/tree-scalar-evolution.cc | 10 +++++-----
2 files changed, 16 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/torture/pr122637-1.c
diff --git a/gcc/testsuite/gcc.dg/torture/pr122637-1.c
b/gcc/testsuite/gcc.dg/torture/pr122637-1.c
new file mode 100644
index 00000000000..22d6d2ddec1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr122637-1.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* PR tree-optimization/122637 */
+
+char a[10][3];
+int b;
+void e(short c) {
+ for (; c; c--) {
+ for (int d = 2; d; d--)
+ b = a[d][0] & a[c][d];
+ }
+}
diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc
index 626c201df5e..307628aa631 100644
--- a/gcc/tree-scalar-evolution.cc
+++ b/gcc/tree-scalar-evolution.cc
@@ -3966,6 +3966,11 @@ final_value_replacement_loop (class loop *loop)
gimple_seq stmts;
def = force_gimple_operand (def, &stmts, false, NULL_TREE);
+ /* Propagate constants immediately, but leave an unused initialization
+ around to avoid invalidating the SCEV cache. */
+ if (CONSTANT_CLASS_P (def) && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rslt))
+ replace_uses_by (rslt, def);
+
/* Remove the old phi after the gimplification to make sure the
SSA name is defined by a statement so that fold_stmt during
the gimplification does not crash. */
@@ -3974,11 +3979,6 @@ final_value_replacement_loop (class loop *loop)
gimple_set_location (ass, loc);
gimple_seq_add_stmt (&stmts, ass);
- /* Propagate constants immediately, but leave an unused initialization
- around to avoid invalidating the SCEV cache. */
- if (CONSTANT_CLASS_P (def) && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rslt))
- replace_uses_by (rslt, def);
-
/* If def's type has undefined overflow and there were folded
casts, rewrite all stmts added for def into arithmetics
with defined overflow behavior. */
--
2.43.0
