This patch adds a check in match_simplify_replacement to make sure the middlebb
does not have any phi-nodes as we don't currently move those.
This was just a thinko from before.
Ok? Bootstrapped and tested on x86_64-linux-gnu with no regressions?
PR tree-optimization/108582
gcc/ChangeLog:
* tree-ssa-phiopt.cc (match_simplify_replacement): Add check
for middlebb to have no phi nodes.
gcc/testsuite/ChangeLog:
* gcc.dg/pr108582-1.c: New test.
---
gcc/testsuite/gcc.dg/pr108582-1.c | 58 +++++++++++++++++++++++++++++++
gcc/tree-ssa-phiopt.cc | 5 +++
2 files changed, 63 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/pr108582-1.c
diff --git a/gcc/testsuite/gcc.dg/pr108582-1.c
b/gcc/testsuite/gcc.dg/pr108582-1.c
new file mode 100644
index 00000000000..88c2de369ad
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr108582-1.c
@@ -0,0 +1,58 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -fno-tree-ccp -fno-tree-dce" } */
+
+/*
+ PHI-OPT via match_simplify_replacement used to transform:
+ if (_25 != 0)
+ goto <bb 8>; [25.00%]
+ else
+ goto <bb 9>; [75.00%]
+
+ <bb 8> [local count: 11649864]:
+ # iftmp.5_13 = PHI <2(7)>
+ k_22 = k_11 | iftmp.5_13;
+
+ <bb 9> [local count: 105655256]:
+ # g_9 = PHI <1(2), 0(8), g_8(7)>
+ # k_12 = PHI <k_20(D)(2), k_22(8), k_11(7)>
+
+into:
+
+ _15 = (int) _25;
+ _28 = -_15;
+ _4 = _13 & _28;
+ _6 = _4 | k_11;
+
+ <bb 8> [local count: 105655256]:
+ # g_9 = PHI <1(2), g_8(7)>
+ # k_12 = PHI <k_20(D)(2), _6(7)>
+
+Removing the phi-node/assignment of _13.
+
+ */
+
+int a, c, d, e, f;
+char b;
+int main() {
+ int g = 1;
+ char h[1] = {0};
+ while (a) {
+ if (f) {
+ b = 0;
+ if (d)
+ continue;
+ }
+ if (a < 1) {
+ g = 0;
+ goto L;
+ }
+ }
+ while (c) {
+ char *j = h;
+ int k;
+ L:
+ if (e && !g)
+ k |= 2 | (*j < 0);
+ }
+ return 0;
+}
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index c3a889dc593..a7ab6ce4ad9 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -1002,6 +1002,11 @@ match_simplify_replacement (basic_block cond_bb,
basic_block middle_bb,
if (!single_pred_p (middle_bb))
return false;
+ /* The middle bb cannot have phi nodes as we don't
+ move those assignments yet. */
+ if (!gimple_seq_empty_p (phi_nodes (middle_bb)))
+ return false;
+
stmt_to_move = last_and_only_stmt (middle_bb);
if (!stmt_to_move)
return false;
--
2.31.1
