Predictive commoning happens to re-use SSA names it released while
there are still uses of them (oops), confusing the hell out of
other code (expected). Fixed thus.
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Richard.
2015-02-16 Richard Biener <rguent...@suse.de>
PR tree-optimization/63593
PR tree-optimization/65063
* tree-predcom.c (execute_pred_commoning_chain): Delay removing
stmts and releasing SSA names until...
(execute_pred_commoning): ... after processing all chains.
* gcc.dg/pr63593.c: New testcase.
* gcc.dg/pr65063.c: Likewise.
Index: gcc/tree-predcom.c
===================================================================
--- gcc/tree-predcom.c (revision 220731)
+++ gcc/tree-predcom.c (working copy)
@@ -1745,9 +1745,8 @@ execute_pred_commoning_chain (struct loo
if (chain->combined)
{
/* For combined chains, just remove the statements that are used to
- compute the values of the expression (except for the root one). */
- for (i = 1; chain->refs.iterate (i, &a); i++)
- remove_stmt (a->stmt);
+ compute the values of the expression (except for the root one).
+ We delay this until after all chains are processed. */
}
else
{
@@ -1811,6 +1810,21 @@ execute_pred_commoning (struct loop *loo
execute_pred_commoning_chain (loop, chain, tmp_vars);
}
+ FOR_EACH_VEC_ELT (chains, i, chain)
+ {
+ if (chain->type == CT_INVARIANT)
+ ;
+ else if (chain->combined)
+ {
+ /* For combined chains, just remove the statements that are used to
+ compute the values of the expression (except for the root one). */
+ dref a;
+ unsigned j;
+ for (j = 1; chain->refs.iterate (j, &a); j++)
+ remove_stmt (a->stmt);
+ }
+ }
+
update_ssa (TODO_update_ssa_only_virtuals);
}
Index: gcc/testsuite/gcc.dg/pr63593.c
===================================================================
--- gcc/testsuite/gcc.dg/pr63593.c (revision 0)
+++ gcc/testsuite/gcc.dg/pr63593.c (working copy)
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -fno-tree-vectorize" } */
+
+int in[2 * 4][4];
+int out[4];
+
+void
+foo (void)
+{
+ int sum;
+ int i, j, k;
+ for (k = 0; k < 4; k++)
+ {
+ sum = 1;
+ for (j = 0; j < 4; j++)
+ for (i = 0; i < 4; i++)
+ sum *= in[i + k][j];
+ out[k] = sum;
+ }
+}
Index: gcc/testsuite/gcc.dg/pr65063.c
===================================================================
--- gcc/testsuite/gcc.dg/pr65063.c (revision 0)
+++ gcc/testsuite/gcc.dg/pr65063.c (working copy)
@@ -0,0 +1,33 @@
+/* { dg-do run } */
+/* { dg-options "-O3 -fno-tree-loop-ivcanon -fno-tree-vectorize" } */
+
+static int in[8][4];
+static int out[4];
+static const int check_result[] = {0, 16, 256, 4096};
+
+static inline void foo ()
+{
+ int sum;
+ int i, j, k;
+ for (k = 0; k < 4; k++)
+ {
+ sum = 1;
+ for (j = 0; j < 4; j++)
+ for (i = 0; i < 4; i++)
+ sum *= in[i + k][j];
+ out[k] = sum;
+ }
+}
+
+int main ()
+{
+ int i, j, k;
+ for (i = 0; i < 8; i++)
+ for (j = 0; j < 4; j++)
+ in[i][j] = (i + 2) / 3;
+ foo ();
+ for (k = 0; k < 4; k++)
+ if (out[k] != check_result[k])
+ __builtin_abort ();
+ return 0;
+}
