diff options
| author | Richard Biener <rguenther@suse.de> | 2024-05-27 10:41:02 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2024-05-28 14:35:35 +0200 |
| commit | c08b0d3f7b3539b26031de31d88dea6b94474577 (patch) | |
| tree | 6a39dd8f4b636828d32f683173046cfcf4fd0a4b | |
| parent | 19cc61111120087619b496732b249b48b1fbe27e (diff) | |
| download | gcc-c08b0d3f7b3539b26031de31d88dea6b94474577.zip gcc-c08b0d3f7b3539b26031de31d88dea6b94474577.tar.gz gcc-c08b0d3f7b3539b26031de31d88dea6b94474577.tar.bz2 | |
tree-optimization/115236 - more points-to *ANYTHING = x fixes
The stored-to ANYTHING handling has more holes, uncovered by treating
volatile accesses as ANYTHING. We fail to properly build the
pred and succ graphs, in particular we may not elide direct nodes
from receiving from STOREDANYTHING.
PR tree-optimization/115236
* tree-ssa-structalias.cc (build_pred_graph): Properly
handle *ANYTHING = X.
(build_succ_graph): Likewise. Do not elide direct nodes
from receiving from STOREDANYTHING.
* gcc.dg/pr115236.c: New testcase.
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr115236.c | 12 | ||||
| -rw-r--r-- | gcc/tree-ssa-structalias.cc | 20 |
2 files changed, 26 insertions, 6 deletions
diff --git a/gcc/testsuite/gcc.dg/pr115236.c b/gcc/testsuite/gcc.dg/pr115236.c new file mode 100644 index 0000000..91edfab --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr115236.c @@ -0,0 +1,12 @@ +/* { dg-do run } */ +/* { dg-options "-O -fno-tree-fre" } */ + +int a, *b = &a; +int main() +{ + int *c, *volatile *d = &c; + *d = b; + if (c != &a) + __builtin_abort(); + return 0; +} diff --git a/gcc/tree-ssa-structalias.cc b/gcc/tree-ssa-structalias.cc index 9cec2c6..330e64e 100644 --- a/gcc/tree-ssa-structalias.cc +++ b/gcc/tree-ssa-structalias.cc @@ -1312,7 +1312,12 @@ build_pred_graph (void) { /* *x = y. */ if (rhs.offset == 0 && lhs.offset == 0 && rhs.type == SCALAR) - add_pred_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); + { + if (lhs.var == anything_id) + add_pred_graph_edge (graph, storedanything_id, rhsvar); + else + add_pred_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); + } } else if (rhs.type == DEREF) { @@ -1398,7 +1403,12 @@ build_succ_graph (void) if (lhs.type == DEREF) { if (rhs.offset == 0 && lhs.offset == 0 && rhs.type == SCALAR) - add_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); + { + if (lhs.var == anything_id) + add_graph_edge (graph, storedanything_id, rhsvar); + else + add_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); + } } else if (rhs.type == DEREF) { @@ -1418,13 +1428,11 @@ build_succ_graph (void) } } - /* Add edges from STOREDANYTHING to all non-direct nodes that can - receive pointers. */ + /* Add edges from STOREDANYTHING to all nodes that can receive pointers. */ t = find (storedanything_id); for (i = integer_id + 1; i < FIRST_REF_NODE; ++i) { - if (!bitmap_bit_p (graph->direct_nodes, i) - && get_varinfo (i)->may_have_pointers) + if (get_varinfo (i)->may_have_pointers) add_graph_edge (graph, find (i), t); } |