[COMMITTED] path solver: Prefer range_of_expr instead of range_on_edge.
Commit Message
The range_of_expr method provides better caching than range_on_edge.
If we have a statement, we can just it and avoid the range_on_edge
dance. Plus we can use all the range_of_expr fanciness.
Tested on x86-64 and ppc64le Linux with the usual regstrap. I also
verified that the before and after number of threads was the same or
greater in a suite of .ii files from a bootstrap.
gcc/ChangeLog:
PR tree-optimization/102943
* gimple-range-path.cc (path_range_query::range_on_path_entry):
Prefer range_of_expr unless there are no statements in the BB.
---
gcc/gimple-range-path.cc | 18 ++++++++++++++++--
1 file changed, 16 insertions(+), 2 deletions(-)
@@ -135,10 +135,24 @@ void
path_range_query::range_on_path_entry (irange &r, tree name)
{
gcc_checking_assert (defined_outside_path (name));
- int_range_max tmp;
basic_block entry = entry_bb ();
- bool changed = false;
+ // Prefer to use range_of_expr if we have a statement to look at,
+ // since it has better caching than range_on_edge.
+ gimple *last = last_stmt (entry);
+ if (last)
+ {
+ if (m_ranger.range_of_expr (r, name, last))
+ return;
+ gcc_unreachable ();
+ }
+
+ // If we have no statement, look at all the incoming ranges to the
+ // block. This can happen when we're querying a block with only an
+ // outgoing edge (no statement but the fall through edge), but for
+ // which we can determine a range on entry to the block.
+ int_range_max tmp;
+ bool changed = false;
r.set_undefined ();
for (unsigned i = 0; i < EDGE_COUNT (entry->preds); ++i)
{