On November 12, 2021 8:46:25 PM GMT+01:00, Aldy Hernandez via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>PHIs must be resolved first while solving ranges in a block,
>regardless of where they appear in the import bitmap. We went through
>a similar exercise for the relational code, but missed these.
Must not all stmts be resolved in program order (for optimality at least)?
>Tested on x86-64 & ppc64le Linux.
>
>gcc/ChangeLog:
>
> PR tree-optimization/103202
> * gimple-range-path.cc
> (path_range_query::compute_ranges_in_block): Solve PHI imports first.
>---
> gcc/gimple-range-path.cc | 15 +++++++++++++--
> 1 file changed, 13 insertions(+), 2 deletions(-)
>
>diff --git a/gcc/gimple-range-path.cc b/gcc/gimple-range-path.cc
>index b9aceaf2565..71b290434cb 100644
>--- a/gcc/gimple-range-path.cc
>+++ b/gcc/gimple-range-path.cc
>@@ -365,12 +365,23 @@ path_range_query::compute_ranges_in_block (basic_block
>bb)
> clear_cache (name);
> }
>
>- // Solve imports defined in this block.
>+ // Solve imports defined in this block, starting with the PHIs...
>+ for (gphi_iterator iter = gsi_start_phis (bb); !gsi_end_p (iter);
>+ gsi_next (&iter))
>+ {
>+ gphi *phi = iter.phi ();
>+ tree name = gimple_phi_result (phi);
>+
>+ if (import_p (name) && range_defined_in_block (r, name, bb))
>+ set_cache (r, name);
>+ }
>+ // ...and then the rest of the imports.
> EXECUTE_IF_SET_IN_BITMAP (m_imports, 0, i, bi)
> {
> tree name = ssa_name (i);
>
>- if (range_defined_in_block (r, name, bb))
>+ if (gimple_code (SSA_NAME_DEF_STMT (name)) != GIMPLE_PHI
>+ && range_defined_in_block (r, name, bb))
> set_cache (r, name);
> }
>
