On Sun, Apr 23, 2023 at 12:13 AM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> This adds diamond shaped form of basic blocks to match_simplify_replacement.
> This is the patch is the start of removing/moving all
> of what minmax_replacement does to match.pd to reduce the code duplication.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
OK.
thanks,
Richard.
> Note phi-opt-{23,24}.c testcase had an incorrect xfail as there should
> have been 2 if still because f4/f5 would not be transformed as -ABS is
> not allowable during early phi-opt.
>
> gcc/ChangeLog:
>
> * tree-ssa-phiopt.cc (match_simplify_replacement): Add new arguments
> and support diamond shaped basic block form.
> (tree_ssa_phiopt_worker): Update call to match_simplify_replacement
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/tree-ssa/phi-opt-23.c: Update testcase.
> * gcc.dg/tree-ssa/phi-opt-24.c: Likewise.
> ---
> gcc/testsuite/gcc.dg/tree-ssa/phi-opt-23.c | 4 +--
> gcc/testsuite/gcc.dg/tree-ssa/phi-opt-24.c | 4 +--
> gcc/tree-ssa-phiopt.cc | 37 ++++++++++++++++++----
> 3 files changed, 35 insertions(+), 10 deletions(-)
>
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-23.c
> b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-23.c
> index ff658cd16a7..86aab955d5e 100644
> --- a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-23.c
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-23.c
> @@ -38,7 +38,7 @@ int f5(int A)
> return -A;
> }
>
> -/* These should be optimized in phiopt1 but is confused by predicts. */
> -/* { dg-final { scan-tree-dump-not "if" "phiopt1" { xfail *-*-* } } } */
> +/* f4 and f5 are not allowed to be optimized in early phi-opt. */
> +/* { dg-final { scan-tree-dump-times "if" 2 "phiopt1" } } */
> /* { dg-final { scan-tree-dump-not "if" "phiopt2" } } */
>
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-24.c
> b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-24.c
> index eb89decb4bf..bd8308efa0e 100644
> --- a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-24.c
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-24.c
> @@ -38,7 +38,7 @@ float f5(float A)
> return -A;
> }
>
> -/* These should be optimized in phiopt1 but is confused by predicts. */
> -/* { dg-final { scan-tree-dump-not "if" "phiopt1" { xfail *-*-* } } } */
> +/* f4 and f5 are not allowed to be optimized in early phi-opt. */
> +/* { dg-final { scan-tree-dump-times "if" 2 "phiopt1" } } */
> /* { dg-final { scan-tree-dump-not "if" "phiopt2" } } */
>
> diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
> index ffd6a4e6f35..757e44692ed 100644
> --- a/gcc/tree-ssa-phiopt.cc
> +++ b/gcc/tree-ssa-phiopt.cc
> @@ -57,8 +57,8 @@ along with GCC; see the file COPYING3. If not see
>
> static bool two_value_replacement (basic_block, basic_block, edge, gphi *,
> tree, tree);
> -static bool match_simplify_replacement (basic_block, basic_block,
> - edge, edge, gphi *, tree, tree, bool);
> +static bool match_simplify_replacement (basic_block, basic_block,
> basic_block,
> + edge, edge, gphi *, tree, tree, bool,
> bool);
> static gphi *factor_out_conditional_conversion (edge, edge, gphi *, tree,
> tree,
> gimple *);
> static int value_replacement (basic_block, basic_block,
> @@ -304,9 +304,8 @@ tree_ssa_phiopt_worker (bool do_store_elim, bool
> do_hoist_loads, bool early_p)
> && !diamond_p
> && two_value_replacement (bb, bb1, e2, phi, arg0, arg1))
> cfgchanged = true;
> - else if (!diamond_p
> - && match_simplify_replacement (bb, bb1, e1, e2, phi,
> - arg0, arg1, early_p))
> + else if (match_simplify_replacement (bb, bb1, bb2, e1, e2, phi,
> + arg0, arg1, early_p, diamond_p))
> cfgchanged = true;
> else if (!early_p
> && !diamond_p
> @@ -1026,8 +1025,10 @@ empty_bb_or_one_feeding_into_p (basic_block bb,
>
> static bool
> match_simplify_replacement (basic_block cond_bb, basic_block middle_bb,
> + basic_block middle_bb_alt,
> edge e0, edge e1, gphi *phi,
> - tree arg0, tree arg1, bool early_p)
> + tree arg0, tree arg1, bool early_p,
> + bool threeway_p)
> {
> gimple *stmt;
> gimple_stmt_iterator gsi;
> @@ -1035,6 +1036,7 @@ match_simplify_replacement (basic_block cond_bb,
> basic_block middle_bb,
> gimple_seq seq = NULL;
> tree result;
> gimple *stmt_to_move = NULL;
> + gimple *stmt_to_move_alt = NULL;
> auto_bitmap inserted_exprs;
>
> /* Special case A ? B : B as this will always simplify to B. */
> @@ -1046,6 +1048,12 @@ match_simplify_replacement (basic_block cond_bb,
> basic_block middle_bb,
> if (!empty_bb_or_one_feeding_into_p (middle_bb, phi, stmt_to_move))
> return false;
>
> + if (threeway_p
> + && middle_bb != middle_bb_alt
> + && !empty_bb_or_one_feeding_into_p (middle_bb_alt, phi,
> + stmt_to_move_alt))
> + return false;
> +
> /* At this point we know we have a GIMPLE_COND with two successors.
> One successor is BB, the other successor is an empty block which
> falls through into BB.
> @@ -1110,6 +1118,23 @@ match_simplify_replacement (basic_block cond_bb,
> basic_block middle_bb,
> reset_flow_sensitive_info (name);
> }
>
> + if (stmt_to_move_alt)
> + {
> + if (dump_file && (dump_flags & TDF_DETAILS))
> + {
> + fprintf (dump_file, "statement un-sinked:\n");
> + print_gimple_stmt (dump_file, stmt_to_move_alt, 0,
> + TDF_VOPS|TDF_MEMSYMS);
> + }
> +
> + tree name = gimple_get_lhs (stmt_to_move_alt);
> + // Mark the name to be renamed if there is one.
> + bitmap_set_bit (inserted_exprs, SSA_NAME_VERSION (name));
> + gimple_stmt_iterator gsi1 = gsi_for_stmt (stmt_to_move_alt);
> + gsi_move_before (&gsi1, &gsi);
> + reset_flow_sensitive_info (name);
> + }
> +
> replace_phi_edge_with_variable (cond_bb, e1, phi, result, inserted_exprs);
>
> /* Add Statistic here even though replace_phi_edge_with_variable already
> --
> 2.39.1
>
