On Mon, Apr 24, 2023 at 11:34 PM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> Now that store elimination and phiopt does not
> share outer code, we can move tree_ssa_phiopt_worker
> directly into pass_phiopt::execute and remove
> many declarations (prototypes) from the file.
OK.
> gcc/ChangeLog:
>
> * tree-ssa-phiopt.cc (two_value_replacement): Remove
> prototype.
> (match_simplify_replacement): Likewise.
> (factor_out_conditional_conversion): Likewise.
> (value_replacement): Likewise.
> (minmax_replacement): Likewise.
> (spaceship_replacement): Likewise.
> (cond_removal_in_builtin_zero_pattern): Likewise.
> (hoist_adjacent_loads): Likewise.
> (tree_ssa_phiopt_worker): Move into ...
> (pass_phiopt::execute): this.
> ---
> gcc/tree-ssa-phiopt.cc | 385 +++++++++++++++++++----------------------
> 1 file changed, 181 insertions(+), 204 deletions(-)
>
> diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
> index 7f47b32576b..d232fd9b551 100644
> --- a/gcc/tree-ssa-phiopt.cc
> +++ b/gcc/tree-ssa-phiopt.cc
> @@ -55,27 +55,10 @@ along with GCC; see the file COPYING3. If not see
> #include "tree-ssa-propagate.h"
> #include "tree-ssa-dce.h"
>
> -static bool two_value_replacement (basic_block, basic_block, edge, gphi *,
> - tree, tree);
> -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,
> - edge, edge, gphi *, tree, tree);
> -static bool minmax_replacement (basic_block, basic_block, basic_block,
> - edge, edge, gphi *, tree, tree, bool);
> -static bool spaceship_replacement (basic_block, basic_block,
> - edge, edge, gphi *, tree, tree);
> -static bool cond_removal_in_builtin_zero_pattern (basic_block, basic_block,
> - edge, edge, gphi *,
> - tree, tree);
> static bool cond_store_replacement (basic_block, basic_block, edge, edge,
> hash_set<tree> *);
> static bool cond_if_else_store_replacement (basic_block, basic_block,
> basic_block);
> static hash_set<tree> * get_non_trapping ();
> -static void hoist_adjacent_loads (basic_block, basic_block,
> - basic_block, basic_block);
>
> /* Return the singleton PHI in the SEQ of PHIs for edges E0 and E1. */
>
> @@ -104,188 +87,6 @@ single_non_singleton_phi_for_edges (gimple_seq seq, edge
> e0, edge e1)
> return phi;
> }
>
> -/* The core routine of phi optimizations.
> - DO_HOIST_LOADS is true when we want to hoist adjacent loads out
> - of diamond control flow patterns, false otherwise. */
> -static unsigned int
> -tree_ssa_phiopt_worker (bool do_hoist_loads, bool early_p)
> -{
> - basic_block bb;
> - basic_block *bb_order;
> - unsigned n, i;
> - bool cfgchanged = false;
> -
> - calculate_dominance_info (CDI_DOMINATORS);
> -
> - /* Search every basic block for COND_EXPR we may be able to optimize.
> -
> - We walk the blocks in order that guarantees that a block with
> - a single predecessor is processed before the predecessor.
> - This ensures that we collapse inner ifs before visiting the
> - outer ones, and also that we do not try to visit a removed
> - block. */
> - bb_order = single_pred_before_succ_order ();
> - n = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS;
> -
> - for (i = 0; i < n; i++)
> - {
> - gphi *phi;
> - basic_block bb1, bb2;
> - edge e1, e2;
> - tree arg0, arg1;
> - bool diamond_p = false;
> -
> - bb = bb_order[i];
> -
> - /* Check to see if the last statement is a GIMPLE_COND. */
> - gcond *cond_stmt = safe_dyn_cast <gcond *> (*gsi_last_bb (bb));
> - if (!cond_stmt)
> - continue;
> -
> - e1 = EDGE_SUCC (bb, 0);
> - bb1 = e1->dest;
> - e2 = EDGE_SUCC (bb, 1);
> - bb2 = e2->dest;
> -
> - /* We cannot do the optimization on abnormal edges. */
> - if ((e1->flags & EDGE_ABNORMAL) != 0
> - || (e2->flags & EDGE_ABNORMAL) != 0)
> - continue;
> -
> - /* If either bb1's succ or bb2 or bb2's succ is non NULL. */
> - if (EDGE_COUNT (bb1->succs) == 0
> - || EDGE_COUNT (bb2->succs) == 0)
> - continue;
> -
> - /* Find the bb which is the fall through to the other. */
> - if (EDGE_SUCC (bb1, 0)->dest == bb2)
> - ;
> - else if (EDGE_SUCC (bb2, 0)->dest == bb1)
> - {
> - std::swap (bb1, bb2);
> - std::swap (e1, e2);
> - }
> - else if (EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest
> - && single_succ_p (bb2))
> - {
> - diamond_p = true;
> - e2 = EDGE_SUCC (bb2, 0);
> - /* Make sure bb2 is just a fall through. */
> - if ((e2->flags & EDGE_FALLTHRU) == 0)
> - continue;
> - }
> - else
> - continue;
> -
> - e1 = EDGE_SUCC (bb1, 0);
> -
> - /* Make sure that bb1 is just a fall through. */
> - if (!single_succ_p (bb1)
> - || (e1->flags & EDGE_FALLTHRU) == 0)
> - continue;
> -
> - if (diamond_p)
> - {
> - basic_block bb3 = e1->dest;
> -
> - if (!single_pred_p (bb1)
> - || !single_pred_p (bb2))
> - continue;
> -
> - if (do_hoist_loads
> - && !FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt)))
> - && EDGE_COUNT (bb->succs) == 2
> - && EDGE_COUNT (bb3->preds) == 2
> - /* If one edge or the other is dominant, a conditional move
> - is likely to perform worse than the well-predicted branch.
> */
> - && !predictable_edge_p (EDGE_SUCC (bb, 0))
> - && !predictable_edge_p (EDGE_SUCC (bb, 1)))
> - hoist_adjacent_loads (bb, bb1, bb2, bb3);
> - }
> -
> - gimple_stmt_iterator gsi;
> - bool candorest = true;
> -
> - /* Check that we're looking for nested phis. */
> - basic_block merge = diamond_p ? EDGE_SUCC (bb2, 0)->dest : bb2;
> - gimple_seq phis = phi_nodes (merge);
> -
> - /* Value replacement can work with more than one PHI
> - so try that first. */
> - if (!early_p && !diamond_p)
> - for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
> - {
> - phi = as_a <gphi *> (gsi_stmt (gsi));
> - arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> - arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> - if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2)
> - {
> - candorest = false;
> - cfgchanged = true;
> - break;
> - }
> - }
> -
> - if (!candorest)
> - continue;
> -
> - phi = single_non_singleton_phi_for_edges (phis, e1, e2);
> - if (!phi)
> - continue;
> -
> - arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> - arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> -
> - /* Something is wrong if we cannot find the arguments in the PHI
> - node. */
> - gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE);
> -
> - gphi *newphi;
> - if (single_pred_p (bb1)
> - && !diamond_p
> - && (newphi = factor_out_conditional_conversion (e1, e2, phi,
> - arg0, arg1,
> - cond_stmt)))
> - {
> - phi = newphi;
> - /* factor_out_conditional_conversion may create a new PHI in
> - BB2 and eliminate an existing PHI in BB2. Recompute values
> - that may be affected by that change. */
> - arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> - arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> - gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE);
> - }
> -
> - /* Do the replacement of conditional if it can be done. */
> - if (!early_p
> - && !diamond_p
> - && two_value_replacement (bb, bb1, e2, phi, arg0, arg1))
> - cfgchanged = true;
> - 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
> - && single_pred_p (bb1)
> - && cond_removal_in_builtin_zero_pattern (bb, bb1, e1, e2,
> - phi, arg0, arg1))
> - cfgchanged = true;
> - else if (minmax_replacement (bb, bb1, bb2, e1, e2, phi, arg0, arg1,
> - diamond_p))
> - cfgchanged = true;
> - else if (single_pred_p (bb1)
> - && !diamond_p
> - && spaceship_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
> - cfgchanged = true;
> - }
> -
> - free (bb_order);
> -
> - if (cfgchanged)
> - return TODO_cleanup_cfg;
> - return 0;
> -}
> -
> /* The core routine of conditional store replacement. */
> static unsigned int
> store_elim_worker (void)
> @@ -4328,11 +4129,7 @@ public:
> early_p = param;
> }
> bool gate (function *) final override { return flag_ssa_phiopt; }
> - unsigned int execute (function *) final override
> - {
> - return tree_ssa_phiopt_worker (!early_p ? gate_hoist_loads () : false,
> - early_p);
> - }
> + unsigned int execute (function *) final override;
>
> private:
> bool early_p;
> @@ -4346,6 +4143,186 @@ make_pass_phiopt (gcc::context *ctxt)
> return new pass_phiopt (ctxt);
> }
>
> +unsigned int
> +pass_phiopt::execute (function *)
> +{
> + bool do_hoist_loads = !early_p ? gate_hoist_loads () : false;
> + basic_block bb;
> + basic_block *bb_order;
> + unsigned n, i;
> + bool cfgchanged = false;
> +
> + calculate_dominance_info (CDI_DOMINATORS);
> +
> + /* Search every basic block for COND_EXPR we may be able to optimize.
> +
> + We walk the blocks in order that guarantees that a block with
> + a single predecessor is processed before the predecessor.
> + This ensures that we collapse inner ifs before visiting the
> + outer ones, and also that we do not try to visit a removed
> + block. */
> + bb_order = single_pred_before_succ_order ();
> + n = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS;
> +
> + for (i = 0; i < n; i++)
> + {
> + gphi *phi;
> + basic_block bb1, bb2;
> + edge e1, e2;
> + tree arg0, arg1;
> + bool diamond_p = false;
> +
> + bb = bb_order[i];
> +
> + /* Check to see if the last statement is a GIMPLE_COND. */
> + gcond *cond_stmt = safe_dyn_cast <gcond *> (*gsi_last_bb (bb));
> + if (!cond_stmt)
> + continue;
> +
> + e1 = EDGE_SUCC (bb, 0);
> + bb1 = e1->dest;
> + e2 = EDGE_SUCC (bb, 1);
> + bb2 = e2->dest;
> +
> + /* We cannot do the optimization on abnormal edges. */
> + if ((e1->flags & EDGE_ABNORMAL) != 0
> + || (e2->flags & EDGE_ABNORMAL) != 0)
> + continue;
> +
> + /* If either bb1's succ or bb2 or bb2's succ is non NULL. */
> + if (EDGE_COUNT (bb1->succs) == 0
> + || EDGE_COUNT (bb2->succs) == 0)
> + continue;
> +
> + /* Find the bb which is the fall through to the other. */
> + if (EDGE_SUCC (bb1, 0)->dest == bb2)
> + ;
> + else if (EDGE_SUCC (bb2, 0)->dest == bb1)
> + {
> + std::swap (bb1, bb2);
> + std::swap (e1, e2);
> + }
> + else if (EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest
> + && single_succ_p (bb2))
> + {
> + diamond_p = true;
> + e2 = EDGE_SUCC (bb2, 0);
> + /* Make sure bb2 is just a fall through. */
> + if ((e2->flags & EDGE_FALLTHRU) == 0)
> + continue;
> + }
> + else
> + continue;
> +
> + e1 = EDGE_SUCC (bb1, 0);
> +
> + /* Make sure that bb1 is just a fall through. */
> + if (!single_succ_p (bb1)
> + || (e1->flags & EDGE_FALLTHRU) == 0)
> + continue;
> +
> + if (diamond_p)
> + {
> + basic_block bb3 = e1->dest;
> +
> + if (!single_pred_p (bb1)
> + || !single_pred_p (bb2))
> + continue;
> +
> + if (do_hoist_loads
> + && !FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt)))
> + && EDGE_COUNT (bb->succs) == 2
> + && EDGE_COUNT (bb3->preds) == 2
> + /* If one edge or the other is dominant, a conditional move
> + is likely to perform worse than the well-predicted branch.
> */
> + && !predictable_edge_p (EDGE_SUCC (bb, 0))
> + && !predictable_edge_p (EDGE_SUCC (bb, 1)))
> + hoist_adjacent_loads (bb, bb1, bb2, bb3);
> + }
> +
> + gimple_stmt_iterator gsi;
> + bool candorest = true;
> +
> + /* Check that we're looking for nested phis. */
> + basic_block merge = diamond_p ? EDGE_SUCC (bb2, 0)->dest : bb2;
> + gimple_seq phis = phi_nodes (merge);
> +
> + /* Value replacement can work with more than one PHI
> + so try that first. */
> + if (!early_p && !diamond_p)
> + for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
> + {
> + phi = as_a <gphi *> (gsi_stmt (gsi));
> + arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> + arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> + if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2)
> + {
> + candorest = false;
> + cfgchanged = true;
> + break;
> + }
> + }
> +
> + if (!candorest)
> + continue;
> +
> + phi = single_non_singleton_phi_for_edges (phis, e1, e2);
> + if (!phi)
> + continue;
> +
> + arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> + arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> +
> + /* Something is wrong if we cannot find the arguments in the PHI
> + node. */
> + gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE);
> +
> + gphi *newphi;
> + if (single_pred_p (bb1)
> + && !diamond_p
> + && (newphi = factor_out_conditional_conversion (e1, e2, phi,
> + arg0, arg1,
> + cond_stmt)))
> + {
> + phi = newphi;
> + /* factor_out_conditional_conversion may create a new PHI in
> + BB2 and eliminate an existing PHI in BB2. Recompute values
> + that may be affected by that change. */
> + arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
> + arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
> + gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE);
> + }
> +
> + /* Do the replacement of conditional if it can be done. */
> + if (!early_p
> + && !diamond_p
> + && two_value_replacement (bb, bb1, e2, phi, arg0, arg1))
> + cfgchanged = true;
> + 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
> + && single_pred_p (bb1)
> + && cond_removal_in_builtin_zero_pattern (bb, bb1, e1, e2,
> + phi, arg0, arg1))
> + cfgchanged = true;
> + else if (minmax_replacement (bb, bb1, bb2, e1, e2, phi, arg0, arg1,
> + diamond_p))
> + cfgchanged = true;
> + else if (single_pred_p (bb1)
> + && !diamond_p
> + && spaceship_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
> + cfgchanged = true;
> + }
> +
> + free (bb_order);
> +
> + if (cfgchanged)
> + return TODO_cleanup_cfg;
> + return 0;
> +}
> +
> /* This pass tries to transform conditional stores into unconditional
> ones, enabling further simplifications with the simpler then and else
> blocks. In particular it replaces this:
> --
> 2.39.1
>
