| Message ID | 20230424213011.528181-3-apinski@marvell.com |
|---|---|
| State | New |
| Headers | show |
| Series | Some more phiopt cleanups and double minmax to match | expand |
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 >
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: