| Message ID | 20240901040618.1308809-1-quic_apinski@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | slsr: Use simple_dce_from_worklist in SLSR [PR116554] | expand |
> Am 01.09.2024 um 06:07 schrieb Andrew Pinski <quic_apinski@quicinc.com>: > > While working on a phiopt patch, it was noticed that > SLSR would leave around some unused ssa names. Let's > add simple_dce_from_worklist usage to SLSR to remove > the dead statements. This should give a small improvemnent > for passes afterwards. > > Boostrapped and tested on x86_64. Ok Richard > gcc/ChangeLog: > > PR tree-optimization/116554 > * gimple-ssa-strength-reduction.cc: Include tree-ssa-dce.h. > (replace_mult_candidate): Add sdce_worklist argument, mark > the rhs1/rhs2 for maybe dceing. > (replace_unconditional_candidate): Add sdce_worklist argument, > Update call to replace_mult_candidate. > (replace_conditional_candidate): Add sdce_worklist argument, > update call to replace_mult_candidate. > (replace_uncond_cands_and_profitable_phis): Add sdce_worklist argument, > update call to replace_conditional_candidate, > replace_unconditional_candidate, and replace_uncond_cands_and_profitable_phis. > (replace_one_candidate): Add sdce_worklist argument, mark > the orig_rhs1/orig_rhs2 for maybe dceing. > (replace_profitable_candidates): Add sdce_worklist argument, > update call to replace_one_candidate and replace_profitable_candidates. > (analyze_candidates_and_replace): Call simple_dce_from_worklist and > update calls to replace_profitable_candidates, and > replace_uncond_cands_and_profitable_phis. > > Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com> > --- > gcc/gimple-ssa-strength-reduction.cc | 59 +++++++++++++++++++--------- > 1 file changed, 41 insertions(+), 18 deletions(-) > > diff --git a/gcc/gimple-ssa-strength-reduction.cc b/gcc/gimple-ssa-strength-reduction.cc > index 1cb3625c7eb..39cd9339c77 100644 > --- a/gcc/gimple-ssa-strength-reduction.cc > +++ b/gcc/gimple-ssa-strength-reduction.cc > @@ -56,6 +56,7 @@ along with GCC; see the file COPYING3. If not see > #include "tree-affine.h" > #include "tree-eh.h" > #include "builtins.h" > +#include "tree-ssa-dce.h" > > /* Information about a strength reduction candidate. Each statement > in the candidate table represents an expression of one of the > @@ -2126,7 +2127,8 @@ cand_already_replaced (slsr_cand_t c) > replace_conditional_candidate. */ > > static void > -replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) > +replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump, > + auto_bitmap &sdce_worklist) > { > tree target_type = TREE_TYPE (gimple_assign_lhs (c->cand_stmt)); > enum tree_code cand_code = gimple_assign_rhs_code (c->cand_stmt); > @@ -2193,6 +2195,11 @@ replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) > if (cand_code != NEGATE_EXPR) { > rhs1 = gimple_assign_rhs1 (c->cand_stmt); > rhs2 = gimple_assign_rhs2 (c->cand_stmt); > + /* Mark the 2 original rhs for maybe DCEing. */ > + if (TREE_CODE (rhs1) == SSA_NAME) > + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (rhs1)); > + if (TREE_CODE (rhs2) == SSA_NAME) > + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (rhs2)); > } > if (cand_code != NEGATE_EXPR > && ((operand_equal_p (rhs1, basis_name, 0) > @@ -2237,7 +2244,7 @@ replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) > folded value ((i - i') * S) is referred to here as the "bump." */ > > static void > -replace_unconditional_candidate (slsr_cand_t c) > +replace_unconditional_candidate (slsr_cand_t c, auto_bitmap &sdce_worklist) > { > slsr_cand_t basis; > > @@ -2247,7 +2254,8 @@ replace_unconditional_candidate (slsr_cand_t c) > basis = lookup_cand (c->basis); > offset_int bump = cand_increment (c) * wi::to_offset (c->stride); > > - replace_mult_candidate (c, gimple_assign_lhs (basis->cand_stmt), bump); > + replace_mult_candidate (c, gimple_assign_lhs (basis->cand_stmt), bump, > + sdce_worklist); > } > > /* Return the index in the increment vector of the given INCREMENT, > @@ -2507,7 +2515,8 @@ create_phi_basis (slsr_cand_t c, gimple *from_phi, tree basis_name, > basis. */ > > static void > -replace_conditional_candidate (slsr_cand_t c) > +replace_conditional_candidate (slsr_cand_t c, auto_bitmap &sdce_worklist) > + > { > tree basis_name, name; > slsr_cand_t basis; > @@ -2527,7 +2536,7 @@ replace_conditional_candidate (slsr_cand_t c) > /* Replace C with an add of the new basis phi and a constant. */ > offset_int bump = c->index * wi::to_offset (c->stride); > > - replace_mult_candidate (c, name, bump); > + replace_mult_candidate (c, name, bump, sdce_worklist); > } > > /* Recursive helper function for phi_add_costs. SPREAD is a measure of > @@ -2608,7 +2617,8 @@ phi_add_costs (gimple *phi, slsr_cand_t c, int one_add_cost) > so, replace the candidate and introduce the compensation code. */ > > static void > -replace_uncond_cands_and_profitable_phis (slsr_cand_t c) > +replace_uncond_cands_and_profitable_phis (slsr_cand_t c, > + auto_bitmap &sdce_worklist) > { > if (phi_dependent_cand_p (c)) > { > @@ -2643,17 +2653,19 @@ replace_uncond_cands_and_profitable_phis (slsr_cand_t c) > } > > if (cost <= COST_NEUTRAL) > - replace_conditional_candidate (c); > + replace_conditional_candidate (c, sdce_worklist); > } > } > else > - replace_unconditional_candidate (c); > + replace_unconditional_candidate (c, sdce_worklist); > > if (c->sibling) > - replace_uncond_cands_and_profitable_phis (lookup_cand (c->sibling)); > + replace_uncond_cands_and_profitable_phis (lookup_cand (c->sibling), > + sdce_worklist); > > if (c->dependent) > - replace_uncond_cands_and_profitable_phis (lookup_cand (c->dependent)); > + replace_uncond_cands_and_profitable_phis (lookup_cand (c->dependent), > + sdce_worklist); > } > > /* Count the number of candidates in the tree rooted at C that have > @@ -3675,7 +3687,8 @@ replace_rhs_if_not_dup (enum tree_code new_code, tree new_rhs1, tree new_rhs2, > is the rhs1 to use in creating the add/subtract. */ > > static void > -replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) > +replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name, > + auto_bitmap &sdce_worklist) > { > gimple *stmt_to_print = NULL; > tree orig_rhs1, orig_rhs2; > @@ -3693,6 +3706,12 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) > if (!orig_rhs2) > return; > > + /* Mark the 2 original rhs for maybe DCEing. */ > + if (TREE_CODE (orig_rhs1) == SSA_NAME) > + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (orig_rhs1)); > + if (TREE_CODE (orig_rhs2) == SSA_NAME) > + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (orig_rhs2)); > + > if (dump_file && (dump_flags & TDF_DETAILS)) > { > fputs ("Replacing: ", dump_file); > @@ -3835,7 +3854,7 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) > an increment if such has been shown to be profitable. */ > > static void > -replace_profitable_candidates (slsr_cand_t c) > +replace_profitable_candidates (slsr_cand_t c, auto_bitmap &sdce_worklist) > { > if (!cand_already_replaced (c)) > { > @@ -3872,23 +3891,23 @@ replace_profitable_candidates (slsr_cand_t c) > > /* Replace C with an add of the new basis phi and the > increment. */ > - replace_one_candidate (c, i, name); > + replace_one_candidate (c, i, name, sdce_worklist); > } > } > else > { > slsr_cand_t basis = lookup_cand (c->basis); > tree basis_name = gimple_assign_lhs (basis->cand_stmt); > - replace_one_candidate (c, i, basis_name); > + replace_one_candidate (c, i, basis_name, sdce_worklist); > } > } > } > > if (c->sibling) > - replace_profitable_candidates (lookup_cand (c->sibling)); > + replace_profitable_candidates (lookup_cand (c->sibling), sdce_worklist); > > if (c->dependent) > - replace_profitable_candidates (lookup_cand (c->dependent)); > + replace_profitable_candidates (lookup_cand (c->dependent), sdce_worklist); > } > > /* Analyze costs of related candidates in the candidate vector, > @@ -3899,6 +3918,7 @@ analyze_candidates_and_replace (void) > { > unsigned i; > slsr_cand_t c; > + auto_bitmap simple_dce_worklist; > > /* Each candidate that has a null basis and a non-null > dependent is the root of a tree of related statements. > @@ -3932,7 +3952,8 @@ analyze_candidates_and_replace (void) > compensation code it requires is offset by the strength > reduction savings. */ > else if (TREE_CODE (c->stride) == INTEGER_CST) > - replace_uncond_cands_and_profitable_phis (first_dep); > + replace_uncond_cands_and_profitable_phis (first_dep, > + simple_dce_worklist); > > /* When the stride is an SSA name, it may still be profitable > to replace some or all of the dependent candidates, depending > @@ -3969,7 +3990,7 @@ analyze_candidates_and_replace (void) > dump_incr_vec (); > > /* Perform the replacements. */ > - replace_profitable_candidates (first_dep); > + replace_profitable_candidates (first_dep, simple_dce_worklist); > free (incr_vec); > } > } > @@ -3977,6 +3998,8 @@ analyze_candidates_and_replace (void) > /* For conditional candidates, we may have uncommitted insertions > on edges to clean up. */ > gsi_commit_edge_inserts (); > + > + simple_dce_from_worklist (simple_dce_worklist); > } > > namespace { > -- > 2.43.0 >
diff --git a/gcc/gimple-ssa-strength-reduction.cc b/gcc/gimple-ssa-strength-reduction.cc index 1cb3625c7eb..39cd9339c77 100644 --- a/gcc/gimple-ssa-strength-reduction.cc +++ b/gcc/gimple-ssa-strength-reduction.cc @@ -56,6 +56,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-affine.h" #include "tree-eh.h" #include "builtins.h" +#include "tree-ssa-dce.h" /* Information about a strength reduction candidate. Each statement in the candidate table represents an expression of one of the @@ -2126,7 +2127,8 @@ cand_already_replaced (slsr_cand_t c) replace_conditional_candidate. */ static void -replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) +replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump, + auto_bitmap &sdce_worklist) { tree target_type = TREE_TYPE (gimple_assign_lhs (c->cand_stmt)); enum tree_code cand_code = gimple_assign_rhs_code (c->cand_stmt); @@ -2193,6 +2195,11 @@ replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) if (cand_code != NEGATE_EXPR) { rhs1 = gimple_assign_rhs1 (c->cand_stmt); rhs2 = gimple_assign_rhs2 (c->cand_stmt); + /* Mark the 2 original rhs for maybe DCEing. */ + if (TREE_CODE (rhs1) == SSA_NAME) + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (rhs1)); + if (TREE_CODE (rhs2) == SSA_NAME) + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (rhs2)); } if (cand_code != NEGATE_EXPR && ((operand_equal_p (rhs1, basis_name, 0) @@ -2237,7 +2244,7 @@ replace_mult_candidate (slsr_cand_t c, tree basis_name, offset_int bump) folded value ((i - i') * S) is referred to here as the "bump." */ static void -replace_unconditional_candidate (slsr_cand_t c) +replace_unconditional_candidate (slsr_cand_t c, auto_bitmap &sdce_worklist) { slsr_cand_t basis; @@ -2247,7 +2254,8 @@ replace_unconditional_candidate (slsr_cand_t c) basis = lookup_cand (c->basis); offset_int bump = cand_increment (c) * wi::to_offset (c->stride); - replace_mult_candidate (c, gimple_assign_lhs (basis->cand_stmt), bump); + replace_mult_candidate (c, gimple_assign_lhs (basis->cand_stmt), bump, + sdce_worklist); } /* Return the index in the increment vector of the given INCREMENT, @@ -2507,7 +2515,8 @@ create_phi_basis (slsr_cand_t c, gimple *from_phi, tree basis_name, basis. */ static void -replace_conditional_candidate (slsr_cand_t c) +replace_conditional_candidate (slsr_cand_t c, auto_bitmap &sdce_worklist) + { tree basis_name, name; slsr_cand_t basis; @@ -2527,7 +2536,7 @@ replace_conditional_candidate (slsr_cand_t c) /* Replace C with an add of the new basis phi and a constant. */ offset_int bump = c->index * wi::to_offset (c->stride); - replace_mult_candidate (c, name, bump); + replace_mult_candidate (c, name, bump, sdce_worklist); } /* Recursive helper function for phi_add_costs. SPREAD is a measure of @@ -2608,7 +2617,8 @@ phi_add_costs (gimple *phi, slsr_cand_t c, int one_add_cost) so, replace the candidate and introduce the compensation code. */ static void -replace_uncond_cands_and_profitable_phis (slsr_cand_t c) +replace_uncond_cands_and_profitable_phis (slsr_cand_t c, + auto_bitmap &sdce_worklist) { if (phi_dependent_cand_p (c)) { @@ -2643,17 +2653,19 @@ replace_uncond_cands_and_profitable_phis (slsr_cand_t c) } if (cost <= COST_NEUTRAL) - replace_conditional_candidate (c); + replace_conditional_candidate (c, sdce_worklist); } } else - replace_unconditional_candidate (c); + replace_unconditional_candidate (c, sdce_worklist); if (c->sibling) - replace_uncond_cands_and_profitable_phis (lookup_cand (c->sibling)); + replace_uncond_cands_and_profitable_phis (lookup_cand (c->sibling), + sdce_worklist); if (c->dependent) - replace_uncond_cands_and_profitable_phis (lookup_cand (c->dependent)); + replace_uncond_cands_and_profitable_phis (lookup_cand (c->dependent), + sdce_worklist); } /* Count the number of candidates in the tree rooted at C that have @@ -3675,7 +3687,8 @@ replace_rhs_if_not_dup (enum tree_code new_code, tree new_rhs1, tree new_rhs2, is the rhs1 to use in creating the add/subtract. */ static void -replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) +replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name, + auto_bitmap &sdce_worklist) { gimple *stmt_to_print = NULL; tree orig_rhs1, orig_rhs2; @@ -3693,6 +3706,12 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) if (!orig_rhs2) return; + /* Mark the 2 original rhs for maybe DCEing. */ + if (TREE_CODE (orig_rhs1) == SSA_NAME) + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (orig_rhs1)); + if (TREE_CODE (orig_rhs2) == SSA_NAME) + bitmap_set_bit (sdce_worklist, SSA_NAME_VERSION (orig_rhs2)); + if (dump_file && (dump_flags & TDF_DETAILS)) { fputs ("Replacing: ", dump_file); @@ -3835,7 +3854,7 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) an increment if such has been shown to be profitable. */ static void -replace_profitable_candidates (slsr_cand_t c) +replace_profitable_candidates (slsr_cand_t c, auto_bitmap &sdce_worklist) { if (!cand_already_replaced (c)) { @@ -3872,23 +3891,23 @@ replace_profitable_candidates (slsr_cand_t c) /* Replace C with an add of the new basis phi and the increment. */ - replace_one_candidate (c, i, name); + replace_one_candidate (c, i, name, sdce_worklist); } } else { slsr_cand_t basis = lookup_cand (c->basis); tree basis_name = gimple_assign_lhs (basis->cand_stmt); - replace_one_candidate (c, i, basis_name); + replace_one_candidate (c, i, basis_name, sdce_worklist); } } } if (c->sibling) - replace_profitable_candidates (lookup_cand (c->sibling)); + replace_profitable_candidates (lookup_cand (c->sibling), sdce_worklist); if (c->dependent) - replace_profitable_candidates (lookup_cand (c->dependent)); + replace_profitable_candidates (lookup_cand (c->dependent), sdce_worklist); } /* Analyze costs of related candidates in the candidate vector, @@ -3899,6 +3918,7 @@ analyze_candidates_and_replace (void) { unsigned i; slsr_cand_t c; + auto_bitmap simple_dce_worklist; /* Each candidate that has a null basis and a non-null dependent is the root of a tree of related statements. @@ -3932,7 +3952,8 @@ analyze_candidates_and_replace (void) compensation code it requires is offset by the strength reduction savings. */ else if (TREE_CODE (c->stride) == INTEGER_CST) - replace_uncond_cands_and_profitable_phis (first_dep); + replace_uncond_cands_and_profitable_phis (first_dep, + simple_dce_worklist); /* When the stride is an SSA name, it may still be profitable to replace some or all of the dependent candidates, depending @@ -3969,7 +3990,7 @@ analyze_candidates_and_replace (void) dump_incr_vec (); /* Perform the replacements. */ - replace_profitable_candidates (first_dep); + replace_profitable_candidates (first_dep, simple_dce_worklist); free (incr_vec); } } @@ -3977,6 +3998,8 @@ analyze_candidates_and_replace (void) /* For conditional candidates, we may have uncommitted insertions on edges to clean up. */ gsi_commit_edge_inserts (); + + simple_dce_from_worklist (simple_dce_worklist); } namespace {
While working on a phiopt patch, it was noticed that SLSR would leave around some unused ssa names. Let's add simple_dce_from_worklist usage to SLSR to remove the dead statements. This should give a small improvemnent for passes afterwards. Boostrapped and tested on x86_64. gcc/ChangeLog: PR tree-optimization/116554 * gimple-ssa-strength-reduction.cc: Include tree-ssa-dce.h. (replace_mult_candidate): Add sdce_worklist argument, mark the rhs1/rhs2 for maybe dceing. (replace_unconditional_candidate): Add sdce_worklist argument, Update call to replace_mult_candidate. (replace_conditional_candidate): Add sdce_worklist argument, update call to replace_mult_candidate. (replace_uncond_cands_and_profitable_phis): Add sdce_worklist argument, update call to replace_conditional_candidate, replace_unconditional_candidate, and replace_uncond_cands_and_profitable_phis. (replace_one_candidate): Add sdce_worklist argument, mark the orig_rhs1/orig_rhs2 for maybe dceing. (replace_profitable_candidates): Add sdce_worklist argument, update call to replace_one_candidate and replace_profitable_candidates. (analyze_candidates_and_replace): Call simple_dce_from_worklist and update calls to replace_profitable_candidates, and replace_uncond_cands_and_profitable_phis. Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com> --- gcc/gimple-ssa-strength-reduction.cc | 59 +++++++++++++++++++--------- 1 file changed, 41 insertions(+), 18 deletions(-)