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re PR tree-optimization/28868 (Not eliminating the PHIs which have the same arguments)
2009-04-06 Richard Guenther <rguenther@suse.de> PR tree-optimization/28868 * tree-ssa-pre.c (inserted_phi_names): New bitmap to keep track of which PHI results we inserted. (insert_into_preds_of_block): Record inserted PHIs. (eliminate): Eliminate redundant PHI nodes. (init_pre): Init inserted_phi_names. * gcc.dg/tree-ssa/ssa-fre-21.c: New testcase. * gcc.dg/tree-ssa/ssa-sccvn-1.c: Adjust. * gcc.dg/tree-ssa/ssa-sccvn-2.c: Likewise. * gcc.dg/tree-ssa/ssa-sccvn-4.c: Likewise. From-SVN: r145607
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Richard Guenther
Richard Biener
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1ae3576fa4
commit
439ef907ae
@ -1,3 +1,12 @@
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2009-04-06 Richard Guenther <rguenther@suse.de>
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PR tree-optimization/28868
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* tree-ssa-pre.c (inserted_phi_names): New bitmap to keep track
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of which PHI results we inserted.
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(insert_into_preds_of_block): Record inserted PHIs.
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(eliminate): Eliminate redundant PHI nodes.
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(init_pre): Init inserted_phi_names.
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2009-04-06 Richard Guenther <rguenther@suse.de>
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PR tree-optimization/39643
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@ -1,3 +1,11 @@
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2009-04-06 Richard Guenther <rguenther@suse.de>
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PR tree-optimization/28868
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* gcc.dg/tree-ssa/ssa-fre-21.c: New testcase.
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* gcc.dg/tree-ssa/ssa-sccvn-1.c: Adjust.
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* gcc.dg/tree-ssa/ssa-sccvn-2.c: Likewise.
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* gcc.dg/tree-ssa/ssa-sccvn-4.c: Likewise.
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2009-04-06 Andrew Stubbs <ams@codesourcery.com>
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* gcc.dg/pragma-isr-trapa2.c: Skip test for FPU-less architectures.
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21
gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-23.c
Normal file
21
gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-23.c
Normal file
@ -0,0 +1,21 @@
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/* { dg-do compile } */
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/* { dg-options "-O -fdump-tree-fre" } */
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int f(int t, int a, int b)
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{
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int c, d;
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if (t)
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{
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c = a;
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d = a;
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}
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else
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{
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c = b;
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d = b;
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}
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return c+d;
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}
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/* { dg-final { scan-tree-dump-times "PHI" 1 "fre" } } */
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/* { dg-final { cleanup-tree-dump "fre" } } */
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@ -17,5 +17,5 @@ void vnum_test8(int *data)
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}
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}
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/* We should eliminate m - n, and set n = n + k into n = m. */
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/* { dg-final { scan-tree-dump-times "Eliminated: 2" 1 "fre"} } */
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/* { dg-final { scan-tree-dump-times "Eliminated: 3" 1 "fre"} } */
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/* { dg-final { cleanup-tree-dump "fre" } } */
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@ -21,5 +21,5 @@ int vnum_test8(int *data)
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}
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/* We should eliminate m - n, and set n = n + k into n = m, and
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set p to 0 */
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/* { dg-final { scan-tree-dump-times "Eliminated: 3" 1 "fre"} } */
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/* { dg-final { scan-tree-dump-times "Eliminated: 4" 1 "fre"} } */
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/* { dg-final { cleanup-tree-dump "fre" } } */
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@ -23,5 +23,5 @@ int vnum_test8(int *data)
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}
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/* We should eliminate m - n, n + k, set data[5] = 0, eliminate the
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address arithmetic for data[5], and set p = 0.
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/* { dg-final { scan-tree-dump-times "Eliminated: 5" 1 "fre"} } */
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/* { dg-final { scan-tree-dump-times "Eliminated: 6" 1 "fre"} } */
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/* { dg-final { cleanup-tree-dump "fre" } } */
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@ -2597,6 +2597,7 @@ can_PRE_operation (tree op)
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for performing quick dead code elimination of insertions we made
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that didn't turn out to be necessary. */
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static VEC(gimple,heap) *inserted_exprs;
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static bitmap inserted_phi_names;
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/* Pool allocated fake store expressions are placed onto this
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worklist, which, after performing dead code elimination, is walked
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@ -3242,6 +3243,8 @@ insert_into_preds_of_block (basic_block block, unsigned int exprnum,
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VN_INFO_GET (gimple_phi_result (phi))->valnum = gimple_phi_result (phi);
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VN_INFO (gimple_phi_result (phi))->value_id = val;
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VEC_safe_push (gimple, heap, inserted_exprs, phi);
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bitmap_set_bit (inserted_phi_names,
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SSA_NAME_VERSION (gimple_phi_result (phi)));
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FOR_EACH_EDGE (pred, ei, block->preds)
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{
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pre_expr ae = avail[pred->src->index];
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@ -4129,16 +4132,95 @@ eliminate (void)
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}
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}
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}
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for (gsi = gsi_start_phis (b); !gsi_end_p (gsi);)
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{
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gimple stmt, phi = gsi_stmt (gsi);
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tree sprime = NULL_TREE, res = PHI_RESULT (phi);
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pre_expr sprimeexpr, resexpr;
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gimple_stmt_iterator gsi2;
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/* We want to perform redundant PHI elimination. Do so by
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replacing the PHI with a single copy if possible.
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Do not touch inserted, single-argument or virtual PHIs. */
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if (gimple_phi_num_args (phi) == 1
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|| !is_gimple_reg (res)
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|| bitmap_bit_p (inserted_phi_names, SSA_NAME_VERSION (res)))
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{
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gsi_next (&gsi);
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continue;
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}
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resexpr = get_or_alloc_expr_for_name (res);
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sprimeexpr = bitmap_find_leader (AVAIL_OUT (b),
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get_expr_value_id (resexpr), NULL);
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if (sprimeexpr)
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{
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if (sprimeexpr->kind == CONSTANT)
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sprime = PRE_EXPR_CONSTANT (sprimeexpr);
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else if (sprimeexpr->kind == NAME)
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sprime = PRE_EXPR_NAME (sprimeexpr);
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else
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gcc_unreachable ();
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}
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if (!sprimeexpr
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|| sprime == res)
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{
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gsi_next (&gsi);
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continue;
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}
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if (dump_file && (dump_flags & TDF_DETAILS))
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{
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fprintf (dump_file, "Replaced redundant PHI node defining ");
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print_generic_expr (dump_file, res, 0);
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fprintf (dump_file, " with ");
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print_generic_expr (dump_file, sprime, 0);
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fprintf (dump_file, "\n");
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}
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remove_phi_node (&gsi, false);
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stmt = gimple_build_assign (res, sprime);
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SSA_NAME_DEF_STMT (res) = stmt;
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if (TREE_CODE (sprime) == SSA_NAME)
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gimple_set_plf (SSA_NAME_DEF_STMT (sprime),
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NECESSARY, true);
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gsi2 = gsi_after_labels (b);
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gsi_insert_before (&gsi2, stmt, GSI_NEW_STMT);
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/* Queue the copy for eventual removal. */
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VEC_safe_push (gimple, heap, to_remove, stmt);
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pre_stats.eliminations++;
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}
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}
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/* We cannot remove stmts during BB walk, especially not release SSA
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names there as this confuses the VN machinery. */
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names there as this confuses the VN machinery. The stmts ending
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up in to_remove are either stores or simple copies. */
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for (i = 0; VEC_iterate (gimple, to_remove, i, stmt); ++i)
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{
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gsi = gsi_for_stmt (stmt);
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unlink_stmt_vdef (stmt);
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gsi_remove (&gsi, true);
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release_defs (stmt);
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tree lhs = gimple_assign_lhs (stmt);
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use_operand_p use_p;
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gimple use_stmt;
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/* If there is a single use only, propagate the equivalency
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instead of keeping the copy. */
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if (TREE_CODE (lhs) == SSA_NAME
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&& single_imm_use (lhs, &use_p, &use_stmt))
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{
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SET_USE (use_p, gimple_assign_rhs1 (stmt));
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update_stmt (stmt);
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}
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/* If this is a store or a now unused copy, remove it. */
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if (TREE_CODE (lhs) != SSA_NAME
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|| has_zero_uses (lhs))
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{
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gsi = gsi_for_stmt (stmt);
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unlink_stmt_vdef (stmt);
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gsi_remove (&gsi, true);
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release_defs (stmt);
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}
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}
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VEC_free (gimple, heap, to_remove);
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@ -4296,6 +4378,7 @@ init_pre (bool do_fre)
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calculate_dominance_info (CDI_DOMINATORS);
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bitmap_obstack_initialize (&grand_bitmap_obstack);
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inserted_phi_names = BITMAP_ALLOC (&grand_bitmap_obstack);
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phi_translate_table = htab_create (5110, expr_pred_trans_hash,
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expr_pred_trans_eq, free);
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expression_to_id = htab_create (num_ssa_names * 3,
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