diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 988e8c795d4..5f5bd2a7445 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2017-05-12 Richard Biener + + * tree-ssa-sccvn.h (has_VN_INFO): Declare. + * tree-ssa-pre.c (eliminate_dom_walker::before_dom_children): + Fold all stmts not inplace. + 2017-05-12 Richard Biener PR tree-optimization/80713 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index c32d766d195..ff4327a3734 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2017-05-12 Richard Biener + + * g++.dg/tree-ssa/ssa-dse-2.C: Adjust. + 2017-05-12 Paolo Carlini PR c++/67687 diff --git a/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-2.C b/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-2.C index bee86514f01..913df222374 100644 --- a/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-2.C +++ b/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-2.C @@ -54,6 +54,4 @@ fill_vec_av_set (av_set_t av) } /* { dg-final { scan-tree-dump-not "Trimming statement .head = -" "dse2" } } */ -/* { dg-final { scan-tree-dump "Deleted dead call: " "dse2" } } */ - - +/* { dg-final { scan-tree-dump-not "mem\[^\r\n\]*, 0\\);" "dse2" } } */ diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index c7062b73798..e97fdb42b48 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -4645,30 +4645,51 @@ eliminate_dom_walker::before_dom_children (basic_block b) && TREE_CODE (gimple_assign_rhs1 (stmt)) == ADDR_EXPR) recompute_tree_invariant_for_addr_expr (gimple_assign_rhs1 (stmt)); gimple *old_stmt = stmt; - if (is_gimple_call (stmt)) + gimple_stmt_iterator prev = gsi; + gsi_prev (&prev); + if (fold_stmt (&gsi)) { - /* ??? Only fold calls inplace for now, this may create new - SSA names which in turn will confuse free_scc_vn SSA name - release code. */ - fold_stmt_inplace (&gsi); - /* When changing a call into a noreturn call, cfg cleanup - is needed to fix up the noreturn call. */ - if (!was_noreturn && gimple_call_noreturn_p (stmt)) - el_to_fixup.safe_push (stmt); - } - else - { - fold_stmt (&gsi); - stmt = gsi_stmt (gsi); - if ((gimple_code (stmt) == GIMPLE_COND - && (gimple_cond_true_p (as_a (stmt)) - || gimple_cond_false_p (as_a (stmt)))) - || (gimple_code (stmt) == GIMPLE_SWITCH - && TREE_CODE (gimple_switch_index ( - as_a (stmt))) - == INTEGER_CST)) - el_todo |= TODO_cleanup_cfg; + /* fold_stmt may have created new stmts inbetween + the previous stmt and the folded stmt. Mark + all defs created there as varying to not confuse + the SCCVN machinery as we're using that even during + elimination. */ + if (gsi_end_p (prev)) + prev = gsi_start_bb (b); + else + gsi_next (&prev); + if (gsi_stmt (prev) != gsi_stmt (gsi)) + do + { + tree def; + ssa_op_iter dit; + FOR_EACH_SSA_TREE_OPERAND (def, gsi_stmt (prev), + dit, SSA_OP_ALL_DEFS) + /* As existing DEFs may move between stmts + we have to guard VN_INFO_GET. */ + if (! has_VN_INFO (def)) + VN_INFO_GET (def)->valnum = def; + if (gsi_stmt (prev) == gsi_stmt (gsi)) + break; + gsi_next (&prev); + } + while (1); } + stmt = gsi_stmt (gsi); + /* When changing a call into a noreturn call, cfg cleanup + is needed to fix up the noreturn call. */ + if (!was_noreturn + && is_gimple_call (stmt) && gimple_call_noreturn_p (stmt)) + el_to_fixup.safe_push (stmt); + /* When changing a condition or switch into one we know what + edge will be executed, schedule a cfg cleanup. */ + if ((gimple_code (stmt) == GIMPLE_COND + && (gimple_cond_true_p (as_a (stmt)) + || gimple_cond_false_p (as_a (stmt)))) + || (gimple_code (stmt) == GIMPLE_SWITCH + && TREE_CODE (gimple_switch_index + (as_a (stmt))) == INTEGER_CST)) + el_todo |= TODO_cleanup_cfg; /* If we removed EH side-effects from the statement, clean its EH information. */ if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt)) diff --git a/gcc/tree-ssa-sccvn.h b/gcc/tree-ssa-sccvn.h index 53a21afb300..77d0183fcda 100644 --- a/gcc/tree-ssa-sccvn.h +++ b/gcc/tree-ssa-sccvn.h @@ -209,6 +209,7 @@ typedef struct vn_ssa_aux enum vn_lookup_kind { VN_NOWALK, VN_WALK, VN_WALKREWRITE }; /* Return the value numbering info for an SSA_NAME. */ +bool has_VN_INFO (tree); extern vn_ssa_aux_t VN_INFO (tree); extern vn_ssa_aux_t VN_INFO_GET (tree); tree vn_get_expr_for (tree);