From 7d25ac209de8262e39e5551585da5094a4c5c317 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 27 Jul 2017 10:49:16 +0200 Subject: re PR tree-optimization/81555 (Wrong code at -O1) PR tree-optimization/81555 PR tree-optimization/81556 * tree-ssa-reassoc.c (rewrite_expr_tree): Add NEXT_CHANGED argument, if true, force CHANGED for the recursive invocation. (reassociate_bb): Remember original length of ops array, pass len != orig_len as NEXT_CHANGED in rewrite_expr_tree call. * gcc.c-torture/execute/pr81555.c: New test. * gcc.c-torture/execute/pr81556.c: New test. From-SVN: r250609 --- gcc/tree-ssa-reassoc.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'gcc/tree-ssa-reassoc.c') diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c index 2f49ba1..7c3007f 100644 --- a/gcc/tree-ssa-reassoc.c +++ b/gcc/tree-ssa-reassoc.c @@ -4205,11 +4205,15 @@ insert_stmt_before_use (gimple *stmt, gimple *stmt_to_insert) /* Recursively rewrite our linearized statements so that the operators match those in OPS[OPINDEX], putting the computation in rank - order. Return new lhs. */ + order. Return new lhs. + CHANGED is true if we shouldn't reuse the lhs SSA_NAME both in + the current stmt and during recursive invocations. + NEXT_CHANGED is true if we shouldn't reuse the lhs SSA_NAME in + recursive invocations. */ static tree rewrite_expr_tree (gimple *stmt, unsigned int opindex, - vec ops, bool changed) + vec ops, bool changed, bool next_changed) { tree rhs1 = gimple_assign_rhs1 (stmt); tree rhs2 = gimple_assign_rhs2 (stmt); @@ -4300,7 +4304,8 @@ rewrite_expr_tree (gimple *stmt, unsigned int opindex, be the non-leaf side. */ tree new_rhs1 = rewrite_expr_tree (SSA_NAME_DEF_STMT (rhs1), opindex + 1, ops, - changed || oe->op != rhs2); + changed || oe->op != rhs2 || next_changed, + false); if (oe->op != rhs2 || new_rhs1 != rhs1) { @@ -5654,6 +5659,7 @@ reassociate_bb (basic_block bb) gimple_set_visited (stmt, true); linearize_expr_tree (&ops, stmt, true, true); ops.qsort (sort_by_operand_rank); + int orig_len = ops.length (); optimize_ops_list (rhs_code, &ops); if (undistribute_ops_list (rhs_code, &ops, loop_containing_stmt (stmt))) @@ -5744,7 +5750,8 @@ reassociate_bb (basic_block bb) new_lhs = rewrite_expr_tree (stmt, 0, ops, powi_result != NULL - || negate_result); + || negate_result, + len != orig_len); } /* If we combined some repeated factors into a -- cgit v1.1