From cc99c1e1f3172ea39b325f7a31e9112e5e8c3b88 Mon Sep 17 00:00:00 2001 From: rguenth Date: Mon, 18 Mar 2013 08:53:42 +0000 Subject: 2013-03-18 Richard Biener PR tree-optimization/3713 * tree-ssa-sccvn.c (visit_copy): Simplify. Always propagate has_constants and expr. (stmt_has_constants): Properly valueize SSA names when deciding whether the stmt has constants. * g++.dg/ipa/devirt-12.C: New testcase. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@196771 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/tree-ssa-sccvn.c | 46 +++++++++++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 19 deletions(-) (limited to 'gcc/tree-ssa-sccvn.c') diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index c63aa2d0eca..8360cc73000 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -2652,18 +2652,13 @@ static tree valueize_expr (tree expr); static bool visit_copy (tree lhs, tree rhs) { - /* Follow chains of copies to their destination. */ - while (TREE_CODE (rhs) == SSA_NAME - && SSA_VAL (rhs) != rhs) - rhs = SSA_VAL (rhs); - /* The copy may have a more interesting constant filled expression (we don't, since we know our RHS is just an SSA name). */ - if (TREE_CODE (rhs) == SSA_NAME) - { - VN_INFO (lhs)->has_constants = VN_INFO (rhs)->has_constants; - VN_INFO (lhs)->expr = VN_INFO (rhs)->expr; - } + VN_INFO (lhs)->has_constants = VN_INFO (rhs)->has_constants; + VN_INFO (lhs)->expr = VN_INFO (rhs)->expr; + + /* And finally valueize. */ + rhs = SSA_VAL (rhs); return set_ssa_val_to (lhs, rhs); } @@ -3062,25 +3057,38 @@ expr_has_constants (tree expr) static bool stmt_has_constants (gimple stmt) { + tree tem; + if (gimple_code (stmt) != GIMPLE_ASSIGN) return false; switch (get_gimple_rhs_class (gimple_assign_rhs_code (stmt))) { - case GIMPLE_UNARY_RHS: - return is_gimple_min_invariant (gimple_assign_rhs1 (stmt)); + case GIMPLE_TERNARY_RHS: + tem = gimple_assign_rhs3 (stmt); + if (TREE_CODE (tem) == SSA_NAME) + tem = SSA_VAL (tem); + if (is_gimple_min_invariant (tem)) + return true; + /* Fallthru. */ case GIMPLE_BINARY_RHS: - return (is_gimple_min_invariant (gimple_assign_rhs1 (stmt)) - || is_gimple_min_invariant (gimple_assign_rhs2 (stmt))); - case GIMPLE_TERNARY_RHS: - return (is_gimple_min_invariant (gimple_assign_rhs1 (stmt)) - || is_gimple_min_invariant (gimple_assign_rhs2 (stmt)) - || is_gimple_min_invariant (gimple_assign_rhs3 (stmt))); + tem = gimple_assign_rhs2 (stmt); + if (TREE_CODE (tem) == SSA_NAME) + tem = SSA_VAL (tem); + if (is_gimple_min_invariant (tem)) + return true; + /* Fallthru. */ + case GIMPLE_SINGLE_RHS: /* Constants inside reference ops are rarely interesting, but it can take a lot of looking to find them. */ - return is_gimple_min_invariant (gimple_assign_rhs1 (stmt)); + case GIMPLE_UNARY_RHS: + tem = gimple_assign_rhs1 (stmt); + if (TREE_CODE (tem) == SSA_NAME) + tem = SSA_VAL (tem); + return is_gimple_min_invariant (tem); + default: gcc_unreachable (); } -- cgit v1.2.1