diff options
Diffstat (limited to 'gcc/tree-inline.c')
| -rw-r--r-- | gcc/tree-inline.c | 43 |
1 files changed, 36 insertions, 7 deletions
diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c index ebb413a..65ffd91 100644 --- a/gcc/tree-inline.c +++ b/gcc/tree-inline.c @@ -186,15 +186,42 @@ remap_ssa_name (tree name, copy_body_data *id) { new = make_ssa_name (new, NULL); insert_decl_map (id, name, new); - if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (name))) - { - SSA_NAME_DEF_STMT (new) = build_empty_stmt (); - if (gimple_default_def (id->src_cfun, SSA_NAME_VAR (name)) == name) - set_default_def (SSA_NAME_VAR (new), new); - } SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new) = SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name); TREE_TYPE (new) = TREE_TYPE (SSA_NAME_VAR (new)); + if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (name))) + { + /* By inlining function having uninitialized variable, we might + extend the lifetime (variable might get reused). This cause + ICE in the case we end up extending lifetime of SSA name across + abnormal edge, but also increase register presure. + + We simply initialize all uninitialized vars by 0 except for case + we are inlining to very first BB. We can avoid this for all + BBs that are not withing strongly connected regions of the CFG, + but this is bit expensive to test. + */ + if (id->entry_bb && is_gimple_reg (SSA_NAME_VAR (name)) + && TREE_CODE (SSA_NAME_VAR (name)) != PARM_DECL + && (id->entry_bb != EDGE_SUCC (ENTRY_BLOCK_PTR, 0) + || EDGE_COUNT (id->entry_bb->preds) != 1)) + { + block_stmt_iterator bsi = bsi_last (id->entry_bb); + tree init_stmt + = build_gimple_modify_stmt (new, + fold_convert (TREE_TYPE (new), + integer_zero_node)); + bsi_insert_after (&bsi, init_stmt, BSI_NEW_STMT); + SSA_NAME_DEF_STMT (new) = init_stmt; + SSA_NAME_IS_DEFAULT_DEF (new) = 0; + } + else + { + SSA_NAME_DEF_STMT (new) = build_empty_stmt (); + if (gimple_default_def (id->src_cfun, SSA_NAME_VAR (name)) == name) + set_default_def (SSA_NAME_VAR (new), new); + } + } } else insert_decl_map (id, name, new); @@ -259,7 +286,8 @@ remap_decl (tree decl, copy_body_data *id) tree map = remap_ssa_name (def, id); /* Watch out RESULT_DECLs whose SSA names map directly to them. */ - if (TREE_CODE (map) == SSA_NAME) + if (TREE_CODE (map) == SSA_NAME + && IS_EMPTY_STMT (SSA_NAME_DEF_STMT (map))) set_default_def (t, map); } add_referenced_var (t); @@ -2698,6 +2726,7 @@ expand_call_inline (basic_block bb, tree stmt, tree *tp, void *data) gcc_assert (!id->src_cfun->after_inlining); + id->entry_bb = bb; initialize_inlined_parameters (id, t, fn, bb); if (DECL_INITIAL (fn)) |