diff options
Diffstat (limited to 'elaborate.cxx')
| -rw-r--r-- | elaborate.cxx | 185 |
1 files changed, 148 insertions, 37 deletions
diff --git a/elaborate.cxx b/elaborate.cxx index 2d9fa7bc..306baff1 100644 --- a/elaborate.cxx +++ b/elaborate.cxx @@ -492,7 +492,6 @@ alias_expansion_builder // the token location of the alias, n->tok = location->tok; - n->body->tok = location->tok; // and statements representing the concatenation of the alias' // body with the use's. @@ -503,25 +502,9 @@ alias_expansion_builder // resulting variable. if (alias->epilogue_style) - { - for (unsigned i = 0; i < use->body->statements.size(); ++i) - n->body->statements.push_back - (deep_copy_visitor::deep_copy(use->body->statements[i])); - - for (unsigned i = 0; i < alias->body->statements.size(); ++i) - n->body->statements.push_back - (deep_copy_visitor::deep_copy(alias->body->statements[i])); - } + n->body = new block (use->body, alias->body); else - { - for (unsigned i = 0; i < alias->body->statements.size(); ++i) - n->body->statements.push_back - (deep_copy_visitor::deep_copy(alias->body->statements[i])); - - for (unsigned i = 0; i < use->body->statements.size(); ++i) - n->body->statements.push_back - (deep_copy_visitor::deep_copy(use->body->statements[i])); - } + n->body = new block (alias->body, use->body); derive_probes (sess, n, finished_results, location->optional); } @@ -1041,7 +1024,7 @@ semantic_pass_conditions (systemtap_session & sess) notex->tok = e->tok; notex->operand = e; ifs->condition = notex; - p->body->statements.insert (p->body->statements.begin(), ifs); + p->body = new block (ifs, p->body); } } @@ -1197,6 +1180,8 @@ systemtap_session::systemtap_session (): be_derived_probes(0), dwarf_derived_probes(0), uprobe_derived_probes(0), + utrace_derived_probes(0), + task_finder_derived_probes(0), timer_derived_probes(0), profile_derived_probes(0), mark_derived_probes(0), @@ -1214,6 +1199,9 @@ systemtap_session::print_error (const semantic_error& e) string message_str; stringstream message; + // NB: we don't print error messages during listing mode. + if (listing_mode) return; + message << "semantic error: " << e.what (); if (e.tok1 || e.tok2) message << ": "; @@ -1794,6 +1782,7 @@ struct dead_stmtexpr_remover: public traversing_visitor session(s), relaxed_p(r), current_stmt(0) {} void visit_block (block *s); + void visit_null_statement (null_statement *s); void visit_if_statement (if_statement* s); void visit_foreach_loop (foreach_loop *s); void visit_for_loop (for_loop *s); @@ -1804,15 +1793,44 @@ struct dead_stmtexpr_remover: public traversing_visitor void +dead_stmtexpr_remover::visit_null_statement (null_statement *s) +{ + // easy! + if (session.verbose>2) + clog << "Eliding side-effect-free null statement " << *s->tok << endl; + *current_stmt = 0; +} + + +void dead_stmtexpr_remover::visit_block (block *s) { - for (unsigned i=0; i<s->statements.size(); i++) + vector<statement*> new_stmts; + for (unsigned i=0; i<s->statements.size(); i++ ) { statement** last_stmt = current_stmt; current_stmt = & s->statements[i]; s->statements[i]->visit (this); + if (*current_stmt != 0) + new_stmts.push_back (*current_stmt); current_stmt = last_stmt; } + if (new_stmts.size() == 0) + { + if (session.verbose>2) + clog << "Eliding side-effect-free empty block " << *s->tok << endl; + *current_stmt = 0; + } + else if (new_stmts.size() == 1) + { + if (session.verbose>2) + clog << "Eliding side-effect-free singleton block " << *s->tok << endl; + *current_stmt = new_stmts[0]; + } + else + { + s->statements = new_stmts; + } } void @@ -1821,12 +1839,36 @@ dead_stmtexpr_remover::visit_if_statement (if_statement *s) statement** last_stmt = current_stmt; current_stmt = & s->thenblock; s->thenblock->visit (this); + if (s->elseblock) { current_stmt = & s->elseblock; s->elseblock->visit (this); + // null *current_stmt is OK here. } current_stmt = last_stmt; + + if (s->elseblock == 0 && s->thenblock == 0) + { + // We may be able to elide this statement, if the condition + // expression is side-effect-free. + varuse_collecting_visitor vct; + s->condition->visit(& vct); + if (vct.side_effect_free ()) + { + if (session.verbose>2) + clog << "Eliding side-effect-free if statement " << *s->tok << endl; + *current_stmt = 0; // yeah, baby + return; + } + } + + if (s->thenblock == 0) + { + // Can't elide this whole if/else statement; put a null in there. + s->thenblock = new null_statement(); + s->thenblock->tok = s->tok; + } } void @@ -1836,6 +1878,13 @@ dead_stmtexpr_remover::visit_foreach_loop (foreach_loop *s) current_stmt = & s->block; s->block->visit (this); current_stmt = last_stmt; + + if (s->block == 0) + { + if (session.verbose>2) + clog << "Eliding side-effect-free foreach statement " << *s->tok << endl; + *current_stmt = 0; // yeah, baby + } } void @@ -1845,6 +1894,27 @@ dead_stmtexpr_remover::visit_for_loop (for_loop *s) current_stmt = & s->block; s->block->visit (this); current_stmt = last_stmt; + + if (s->block == 0) + { + // We may be able to elide this statement, if the condition + // expression is side-effect-free. + varuse_collecting_visitor vct; + if (s->init) s->init->visit(& vct); + s->cond->visit(& vct); + if (s->incr) s->incr->visit(& vct); + if (vct.side_effect_free ()) + { + if (session.verbose>2) + clog << "Eliding side-effect-free for statement " << *s->tok << endl; + *current_stmt = 0; // yeah, baby + return; + } + + // Can't elide this whole statement; put a null in there. + s->block = new null_statement(); + s->block->tok = s->tok; + } } @@ -1881,14 +1951,10 @@ dead_stmtexpr_remover::visit_expr_statement (expr_statement *s) clog << "Eliding side-effect-free expression " << *s->tok << endl; - null_statement* ns = new null_statement; - ns->tok = s->tok; - * current_stmt = ns; - // XXX: A null_statement carries more weight in the translator's - // output than a nonexistent statement. It might be nice to - // work a little harder and completely eliminate all traces of - // an elided statement. - + // NB: this 0 pointer is invalid to leave around for any length of + // time, but the parent parse tree objects above handle it. + * current_stmt = 0; + relaxed_p = false; } } @@ -1905,23 +1971,48 @@ void semantic_pass_opt4 (systemtap_session& s, bool& relaxed_p) for (unsigned i=0; i<s.probes.size(); i++) { + derived_probe* p = s.probes[i]; + duv.focal_vars.clear (); duv.focal_vars.insert (s.globals.begin(), s.globals.end()); - duv.focal_vars.insert (s.probes[i]->locals.begin(), - s.probes[i]->locals.end()); - s.probes[i]->body->visit (& duv); + duv.focal_vars.insert (p->locals.begin(), + p->locals.end()); + + duv.current_stmt = & p->body; + p->body->visit (& duv); + if (p->body == 0) + { + if (! s.suppress_warnings) + clog << "WARNING: side-effect-free probe '" << p->name << "' " + << *p->tok << endl; + + p->body = new null_statement(); + p->body->tok = p->tok; + } } for (unsigned i=0; i<s.functions.size(); i++) { + functiondecl* fn = s.functions[i]; duv.focal_vars.clear (); - duv.focal_vars.insert (s.functions[i]->locals.begin(), - s.functions[i]->locals.end()); - duv.focal_vars.insert (s.functions[i]->formal_args.begin(), - s.functions[i]->formal_args.end()); + duv.focal_vars.insert (fn->locals.begin(), + fn->locals.end()); + duv.focal_vars.insert (fn->formal_args.begin(), + fn->formal_args.end()); duv.focal_vars.insert (s.globals.begin(), s.globals.end()); - s.functions[i]->body->visit (& duv); + + duv.current_stmt = & fn->body; + fn->body->visit (& duv); + if (fn->body == 0) + { + if (! s.suppress_warnings) + clog << "WARNING: side-effect-free function '" << fn->name << "' " + << *fn->tok << endl; + + fn->body = new null_statement(); + fn->body->tok = fn->tok; + } } } @@ -2504,6 +2595,26 @@ typeresolution_info::visit_target_symbol (target_symbol* e) // later unused-expression-elimination pass didn't get rid of it // either. So we have a target symbol that is believed to be of // genuine use, yet unresolved by the provider. + + if (session.verbose > 2) + { + clog << "Resolution problem with "; + if (current_function) + { + clog << "function " << current_function->name << endl; + current_function->body->print (clog); + clog << endl; + } + else if (current_probe) + { + clog << "probe " << current_probe->name << endl; + current_probe->body->print (clog); + clog << endl; + } + else + clog << "other" << endl; + } + if (e->saved_conversion_error) throw (* (e->saved_conversion_error)); else |