diff options
| -rw-r--r-- | ChangeLog | 23 | ||||
| -rw-r--r-- | elaborate.cxx | 9 | ||||
| -rw-r--r-- | parse.cxx | 9 | ||||
| -rw-r--r-- | stap.1.in | 9 | ||||
| -rw-r--r-- | staptree.cxx | 10 | ||||
| -rw-r--r-- | staptree.h | 1 | ||||
| -rw-r--r-- | translate.cxx | 107 |
7 files changed, 157 insertions, 11 deletions
@@ -1,3 +1,26 @@ +2006-11-06 David Smith <dsmith@redhat.com> + + Added "limit EXP" support to foreach statements. + * translate.cxx (c_tmpcounter::visit_foreach_loop): Handles + "limit" member variable. + (c_unparser::visit_foreach_loop): Ditto. + * staptree.cxx (foreach_loop::print): Prints "limit EXP" + addition. + (traversing_visitor::visit_foreach_loop): Handles "limit" member + variable. + (deep_copy_visitor::visit_foreach_loop): Ditto. + * staptree.h (struct foreach_loop): Added "limit" member + variable. + * stap.1.in: Added documentation for the "limit EXP" addition to + foreach statement. + * parse.cxx (lexer::scan): Added "limit" keyword for foreach + statements. + (parser::parse_foreach_loop): Parses "limit" keyword for foreach + statements. + * elaborate.cxx (symresolution_info::visit_foreach_loop): Handles + "limit" member variable. + (typeresolution_info::visit_foreach_loop): Ditto. + 2006-11-03 Frank Ch. Eigler <fche@elastic.org> * tapsets.cxx (emit_address): Emit calls to _stp_module_relocate diff --git a/elaborate.cxx b/elaborate.cxx index f6c9bf9a..c532d0b0 100644 --- a/elaborate.cxx +++ b/elaborate.cxx @@ -1040,6 +1040,9 @@ symresolution_info::visit_foreach_loop (foreach_loop* e) hist->visit (this); } + if (e->limit) + e->limit->visit (this); + e->block->visit (this); } @@ -2375,6 +2378,12 @@ typeresolution_info::visit_foreach_loop (foreach_loop* e) } } + if (e->limit) + { + t = pe_long; + e->limit->visit (this); + } + t = pe_unknown; e->block->visit (this); } @@ -543,6 +543,7 @@ lexer::scan () || n->content == "for" || n->content == "foreach" || n->content == "in" + || n->content == "limit" || n->content == "return" || n->content == "delete" || n->content == "while" @@ -1518,6 +1519,7 @@ parser::parse_foreach_loop () foreach_loop* s = new foreach_loop; s->tok = t; s->sort_direction = 0; + s->limit = NULL; t = next (); if (! (t->type == tok_operator && t->content == "(")) @@ -1591,6 +1593,13 @@ parser::parse_foreach_loop () next(); } + t = peek (); + if (tok_is(t, tok_keyword, "limit")) + { + next (); // get past the "limit" + s->limit = parse_expression (); + } + t = next (); if (! (t->type == tok_operator && t->content == ")")) throw parse_error ("expected ')'"); @@ -304,15 +304,20 @@ While integer-valued EXP evaluates to non-zero, execute STMT. Execute EXP1 as initialization. While EXP2 is non-zero, execute STMT, then the iteration expression EXP3. .TP -.BR foreach " (VAR " in " ARRAY) STMT" +.BR foreach " (VAR " in " ARRAY [ "limit " EXP ]) STMT" Loop over each element of the named global array, assigning current key to VAR. The array may not be modified within the statement. By adding a single .BR + " or " \- operator after the VAR or the ARRAY identifier, the iteration will proceed in a sorted order, by ascending or descending index or value. + +Using the optional +.BR limit +keyword limits the number of loop iterations to EXP times. EXP is +evaluted once at the beginning of the loop. .TP -.BR foreach " ([VAR1, VAR2, ...] " in " ARRAY) STMT" +.BR foreach " ([VAR1, VAR2, ...] " in " ARRAY [ "limit " EXP ]) STMT" Same as above, used when the array is indexed with a tuple of keys. A sorting suffix may be used on at most one VAR or ARRAY identifier. .TP diff --git a/staptree.cxx b/staptree.cxx index 36712c12..fdfc516c 100644 --- a/staptree.cxx +++ b/staptree.cxx @@ -752,6 +752,11 @@ void foreach_loop::print (ostream& o) const base->print_indexable (o); if (sort_direction != 0 && sort_column == 0) o << (sort_direction > 0 ? "+" : "-"); + if (limit) + { + o << " limit "; + limit->print (o); + } o << ") "; block->print (o); } @@ -1320,6 +1325,10 @@ traversing_visitor::visit_foreach_loop (foreach_loop* s) for (unsigned i=0; i<s->indexes.size(); i++) s->indexes[i]->visit (this); + + if (s->limit) + s->limit->visit (this); + s->block->visit (this); } @@ -1965,6 +1974,7 @@ deep_copy_visitor::visit_foreach_loop (foreach_loop* s) n->sort_direction = s->sort_direction; n->sort_column = s->sort_column; + require <expression*> (this, &(n->limit), s->limit); require <statement*> (this, &(n->block), s->block); provide <foreach_loop*> (this, n); @@ -464,6 +464,7 @@ struct foreach_loop: public statement indexable *base; int sort_direction; // -1: decreasing, 0: none, 1: increasing unsigned sort_column; // 0: value, 1..N: index + expression* limit; // optional iteration limit statement* block; void print (std::ostream& o) const; diff --git a/translate.cxx b/translate.cxx index 1f2e47f0..14d58ef2 100644 --- a/translate.cxx +++ b/translate.cxx @@ -2196,6 +2196,19 @@ c_tmpcounter::visit_foreach_loop (foreach_loop *s) } } + // Create a temporary for the loop limit counter and the limit + // expression result. + if (s->limit) + { + tmpvar res_limit = parent->gensym (pe_long); + res_limit.declare(*parent); + + s->limit->visit (this); + + tmpvar limitv = parent->gensym (pe_long); + limitv.declare(*parent); + } + s->block->visit (this); } @@ -2223,6 +2236,14 @@ c_unparser::visit_foreach_loop (foreach_loop *s) // initialization + tmpvar *res_limit = NULL; + if (s->limit) + { + // Evaluate the limit expression once. + res_limit = new tmpvar(gensym(pe_long)); + c_assign (res_limit->qname(), s->limit, "foreach limit"); + } + // aggregate array if required if (mv.is_parallel()) { @@ -2231,20 +2252,43 @@ c_unparser::visit_foreach_loop (foreach_loop *s) o->indent(-1); // sort array if desired - if (s->sort_direction) { - o->newline() << "else"; // only sort if aggregation was ok - o->newline(1) << "_stp_map_sort (" << mv.fetch_existing_aggregate() << ", " - << s->sort_column << ", " << - s->sort_direction << ");"; - o->indent(-1); - } - } + if (s->sort_direction) + { + o->newline() << "else"; // only sort if aggregation was ok + if (s->limit) + { + o->newline(1) << "_stp_map_sortn (" + << mv.fetch_existing_aggregate() << ", " + << *res_limit << ", " << s->sort_column << ", " + << - s->sort_direction << ");"; + } + else + { + o->newline(1) << "_stp_map_sort (" + << mv.fetch_existing_aggregate() << ", " + << s->sort_column << ", " + << - s->sort_direction << ");"; + } + o->indent(-1); + } + } else { // sort array if desired if (s->sort_direction) { - o->newline() << "_stp_map_sort (" << mv.qname() << ", " - << s->sort_column << ", " << - s->sort_direction << ");"; + if (s->limit) + { + o->newline() << "_stp_map_sortn (" << mv.qname() << ", " + << *res_limit << ", " << s->sort_column << ", " + << - s->sort_direction << ");"; + } + else + { + o->newline() << "_stp_map_sort (" << mv.qname() << ", " + << s->sort_column << ", " + << - s->sort_direction << ");"; + } } } @@ -2254,6 +2298,14 @@ c_unparser::visit_foreach_loop (foreach_loop *s) aggregations_active.insert(mv.qname()); o->newline() << iv << " = " << iv.start (mv) << ";"; + tmpvar *limitv = NULL; + if (s->limit) + { + // Create the loop limit variable here and initialize it. + limitv = new tmpvar(gensym (pe_long)); + o->newline() << *limitv << " = 0LL;"; + } + // condition o->newline(-1) << toplabel << ":"; @@ -2270,6 +2322,18 @@ c_unparser::visit_foreach_loop (foreach_loop *s) loop_continue_labels.push_back (contlabel); o->newline() << "{"; o->indent (1); + + if (s->limit) + { + // If we've been through LIMIT loop iterations, quit. + o->newline() << "if (" << *limitv << "++ >= " << *res_limit + << ") goto " << breaklabel << ";"; + + // We're done with limitv and res_limit. + delete limitv; + delete res_limit; + } + for (unsigned i = 0; i < s->indexes.size(); ++i) { // copy the iter values into the specified locals @@ -2307,11 +2371,36 @@ c_unparser::visit_foreach_loop (foreach_loop *s) var v = getvar(sym->referent, sym->tok); v.assert_hist_compatible(*hist); + tmpvar *res_limit = NULL; + tmpvar *limitv = NULL; + if (s->limit) + { + // Evaluate the limit expression once. + res_limit = new tmpvar(gensym(pe_long)); + c_assign (res_limit->qname(), s->limit, "foreach limit"); + + // Create the loop limit variable here and initialize it. + limitv = new tmpvar(gensym (pe_long)); + o->newline() << *limitv << " = 0LL;"; + } + // XXX: break / continue don't work here yet o->newline() << "for (" << bucketvar << " = 0; " << bucketvar << " < " << v.buckets() << "; " << bucketvar << "++) { "; o->newline(1); + + if (s->limit) + { + // If we've been through LIMIT loop iterations, quit. + o->newline() << "if (" << *limitv << "++ >= " << *res_limit + << ") break;"; + + // We're done with limitv and res_limit. + delete limitv; + delete res_limit; + } + s->block->visit (this); o->newline(-1) << "}"; } |