compile.c: add a RUBY_EVENT_COVERAGE_LINE event for line coverage

2.5's line coverage measurement was about two times slower than 2.4
because of two reasons; (1) vm_trace uses rb_iseq_event_flags (which
takes O(n) currently where n is the length of iseq) to get an event
type, and (2) RUBY_EVENT_LINE uses setjmp to call an event hook.

This change adds a special event for line coverage,
RUBY_EVENT_COVERAGE_LINE, and adds `tracecoverage` instructions where
the event occurs in iseq.
`tracecoverage` instruction calls an event hook without vm_trace.
And, RUBY_EVENT_COVERAGE_LINE is an internal event which does not
use setjmp.

This change also cancells lineno change due to the deletion of trace
instructions [Feature #14104].  So fixes [Bug #14191].

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61350 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

compile.c

@@ -250,6 +250,16 @@ struct iseq_compile_data_ensure_node_stack {
 
 #define ADD_TRACE(seq, event) \
   ADD_ELEM((seq), (LINK_ELEMENT *)new_trace_body(iseq, (event)))
+#define ADD_TRACE_LINE_COVERAGE(seq, line) \
+  do { \
+      if (ISEQ_COVERAGE(iseq) && \
+	  ISEQ_LINE_COVERAGE(iseq) && \
+	  (line) > 0) { \
+	  RARRAY_ASET(ISEQ_LINE_COVERAGE(iseq), (line) - 1, INT2FIX(0)); \
+	  ADD_INSN2((seq), (line), tracecoverage, INT2FIX(RUBY_EVENT_COVERAGE_LINE), INT2FIX(line)); \
+      } \
+  } while (0)
+
 
 #define DECL_BRANCH_BASE(branches, first_line, first_column, last_line, last_column, type) \
   do { \
@@ -280,7 +290,7 @@ struct iseq_compile_data_ensure_node_stack {
 	  rb_ary_push(branches, INT2FIX(last_line)); \
 	  rb_ary_push(branches, INT2FIX(last_column)); \
 	  rb_ary_push(branches, INT2FIX(counter_idx)); \
-	  ADD_INSN2((seq), (first_line), tracebranch, INT2FIX(RUBY_EVENT_COVERAGE_BRANCH), INT2FIX(counter_idx)); \
+	  ADD_INSN2((seq), (first_line), tracecoverage, INT2FIX(RUBY_EVENT_COVERAGE_BRANCH), INT2FIX(counter_idx)); \
       } \
   } while (0)
 
@@ -5421,6 +5431,7 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node, in
     else {
 	if (node->flags & NODE_FL_NEWLINE) {
 	    ISEQ_COMPILE_DATA(iseq)->last_line = line;
+	    ADD_TRACE_LINE_COVERAGE(ret, line);
 	    ADD_TRACE(ret, RUBY_EVENT_LINE);
 	}
     }

include/ruby/ruby.h

@@ -2111,7 +2111,7 @@ int ruby_native_thread_p(void);
 #define RUBY_INTERNAL_EVENT_GC_ENTER       0x2000000
 #define RUBY_INTERNAL_EVENT_GC_EXIT        0x4000000
 #define RUBY_INTERNAL_EVENT_OBJSPACE_MASK  0x7f00000
-#define RUBY_INTERNAL_EVENT_MASK          0xfffe0000
+#define RUBY_INTERNAL_EVENT_MASK          0xffff0000
 
 typedef uint32_t rb_event_flag_t;
 typedef void (*rb_event_hook_func_t)(rb_event_flag_t evflag, VALUE data, VALUE self, ID mid, VALUE klass);

insns.def

@@ -778,11 +778,11 @@ checkkeyword
 
 /**
   @c setting
-  @e trace a branch
-  @j 分岐を trace する
+  @e fire a coverage event (currently, this is used for line coverage and branch coverage)
+  @j カバレッジイベントを trace する
  */
 DEFINE_INSN
-tracebranch
+tracecoverage
 (rb_num_t nf, VALUE data)
 ()
 ()

iseq.c

@@ -350,21 +350,9 @@ finish_iseq_build(rb_iseq_t *iseq)
 {
     struct iseq_compile_data *data = ISEQ_COMPILE_DATA(iseq);
     VALUE err = data->err_info;
-    unsigned int i;
     ISEQ_COMPILE_DATA_CLEAR(iseq);
     compile_data_free(data);
 
-    if (ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq)) {
-	for (i = 0; i < iseq->body->insns_info_size; i++) {
-	    if (iseq->body->insns_info[i].events & RUBY_EVENT_LINE) {
-		int line_no = iseq->body->insns_info[i].line_no - 1;
-		if (0 <= line_no && line_no < RARRAY_LEN(ISEQ_LINE_COVERAGE(iseq))) {
-		    RARRAY_ASET(ISEQ_LINE_COVERAGE(iseq), line_no, INT2FIX(0));
-		}
-	    }
-	}
-    }
-
     if (RTEST(err)) {
 	VALUE path = pathobj_path(iseq->body->location.pathobj);
 	if (err == Qtrue) err = rb_exc_new_cstr(rb_eSyntaxError, "compile error");

thread.c

@@ -5035,7 +5035,7 @@ update_line_coverage(VALUE data, const rb_trace_arg_t *trace_arg)
     if (RB_TYPE_P(coverage, T_ARRAY) && !RBASIC_CLASS(coverage)) {
 	VALUE lines = RARRAY_AREF(coverage, COVERAGE_INDEX_LINES);
 	if (lines) {
-	    long line = rb_sourceline() - 1;
+	    long line = FIX2INT(trace_arg->data) - 1;
 	    long count;
 	    VALUE num;
 	    if (line >= RARRAY_LEN(lines)) { /* no longer tracked */
@@ -5157,7 +5157,7 @@ rb_set_coverages(VALUE coverages, int mode, VALUE me2counter)
 {
     GET_VM()->coverages = coverages;
     GET_VM()->coverage_mode = mode;
-    rb_add_event_hook2((rb_event_hook_func_t) update_line_coverage, RUBY_EVENT_LINE, Qnil, RUBY_EVENT_HOOK_FLAG_SAFE | RUBY_EVENT_HOOK_FLAG_RAW_ARG);
+    rb_add_event_hook2((rb_event_hook_func_t) update_line_coverage, RUBY_EVENT_COVERAGE_LINE, Qnil, RUBY_EVENT_HOOK_FLAG_SAFE | RUBY_EVENT_HOOK_FLAG_RAW_ARG);
     if (mode & COVERAGE_TARGET_BRANCHES) {
 	rb_add_event_hook2((rb_event_hook_func_t) update_branch_coverage, RUBY_EVENT_COVERAGE_BRANCH, Qnil, RUBY_EVENT_HOOK_FLAG_SAFE | RUBY_EVENT_HOOK_FLAG_RAW_ARG);
     }

vm_core.h

@@ -1755,7 +1755,8 @@ RUBY_SYMBOL_EXPORT_BEGIN
 int rb_thread_check_trap_pending(void);
 
 /* #define RUBY_EVENT_RESERVED_FOR_INTERNAL_USE 0x030000 */ /* from vm_core.h */
-#define RUBY_EVENT_COVERAGE_BRANCH              0x010000
+#define RUBY_EVENT_COVERAGE_LINE                0x010000
+#define RUBY_EVENT_COVERAGE_BRANCH              0x020000
 
 extern VALUE rb_get_coverages(void);
 extern void rb_set_coverages(VALUE, int, VALUE);