2 // Copyright (C) 2005-2009 Red Hat Inc.
3 // Copyright (C) 2005-2008 Intel Corporation.
5 // This file is part of systemtap, and is free software. You can
6 // redistribute it and/or modify it under the terms of the GNU General
7 // Public License (GPL); either version 2, or (at your option) any
12 #include "elaborate.h"
13 #include "translate.h"
17 #include "dwarf_wrappers.h"
28 #include <elfutils/libdwfl.h>
29 #ifdef HAVE_ELFUTILS_VERSION_H
30 #include <elfutils/version.h>
42 struct c_unparser
: public unparser
, public visitor
44 systemtap_session
* session
;
47 derived_probe
* current_probe
;
48 functiondecl
* current_function
;
49 unsigned tmpvar_counter
;
50 unsigned label_counter
;
51 unsigned action_counter
;
52 bool probe_or_function_needs_deref_fault_handler
;
54 varuse_collecting_visitor vcv_needs_global_locks
;
56 map
<string
, string
> probe_contents
;
58 c_unparser (systemtap_session
* ss
):
59 session (ss
), o (ss
->op
), current_probe(0), current_function (0),
60 tmpvar_counter (0), label_counter (0) {}
63 void emit_map_type_instantiations ();
64 void emit_common_header ();
65 void emit_global (vardecl
* v
);
66 void emit_global_init (vardecl
* v
);
67 void emit_global_param (vardecl
* v
);
68 void emit_functionsig (functiondecl
* v
);
69 void emit_unprivileged_user_check ();
70 void emit_module_init ();
71 void emit_module_exit ();
72 void emit_function (functiondecl
* v
);
73 void emit_locks (const varuse_collecting_visitor
& v
);
74 void emit_probe (derived_probe
* v
);
75 void emit_unlocks (const varuse_collecting_visitor
& v
);
77 // for use by stats (pmap) foreach
78 set
<string
> aggregations_active
;
80 // for use by looping constructs
81 vector
<string
> loop_break_labels
;
82 vector
<string
> loop_continue_labels
;
84 string
c_typename (exp_type e
);
85 string
c_varname (const string
& e
);
86 string
c_expression (expression
* e
);
88 void c_assign (var
& lvalue
, const string
& rvalue
, const token
* tok
);
89 void c_assign (const string
& lvalue
, expression
* rvalue
, const string
& msg
);
90 void c_assign (const string
& lvalue
, const string
& rvalue
, exp_type type
,
91 const string
& msg
, const token
* tok
);
93 void c_declare(exp_type ty
, const string
&name
);
94 void c_declare_static(exp_type ty
, const string
&name
);
96 void c_strcat (const string
& lvalue
, const string
& rvalue
);
97 void c_strcat (const string
& lvalue
, expression
* rvalue
);
99 void c_strcpy (const string
& lvalue
, const string
& rvalue
);
100 void c_strcpy (const string
& lvalue
, expression
* rvalue
);
102 bool is_local (vardecl
const* r
, token
const* tok
);
104 tmpvar
gensym(exp_type ty
);
105 aggvar
gensym_aggregate();
107 var
getvar(vardecl
* v
, token
const* tok
= NULL
);
108 itervar
getiter(symbol
* s
);
109 mapvar
getmap(vardecl
* v
, token
const* tok
= NULL
);
111 void load_map_indices(arrayindex
* e
,
112 vector
<tmpvar
> & idx
);
114 void load_aggregate (expression
*e
, aggvar
& agg
, bool pre_agg
=false);
115 string
histogram_index_check(var
& vase
, tmpvar
& idx
) const;
117 void collect_map_index_types(vector
<vardecl
* > const & vars
,
118 set
< pair
<vector
<exp_type
>, exp_type
> > & types
);
120 void record_actions (unsigned actions
, bool update
=false);
122 void visit_block (block
* s
);
123 void visit_embeddedcode (embeddedcode
* s
);
124 void visit_null_statement (null_statement
* s
);
125 void visit_expr_statement (expr_statement
* s
);
126 void visit_if_statement (if_statement
* s
);
127 void visit_for_loop (for_loop
* s
);
128 void visit_foreach_loop (foreach_loop
* s
);
129 void visit_return_statement (return_statement
* s
);
130 void visit_delete_statement (delete_statement
* s
);
131 void visit_next_statement (next_statement
* s
);
132 void visit_break_statement (break_statement
* s
);
133 void visit_continue_statement (continue_statement
* s
);
134 void visit_literal_string (literal_string
* e
);
135 void visit_literal_number (literal_number
* e
);
136 void visit_binary_expression (binary_expression
* e
);
137 void visit_unary_expression (unary_expression
* e
);
138 void visit_pre_crement (pre_crement
* e
);
139 void visit_post_crement (post_crement
* e
);
140 void visit_logical_or_expr (logical_or_expr
* e
);
141 void visit_logical_and_expr (logical_and_expr
* e
);
142 void visit_array_in (array_in
* e
);
143 void visit_comparison (comparison
* e
);
144 void visit_concatenation (concatenation
* e
);
145 void visit_ternary_expression (ternary_expression
* e
);
146 void visit_assignment (assignment
* e
);
147 void visit_symbol (symbol
* e
);
148 void visit_target_symbol (target_symbol
* e
);
149 void visit_arrayindex (arrayindex
* e
);
150 void visit_functioncall (functioncall
* e
);
151 void visit_print_format (print_format
* e
);
152 void visit_stat_op (stat_op
* e
);
153 void visit_hist_op (hist_op
* e
);
154 void visit_cast_op (cast_op
* e
);
157 // A shadow visitor, meant to generate temporary variable declarations
158 // for function or probe bodies. Member functions should exactly match
159 // the corresponding c_unparser logic and traversal sequence,
160 // to ensure interlocking naming and declaration of temp variables.
162 public traversing_visitor
165 c_tmpcounter (c_unparser
* p
):
168 parent
->tmpvar_counter
= 0;
171 void load_map_indices(arrayindex
* e
);
173 void visit_block (block
*s
);
174 void visit_for_loop (for_loop
* s
);
175 void visit_foreach_loop (foreach_loop
* s
);
176 // void visit_return_statement (return_statement* s);
177 void visit_delete_statement (delete_statement
* s
);
178 void visit_binary_expression (binary_expression
* e
);
179 // void visit_unary_expression (unary_expression* e);
180 void visit_pre_crement (pre_crement
* e
);
181 void visit_post_crement (post_crement
* e
);
182 // void visit_logical_or_expr (logical_or_expr* e);
183 // void visit_logical_and_expr (logical_and_expr* e);
184 void visit_array_in (array_in
* e
);
185 // void visit_comparison (comparison* e);
186 void visit_concatenation (concatenation
* e
);
187 // void visit_ternary_expression (ternary_expression* e);
188 void visit_assignment (assignment
* e
);
189 void visit_arrayindex (arrayindex
* e
);
190 void visit_functioncall (functioncall
* e
);
191 void visit_print_format (print_format
* e
);
192 void visit_stat_op (stat_op
* e
);
195 struct c_unparser_assignment
:
196 public throwing_visitor
201 bool post
; // true == value saved before modify operator
202 c_unparser_assignment (c_unparser
* p
, const string
& o
, expression
* e
):
203 throwing_visitor ("invalid lvalue type"),
204 parent (p
), op (o
), rvalue (e
), post (false) {}
205 c_unparser_assignment (c_unparser
* p
, const string
& o
, bool pp
):
206 throwing_visitor ("invalid lvalue type"),
207 parent (p
), op (o
), rvalue (0), post (pp
) {}
209 void prepare_rvalue (string
const & op
,
213 void c_assignop(tmpvar
& res
,
218 // only symbols and arrayindex nodes are possible lvalues
219 void visit_symbol (symbol
* e
);
220 void visit_arrayindex (arrayindex
* e
);
224 struct c_tmpcounter_assignment
:
225 public traversing_visitor
226 // leave throwing for illegal lvalues to the c_unparser_assignment instance
228 c_tmpcounter
* parent
;
231 bool post
; // true == value saved before modify operator
232 c_tmpcounter_assignment (c_tmpcounter
* p
, const string
& o
, expression
* e
, bool pp
= false):
233 parent (p
), op (o
), rvalue (e
), post (pp
) {}
235 void prepare_rvalue (tmpvar
& rval
);
237 void c_assignop(tmpvar
& res
);
239 // only symbols and arrayindex nodes are possible lvalues
240 void visit_symbol (symbol
* e
);
241 void visit_arrayindex (arrayindex
* e
);
245 ostream
& operator<<(ostream
& o
, var
const & v
);
249 Some clarification on the runtime structures involved in statistics:
251 The basic type for collecting statistics in the runtime is struct
252 stat_data. This contains the count, min, max, sum, and possibly
255 There are two places struct stat_data shows up.
257 1. If you declare a statistic variable of any sort, you want to make
258 a struct _Stat. A struct _Stat* is also called a Stat. Struct _Stat
259 contains a per-CPU array of struct stat_data values, as well as a
260 struct stat_data which it aggregates into. Writes into a Struct
261 _Stat go into the per-CPU struct stat. Reads involve write-locking
262 the struct _Stat, aggregating into its aggregate struct stat_data,
263 unlocking, read-locking the struct _Stat, then reading values out of
264 the aggregate and unlocking.
266 2. If you declare a statistic-valued map, you want to make a
267 pmap. This is a per-CPU array of maps, each of which holds struct
268 stat_data values, as well as an aggregate *map*. Writes into a pmap
269 go into the per-CPU map. Reads involve write-locking the pmap,
270 aggregating into its aggregate map, unlocking, read-locking the
271 pmap, then reading values out of its aggregate (which is a normal
274 Because, at the moment, the runtime does not support the concept of
275 a statistic which collects multiple histogram types, we may need to
276 instantiate one pmap or struct _Stat for each histogram variation
277 the user wants to track.
291 var(bool local
, exp_type ty
, statistic_decl
const & sd
, string
const & name
)
292 : local(local
), ty(ty
), sd(sd
), name(name
)
295 var(bool local
, exp_type ty
, string
const & name
)
296 : local(local
), ty(ty
), name(name
)
301 bool is_local() const
306 statistic_decl
const & sdecl() const
311 void assert_hist_compatible(hist_op
const & hop
)
313 // Semantic checks in elaborate should have caught this if it was
314 // false. This is just a double-check.
317 case statistic_decl::linear
:
318 assert(hop
.htype
== hist_linear
);
319 assert(hop
.params
.size() == 3);
320 assert(hop
.params
[0] == sd
.linear_low
);
321 assert(hop
.params
[1] == sd
.linear_high
);
322 assert(hop
.params
[2] == sd
.linear_step
);
324 case statistic_decl::logarithmic
:
325 assert(hop
.htype
== hist_log
);
326 assert(hop
.params
.size() == 0);
328 case statistic_decl::none
:
333 exp_type
type() const
343 return "global.s_" + name
;
346 virtual string
hist() const
348 assert (ty
== pe_stats
);
349 assert (sd
.type
!= statistic_decl::none
);
350 return "(&(" + value() + "->hist))";
353 virtual string
buckets() const
355 assert (ty
== pe_stats
);
356 assert (sd
.type
!= statistic_decl::none
);
357 return "(" + value() + "->hist.buckets)";
366 return ""; // module_param
368 return value() + "[0] = '\\0';";
371 return ""; // module_param
373 return value() + " = 0;";
376 // See also mapvar::init().
378 string prefix
= value() + " = _stp_stat_init (";
379 // Check for errors during allocation.
380 string suffix
= "if (" + value () + " == NULL) rc = -ENOMEM;";
384 case statistic_decl::none
:
385 prefix
+= "HIST_NONE";
388 case statistic_decl::linear
:
389 prefix
+= string("HIST_LINEAR")
390 + ", " + stringify(sd
.linear_low
)
391 + ", " + stringify(sd
.linear_high
)
392 + ", " + stringify(sd
.linear_step
);
395 case statistic_decl::logarithmic
:
396 prefix
+= string("HIST_LOG");
400 throw semantic_error("unsupported stats type for " + value());
403 prefix
= prefix
+ "); ";
404 return string (prefix
+ suffix
);
408 throw semantic_error("unsupported initializer for " + value());
418 return ""; // no action required
420 return "_stp_stat_del (" + value () + ");";
422 throw semantic_error("unsupported deallocator for " + value());
426 void declare(c_unparser
&c
) const
428 c
.c_declare(ty
, name
);
432 ostream
& operator<<(ostream
& o
, var
const & v
)
434 return o
<< v
.value();
440 stmt_expr(c_unparser
& c
) : c(c
)
442 c
.o
->newline() << "({";
447 c
.o
->newline(-1) << "})";
457 string override_value
;
462 : var(true, ty
, ("__tmp" + stringify(counter
++))), overridden(false)
465 tmpvar(const var
& source
)
466 : var(source
), overridden(false)
469 void override(const string
&value
)
472 override_value
= value
;
478 return override_value
;
484 ostream
& operator<<(ostream
& o
, tmpvar
const & v
)
486 return o
<< v
.value();
492 aggvar(unsigned & counter
)
493 : var(true, pe_stats
, ("__tmp" + stringify(counter
++)))
498 assert (type() == pe_stats
);
499 return value() + " = NULL;";
502 void declare(c_unparser
&c
) const
504 assert (type() == pe_stats
);
505 c
.o
->newline() << "struct stat_data *" << name
<< ";";
512 vector
<exp_type
> index_types
;
514 mapvar (bool local
, exp_type ty
,
515 statistic_decl
const & sd
,
517 vector
<exp_type
> const & index_types
,
519 : var (local
, ty
, sd
, name
),
520 index_types (index_types
),
524 static string
shortname(exp_type e
);
525 static string
key_typename(exp_type e
);
526 static string
value_typename(exp_type e
);
528 string
keysym () const
531 vector
<exp_type
> tmp
= index_types
;
532 tmp
.push_back (type ());
533 for (unsigned i
= 0; i
< tmp
.size(); ++i
)
547 throw semantic_error("unknown type of map");
554 string
call_prefix (string
const & fname
, vector
<tmpvar
> const & indices
, bool pre_agg
=false) const
556 string mtype
= (is_parallel() && !pre_agg
) ? "pmap" : "map";
557 string result
= "_stp_" + mtype
+ "_" + fname
+ "_" + keysym() + " (";
558 result
+= pre_agg
? fetch_existing_aggregate() : value();
559 for (unsigned i
= 0; i
< indices
.size(); ++i
)
561 if (indices
[i
].type() != index_types
[i
])
562 throw semantic_error("index type mismatch");
564 result
+= indices
[i
].value();
570 bool is_parallel() const
572 return type() == pe_stats
;
575 string
calculate_aggregate() const
578 throw semantic_error("aggregating non-parallel map type");
580 return "_stp_pmap_agg (" + value() + ")";
583 string
fetch_existing_aggregate() const
586 throw semantic_error("fetching aggregate of non-parallel map type");
588 return "_stp_pmap_get_agg(" + value() + ")";
591 string
del (vector
<tmpvar
> const & indices
) const
593 return (call_prefix("del", indices
) + ")");
596 string
exists (vector
<tmpvar
> const & indices
) const
598 if (type() == pe_long
|| type() == pe_string
)
599 return (call_prefix("exists", indices
) + ")");
600 else if (type() == pe_stats
)
601 return ("((uintptr_t)" + call_prefix("get", indices
)
602 + ") != (uintptr_t) 0)");
604 throw semantic_error("checking existence of an unsupported map type");
607 string
get (vector
<tmpvar
> const & indices
, bool pre_agg
=false) const
609 // see also itervar::get_key
610 if (type() == pe_string
)
611 // impedance matching: NULL -> empty strings
612 return ("({ char *v = " + call_prefix("get", indices
, pre_agg
) + ");"
613 + "if (!v) v = \"\"; v; })");
614 else if (type() == pe_long
|| type() == pe_stats
)
615 return call_prefix("get", indices
, pre_agg
) + ")";
617 throw semantic_error("getting a value from an unsupported map type");
620 string
add (vector
<tmpvar
> const & indices
, tmpvar
const & val
) const
622 string res
= "{ int rc = ";
624 // impedance matching: empty strings -> NULL
625 if (type() == pe_stats
)
626 res
+= (call_prefix("add", indices
) + ", " + val
.value() + ")");
628 throw semantic_error("adding a value of an unsupported map type");
630 res
+= "; if (unlikely(rc)) { c->last_error = \"Array overflow, check " +
631 stringify(maxsize
> 0 ?
632 "size limit (" + stringify(maxsize
) + ")" : "MAXMAPENTRIES")
633 + "\"; goto out; }}";
638 string
set (vector
<tmpvar
> const & indices
, tmpvar
const & val
) const
640 string res
= "{ int rc = ";
642 // impedance matching: empty strings -> NULL
643 if (type() == pe_string
)
644 res
+= (call_prefix("set", indices
)
645 + ", (" + val
.value() + "[0] ? " + val
.value() + " : NULL))");
646 else if (type() == pe_long
)
647 res
+= (call_prefix("set", indices
) + ", " + val
.value() + ")");
649 throw semantic_error("setting a value of an unsupported map type");
651 res
+= "; if (unlikely(rc)) { c->last_error = \"Array overflow, check " +
652 stringify(maxsize
> 0 ?
653 "size limit (" + stringify(maxsize
) + ")" : "MAXMAPENTRIES")
654 + "\"; goto out; }}";
661 assert (ty
== pe_stats
);
662 assert (sd
.type
!= statistic_decl::none
);
663 return "(&(" + fetch_existing_aggregate() + "->hist))";
666 string
buckets() const
668 assert (ty
== pe_stats
);
669 assert (sd
.type
!= statistic_decl::none
);
670 return "(" + fetch_existing_aggregate() + "->hist.buckets)";
675 string mtype
= is_parallel() ? "pmap" : "map";
676 string prefix
= value() + " = _stp_" + mtype
+ "_new_" + keysym() + " (" +
677 (maxsize
> 0 ? stringify(maxsize
) : "MAXMAPENTRIES") ;
679 // See also var::init().
681 // Check for errors during allocation.
682 string suffix
= "if (" + value () + " == NULL) rc = -ENOMEM;";
684 if (type() == pe_stats
)
686 switch (sdecl().type
)
688 case statistic_decl::none
:
689 prefix
= prefix
+ ", HIST_NONE";
692 case statistic_decl::linear
:
693 // FIXME: check for "reasonable" values in linear stats
694 prefix
= prefix
+ ", HIST_LINEAR"
695 + ", " + stringify(sdecl().linear_low
)
696 + ", " + stringify(sdecl().linear_high
)
697 + ", " + stringify(sdecl().linear_step
);
700 case statistic_decl::logarithmic
:
701 prefix
= prefix
+ ", HIST_LOG";
706 prefix
= prefix
+ "); ";
707 return (prefix
+ suffix
);
712 // NB: fini() is safe to call even for globals that have not
713 // successfully initialized (that is to say, on NULL pointers),
714 // because the runtime specifically tolerates that in its _del
718 return "_stp_pmap_del (" + value() + ");";
720 return "_stp_map_del (" + value() + ");";
727 exp_type referent_ty
;
732 itervar (symbol
* e
, unsigned & counter
)
733 : referent_ty(e
->referent
->type
),
734 name("__tmp" + stringify(counter
++))
736 if (referent_ty
== pe_unknown
)
737 throw semantic_error("iterating over unknown reference type", e
->tok
);
740 string
declare () const
742 return "struct map_node *" + name
+ ";";
745 string
start (mapvar
const & mv
) const
749 if (mv
.type() != referent_ty
)
750 throw semantic_error("inconsistent iterator type in itervar::start()");
752 if (mv
.is_parallel())
753 return "_stp_map_start (" + mv
.fetch_existing_aggregate() + ")";
755 return "_stp_map_start (" + mv
.value() + ")";
758 string
next (mapvar
const & mv
) const
760 if (mv
.type() != referent_ty
)
761 throw semantic_error("inconsistent iterator type in itervar::next()");
763 if (mv
.is_parallel())
764 return "_stp_map_iter (" + mv
.fetch_existing_aggregate() + ", " + value() + ")";
766 return "_stp_map_iter (" + mv
.value() + ", " + value() + ")";
769 string
value () const
774 string
get_key (exp_type ty
, unsigned i
) const
776 // bug translator/1175: runtime uses base index 1 for the first dimension
777 // see also mapval::get
781 return "_stp_key_get_int64 ("+ value() + ", " + stringify(i
+1) + ")";
783 // impedance matching: NULL -> empty strings
784 return "({ char *v = "
785 "_stp_key_get_str ("+ value() + ", " + stringify(i
+1) + "); "
786 "if (! v) v = \"\"; "
789 throw semantic_error("illegal key type");
794 ostream
& operator<<(ostream
& o
, itervar
const & v
)
796 return o
<< v
.value();
799 // ------------------------------------------------------------------------
802 translator_output::translator_output (ostream
& f
):
803 buf(0), o2 (0), o (f
), tablevel (0)
808 translator_output::translator_output (const string
& filename
, size_t bufsize
):
809 buf (new char[bufsize
]),
810 o2 (new ofstream (filename
.c_str ())),
814 o2
->rdbuf()->pubsetbuf(buf
, bufsize
);
818 translator_output::~translator_output ()
826 translator_output::newline (int indent
)
828 if (! (indent
> 0 || tablevel
>= (unsigned)-indent
)) o
.flush ();
829 assert (indent
> 0 || tablevel
>= (unsigned)-indent
);
833 for (unsigned i
=0; i
<tablevel
; i
++)
840 translator_output::indent (int indent
)
842 if (! (indent
> 0 || tablevel
>= (unsigned)-indent
)) o
.flush ();
843 assert (indent
> 0 || tablevel
>= (unsigned)-indent
);
849 translator_output::line ()
855 // ------------------------------------------------------------------------
858 c_unparser::emit_common_header ()
861 o
->newline() << "typedef char string_t[MAXSTRINGLEN];";
863 o
->newline() << "#define STAP_SESSION_STARTING 0";
864 o
->newline() << "#define STAP_SESSION_RUNNING 1";
865 o
->newline() << "#define STAP_SESSION_ERROR 2";
866 o
->newline() << "#define STAP_SESSION_STOPPING 3";
867 o
->newline() << "#define STAP_SESSION_STOPPED 4";
868 o
->newline() << "static atomic_t session_state = ATOMIC_INIT (STAP_SESSION_STARTING);";
869 o
->newline() << "static atomic_t error_count = ATOMIC_INIT (0);";
870 o
->newline() << "static atomic_t skipped_count = ATOMIC_INIT (0);";
871 o
->newline() << "static atomic_t skipped_count_lowstack = ATOMIC_INIT (0);";
872 o
->newline() << "static atomic_t skipped_count_reentrant = ATOMIC_INIT (0);";
873 o
->newline() << "static atomic_t skipped_count_uprobe_reg = ATOMIC_INIT (0);";
874 o
->newline() << "static atomic_t skipped_count_uprobe_unreg = ATOMIC_INIT (0);";
876 o
->newline() << "struct context {";
877 o
->newline(1) << "atomic_t busy;";
878 o
->newline() << "const char *probe_point;";
879 o
->newline() << "int actionremaining;";
880 o
->newline() << "unsigned nesting;";
881 o
->newline() << "string_t error_buffer;";
882 o
->newline() << "const char *last_error;";
883 // NB: last_error is used as a health flag within a probe.
884 // While it's 0, execution continues
885 // When it's "something", probe code unwinds, _stp_error's, sets error state
886 o
->newline() << "const char *last_stmt;";
887 o
->newline() << "struct pt_regs *regs;";
888 o
->newline() << "unsigned long *unwaddr;";
889 // unwaddr is caching unwound address in each probe handler on ia64.
890 o
->newline() << "struct kretprobe_instance *pi;";
891 o
->newline() << "int regparm;";
892 o
->newline() << "va_list *mark_va_list;";
893 o
->newline() << "const char * marker_name;";
894 o
->newline() << "const char * marker_format;";
895 o
->newline() << "void *data;";
896 o
->newline() << "#ifdef STP_TIMING";
897 o
->newline() << "Stat *statp;";
898 o
->newline() << "#endif";
899 o
->newline() << "#ifdef STP_OVERLOAD";
900 o
->newline() << "cycles_t cycles_base;";
901 o
->newline() << "cycles_t cycles_sum;";
902 o
->newline() << "#endif";
903 o
->newline() << "union {";
906 // To elide context variables for probe handler functions that
907 // themselves are about to get duplicate-eliminated, we XXX
908 // duplicate the parse-tree-hash method from ::emit_probe().
909 map
<string
, string
> tmp_probe_contents
;
910 // The reason we don't use c_unparser::probe_contents itself
911 // for this is that we don't want to muck up the data for
912 // that later routine.
914 for (unsigned i
=0; i
<session
->probes
.size(); i
++)
916 derived_probe
* dp
= session
->probes
[i
];
918 // NB: see c_unparser::emit_probe() for original copy of duplicate-hashing logic.
920 oss
<< "c->statp = & time_" << dp
->basest()->name
<< ";" << endl
; // -t anti-dupe
921 oss
<< "# needs_global_locks: " << dp
->needs_global_locks () << endl
;
922 dp
->print_dupe_stamp (oss
);
923 dp
->body
->print(oss
);
924 // NB: dependent probe conditions *could* be listed here, but don't need to be.
925 // That's because they're only dependent on the probe body, which is already
926 // "hashed" in above.
929 if (tmp_probe_contents
.count(oss
.str()) == 0) // unique
931 tmp_probe_contents
[oss
.str()] = dp
->name
; // save it
933 // XXX: probe locals need not be recursion-nested, only function locals
935 o
->newline() << "struct " << dp
->name
<< "_locals {";
937 for (unsigned j
=0; j
<dp
->locals
.size(); j
++)
939 vardecl
* v
= dp
->locals
[j
];
942 o
->newline() << c_typename (v
->type
) << " "
943 << c_varname (v
->name
) << ";";
944 } catch (const semantic_error
& e
) {
945 semantic_error
e2 (e
);
946 if (e2
.tok1
== 0) e2
.tok1
= v
->tok
;
951 // NB: This part is finicky. The logic here must
953 c_tmpcounter
ct (this);
954 dp
->emit_probe_context_vars (o
);
955 dp
->body
->visit (& ct
);
957 o
->newline(-1) << "} " << dp
->name
<< ";";
961 for (map
<string
,functiondecl
*>::iterator it
= session
->functions
.begin(); it
!= session
->functions
.end(); it
++)
963 functiondecl
* fd
= it
->second
;
965 << "struct function_" << c_varname (fd
->name
) << "_locals {";
967 for (unsigned j
=0; j
<fd
->locals
.size(); j
++)
969 vardecl
* v
= fd
->locals
[j
];
972 o
->newline() << c_typename (v
->type
) << " "
973 << c_varname (v
->name
) << ";";
974 } catch (const semantic_error
& e
) {
975 semantic_error
e2 (e
);
976 if (e2
.tok1
== 0) e2
.tok1
= v
->tok
;
980 for (unsigned j
=0; j
<fd
->formal_args
.size(); j
++)
982 vardecl
* v
= fd
->formal_args
[j
];
985 o
->newline() << c_typename (v
->type
) << " "
986 << c_varname (v
->name
) << ";";
987 } catch (const semantic_error
& e
) {
988 semantic_error
e2 (e
);
989 if (e2
.tok1
== 0) e2
.tok1
= v
->tok
;
993 c_tmpcounter
ct (this);
994 fd
->body
->visit (& ct
);
995 if (fd
->type
== pe_unknown
)
996 o
->newline() << "/* no return value */";
999 o
->newline() << c_typename (fd
->type
) << " __retvalue;";
1001 o
->newline(-1) << "} function_" << c_varname (fd
->name
) << ";";
1003 o
->newline(-1) << "} locals [MAXNESTING];";
1004 o
->newline(-1) << "};\n";
1005 o
->newline() << "static void *contexts = NULL; /* alloc_percpu */\n";
1007 emit_map_type_instantiations ();
1009 if (!session
->stat_decls
.empty())
1010 o
->newline() << "#include \"stat.c\"\n";
1017 c_unparser::emit_global_param (vardecl
*v
)
1019 string vn
= c_varname (v
->name
);
1021 // NB: systemtap globals can collide with linux macros,
1022 // e.g. VM_FAULT_MAJOR. We want the parameter name anyway. This
1023 // #undef is spit out at the end of the C file, so that removing the
1024 // definition won't affect any other embedded-C or generated code.
1025 // XXX: better not have a global variable named module_param_named etc.!
1026 o
->newline() << "#undef " << vn
;
1028 // Emit module_params for this global, if its type is convenient.
1029 if (v
->arity
== 0 && v
->type
== pe_long
)
1031 o
->newline() << "module_param_named (" << vn
<< ", "
1032 << "global.s_" << vn
<< ", int64_t, 0);";
1034 else if (v
->arity
== 0 && v
->type
== pe_string
)
1036 // NB: no special copying is needed.
1037 o
->newline() << "module_param_string (" << vn
<< ", "
1038 << "global.s_" << vn
1039 << ", MAXSTRINGLEN, 0);";
1045 c_unparser::emit_global (vardecl
*v
)
1047 string vn
= c_varname (v
->name
);
1050 o
->newline() << c_typename (v
->type
) << " s_" << vn
<< ";";
1051 else if (v
->type
== pe_stats
)
1052 o
->newline() << "PMAP s_" << vn
<< ";";
1054 o
->newline() << "MAP s_" << vn
<< ";";
1055 o
->newline() << "rwlock_t s_" << vn
<< "_lock;";
1056 o
->newline() << "#ifdef STP_TIMING";
1057 o
->newline() << "atomic_t s_" << vn
<< "_lock_skip_count;";
1058 o
->newline() << "#endif\n";
1063 c_unparser::emit_global_init (vardecl
*v
)
1065 string vn
= c_varname (v
->name
);
1067 if (v
->arity
== 0) // can only statically initialize some scalars
1071 o
->newline() << ".s_" << vn
<< " = ";
1072 v
->init
->visit(this);
1076 o
->newline() << "#ifdef STP_TIMING";
1077 o
->newline() << ".s_" << vn
<< "_lock_skip_count = ATOMIC_INIT(0),";
1078 o
->newline() << "#endif";
1084 c_unparser::emit_functionsig (functiondecl
* v
)
1086 o
->newline() << "static void function_" << v
->name
1087 << " (struct context * __restrict__ c);";
1092 c_unparser::emit_unprivileged_user_check ()
1094 // If the --unprivileged option was specified then the module
1095 // will be safe for unprivileged users, if it is successfully generated,
1096 // so no check need be emitted.
1097 if (session
->unprivileged
)
1100 // Otherwise, generate code to check whether the user is unprivileged.
1101 // If so, then generate an error and indicate that the check has failed.
1103 o
->newline() << "static int systemtap_unprivileged_user_check (void) {";
1104 o
->newline(1) << "if (! _stp_unprivileged_user)";
1105 o
->newline(1) << "return 0;";
1107 o
->newline(-1) << "_stp_error (\"You are attempting to run stap as an ordinary user.\");";
1108 o
->newline() << "_stp_error (\"Your module must be compiled using the --unprivileged option.\");";
1109 o
->newline() << "return 1;";
1111 o
->newline(-1) << "}\n";
1116 c_unparser::emit_module_init ()
1118 vector
<derived_probe_group
*> g
= all_session_groups (*session
);
1119 for (unsigned i
=0; i
<g
.size(); i
++)
1120 g
[i
]->emit_module_decls (*session
);
1123 o
->newline() << "static int systemtap_module_init (void) {";
1124 o
->newline(1) << "int rc = 0;";
1125 o
->newline() << "int i=0, j=0;"; // for derived_probe_group use
1126 o
->newline() << "const char *probe_point = \"\";";
1128 // Compare actual and targeted kernel releases/machines. Sometimes
1129 // one may install the incorrect debuginfo or -devel RPM, and try to
1130 // run a probe compiled for a different version. Catch this early,
1131 // just in case modversions didn't.
1132 o
->newline() << "{";
1133 o
->newline(1) << "const char* release = UTS_RELEASE;";
1135 // NB: This UTS_RELEASE compile-time macro directly checks only that
1136 // the compile-time kbuild tree matches the compile-time debuginfo/etc.
1137 // It does not check the run time kernel value. However, this is
1138 // probably OK since the kbuild modversions system aims to prevent
1139 // mismatches between kbuild and runtime versions at module-loading time.
1141 // o->newline() << "const char* machine = UTS_MACHINE;";
1142 // NB: We could compare UTS_MACHINE too, but on x86 it lies
1143 // (UTS_MACHINE=i386, but uname -m is i686). Sheesh.
1145 o
->newline() << "if (strcmp (release, "
1146 << lex_cast_qstring (session
->kernel_release
) << ")) {";
1147 o
->newline(1) << "_stp_error (\"module release mismatch (%s vs %s)\", "
1149 << lex_cast_qstring (session
->kernel_release
)
1151 o
->newline() << "rc = -EINVAL;";
1152 o
->newline(-1) << "}";
1154 // perform buildid-based checking if able
1155 o
->newline() << "if (_stp_module_check()) rc = -EINVAL;";
1157 o
->newline(-1) << "}";
1159 if (! session
->unprivileged
) {
1160 // Check whether the user is unprivileged.
1161 o
->newline() << "if (systemtap_unprivileged_user_check ()) rc = -EINVAL;";
1164 o
->newline() << "if (rc) goto out;";
1166 o
->newline() << "(void) probe_point;";
1167 o
->newline() << "(void) i;";
1168 o
->newline() << "(void) j;";
1169 o
->newline() << "atomic_set (&session_state, STAP_SESSION_STARTING);";
1170 // This signals any other probes that may be invoked in the next little
1171 // while to abort right away. Currently running probes are allowed to
1172 // terminate. These may set STAP_SESSION_ERROR!
1175 o
->newline() << "if (sizeof (struct context) <= 131072)";
1176 o
->newline(1) << "contexts = alloc_percpu (struct context);";
1177 o
->newline(-1) << "if (contexts == NULL) {";
1178 o
->newline(1) << "_stp_error (\"percpu context (size %lu) allocation failed\", sizeof (struct context));";
1179 o
->newline() << "rc = -ENOMEM;";
1180 o
->newline() << "goto out;";
1181 o
->newline(-1) << "}";
1183 for (unsigned i
=0; i
<session
->globals
.size(); i
++)
1185 vardecl
* v
= session
->globals
[i
];
1186 if (v
->index_types
.size() > 0)
1187 o
->newline() << getmap (v
).init();
1189 o
->newline() << getvar (v
).init();
1190 // NB: in case of failure of allocation, "rc" will be set to non-zero.
1191 // Allocation can in general continue.
1193 o
->newline() << "if (rc) {";
1194 o
->newline(1) << "_stp_error (\"global variable " << v
->name
<< " allocation failed\");";
1195 o
->newline() << "goto out;";
1196 o
->newline(-1) << "}";
1198 o
->newline() << "rwlock_init (& global.s_" << c_varname (v
->name
) << "_lock);";
1201 // initialize each Stat used for timing information
1202 o
->newline() << "#ifdef STP_TIMING";
1203 set
<string
> basest_names
;
1204 for (unsigned i
=0; i
<session
->probes
.size(); i
++)
1206 string nm
= session
->probes
[i
]->basest()->name
;
1207 if (basest_names
.find(nm
) == basest_names
.end())
1209 o
->newline() << "time_" << nm
<< " = _stp_stat_init (HIST_NONE);";
1210 // NB: we don't check for null return here, but instead at
1211 // passage to probe handlers and at final printing.
1212 basest_names
.insert (nm
);
1215 o
->newline() << "#endif";
1217 // Print a message to the kernel log about this module. This is
1218 // intended to help debug problems with systemtap modules.
1220 o
->newline() << "_stp_print_kernel_info("
1222 << "/" << dwfl_version (NULL
) << "\""
1223 << ", (num_online_cpus() * sizeof(struct context))"
1224 << ", " << session
->probes
.size()
1227 // Run all probe registrations. This actually runs begin probes.
1229 for (unsigned i
=0; i
<g
.size(); i
++)
1231 g
[i
]->emit_module_init (*session
);
1232 // NB: this gives O(N**2) amount of code, but luckily there
1233 // are only seven or eight derived_probe_groups, so it's ok.
1234 o
->newline() << "if (rc) {";
1235 o
->newline(1) << "_stp_error (\"probe %s registration error (rc %d)\", probe_point, rc);";
1236 // NB: we need to be in the error state so timers can shutdown cleanly,
1237 // and so end probes don't run. OTOH, error probes can run.
1238 o
->newline() << "atomic_set (&session_state, STAP_SESSION_ERROR);";
1240 for (int j
=i
-1; j
>=0; j
--)
1241 g
[j
]->emit_module_exit (*session
);
1242 o
->newline() << "goto out;";
1243 o
->newline(-1) << "}";
1246 // All registrations were successful. Consider the system started.
1247 o
->newline() << "if (atomic_read (&session_state) == STAP_SESSION_STARTING)";
1248 // NB: only other valid state value is ERROR, in which case we don't
1249 o
->newline(1) << "atomic_set (&session_state, STAP_SESSION_RUNNING);";
1250 o
->newline(-1) << "return 0;";
1252 // Error handling path; by now all partially registered probe groups
1253 // have been unregistered.
1254 o
->newline(-1) << "out:";
1257 // If any registrations failed, we will need to deregister the globals,
1258 // as this is our only chance.
1259 for (unsigned i
=0; i
<session
->globals
.size(); i
++)
1261 vardecl
* v
= session
->globals
[i
];
1262 if (v
->index_types
.size() > 0)
1263 o
->newline() << getmap (v
).fini();
1265 o
->newline() << getvar (v
).fini();
1268 // For any partially registered/unregistered kernel facilities.
1269 o
->newline() << "#ifdef STAPCONF_SYNCHRONIZE_SCHED";
1270 o
->newline() << "synchronize_sched();";
1271 o
->newline() << "#endif";
1273 o
->newline() << "return rc;";
1274 o
->newline(-1) << "}\n";
1279 c_unparser::emit_module_exit ()
1281 o
->newline() << "static void systemtap_module_exit (void) {";
1283 o
->newline(1) << "int holdon;";
1284 o
->newline() << "int i=0, j=0;"; // for derived_probe_group use
1286 o
->newline() << "(void) i;";
1287 o
->newline() << "(void) j;";
1288 // If we aborted startup, then everything has been cleaned up already, and
1289 // module_exit shouldn't even have been called. But since it might be, let's
1290 // beat a hasty retreat to avoid double uninitialization.
1291 o
->newline() << "if (atomic_read (&session_state) == STAP_SESSION_STARTING)";
1292 o
->newline(1) << "return;";
1295 o
->newline() << "if (atomic_read (&session_state) == STAP_SESSION_RUNNING)";
1296 // NB: only other valid state value is ERROR, in which case we don't
1297 o
->newline(1) << "atomic_set (&session_state, STAP_SESSION_STOPPING);";
1299 // This signals any other probes that may be invoked in the next little
1300 // while to abort right away. Currently running probes are allowed to
1301 // terminate. These may set STAP_SESSION_ERROR!
1303 // We're processing the derived_probe_group list in reverse
1304 // order. This ensures that probes get unregistered in reverse
1305 // order of the way they were registered.
1306 vector
<derived_probe_group
*> g
= all_session_groups (*session
);
1307 for (vector
<derived_probe_group
*>::reverse_iterator i
= g
.rbegin();
1309 (*i
)->emit_module_exit (*session
); // NB: runs "end" probes
1311 // But some other probes may have launched too during unregistration.
1312 // Let's wait a while to make sure they're all done, done, done.
1314 // cargo cult prologue
1315 o
->newline() << "#ifdef STAPCONF_SYNCHRONIZE_SCHED";
1316 o
->newline() << "synchronize_sched();";
1317 o
->newline() << "#endif";
1319 // NB: systemtap_module_exit is assumed to be called from ordinary
1320 // user context, say during module unload. Among other things, this
1321 // means we can sleep a while.
1322 o
->newline() << "do {";
1323 o
->newline(1) << "int i;";
1324 o
->newline() << "holdon = 0;";
1325 o
->newline() << "for (i=0; i < NR_CPUS; i++)";
1326 o
->newline(1) << "if (cpu_possible (i) && "
1327 << "atomic_read (& ((struct context *)per_cpu_ptr(contexts, i))->busy)) "
1329 // NB: we run at least one of these during the shutdown sequence:
1330 o
->newline () << "yield ();"; // aka schedule() and then some
1331 o
->newline(-2) << "} while (holdon);";
1333 // cargo cult epilogue
1334 o
->newline() << "#ifdef STAPCONF_SYNCHRONIZE_SCHED";
1335 o
->newline() << "synchronize_sched();";
1336 o
->newline() << "#endif";
1338 // XXX: might like to have an escape hatch, in case some probe is
1339 // genuinely stuck somehow
1341 for (unsigned i
=0; i
<session
->globals
.size(); i
++)
1343 vardecl
* v
= session
->globals
[i
];
1344 if (v
->index_types
.size() > 0)
1345 o
->newline() << getmap (v
).fini();
1347 o
->newline() << getvar (v
).fini();
1350 o
->newline() << "free_percpu (contexts);";
1352 // print probe timing statistics
1354 o
->newline() << "#ifdef STP_TIMING";
1355 o
->newline() << "{";
1357 set
<string
> basest_names
;
1358 for (unsigned i
=0; i
<session
->probes
.size(); i
++)
1360 probe
* p
= session
->probes
[i
]->basest();
1361 string nm
= p
->name
;
1362 if (basest_names
.find(nm
) == basest_names
.end())
1364 basest_names
.insert (nm
);
1365 // NB: check for null stat object
1366 o
->newline() << "if (likely (time_" << p
->name
<< ")) {";
1367 o
->newline(1) << "const char *probe_point = "
1368 << lex_cast_qstring (* p
->locations
[0])
1369 << (p
->locations
.size() > 1 ? "\"+\"" : "")
1370 << (p
->locations
.size() > 1 ? lex_cast_qstring(p
->locations
.size()-1) : "")
1372 o
->newline() << "const char *decl_location = "
1373 << lex_cast_qstring (p
->tok
->location
)
1375 o
->newline() << "struct stat_data *stats = _stp_stat_get (time_"
1378 o
->newline() << "if (stats->count) {";
1379 o
->newline(1) << "int64_t avg = _stp_div64 (NULL, stats->sum, stats->count);";
1380 o
->newline() << "_stp_printf (\"probe %s (%s), hits: %lld, cycles: %lldmin/%lldavg/%lldmax\\n\",";
1381 o
->newline() << "probe_point, decl_location, (long long) stats->count, (long long) stats->min, (long long) avg, (long long) stats->max);";
1382 o
->newline(-1) << "}";
1383 o
->newline() << "_stp_stat_del (time_" << p
->name
<< ");";
1384 o
->newline(-1) << "}";
1387 o
->newline() << "_stp_print_flush();";
1388 o
->newline(-1) << "}";
1389 o
->newline() << "#endif";
1392 // print final error/skipped counts if non-zero
1393 o
->newline() << "if (atomic_read (& skipped_count) || "
1394 << "atomic_read (& error_count) || "
1395 << "atomic_read (& skipped_count_reentrant)) {"; // PR9967
1396 o
->newline(1) << "_stp_warn (\"Number of errors: %d, "
1397 << "skipped probes: %d\\n\", "
1398 << "(int) atomic_read (& error_count), "
1399 << "(int) atomic_read (& skipped_count));";
1400 o
->newline() << "#ifdef STP_TIMING";
1401 o
->newline() << "{";
1402 o
->newline(1) << "int ctr;";
1403 for (unsigned i
=0; i
<session
->globals
.size(); i
++)
1405 string vn
= c_varname (session
->globals
[i
]->name
);
1406 o
->newline() << "ctr = atomic_read (& global.s_" << vn
<< "_lock_skip_count);";
1407 o
->newline() << "if (ctr) _stp_warn (\"Skipped due to global '%s' lock timeout: %d\\n\", "
1408 << lex_cast_qstring(vn
) << ", ctr);";
1410 o
->newline() << "ctr = atomic_read (& skipped_count_lowstack);";
1411 o
->newline() << "if (ctr) _stp_warn (\"Skipped due to low stack: %d\\n\", ctr);";
1412 o
->newline() << "ctr = atomic_read (& skipped_count_reentrant);";
1413 o
->newline() << "if (ctr) _stp_warn (\"Skipped due to reentrancy: %d\\n\", ctr);";
1414 o
->newline() << "ctr = atomic_read (& skipped_count_uprobe_reg);";
1415 o
->newline() << "if (ctr) _stp_warn (\"Skipped due to uprobe register failure: %d\\n\", ctr);";
1416 o
->newline() << "ctr = atomic_read (& skipped_count_uprobe_unreg);";
1417 o
->newline() << "if (ctr) _stp_warn (\"Skipped due to uprobe unregister failure: %d\\n\", ctr);";
1418 o
->newline(-1) << "}";
1419 o
->newline () << "#endif";
1420 o
->newline() << "_stp_print_flush();";
1421 o
->newline(-1) << "}";
1422 o
->newline(-1) << "}\n";
1427 c_unparser::emit_function (functiondecl
* v
)
1429 o
->newline() << "static void function_" << c_varname (v
->name
)
1430 << " (struct context* __restrict__ c) {";
1432 this->current_probe
= 0;
1433 this->current_function
= v
;
1434 this->tmpvar_counter
= 0;
1435 this->action_counter
= 0;
1438 << "struct function_" << c_varname (v
->name
) << "_locals * "
1439 << " __restrict__ l =";
1441 << "& c->locals[c->nesting+1].function_" << c_varname (v
->name
) // NB: nesting+1
1443 o
->newline(-1) << "(void) l;"; // make sure "l" is marked used
1444 o
->newline() << "#define CONTEXT c";
1445 o
->newline() << "#define THIS l";
1446 o
->newline() << "if (0) goto out;"; // make sure out: is marked used
1448 // set this, in case embedded-c code sets last_error but doesn't otherwise identify itself
1449 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*v
->tok
) << ";";
1451 // check/increment nesting level
1452 o
->newline() << "if (unlikely (c->nesting+2 >= MAXNESTING)) {";
1453 o
->newline(1) << "c->last_error = \"MAXNESTING exceeded\";";
1454 o
->newline() << "return;";
1455 o
->newline(-1) << "} else {";
1456 o
->newline(1) << "c->nesting ++;";
1457 o
->newline(-1) << "}";
1459 // initialize locals
1460 // XXX: optimization: use memset instead
1461 for (unsigned i
=0; i
<v
->locals
.size(); i
++)
1463 if (v
->locals
[i
]->index_types
.size() > 0) // array?
1464 throw semantic_error ("array locals not supported, missing global declaration?",
1467 o
->newline() << getvar (v
->locals
[i
]).init();
1470 // initialize return value, if any
1471 if (v
->type
!= pe_unknown
)
1473 var retvalue
= var(true, v
->type
, "__retvalue");
1474 o
->newline() << retvalue
.init();
1477 o
->newline() << "#define return goto out"; // redirect embedded-C return
1478 this->probe_or_function_needs_deref_fault_handler
= false;
1479 v
->body
->visit (this);
1480 o
->newline() << "#undef return";
1482 this->current_function
= 0;
1484 record_actions(0, true);
1486 if (this->probe_or_function_needs_deref_fault_handler
) {
1487 // Emit this handler only if the body included a
1488 // print/printf/etc. using a string or memory buffer!
1489 o
->newline() << "CATCH_DEREF_FAULT ();";
1492 o
->newline(-1) << "out:";
1493 o
->newline(1) << ";";
1495 // Function prologue: this is why we redirect the "return" above.
1496 // Decrement nesting level.
1497 o
->newline() << "c->nesting --;";
1499 o
->newline() << "#undef CONTEXT";
1500 o
->newline() << "#undef THIS";
1501 o
->newline(-1) << "}\n";
1505 #define DUPMETHOD_CALL 0
1506 #define DUPMETHOD_ALIAS 0
1507 #define DUPMETHOD_RENAME 1
1510 c_unparser::emit_probe (derived_probe
* v
)
1512 this->current_function
= 0;
1513 this->current_probe
= v
;
1514 this->tmpvar_counter
= 0;
1515 this->action_counter
= 0;
1517 // If we about to emit a probe that is exactly the same as another
1518 // probe previously emitted, make the second probe just call the
1521 // Notice we're using the probe body itself instead of the emitted C
1522 // probe body to compare probes. We need to do this because the
1523 // emitted C probe body has stuff in it like:
1524 // c->last_stmt = "identifier 'printf' at foo.stp:<line>:<column>";
1526 // which would make comparisons impossible.
1528 // --------------------------------------------------------------------------
1529 // NB: see also c_unparser:emit_common_header(), which deliberately but sadly
1530 // duplicates this calculation.
1531 // --------------------------------------------------------------------------
1535 // NB: statp is just for avoiding designation as duplicate. It need not be C.
1536 // NB: This code *could* be enclosed in an "if (session->timing)". That would
1537 // recognize more duplicate probe handlers, but then the generated code could
1538 // be very different with or without -t.
1539 oss
<< "c->statp = & time_" << v
->basest()->name
<< ";" << endl
;
1541 v
->print_dupe_stamp (oss
);
1542 v
->body
->print(oss
);
1544 // Since the generated C changes based on whether or not the probe
1545 // needs locks around global variables, this needs to be reflected
1546 // here. We don't want to treat as duplicate the handlers of
1547 // begin/end and normal probes that differ only in need_global_locks.
1548 oss
<< "# needs_global_locks: " << v
->needs_global_locks () << endl
;
1550 // If an identical probe has already been emitted, just call that
1552 if (probe_contents
.count(oss
.str()) != 0)
1554 string dupe
= probe_contents
[oss
.str()];
1556 // NB: Elision of context variable structs is a separate
1557 // operation which has already taken place by now.
1558 if (session
->verbose
> 1)
1559 clog
<< v
->name
<< " elided, duplicates " << dupe
<< endl
;
1562 // This one emits a direct call to the first copy.
1564 o
->newline() << "static void " << v
->name
<< " (struct context * __restrict__ c) ";
1565 o
->newline() << "{ " << dupe
<< " (c); }";
1566 #elif DUPMETHOD_ALIAS
1567 // This one defines a function alias, arranging gcc to emit
1568 // several equivalent symbols for the same function body.
1569 // For some reason, on gcc 4.1, this is twice as slow as
1572 o
->newline() << "static void " << v
->name
<< " (struct context * __restrict__ c) ";
1573 o
->line() << "__attribute__ ((alias (\"" << dupe
<< "\")));";
1574 #elif DUPMETHOD_RENAME
1575 // This one is sneaky. It emits nothing for duplicate probe
1576 // handlers. It instead redirects subsequent references to the
1577 // probe handler function to the first copy, *by name*.
1580 #error "Unknown duplicate elimination method"
1583 else // This probe is unique. Remember it and output it.
1585 this->probe_or_function_needs_deref_fault_handler
= false;
1588 o
->newline() << "#ifdef STP_TIMING";
1589 o
->newline() << "static __cacheline_aligned Stat " << "time_" << v
->basest()->name
<< ";";
1590 o
->newline() << "#endif";
1592 o
->newline() << "static void " << v
->name
<< " (struct context * __restrict__ c) ";
1596 probe_contents
[oss
.str()] = v
->name
;
1598 // initialize frame pointer
1599 o
->newline() << "struct " << v
->name
<< "_locals * __restrict__ l =";
1600 o
->newline(1) << "& c->locals[0]." << v
->name
<< ";";
1601 o
->newline(-1) << "(void) l;"; // make sure "l" is marked used
1603 o
->newline() << "#ifdef STP_TIMING";
1604 o
->newline() << "c->statp = & time_" << v
->basest()->name
<< ";";
1605 o
->newline() << "#endif";
1607 // emit probe local initialization block
1608 v
->emit_probe_local_init(o
);
1610 // emit all read/write locks for global variables
1611 varuse_collecting_visitor vut
;
1612 if (v
->needs_global_locks ())
1614 v
->body
->visit (& vut
);
1618 // initialize locals
1619 for (unsigned j
=0; j
<v
->locals
.size(); j
++)
1621 if (v
->locals
[j
]->index_types
.size() > 0) // array?
1622 throw semantic_error ("array locals not supported, missing global declaration?",
1624 else if (v
->locals
[j
]->type
== pe_long
)
1625 o
->newline() << "l->" << c_varname (v
->locals
[j
]->name
)
1627 else if (v
->locals
[j
]->type
== pe_string
)
1628 o
->newline() << "l->" << c_varname (v
->locals
[j
]->name
)
1631 throw semantic_error ("unsupported local variable type",
1635 v
->initialize_probe_context_vars (o
);
1637 v
->body
->visit (this);
1639 record_actions(0, true);
1641 if (this->probe_or_function_needs_deref_fault_handler
) {
1642 // Emit this handler only if the body included a
1643 // print/printf/etc. using a string or memory buffer!
1644 o
->newline() << "CATCH_DEREF_FAULT ();";
1647 o
->newline(-1) << "out:";
1648 // NB: no need to uninitialize locals, except if arrays/stats can
1651 // XXX: do this flush only if the body included a
1652 // print/printf/etc. routine!
1653 o
->newline(1) << "_stp_print_flush();";
1655 if (v
->needs_global_locks ())
1658 o
->newline(-1) << "}\n";
1662 this->current_probe
= 0;
1667 c_unparser::emit_locks(const varuse_collecting_visitor
& vut
)
1669 o
->newline() << "{";
1670 o
->newline(1) << "unsigned numtrylock = 0;";
1671 o
->newline() << "(void) numtrylock;";
1673 string last_locked_var
;
1674 for (unsigned i
= 0; i
< session
->globals
.size(); i
++)
1676 vardecl
* v
= session
->globals
[i
];
1677 bool read_p
= vut
.read
.find(v
) != vut
.read
.end();
1678 bool write_p
= vut
.written
.find(v
) != vut
.written
.end();
1679 if (!read_p
&& !write_p
) continue;
1681 if (v
->type
== pe_stats
) // read and write locks are flipped
1682 // Specifically, a "<<<" to a stats object is considered a
1683 // "shared-lock" operation, since it's implicitly done
1684 // per-cpu. But a "@op(x)" extraction is an "exclusive-lock"
1685 // one, as is a (sorted or unsorted) foreach, so those cases
1686 // are excluded by the w & !r condition below.
1688 if (write_p
&& !read_p
) { read_p
= true; write_p
= false; }
1689 else if (read_p
&& !write_p
) { read_p
= false; write_p
= true; }
1692 // We don't need to read lock "read-mostly" global variables. A
1693 // "read-mostly" global variable is only written to within
1694 // probes that don't need global variable locking (such as
1695 // begin/end probes). If vcv_needs_global_locks doesn't mark
1696 // the global as written to, then we don't have to lock it
1697 // here to read it safely.
1698 if (read_p
&& !write_p
)
1700 if (vcv_needs_global_locks
.written
.find(v
)
1701 == vcv_needs_global_locks
.written
.end())
1706 string (write_p
? "write" : "read") +
1707 "_trylock (& global.s_" + v
->name
+ "_lock)";
1709 o
->newline() << "while (! " << lockcall
1710 << "&& (++numtrylock < MAXTRYLOCK))";
1711 o
->newline(1) << "ndelay (TRYLOCKDELAY);";
1712 o
->newline(-1) << "if (unlikely (numtrylock >= MAXTRYLOCK)) {";
1713 o
->newline(1) << "atomic_inc (& skipped_count);";
1714 o
->newline() << "#ifdef STP_TIMING";
1715 o
->newline() << "atomic_inc (& global.s_" << c_varname (v
->name
) << "_lock_skip_count);";
1716 o
->newline() << "#endif";
1717 // The following works even if i==0. Note that using
1718 // globals[i-1]->name is wrong since that global may not have
1719 // been lockworthy by this probe.
1720 o
->newline() << "goto unlock_" << last_locked_var
<< ";";
1721 o
->newline(-1) << "}";
1723 last_locked_var
= v
->name
;
1726 o
->newline() << "if (0) goto unlock_;";
1728 o
->newline(-1) << "}";
1733 c_unparser::emit_unlocks(const varuse_collecting_visitor
& vut
)
1735 unsigned numvars
= 0;
1737 if (session
->verbose
>1)
1738 clog
<< current_probe
->name
<< " locks ";
1740 for (int i
= session
->globals
.size()-1; i
>=0; i
--) // in reverse order!
1742 vardecl
* v
= session
->globals
[i
];
1743 bool read_p
= vut
.read
.find(v
) != vut
.read
.end();
1744 bool write_p
= vut
.written
.find(v
) != vut
.written
.end();
1745 if (!read_p
&& !write_p
) continue;
1747 // Duplicate lock flipping logic from above
1748 if (v
->type
== pe_stats
)
1750 if (write_p
&& !read_p
) { read_p
= true; write_p
= false; }
1751 else if (read_p
&& !write_p
) { read_p
= false; write_p
= true; }
1754 // Duplicate "read-mostly" global variable logic from above.
1755 if (read_p
&& !write_p
)
1757 if (vcv_needs_global_locks
.written
.find(v
)
1758 == vcv_needs_global_locks
.written
.end())
1763 o
->newline(-1) << "unlock_" << v
->name
<< ":";
1766 if (session
->verbose
>1)
1767 clog
<< v
->name
<< "[" << (read_p
? "r" : "")
1768 << (write_p
? "w" : "") << "] ";
1770 if (write_p
) // emit write lock
1771 o
->newline() << "write_unlock (& global.s_" << v
->name
<< "_lock);";
1772 else // (read_p && !write_p) : emit read lock
1773 o
->newline() << "read_unlock (& global.s_" << v
->name
<< "_lock);";
1775 // fall through to next variable; thus the reverse ordering
1778 // emit plain "unlock" label, used if the very first lock failed.
1779 o
->newline(-1) << "unlock_: ;";
1782 if (numvars
) // is there a chance that any lock attempt failed?
1784 // Formerly, we checked skipped_count > MAXSKIPPED here, and set
1785 // SYSTEMTAP_SESSION_ERROR if so. But now, this check is shared
1786 // via common_probe_entryfn_epilogue().
1788 if (session
->verbose
>1)
1791 else if (session
->verbose
>1)
1792 clog
<< "nothing" << endl
;
1797 c_unparser::collect_map_index_types(vector
<vardecl
*> const & vars
,
1798 set
< pair
<vector
<exp_type
>, exp_type
> > & types
)
1800 for (unsigned i
= 0; i
< vars
.size(); ++i
)
1802 vardecl
*v
= vars
[i
];
1805 types
.insert(make_pair(v
->index_types
, v
->type
));
1811 mapvar::value_typename(exp_type e
)
1822 throw semantic_error("array type is neither string nor long");
1828 mapvar::key_typename(exp_type e
)
1837 throw semantic_error("array key is neither string nor long");
1843 mapvar::shortname(exp_type e
)
1852 throw semantic_error("array type is neither string nor long");
1859 c_unparser::emit_map_type_instantiations ()
1861 set
< pair
<vector
<exp_type
>, exp_type
> > types
;
1863 collect_map_index_types(session
->globals
, types
);
1865 for (unsigned i
= 0; i
< session
->probes
.size(); ++i
)
1866 collect_map_index_types(session
->probes
[i
]->locals
, types
);
1868 for (map
<string
,functiondecl
*>::iterator it
= session
->functions
.begin(); it
!= session
->functions
.end(); it
++)
1869 collect_map_index_types(it
->second
->locals
, types
);
1872 o
->newline() << "#include \"alloc.c\"";
1874 for (set
< pair
<vector
<exp_type
>, exp_type
> >::const_iterator i
= types
.begin();
1875 i
!= types
.end(); ++i
)
1877 o
->newline() << "#define VALUE_TYPE " << mapvar::value_typename(i
->second
);
1878 for (unsigned j
= 0; j
< i
->first
.size(); ++j
)
1880 string ktype
= mapvar::key_typename(i
->first
.at(j
));
1881 o
->newline() << "#define KEY" << (j
+1) << "_TYPE " << ktype
;
1883 if (i
->second
== pe_stats
)
1884 o
->newline() << "#include \"pmap-gen.c\"";
1886 o
->newline() << "#include \"map-gen.c\"";
1887 o
->newline() << "#undef VALUE_TYPE";
1888 for (unsigned j
= 0; j
< i
->first
.size(); ++j
)
1890 o
->newline() << "#undef KEY" << (j
+1) << "_TYPE";
1894 * For pmaps, we also need to include map-gen.c, because we might be accessing
1895 * the aggregated map. The better way to handle this is for pmap-gen.c to make
1896 * this include, but that's impossible with the way they are set up now.
1898 if (i
->second
== pe_stats
)
1900 o
->newline() << "#define VALUE_TYPE " << mapvar::value_typename(i
->second
);
1901 for (unsigned j
= 0; j
< i
->first
.size(); ++j
)
1903 string ktype
= mapvar::key_typename(i
->first
.at(j
));
1904 o
->newline() << "#define KEY" << (j
+1) << "_TYPE " << ktype
;
1906 o
->newline() << "#include \"map-gen.c\"";
1907 o
->newline() << "#undef VALUE_TYPE";
1908 for (unsigned j
= 0; j
< i
->first
.size(); ++j
)
1910 o
->newline() << "#undef KEY" << (j
+1) << "_TYPE";
1916 o
->newline() << "#include \"map.c\"";
1922 c_unparser::c_typename (exp_type e
)
1926 case pe_long
: return string("int64_t");
1927 case pe_string
: return string("string_t");
1928 case pe_stats
: return string("Stat");
1931 throw semantic_error ("cannot expand unknown type");
1937 c_unparser::c_varname (const string
& e
)
1939 // XXX: safeify, uniquefy, given name
1945 c_unparser::c_expression (expression
*e
)
1947 // We want to evaluate expression 'e' and return its value as a
1948 // string. In the case of expressions that are just numeric
1949 // constants, if we just print the value into a string, it won't
1950 // have the same value as being visited by c_unparser. For
1951 // instance, a numeric constant evaluated using print() would return
1952 // "5", while c_unparser::visit_literal_number() would
1953 // return "((int64_t)5LL)". String constants evaluated using
1954 // print() would just return the string, while
1955 // c_unparser::visit_literal_string() would return the string with
1956 // escaped double quote characters. So, we need to "visit" the
1959 // However, we have to be careful of side effects. Currently this
1960 // code is only being used for evaluating literal numbers and
1961 // strings, which currently have no side effects. Until needed
1962 // otherwise, limit the use of this function to literal numbers and
1964 if (e
->tok
->type
!= tok_number
&& e
->tok
->type
!= tok_string
)
1965 throw semantic_error("unsupported c_expression token type");
1967 // Create a fake output stream so we can grab the string output.
1969 translator_output
tmp_o(oss
);
1971 // Temporarily swap out the real translator_output stream with our
1973 translator_output
*saved_o
= o
;
1976 // Visit the expression then restore the original output stream
1985 c_unparser::c_assign (var
& lvalue
, const string
& rvalue
, const token
*tok
)
1987 switch (lvalue
.type())
1990 c_strcpy(lvalue
.value(), rvalue
);
1993 o
->newline() << lvalue
<< " = " << rvalue
<< ";";
1996 throw semantic_error ("unknown lvalue type in assignment", tok
);
2001 c_unparser::c_assign (const string
& lvalue
, expression
* rvalue
,
2004 if (rvalue
->type
== pe_long
)
2006 o
->newline() << lvalue
<< " = ";
2007 rvalue
->visit (this);
2010 else if (rvalue
->type
== pe_string
)
2012 c_strcpy (lvalue
, rvalue
);
2016 string fullmsg
= msg
+ " type unsupported";
2017 throw semantic_error (fullmsg
, rvalue
->tok
);
2023 c_unparser::c_assign (const string
& lvalue
, const string
& rvalue
,
2024 exp_type type
, const string
& msg
, const token
* tok
)
2026 if (type
== pe_long
)
2028 o
->newline() << lvalue
<< " = " << rvalue
<< ";";
2030 else if (type
== pe_string
)
2032 c_strcpy (lvalue
, rvalue
);
2036 string fullmsg
= msg
+ " type unsupported";
2037 throw semantic_error (fullmsg
, tok
);
2043 c_unparser_assignment::c_assignop(tmpvar
& res
,
2045 tmpvar
const & rval
,
2048 // This is common code used by scalar and array-element assignments.
2049 // It assumes an operator-and-assignment (defined by the 'pre' and
2050 // 'op' fields of c_unparser_assignment) is taking place between the
2051 // following set of variables:
2053 // res: the result of evaluating the expression, a temporary
2054 // lval: the lvalue of the expression, which may be damaged
2055 // rval: the rvalue of the expression, which is a temporary or constant
2057 // we'd like to work with a local tmpvar so we can overwrite it in
2058 // some optimized cases
2060 translator_output
* o
= parent
->o
;
2062 if (res
.type() == pe_string
)
2065 throw semantic_error ("post assignment on strings not supported",
2069 parent
->c_strcpy (lval
.value(), rval
.value());
2070 // no need for second copy
2073 else if (op
== ".=")
2075 parent
->c_strcat (lval
.value(), rval
.value());
2079 throw semantic_error ("string assignment operator " +
2080 op
+ " unsupported", tok
);
2082 else if (op
== "<<<")
2084 assert(lval
.type() == pe_stats
);
2085 assert(rval
.type() == pe_long
);
2086 assert(res
.type() == pe_long
);
2087 o
->newline() << res
<< " = " << rval
<< ";";
2088 o
->newline() << "_stp_stat_add (" << lval
<< ", " << res
<< ");";
2090 else if (res
.type() == pe_long
)
2092 // a lot of operators come through this "gate":
2093 // - vanilla assignment "="
2094 // - stats aggregation "<<<"
2095 // - modify-accumulate "+=" and many friends
2096 // - pre/post-crement "++"/"--"
2097 // - "/" and "%" operators, but these need special handling in kernel
2099 // compute the modify portion of a modify-accumulate
2101 unsigned oplen
= op
.size();
2103 macop
= "*error*"; // special shortcuts below
2104 else if (op
== "++" || op
== "+=")
2106 else if (op
== "--" || op
== "-=")
2108 else if (oplen
> 1 && op
[oplen
-1] == '=') // for *=, <<=, etc...
2112 throw semantic_error ("unknown macop for assignment", tok
);
2116 if (macop
== "/" || macop
== "%" || op
== "=")
2117 throw semantic_error ("invalid post-mode operator", tok
);
2119 o
->newline() << res
<< " = " << lval
<< ";";
2121 if (macop
== "+=" || macop
== "-=")
2122 o
->newline() << lval
<< " " << macop
<< " " << rval
<< ";";
2124 o
->newline() << lval
<< " = " << res
<< " " << macop
<< " " << rval
<< ";";
2128 if (op
== "=") // shortcut simple assignment
2130 o
->newline() << lval
<< " = " << rval
<< ";";
2135 if (macop
== "/=" || macop
== "%=")
2137 o
->newline() << "if (unlikely(!" << rval
<< ")) {";
2138 o
->newline(1) << "c->last_error = \"division by 0\";";
2139 o
->newline() << "goto out;";
2140 o
->newline(-1) << "}";
2141 o
->newline() << lval
<< " = "
2142 << ((macop
== "/=") ? "_stp_div64" : "_stp_mod64")
2143 << " (NULL, " << lval
<< ", " << rval
<< ");";
2146 o
->newline() << lval
<< " " << macop
<< " " << rval
<< ";";
2152 throw semantic_error ("assignment type not yet implemented", tok
);
2157 c_unparser::c_declare(exp_type ty
, const string
&name
)
2159 o
->newline() << c_typename (ty
) << " " << c_varname (name
) << ";";
2164 c_unparser::c_declare_static(exp_type ty
, const string
&name
)
2166 o
->newline() << "static " << c_typename (ty
) << " " << c_varname (name
) << ";";
2171 c_unparser::c_strcpy (const string
& lvalue
, const string
& rvalue
)
2173 o
->newline() << "strlcpy ("
2175 << rvalue
<< ", MAXSTRINGLEN);";
2180 c_unparser::c_strcpy (const string
& lvalue
, expression
* rvalue
)
2182 o
->newline() << "strlcpy (" << lvalue
<< ", ";
2183 rvalue
->visit (this);
2184 o
->line() << ", MAXSTRINGLEN);";
2189 c_unparser::c_strcat (const string
& lvalue
, const string
& rvalue
)
2191 o
->newline() << "strlcat ("
2193 << rvalue
<< ", MAXSTRINGLEN);";
2198 c_unparser::c_strcat (const string
& lvalue
, expression
* rvalue
)
2200 o
->newline() << "strlcat (" << lvalue
<< ", ";
2201 rvalue
->visit (this);
2202 o
->line() << ", MAXSTRINGLEN);";
2207 c_unparser::is_local(vardecl
const *r
, token
const *tok
)
2211 for (unsigned i
=0; i
<current_probe
->locals
.size(); i
++)
2213 if (current_probe
->locals
[i
] == r
)
2217 else if (current_function
)
2219 for (unsigned i
=0; i
<current_function
->locals
.size(); i
++)
2221 if (current_function
->locals
[i
] == r
)
2225 for (unsigned i
=0; i
<current_function
->formal_args
.size(); i
++)
2227 if (current_function
->formal_args
[i
] == r
)
2232 for (unsigned i
=0; i
<session
->globals
.size(); i
++)
2234 if (session
->globals
[i
] == r
)
2239 throw semantic_error ("unresolved symbol", tok
);
2241 throw semantic_error ("unresolved symbol: " + r
->name
);
2246 c_unparser::gensym(exp_type ty
)
2248 return tmpvar (ty
, tmpvar_counter
);
2252 c_unparser::gensym_aggregate()
2254 return aggvar (tmpvar_counter
);
2259 c_unparser::getvar(vardecl
*v
, token
const *tok
)
2261 bool loc
= is_local (v
, tok
);
2263 return var (loc
, v
->type
, v
->name
);
2267 std::map
<std::string
, statistic_decl
>::const_iterator i
;
2268 i
= session
->stat_decls
.find(v
->name
);
2269 if (i
!= session
->stat_decls
.end())
2271 return var (loc
, v
->type
, sd
, v
->name
);
2277 c_unparser::getmap(vardecl
*v
, token
const *tok
)
2280 throw semantic_error("attempt to use scalar where map expected", tok
);
2282 std::map
<std::string
, statistic_decl
>::const_iterator i
;
2283 i
= session
->stat_decls
.find(v
->name
);
2284 if (i
!= session
->stat_decls
.end())
2286 return mapvar (is_local (v
, tok
), v
->type
, sd
,
2287 v
->name
, v
->index_types
, v
->maxsize
);
2292 c_unparser::getiter(symbol
*s
)
2294 return itervar (s
, tmpvar_counter
);
2298 // Queue up some actions to remove from actionremaining. Set update=true at
2299 // the end of basic blocks to actually update actionremaining and check it
2300 // against MAXACTION.
2302 c_unparser::record_actions (unsigned actions
, bool update
)
2304 action_counter
+= actions
;
2306 // Update if needed, or after queueing up a few actions, in case of very
2307 // large code sequences.
2308 if ((update
&& action_counter
> 0) || action_counter
>= 10/*<-arbitrary*/)
2310 o
->newline() << "c->actionremaining -= " << action_counter
<< ";";
2311 o
->newline() << "if (unlikely (c->actionremaining <= 0)) {";
2312 o
->newline(1) << "c->last_error = \"MAXACTION exceeded\";";
2313 o
->newline() << "goto out;";
2314 o
->newline(-1) << "}";
2321 c_unparser::visit_block (block
*s
)
2323 o
->newline() << "{";
2326 for (unsigned i
=0; i
<s
->statements
.size(); i
++)
2330 s
->statements
[i
]->visit (this);
2333 catch (const semantic_error
& e
)
2335 session
->print_error (e
);
2338 o
->newline(-1) << "}";
2343 c_unparser::visit_embeddedcode (embeddedcode
*s
)
2345 o
->newline() << "{";
2346 o
->newline(1) << s
->code
;
2347 o
->newline(-1) << "}";
2352 c_unparser::visit_null_statement (null_statement
*)
2354 o
->newline() << "/* null */;";
2359 c_unparser::visit_expr_statement (expr_statement
*s
)
2361 o
->newline() << "(void) ";
2362 s
->value
->visit (this);
2369 c_unparser::visit_if_statement (if_statement
*s
)
2371 record_actions(1, true);
2372 o
->newline() << "if (";
2374 s
->condition
->visit (this);
2378 s
->thenblock
->visit (this);
2379 record_actions(0, true);
2380 o
->newline(-1) << "}";
2383 o
->newline() << "else {";
2385 s
->elseblock
->visit (this);
2386 record_actions(0, true);
2387 o
->newline(-1) << "}";
2393 c_tmpcounter::visit_block (block
*s
)
2395 // Key insight: individual statements of a block can reuse
2396 // temporary variable slots, since temporaries don't survive
2397 // statement boundaries. So we use gcc's anonymous union/struct
2398 // facility to explicitly overlay the temporaries.
2399 parent
->o
->newline() << "union {";
2400 parent
->o
->indent(1);
2401 for (unsigned i
=0; i
<s
->statements
.size(); i
++)
2403 // To avoid lots of empty structs inside the union, remember
2404 // where we are now. Then, output the struct start and remember
2405 // that positon. If when we get done with the statement we
2406 // haven't moved, then we don't really need the struct. To get
2407 // rid of the struct start we output, we'll seek back to where
2408 // we were before we output the struct.
2409 std::ostream::pos_type before_struct_pos
= parent
->o
->tellp();
2410 parent
->o
->newline() << "struct {";
2411 parent
->o
->indent(1);
2412 std::ostream::pos_type after_struct_pos
= parent
->o
->tellp();
2413 s
->statements
[i
]->visit (this);
2414 parent
->o
->indent(-1);
2415 if (after_struct_pos
== parent
->o
->tellp())
2416 parent
->o
->seekp(before_struct_pos
);
2418 parent
->o
->newline() << "};";
2420 parent
->o
->newline(-1) << "};";
2424 c_tmpcounter::visit_for_loop (for_loop
*s
)
2426 if (s
->init
) s
->init
->visit (this);
2427 s
->cond
->visit (this);
2428 s
->block
->visit (this);
2429 if (s
->incr
) s
->incr
->visit (this);
2434 c_unparser::visit_for_loop (for_loop
*s
)
2436 string ctr
= stringify (label_counter
++);
2437 string toplabel
= "top_" + ctr
;
2438 string contlabel
= "continue_" + ctr
;
2439 string breaklabel
= "break_" + ctr
;
2442 if (s
->init
) s
->init
->visit (this);
2443 record_actions(1, true);
2446 o
->newline(-1) << toplabel
<< ":";
2448 // Emit an explicit action here to cover the act of iteration.
2449 // Equivalently, it can stand for the evaluation of the condition
2454 o
->newline() << "if (! (";
2455 if (s
->cond
->type
!= pe_long
)
2456 throw semantic_error ("expected numeric type", s
->cond
->tok
);
2457 s
->cond
->visit (this);
2458 o
->line() << ")) goto " << breaklabel
<< ";";
2461 loop_break_labels
.push_back (breaklabel
);
2462 loop_continue_labels
.push_back (contlabel
);
2463 s
->block
->visit (this);
2464 record_actions(0, true);
2465 loop_break_labels
.pop_back ();
2466 loop_continue_labels
.pop_back ();
2469 o
->newline(-1) << contlabel
<< ":";
2471 if (s
->incr
) s
->incr
->visit (this);
2472 o
->newline() << "goto " << toplabel
<< ";";
2475 o
->newline(-1) << breaklabel
<< ":";
2476 o
->newline(1) << "; /* dummy statement */";
2480 struct arrayindex_downcaster
2481 : public traversing_visitor
2485 arrayindex_downcaster (arrayindex
*& arr
)
2489 void visit_arrayindex (arrayindex
* e
)
2497 expression_is_arrayindex (expression
*e
,
2500 arrayindex
*h
= NULL
;
2501 arrayindex_downcaster
d(h
);
2503 if (static_cast<void*>(h
) == static_cast<void*>(e
))
2513 c_tmpcounter::visit_foreach_loop (foreach_loop
*s
)
2517 classify_indexable (s
->base
, array
, hist
);
2521 itervar iv
= parent
->getiter (array
);
2522 parent
->o
->newline() << iv
.declare();
2526 // See commentary in c_tmpcounter::visit_arrayindex for
2527 // discussion of tmpvars required to look into @hist_op(...)
2530 // First make sure we have exactly one pe_long variable to use as
2531 // our bucket index.
2533 if (s
->indexes
.size() != 1 || s
->indexes
[0]->referent
->type
!= pe_long
)
2534 throw semantic_error("Invalid indexing of histogram", s
->tok
);
2536 // Then declare what we need to form the aggregate we're
2537 // iterating over, and all the tmpvars needed by our call to
2538 // load_aggregate().
2540 aggvar agg
= parent
->gensym_aggregate ();
2541 agg
.declare(*(this->parent
));
2543 symbol
*sym
= get_symbol_within_expression (hist
->stat
);
2544 var v
= parent
->getvar(sym
->referent
, sym
->tok
);
2545 if (sym
->referent
->arity
!= 0)
2547 arrayindex
*arr
= NULL
;
2548 if (!expression_is_arrayindex (hist
->stat
, arr
))
2549 throw semantic_error("expected arrayindex expression in iterated hist_op", s
->tok
);
2551 for (unsigned i
=0; i
<sym
->referent
->index_types
.size(); i
++)
2553 tmpvar ix
= parent
->gensym (sym
->referent
->index_types
[i
]);
2554 ix
.declare (*parent
);
2555 arr
->indexes
[i
]->visit(this);
2560 // Create a temporary for the loop limit counter and the limit
2561 // expression result.
2564 tmpvar res_limit
= parent
->gensym (pe_long
);
2565 res_limit
.declare(*parent
);
2567 s
->limit
->visit (this);
2569 tmpvar limitv
= parent
->gensym (pe_long
);
2570 limitv
.declare(*parent
);
2573 s
->block
->visit (this);
2577 c_unparser::visit_foreach_loop (foreach_loop
*s
)
2581 classify_indexable (s
->base
, array
, hist
);
2585 mapvar mv
= getmap (array
->referent
, s
->tok
);
2586 itervar iv
= getiter (array
);
2589 string ctr
= stringify (label_counter
++);
2590 string toplabel
= "top_" + ctr
;
2591 string contlabel
= "continue_" + ctr
;
2592 string breaklabel
= "break_" + ctr
;
2594 // NB: structure parallels for_loop
2598 tmpvar
*res_limit
= NULL
;
2601 // Evaluate the limit expression once.
2602 res_limit
= new tmpvar(gensym(pe_long
));
2603 c_assign (res_limit
->value(), s
->limit
, "foreach limit");
2606 // aggregate array if required
2607 if (mv
.is_parallel())
2609 o
->newline() << "if (unlikely(NULL == " << mv
.calculate_aggregate() << ")) {";
2610 o
->newline(1) << "c->last_error = \"aggregation overflow in " << mv
<< "\";";
2611 o
->newline() << "goto out;";
2612 o
->newline(-1) << "}";
2614 // sort array if desired
2615 if (s
->sort_direction
)
2619 // If the user wanted us to sort by value, we'll sort by
2620 // @count instead for aggregates. '-5' tells the
2621 // runtime to sort by count.
2622 if (s
->sort_column
== 0)
2625 sort_column
= s
->sort_column
;
2627 o
->newline() << "else"; // only sort if aggregation was ok
2630 o
->newline(1) << "_stp_map_sortn ("
2631 << mv
.fetch_existing_aggregate() << ", "
2632 << *res_limit
<< ", " << sort_column
<< ", "
2633 << - s
->sort_direction
<< ");";
2637 o
->newline(1) << "_stp_map_sort ("
2638 << mv
.fetch_existing_aggregate() << ", "
2639 << sort_column
<< ", "
2640 << - s
->sort_direction
<< ");";
2647 // sort array if desired
2648 if (s
->sort_direction
)
2652 o
->newline() << "_stp_map_sortn (" << mv
.value() << ", "
2653 << *res_limit
<< ", " << s
->sort_column
<< ", "
2654 << - s
->sort_direction
<< ");";
2658 o
->newline() << "_stp_map_sort (" << mv
.value() << ", "
2659 << s
->sort_column
<< ", "
2660 << - s
->sort_direction
<< ");";
2665 // NB: sort direction sense is opposite in runtime, thus the negation
2667 if (mv
.is_parallel())
2668 aggregations_active
.insert(mv
.value());
2669 o
->newline() << iv
<< " = " << iv
.start (mv
) << ";";
2671 tmpvar
*limitv
= NULL
;
2674 // Create the loop limit variable here and initialize it.
2675 limitv
= new tmpvar(gensym (pe_long
));
2676 o
->newline() << *limitv
<< " = 0LL;";
2679 record_actions(1, true);
2682 o
->newline(-1) << toplabel
<< ":";
2684 // Emit an explicit action here to cover the act of iteration.
2685 // Equivalently, it can stand for the evaluation of the
2686 // condition expression.
2690 o
->newline() << "if (! (" << iv
<< ")) goto " << breaklabel
<< ";";
2693 loop_break_labels
.push_back (breaklabel
);
2694 loop_continue_labels
.push_back (contlabel
);
2695 o
->newline() << "{";
2700 // If we've been through LIMIT loop iterations, quit.
2701 o
->newline() << "if (" << *limitv
<< "++ >= " << *res_limit
2702 << ") goto " << breaklabel
<< ";";
2704 // We're done with limitv and res_limit.
2709 for (unsigned i
= 0; i
< s
->indexes
.size(); ++i
)
2711 // copy the iter values into the specified locals
2712 var v
= getvar (s
->indexes
[i
]->referent
);
2713 c_assign (v
, iv
.get_key (v
.type(), i
), s
->tok
);
2715 s
->block
->visit (this);
2716 record_actions(0, true);
2717 o
->newline(-1) << "}";
2718 loop_break_labels
.pop_back ();
2719 loop_continue_labels
.pop_back ();
2722 o
->newline(-1) << contlabel
<< ":";
2723 o
->newline(1) << iv
<< " = " << iv
.next (mv
) << ";";
2724 o
->newline() << "goto " << toplabel
<< ";";
2727 o
->newline(-1) << breaklabel
<< ":";
2728 o
->newline(1) << "; /* dummy statement */";
2730 if (mv
.is_parallel())
2731 aggregations_active
.erase(mv
.value());
2735 // Iterating over buckets in a histogram.
2736 assert(s
->indexes
.size() == 1);
2737 assert(s
->indexes
[0]->referent
->type
== pe_long
);
2738 var bucketvar
= getvar (s
->indexes
[0]->referent
);
2740 aggvar agg
= gensym_aggregate ();
2741 load_aggregate(hist
->stat
, agg
);
2743 symbol
*sym
= get_symbol_within_expression (hist
->stat
);
2744 var v
= getvar(sym
->referent
, sym
->tok
);
2745 v
.assert_hist_compatible(*hist
);
2747 tmpvar
*res_limit
= NULL
;
2748 tmpvar
*limitv
= NULL
;
2751 // Evaluate the limit expression once.
2752 res_limit
= new tmpvar(gensym(pe_long
));
2753 c_assign (res_limit
->value(), s
->limit
, "foreach limit");
2755 // Create the loop limit variable here and initialize it.
2756 limitv
= new tmpvar(gensym (pe_long
));
2757 o
->newline() << *limitv
<< " = 0LL;";
2760 // XXX: break / continue don't work here yet
2761 record_actions(1, true);
2762 o
->newline() << "for (" << bucketvar
<< " = 0; "
2763 << bucketvar
<< " < " << v
.buckets() << "; "
2764 << bucketvar
<< "++) { ";
2769 // If we've been through LIMIT loop iterations, quit.
2770 o
->newline() << "if (" << *limitv
<< "++ >= " << *res_limit
2773 // We're done with limitv and res_limit.
2778 s
->block
->visit (this);
2779 record_actions(1, true);
2780 o
->newline(-1) << "}";
2786 c_unparser::visit_return_statement (return_statement
* s
)
2788 if (current_function
== 0)
2789 throw semantic_error ("cannot 'return' from probe", s
->tok
);
2791 if (s
->value
->type
!= current_function
->type
)
2792 throw semantic_error ("return type mismatch", current_function
->tok
,
2795 c_assign ("l->__retvalue", s
->value
, "return value");
2796 record_actions(1, true);
2797 o
->newline() << "goto out;";
2802 c_unparser::visit_next_statement (next_statement
* s
)
2804 if (current_probe
== 0)
2805 throw semantic_error ("cannot 'next' from function", s
->tok
);
2807 record_actions(1, true);
2808 o
->newline() << "goto out;";
2812 struct delete_statement_operand_tmp_visitor
:
2813 public traversing_visitor
2815 c_tmpcounter
*parent
;
2816 delete_statement_operand_tmp_visitor (c_tmpcounter
*p
):
2819 //void visit_symbol (symbol* e);
2820 void visit_arrayindex (arrayindex
* e
);
2824 struct delete_statement_operand_visitor
:
2825 public throwing_visitor
2828 delete_statement_operand_visitor (c_unparser
*p
):
2829 throwing_visitor ("invalid operand of delete expression"),
2832 void visit_symbol (symbol
* e
);
2833 void visit_arrayindex (arrayindex
* e
);
2837 delete_statement_operand_visitor::visit_symbol (symbol
* e
)
2839 assert (e
->referent
!= 0);
2840 if (e
->referent
->arity
> 0)
2842 mapvar mvar
= parent
->getmap(e
->referent
, e
->tok
);
2843 /* NB: Memory deallocation/allocation operations
2844 are not generally safe.
2845 parent->o->newline() << mvar.fini ();
2846 parent->o->newline() << mvar.init ();
2848 if (mvar
.is_parallel())
2849 parent
->o
->newline() << "_stp_pmap_clear (" << mvar
.value() << ");";
2851 parent
->o
->newline() << "_stp_map_clear (" << mvar
.value() << ");";
2855 var v
= parent
->getvar(e
->referent
, e
->tok
);
2859 parent
->o
->newline() << "_stp_stat_clear (" << v
.value() << ");";
2862 parent
->o
->newline() << v
.value() << " = 0;";
2865 parent
->o
->newline() << v
.value() << "[0] = '\\0';";
2869 throw semantic_error("Cannot delete unknown expression type", e
->tok
);
2875 delete_statement_operand_tmp_visitor::visit_arrayindex (arrayindex
* e
)
2879 classify_indexable (e
->base
, array
, hist
);
2883 assert (array
->referent
!= 0);
2884 vardecl
* r
= array
->referent
;
2886 // One temporary per index dimension.
2887 for (unsigned i
=0; i
<r
->index_types
.size(); i
++)
2889 tmpvar ix
= parent
->parent
->gensym (r
->index_types
[i
]);
2890 ix
.declare (*(parent
->parent
));
2891 e
->indexes
[i
]->visit(parent
);
2896 throw semantic_error("cannot delete histogram bucket entries\n", e
->tok
);
2901 delete_statement_operand_visitor::visit_arrayindex (arrayindex
* e
)
2905 classify_indexable (e
->base
, array
, hist
);
2910 parent
->load_map_indices (e
, idx
);
2913 mapvar mvar
= parent
->getmap (array
->referent
, e
->tok
);
2914 parent
->o
->newline() << mvar
.del (idx
) << ";";
2919 throw semantic_error("cannot delete histogram bucket entries\n", e
->tok
);
2925 c_tmpcounter::visit_delete_statement (delete_statement
* s
)
2927 delete_statement_operand_tmp_visitor
dv (this);
2928 s
->value
->visit (&dv
);
2933 c_unparser::visit_delete_statement (delete_statement
* s
)
2935 delete_statement_operand_visitor
dv (this);
2936 s
->value
->visit (&dv
);
2942 c_unparser::visit_break_statement (break_statement
* s
)
2944 if (loop_break_labels
.size() == 0)
2945 throw semantic_error ("cannot 'break' outside loop", s
->tok
);
2947 record_actions(1, true);
2948 string label
= loop_break_labels
[loop_break_labels
.size()-1];
2949 o
->newline() << "goto " << label
<< ";";
2954 c_unparser::visit_continue_statement (continue_statement
* s
)
2956 if (loop_continue_labels
.size() == 0)
2957 throw semantic_error ("cannot 'continue' outside loop", s
->tok
);
2959 record_actions(1, true);
2960 string label
= loop_continue_labels
[loop_continue_labels
.size()-1];
2961 o
->newline() << "goto " << label
<< ";";
2967 c_unparser::visit_literal_string (literal_string
* e
)
2969 const string
& v
= e
->value
;
2971 for (unsigned i
=0; i
<v
.size(); i
++)
2972 // NB: The backslash character is specifically passed through as is.
2973 // This is because our parser treats "\" as an ordinary character, not
2974 // an escape sequence, leaving it to the C compiler (and this function)
2975 // to treat it as such. If we were to escape it, there would be no way
2976 // of generating C-level escapes from script code.
2977 // See also print_format::components_to_string and lex_cast_qstring
2978 if (v
[i
] == '"') // or other escapeworthy characters?
2979 o
->line() << '\\' << '"';
2987 c_unparser::visit_literal_number (literal_number
* e
)
2989 // This looks ugly, but tries to be warning-free on 32- and 64-bit
2991 // NB: this needs to be signed!
2992 if (e
->value
== -9223372036854775807LL-1) // PR 5023
2993 o
->line() << "((int64_t)" << (unsigned long long) e
->value
<< "ULL)";
2995 o
->line() << "((int64_t)" << e
->value
<< "LL)";
3000 c_tmpcounter::visit_binary_expression (binary_expression
* e
)
3002 if (e
->op
== "/" || e
->op
== "%")
3004 tmpvar left
= parent
->gensym (pe_long
);
3005 tmpvar right
= parent
->gensym (pe_long
);
3006 if (e
->left
->tok
->type
!= tok_number
)
3007 left
.declare (*parent
);
3008 if (e
->right
->tok
->type
!= tok_number
)
3009 right
.declare (*parent
);
3012 e
->left
->visit (this);
3013 e
->right
->visit (this);
3018 c_unparser::visit_binary_expression (binary_expression
* e
)
3020 if (e
->type
!= pe_long
||
3021 e
->left
->type
!= pe_long
||
3022 e
->right
->type
!= pe_long
)
3023 throw semantic_error ("expected numeric types", e
->tok
);
3033 e
->left
->visit (this);
3034 o
->line() << ") " << e
->op
<< " (";
3035 e
->right
->visit (this);
3038 else if (e
->op
== ">>" ||
3042 e
->left
->visit (this);
3043 o
->line() << ") " << e
->op
<< "max(min(";
3044 e
->right
->visit (this);
3045 o
->line() << ", (int64_t)64LL), (int64_t)0LL))"; // between 0 and 64
3047 else if (e
->op
== "/" ||
3050 // % and / need a division-by-zero check; and thus two temporaries
3051 // for proper evaluation order
3052 tmpvar left
= gensym (pe_long
);
3053 tmpvar right
= gensym (pe_long
);
3058 if (e
->left
->tok
->type
== tok_number
)
3059 left
.override(c_expression(e
->left
));
3062 o
->newline() << left
<< " = ";
3063 e
->left
->visit (this);
3067 if (e
->right
->tok
->type
== tok_number
)
3068 right
.override(c_expression(e
->right
));
3071 o
->newline() << right
<< " = ";
3072 e
->right
->visit (this);
3076 o
->newline() << "if (unlikely(!" << right
<< ")) {";
3077 o
->newline(1) << "c->last_error = \"division by 0\";";
3078 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
3079 o
->newline() << "goto out;";
3080 o
->newline(-1) << "}";
3081 o
->newline() << ((e
->op
== "/") ? "_stp_div64" : "_stp_mod64")
3082 << " (NULL, " << left
<< ", " << right
<< ");";
3084 o
->newline(-1) << "})";
3087 throw semantic_error ("operator not yet implemented", e
->tok
);
3092 c_unparser::visit_unary_expression (unary_expression
* e
)
3094 if (e
->type
!= pe_long
||
3095 e
->operand
->type
!= pe_long
)
3096 throw semantic_error ("expected numeric types", e
->tok
);
3100 // NB: Subtraction is special, since negative literals in the
3101 // script language show up as unary negations over positive
3102 // literals here. This makes it "exciting" for emitting pure
3103 // C since: - 0x8000_0000_0000_0000 ==> - (- 9223372036854775808)
3104 // This would constitute a signed overflow, which gcc warns on
3105 // unless -ftrapv/-J are in CFLAGS - which they're not.
3107 o
->line() << "(int64_t)(0 " << e
->op
<< " (uint64_t)(";
3108 e
->operand
->visit (this);
3113 o
->line() << "(" << e
->op
<< " (";
3114 e
->operand
->visit (this);
3120 c_unparser::visit_logical_or_expr (logical_or_expr
* e
)
3122 if (e
->type
!= pe_long
||
3123 e
->left
->type
!= pe_long
||
3124 e
->right
->type
!= pe_long
)
3125 throw semantic_error ("expected numeric types", e
->tok
);
3128 e
->left
->visit (this);
3129 o
->line() << ") " << e
->op
<< " (";
3130 e
->right
->visit (this);
3136 c_unparser::visit_logical_and_expr (logical_and_expr
* e
)
3138 if (e
->type
!= pe_long
||
3139 e
->left
->type
!= pe_long
||
3140 e
->right
->type
!= pe_long
)
3141 throw semantic_error ("expected numeric types", e
->tok
);
3144 e
->left
->visit (this);
3145 o
->line() << ") " << e
->op
<< " (";
3146 e
->right
->visit (this);
3152 c_tmpcounter::visit_array_in (array_in
* e
)
3156 classify_indexable (e
->operand
->base
, array
, hist
);
3160 assert (array
->referent
!= 0);
3161 vardecl
* r
= array
->referent
;
3163 // One temporary per index dimension.
3164 for (unsigned i
=0; i
<r
->index_types
.size(); i
++)
3166 tmpvar ix
= parent
->gensym (r
->index_types
[i
]);
3167 ix
.declare (*parent
);
3168 e
->operand
->indexes
[i
]->visit(this);
3171 // A boolean result.
3172 tmpvar res
= parent
->gensym (e
->type
);
3173 res
.declare (*parent
);
3179 // 'foo in @hist_op(...)' is true iff
3180 // '@hist_op(...)[foo]' is nonzero
3182 // so we just delegate to the latter call, since int64_t is also
3183 // our boolean type.
3184 e
->operand
->visit(this);
3190 c_unparser::visit_array_in (array_in
* e
)
3194 classify_indexable (e
->operand
->base
, array
, hist
);
3198 stmt_expr
block(*this);
3201 load_map_indices (e
->operand
, idx
);
3202 // o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
3204 tmpvar res
= gensym (pe_long
);
3205 mapvar mvar
= getmap (array
->referent
, e
->tok
);
3206 c_assign (res
, mvar
.exists(idx
), e
->tok
);
3208 o
->newline() << res
<< ";";
3214 // 'foo in @hist_op(...)' is true iff
3215 // '@hist_op(...)[foo]' is nonzero
3217 // so we just delegate to the latter call, since int64_t is also
3218 // our boolean type.
3219 e
->operand
->visit(this);
3225 c_unparser::visit_comparison (comparison
* e
)
3229 if (e
->left
->type
== pe_string
)
3231 if (e
->right
->type
!= pe_string
)
3232 throw semantic_error ("expected string types", e
->tok
);
3234 o
->line() << "strncmp (";
3235 e
->left
->visit (this);
3237 e
->right
->visit (this);
3238 o
->line() << ", MAXSTRINGLEN";
3239 o
->line() << ") " << e
->op
<< " 0";
3241 else if (e
->left
->type
== pe_long
)
3243 if (e
->right
->type
!= pe_long
)
3244 throw semantic_error ("expected numeric types", e
->tok
);
3247 e
->left
->visit (this);
3248 o
->line() << ") " << e
->op
<< " (";
3249 e
->right
->visit (this);
3253 throw semantic_error ("unexpected type", e
->left
->tok
);
3260 c_tmpcounter::visit_concatenation (concatenation
* e
)
3262 tmpvar t
= parent
->gensym (e
->type
);
3263 t
.declare (*parent
);
3264 e
->left
->visit (this);
3265 e
->right
->visit (this);
3270 c_unparser::visit_concatenation (concatenation
* e
)
3273 throw semantic_error ("unexpected concatenation operator", e
->tok
);
3275 if (e
->type
!= pe_string
||
3276 e
->left
->type
!= pe_string
||
3277 e
->right
->type
!= pe_string
)
3278 throw semantic_error ("expected string types", e
->tok
);
3280 tmpvar t
= gensym (e
->type
);
3284 // o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
3285 c_assign (t
.value(), e
->left
, "assignment");
3286 c_strcat (t
.value(), e
->right
);
3287 o
->newline() << t
<< ";";
3288 o
->newline(-1) << "})";
3293 c_unparser::visit_ternary_expression (ternary_expression
* e
)
3295 if (e
->cond
->type
!= pe_long
)
3296 throw semantic_error ("expected numeric condition", e
->cond
->tok
);
3298 if (e
->truevalue
->type
!= e
->falsevalue
->type
||
3299 e
->type
!= e
->truevalue
->type
||
3300 (e
->truevalue
->type
!= pe_long
&& e
->truevalue
->type
!= pe_string
))
3301 throw semantic_error ("expected matching types", e
->tok
);
3304 e
->cond
->visit (this);
3305 o
->line() << ") ? (";
3306 e
->truevalue
->visit (this);
3307 o
->line() << ") : (";
3308 e
->falsevalue
->visit (this);
3314 c_tmpcounter::visit_assignment (assignment
*e
)
3316 c_tmpcounter_assignment
tav (this, e
->op
, e
->right
);
3317 e
->left
->visit (& tav
);
3322 c_unparser::visit_assignment (assignment
* e
)
3326 if (e
->type
!= pe_long
)
3327 throw semantic_error ("non-number <<< expression", e
->tok
);
3329 if (e
->left
->type
!= pe_stats
)
3330 throw semantic_error ("non-stats left operand to <<< expression", e
->left
->tok
);
3332 if (e
->right
->type
!= pe_long
)
3333 throw semantic_error ("non-number right operand to <<< expression", e
->right
->tok
);
3338 if (e
->type
!= e
->left
->type
)
3339 throw semantic_error ("type mismatch", e
->tok
,
3340 "vs", e
->left
->tok
);
3341 if (e
->right
->type
!= e
->left
->type
)
3342 throw semantic_error ("type mismatch", e
->right
->tok
,
3343 "vs", e
->left
->tok
);
3346 c_unparser_assignment
tav (this, e
->op
, e
->right
);
3347 e
->left
->visit (& tav
);
3352 c_tmpcounter::visit_pre_crement (pre_crement
* e
)
3354 c_tmpcounter_assignment
tav (this, e
->op
, 0);
3355 e
->operand
->visit (& tav
);
3360 c_unparser::visit_pre_crement (pre_crement
* e
)
3362 if (e
->type
!= pe_long
||
3363 e
->type
!= e
->operand
->type
)
3364 throw semantic_error ("expected numeric type", e
->tok
);
3366 c_unparser_assignment
tav (this, e
->op
, false);
3367 e
->operand
->visit (& tav
);
3372 c_tmpcounter::visit_post_crement (post_crement
* e
)
3374 c_tmpcounter_assignment
tav (this, e
->op
, 0, true);
3375 e
->operand
->visit (& tav
);
3380 c_unparser::visit_post_crement (post_crement
* e
)
3382 if (e
->type
!= pe_long
||
3383 e
->type
!= e
->operand
->type
)
3384 throw semantic_error ("expected numeric type", e
->tok
);
3386 c_unparser_assignment
tav (this, e
->op
, true);
3387 e
->operand
->visit (& tav
);
3392 c_unparser::visit_symbol (symbol
* e
)
3394 assert (e
->referent
!= 0);
3395 vardecl
* r
= e
->referent
;
3397 if (r
->index_types
.size() != 0)
3398 throw semantic_error ("invalid reference to array", e
->tok
);
3400 var v
= getvar(r
, e
->tok
);
3406 c_tmpcounter_assignment::prepare_rvalue (tmpvar
& rval
)
3410 // literal number and strings don't need any temporaries declared
3411 if (rvalue
->tok
->type
!= tok_number
&& rvalue
->tok
->type
!= tok_string
)
3412 rval
.declare (*(parent
->parent
));
3414 rvalue
->visit (parent
);
3419 c_tmpcounter_assignment::c_assignop(tmpvar
& res
)
3421 if (res
.type() == pe_string
)
3423 // string assignment doesn't need any temporaries declared
3425 else if (op
== "<<<")
3426 res
.declare (*(parent
->parent
));
3427 else if (res
.type() == pe_long
)
3429 // Only the 'post' operators ('x++') need a temporary declared.
3431 res
.declare (*(parent
->parent
));
3435 // Assignment expansion is tricky.
3437 // Because assignments are nestable expressions, we have
3438 // to emit C constructs that are nestable expressions too.
3439 // We have to evaluate the given expressions the proper number of times,
3440 // including array indices.
3441 // We have to lock the lvalue (if global) against concurrent modification,
3442 // especially with modify-assignment operations (+=, ++).
3443 // We have to check the rvalue (for division-by-zero checks).
3445 // In the normal "pre=false" case, for (A op B) emit:
3446 // ({ tmp = B; check(B); lock(A); res = A op tmp; A = res; unlock(A); res; })
3447 // In the "pre=true" case, emit instead:
3448 // ({ tmp = B; check(B); lock(A); res = A; A = res op tmp; unlock(A); res; })
3450 // (op is the plain operator portion of a combined calculate/assignment:
3451 // "+" for "+=", and so on. It is in the "macop" variable below.)
3453 // For array assignments, additional temporaries are used for each
3454 // index, which are expanded before the "tmp=B" expression, in order
3455 // to consistently order evaluation of lhs before rhs.
3459 c_tmpcounter_assignment::visit_symbol (symbol
*e
)
3461 exp_type ty
= rvalue
? rvalue
->type
: e
->type
;
3462 tmpvar rval
= parent
->parent
->gensym (ty
);
3463 tmpvar res
= parent
->parent
->gensym (ty
);
3465 prepare_rvalue(rval
);
3472 c_unparser_assignment::prepare_rvalue (string
const & op
,
3478 if (rvalue
->tok
->type
== tok_number
|| rvalue
->tok
->type
== tok_string
)
3479 // Instead of assigning the numeric or string constant to a
3480 // temporary, then assigning the temporary to the final, let's
3481 // just override the temporary with the constant.
3482 rval
.override(parent
->c_expression(rvalue
));
3484 parent
->c_assign (rval
.value(), rvalue
, "assignment");
3488 if (op
== "++" || op
== "--")
3489 // Here is part of the conversion proccess of turning "x++" to
3493 throw semantic_error ("need rvalue for assignment", tok
);
3498 c_unparser_assignment::visit_symbol (symbol
*e
)
3500 stmt_expr
block(*parent
);
3502 assert (e
->referent
!= 0);
3503 if (e
->referent
->index_types
.size() != 0)
3504 throw semantic_error ("unexpected reference to array", e
->tok
);
3506 // parent->o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
3507 exp_type ty
= rvalue
? rvalue
->type
: e
->type
;
3508 tmpvar rval
= parent
->gensym (ty
);
3509 tmpvar res
= parent
->gensym (ty
);
3511 prepare_rvalue (op
, rval
, e
->tok
);
3513 var lvar
= parent
->getvar (e
->referent
, e
->tok
);
3514 c_assignop (res
, lvar
, rval
, e
->tok
);
3516 parent
->o
->newline() << res
<< ";";
3521 c_unparser::visit_target_symbol (target_symbol
* e
)
3523 if (!e
->probe_context_var
.empty())
3524 o
->line() << "l->" << e
->probe_context_var
;
3526 throw semantic_error("cannot translate general cast expression", e
->tok
);
3531 c_unparser::visit_cast_op (cast_op
* e
)
3533 throw semantic_error("cannot translate general cast expression", e
->tok
);
3538 c_tmpcounter::load_map_indices(arrayindex
*e
)
3542 classify_indexable (e
->base
, array
, hist
);
3546 assert (array
->referent
!= 0);
3547 vardecl
* r
= array
->referent
;
3549 // One temporary per index dimension, except in the case of
3550 // number or string constants.
3551 for (unsigned i
=0; i
<r
->index_types
.size(); i
++)
3553 tmpvar ix
= parent
->gensym (r
->index_types
[i
]);
3554 if (e
->indexes
[i
]->tok
->type
== tok_number
3555 || e
->indexes
[i
]->tok
->type
== tok_string
)
3560 ix
.declare (*parent
);
3561 e
->indexes
[i
]->visit(this);
3568 c_unparser::load_map_indices(arrayindex
*e
,
3569 vector
<tmpvar
> & idx
)
3573 classify_indexable (e
->base
, array
, hist
);
3579 assert (array
->referent
!= 0);
3580 vardecl
* r
= array
->referent
;
3582 if (r
->index_types
.size() == 0 ||
3583 r
->index_types
.size() != e
->indexes
.size())
3584 throw semantic_error ("invalid array reference", e
->tok
);
3586 for (unsigned i
=0; i
<r
->index_types
.size(); i
++)
3588 if (r
->index_types
[i
] != e
->indexes
[i
]->type
)
3589 throw semantic_error ("array index type mismatch", e
->indexes
[i
]->tok
);
3591 tmpvar ix
= gensym (r
->index_types
[i
]);
3592 if (e
->indexes
[i
]->tok
->type
== tok_number
3593 || e
->indexes
[i
]->tok
->type
== tok_string
)
3594 // Instead of assigning the numeric or string constant to a
3595 // temporary, then using the temporary, let's just
3596 // override the temporary with the constant.
3597 ix
.override(c_expression(e
->indexes
[i
]));
3600 // o->newline() << "c->last_stmt = "
3601 // << lex_cast_qstring(*e->indexes[i]->tok) << ";";
3602 c_assign (ix
.value(), e
->indexes
[i
], "array index copy");
3609 assert (e
->indexes
.size() == 1);
3610 assert (e
->indexes
[0]->type
== pe_long
);
3611 tmpvar ix
= gensym (pe_long
);
3612 // o->newline() << "c->last_stmt = "
3613 // << lex_cast_qstring(*e->indexes[0]->tok) << ";";
3614 c_assign (ix
.value(), e
->indexes
[0], "array index copy");
3621 c_unparser::load_aggregate (expression
*e
, aggvar
& agg
, bool pre_agg
)
3623 symbol
*sym
= get_symbol_within_expression (e
);
3625 if (sym
->referent
->type
!= pe_stats
)
3626 throw semantic_error ("unexpected aggregate of non-statistic", sym
->tok
);
3628 var v
= getvar(sym
->referent
, e
->tok
);
3630 if (sym
->referent
->arity
== 0)
3632 // o->newline() << "c->last_stmt = " << lex_cast_qstring(*sym->tok) << ";";
3633 o
->newline() << agg
<< " = _stp_stat_get (" << v
<< ", 0);";
3637 arrayindex
*arr
= NULL
;
3638 if (!expression_is_arrayindex (e
, arr
))
3639 throw semantic_error("unexpected aggregate of non-arrayindex", e
->tok
);
3642 load_map_indices (arr
, idx
);
3643 mapvar mvar
= getmap (sym
->referent
, sym
->tok
);
3644 // o->newline() << "c->last_stmt = " << lex_cast_qstring(*sym->tok) << ";";
3645 o
->newline() << agg
<< " = " << mvar
.get(idx
, pre_agg
) << ";";
3651 c_unparser::histogram_index_check(var
& base
, tmpvar
& idx
) const
3653 return "((" + idx
.value() + " >= 0)"
3654 + " && (" + idx
.value() + " < " + base
.buckets() + "))";
3659 c_tmpcounter::visit_arrayindex (arrayindex
*e
)
3663 classify_indexable (e
->base
, array
, hist
);
3667 load_map_indices(e
);
3669 // The index-expression result.
3670 tmpvar res
= parent
->gensym (e
->type
);
3671 res
.declare (*parent
);
3678 // Note: this is a slightly tricker-than-it-looks allocation of
3679 // temporaries. The reason is that we're in the branch handling
3680 // histogram-indexing, and the histogram might be build over an
3681 // indexable entity itself. For example if we have:
3685 // foo[getpid(), geteuid()] <<< 1
3687 // print @log_hist(foo[pid, euid])[bucket]
3689 // We are looking at the @log_hist(...)[bucket] expression, so
3690 // allocating one tmpvar for calculating bucket (the "index" of
3691 // this arrayindex expression), and one tmpvar for storing the
3692 // result in, just as normal.
3694 // But we are *also* going to call load_aggregate on foo, which
3695 // will itself require tmpvars for each of its indices. Since
3696 // this is not handled by delving into the subexpression (it
3697 // would be if hist were first-class in the type system, but
3698 // it's not) we we allocate all the tmpvars used in such a
3699 // subexpression up here: first our own aggvar, then our index
3700 // (bucket) tmpvar, then all the index tmpvars of our
3701 // pe_stat-valued subexpression, then our result.
3704 // First all the stuff related to indexing into the histogram
3706 if (e
->indexes
.size() != 1)
3707 throw semantic_error("Invalid indexing of histogram", e
->tok
);
3708 tmpvar ix
= parent
->gensym (pe_long
);
3709 ix
.declare (*parent
);
3710 e
->indexes
[0]->visit(this);
3711 tmpvar res
= parent
->gensym (pe_long
);
3712 res
.declare (*parent
);
3714 // Then the aggregate, and all the tmpvars needed by our call to
3715 // load_aggregate().
3717 aggvar agg
= parent
->gensym_aggregate ();
3718 agg
.declare(*(this->parent
));
3720 symbol
*sym
= get_symbol_within_expression (hist
->stat
);
3721 var v
= parent
->getvar(sym
->referent
, sym
->tok
);
3722 if (sym
->referent
->arity
!= 0)
3724 arrayindex
*arr
= NULL
;
3725 if (!expression_is_arrayindex (hist
->stat
, arr
))
3726 throw semantic_error("expected arrayindex expression in indexed hist_op", e
->tok
);
3728 for (unsigned i
=0; i
<sym
->referent
->index_types
.size(); i
++)
3730 tmpvar ix
= parent
->gensym (sym
->referent
->index_types
[i
]);
3731 ix
.declare (*parent
);
3732 arr
->indexes
[i
]->visit(this);
3740 c_unparser::visit_arrayindex (arrayindex
* e
)
3744 classify_indexable (e
->base
, array
, hist
);
3748 // Visiting an statistic-valued array in a non-lvalue context is prohibited.
3749 if (array
->referent
->type
== pe_stats
)
3750 throw semantic_error ("statistic-valued array in rvalue context", e
->tok
);
3752 stmt_expr
block(*this);
3754 // NB: Do not adjust the order of the next few lines; the tmpvar
3755 // allocation order must remain the same between
3756 // c_unparser::visit_arrayindex and c_tmpcounter::visit_arrayindex
3759 load_map_indices (e
, idx
);
3760 tmpvar res
= gensym (e
->type
);
3762 mapvar mvar
= getmap (array
->referent
, e
->tok
);
3763 // o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
3764 c_assign (res
, mvar
.get(idx
), e
->tok
);
3766 o
->newline() << res
<< ";";
3770 // See commentary in c_tmpcounter::visit_arrayindex
3773 stmt_expr
block(*this);
3775 // NB: Do not adjust the order of the next few lines; the tmpvar
3776 // allocation order must remain the same between
3777 // c_unparser::visit_arrayindex and c_tmpcounter::visit_arrayindex
3780 load_map_indices (e
, idx
);
3781 tmpvar res
= gensym (e
->type
);
3783 aggvar agg
= gensym_aggregate ();
3785 // These should have faulted during elaboration if not true.
3786 assert(idx
.size() == 1);
3787 assert(idx
[0].type() == pe_long
);
3789 symbol
*sym
= get_symbol_within_expression (hist
->stat
);
3792 if (sym
->referent
->arity
< 1)
3793 v
= new var(getvar(sym
->referent
, e
->tok
));
3795 v
= new mapvar(getmap(sym
->referent
, e
->tok
));
3797 v
->assert_hist_compatible(*hist
);
3799 if (aggregations_active
.count(v
->value()))
3800 load_aggregate(hist
->stat
, agg
, true);
3802 load_aggregate(hist
->stat
, agg
, false);
3804 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
3806 // PR 2142+2610: empty aggregates
3807 o
->newline() << "if (unlikely (" << agg
.value() << " == NULL)"
3808 << " || " << agg
.value() << "->count == 0) {";
3809 o
->newline(1) << "c->last_error = \"empty aggregate\";";
3810 o
->newline() << "goto out;";
3811 o
->newline(-1) << "} else {";
3812 o
->newline(1) << "if (" << histogram_index_check(*v
, idx
[0]) << ")";
3813 o
->newline(1) << res
<< " = " << agg
<< "->histogram[" << idx
[0] << "];";
3814 o
->newline(-1) << "else {";
3815 o
->newline(1) << "c->last_error = \"histogram index out of range\";";
3816 o
->newline() << "goto out;";
3817 o
->newline(-1) << "}";
3819 o
->newline(-1) << "}";
3820 o
->newline() << res
<< ";";
3828 c_tmpcounter_assignment::visit_arrayindex (arrayindex
*e
)
3832 classify_indexable (e
->base
, array
, hist
);
3836 parent
->load_map_indices(e
);
3838 // The expression rval, lval, and result.
3839 exp_type ty
= rvalue
? rvalue
->type
: e
->type
;
3840 tmpvar rval
= parent
->parent
->gensym (ty
);
3841 tmpvar lval
= parent
->parent
->gensym (ty
);
3842 tmpvar res
= parent
->parent
->gensym (ty
);
3844 prepare_rvalue(rval
);
3845 lval
.declare (*(parent
->parent
));
3848 res
.declare (*(parent
->parent
));
3854 throw semantic_error("cannot assign to histogram buckets", e
->tok
);
3860 c_unparser_assignment::visit_arrayindex (arrayindex
*e
)
3864 classify_indexable (e
->base
, array
, hist
);
3869 stmt_expr
block(*parent
);
3871 translator_output
*o
= parent
->o
;
3873 if (array
->referent
->index_types
.size() == 0)
3874 throw semantic_error ("unexpected reference to scalar", e
->tok
);
3876 // nb: Do not adjust the order of the next few lines; the tmpvar
3877 // allocation order must remain the same between
3878 // c_unparser_assignment::visit_arrayindex and
3879 // c_tmpcounter_assignment::visit_arrayindex
3882 parent
->load_map_indices (e
, idx
);
3883 exp_type ty
= rvalue
? rvalue
->type
: e
->type
;
3884 tmpvar rvar
= parent
->gensym (ty
);
3885 tmpvar lvar
= parent
->gensym (ty
);
3886 tmpvar res
= parent
->gensym (ty
);
3888 // NB: because these expressions are nestable, emit this construct
3890 // ({ tmp0=(idx0); ... tmpN=(idxN); rvar=(rhs); lvar; res;
3892 // lvar = get (array,idx0...N); // if necessary
3893 // assignop (res, lvar, rvar);
3894 // set (array, idx0...N, lvar);
3898 // we store all indices in temporary variables to avoid nasty
3899 // reentrancy issues that pop up with nested expressions:
3900 // e.g. ++a[a[c]=5] could deadlock
3903 // There is an exception to the above form: if we're doign a <<< assigment to
3904 // a statistic-valued map, there's a special form we follow:
3906 // ({ tmp0=(idx0); ... tmpN=(idxN); rvar=(rhs);
3907 // *no need to* lock (array);
3908 // _stp_map_add_stat (array, idx0...N, rvar);
3909 // *no need to* unlock (array);
3912 // To simplify variable-allocation rules, we assign rvar to lvar and
3913 // res in this block as well, even though they are technically
3916 prepare_rvalue (op
, rvar
, e
->tok
);
3920 assert (e
->type
== pe_stats
);
3921 assert (rvalue
->type
== pe_long
);
3923 mapvar mvar
= parent
->getmap (array
->referent
, e
->tok
);
3924 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
3925 o
->newline() << mvar
.add (idx
, rvar
) << ";";
3927 // no need for these dummy assignments
3928 // o->newline() << lvar << " = " << rvar << ";";
3929 // o->newline() << res << " = " << rvar << ";";
3933 mapvar mvar
= parent
->getmap (array
->referent
, e
->tok
);
3934 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
3935 if (op
!= "=") // don't bother fetch slot if we will just overwrite it
3936 parent
->c_assign (lvar
, mvar
.get(idx
), e
->tok
);
3937 c_assignop (res
, lvar
, rvar
, e
->tok
);
3938 o
->newline() << mvar
.set (idx
, lvar
) << ";";
3941 o
->newline() << res
<< ";";
3945 throw semantic_error("cannot assign to histogram buckets", e
->tok
);
3951 c_tmpcounter::visit_functioncall (functioncall
*e
)
3953 assert (e
->referent
!= 0);
3954 functiondecl
* r
= e
->referent
;
3955 // one temporary per argument, unless literal numbers or strings
3956 for (unsigned i
=0; i
<r
->formal_args
.size(); i
++)
3958 tmpvar t
= parent
->gensym (r
->formal_args
[i
]->type
);
3959 if (e
->args
[i
]->tok
->type
!= tok_number
3960 && e
->args
[i
]->tok
->type
!= tok_string
)
3961 t
.declare (*parent
);
3962 e
->args
[i
]->visit (this);
3968 c_unparser::visit_functioncall (functioncall
* e
)
3970 assert (e
->referent
!= 0);
3971 functiondecl
* r
= e
->referent
;
3973 if (r
->formal_args
.size() != e
->args
.size())
3974 throw semantic_error ("invalid length argument list", e
->tok
);
3976 stmt_expr
block(*this);
3978 // NB: we store all actual arguments in temporary variables,
3979 // to avoid colliding sharing of context variables with
3980 // nested function calls: f(f(f(1)))
3982 // compute actual arguments
3985 for (unsigned i
=0; i
<e
->args
.size(); i
++)
3987 tmpvar t
= gensym(e
->args
[i
]->type
);
3989 if (r
->formal_args
[i
]->type
!= e
->args
[i
]->type
)
3990 throw semantic_error ("function argument type mismatch",
3991 e
->args
[i
]->tok
, "vs", r
->formal_args
[i
]->tok
);
3993 if (e
->args
[i
]->tok
->type
== tok_number
3994 || e
->args
[i
]->tok
->type
== tok_string
)
3995 t
.override(c_expression(e
->args
[i
]));
3998 // o->newline() << "c->last_stmt = "
3999 // << lex_cast_qstring(*e->args[i]->tok) << ";";
4000 c_assign (t
.value(), e
->args
[i
],
4001 "function actual argument evaluation");
4006 // copy in actual arguments
4007 for (unsigned i
=0; i
<e
->args
.size(); i
++)
4009 if (r
->formal_args
[i
]->type
!= e
->args
[i
]->type
)
4010 throw semantic_error ("function argument type mismatch",
4011 e
->args
[i
]->tok
, "vs", r
->formal_args
[i
]->tok
);
4013 c_assign ("c->locals[c->nesting+1].function_" +
4014 c_varname (r
->name
) + "." +
4015 c_varname (r
->formal_args
[i
]->name
),
4018 "function actual argument copy",
4023 o
->newline() << "function_" << c_varname (r
->name
) << " (c);";
4024 o
->newline() << "if (unlikely(c->last_error)) goto out;";
4026 // return result from retvalue slot
4027 if (r
->type
== pe_unknown
)
4028 // If we passed typechecking, then nothing will use this return value
4029 o
->newline() << "(void) 0;";
4031 o
->newline() << "c->locals[c->nesting+1]"
4032 << ".function_" << c_varname (r
->name
)
4037 c_tmpcounter::visit_print_format (print_format
* e
)
4041 symbol
*sym
= get_symbol_within_expression (e
->hist
->stat
);
4042 var v
= parent
->getvar(sym
->referent
, sym
->tok
);
4043 aggvar agg
= parent
->gensym_aggregate ();
4045 agg
.declare(*(this->parent
));
4047 if (sym
->referent
->arity
!= 0)
4049 // One temporary per index dimension.
4050 for (unsigned i
=0; i
<sym
->referent
->index_types
.size(); i
++)
4052 arrayindex
*arr
= NULL
;
4053 if (!expression_is_arrayindex (e
->hist
->stat
, arr
))
4054 throw semantic_error("expected arrayindex expression in printed hist_op", e
->tok
);
4056 tmpvar ix
= parent
->gensym (sym
->referent
->index_types
[i
]);
4057 ix
.declare (*parent
);
4058 arr
->indexes
[i
]->visit(this);
4064 // One temporary per argument
4065 for (unsigned i
=0; i
< e
->args
.size(); i
++)
4067 tmpvar t
= parent
->gensym (e
->args
[i
]->type
);
4068 if (e
->args
[i
]->type
== pe_unknown
)
4070 throw semantic_error("unknown type of arg to print operator",
4074 if (e
->args
[i
]->tok
->type
!= tok_number
4075 && e
->args
[i
]->tok
->type
!= tok_string
)
4076 t
.declare (*parent
);
4077 e
->args
[i
]->visit (this);
4081 exp_type ty
= e
->print_to_stream
? pe_long
: pe_string
;
4082 tmpvar res
= parent
->gensym (ty
);
4083 if (ty
== pe_string
)
4084 res
.declare (*parent
);
4090 c_unparser::visit_print_format (print_format
* e
)
4092 // Print formats can contain a general argument list *or* a special
4093 // type of argument which gets its own processing: a single,
4094 // non-format-string'ed, histogram-type stat_op expression.
4098 stmt_expr
block(*this);
4099 symbol
*sym
= get_symbol_within_expression (e
->hist
->stat
);
4100 aggvar agg
= gensym_aggregate ();
4103 if (sym
->referent
->arity
< 1)
4104 v
= new var(getvar(sym
->referent
, e
->tok
));
4106 v
= new mapvar(getmap(sym
->referent
, e
->tok
));
4108 v
->assert_hist_compatible(*e
->hist
);
4111 if (aggregations_active
.count(v
->value()))
4112 load_aggregate(e
->hist
->stat
, agg
, true);
4114 load_aggregate(e
->hist
->stat
, agg
, false);
4116 // PR 2142+2610: empty aggregates
4117 o
->newline() << "if (unlikely (" << agg
.value() << " == NULL)"
4118 << " || " << agg
.value() << "->count == 0) {";
4119 o
->newline(1) << "c->last_error = \"empty aggregate\";";
4120 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
4121 o
->newline() << "goto out;";
4122 o
->newline(-1) << "} else";
4123 o
->newline(1) << "_stp_stat_print_histogram (" << v
->hist() << ", " << agg
.value() << ");";
4131 stmt_expr
block(*this);
4133 // Compute actual arguments
4136 for (unsigned i
=0; i
<e
->args
.size(); i
++)
4138 tmpvar t
= gensym(e
->args
[i
]->type
);
4141 // o->newline() << "c->last_stmt = "
4142 // << lex_cast_qstring(*e->args[i]->tok) << ";";
4144 // If we've got a numeric or string constant, instead of
4145 // assigning the numeric or string constant to a temporary,
4146 // then passing the temporary to _stp_printf/_stp_snprintf,
4147 // let's just override the temporary with the constant.
4148 if (e
->args
[i
]->tok
->type
== tok_number
4149 || e
->args
[i
]->tok
->type
== tok_string
)
4150 tmp
[i
].override(c_expression(e
->args
[i
]));
4152 c_assign (t
.value(), e
->args
[i
],
4153 "print format actual argument evaluation");
4156 std::vector
<print_format::format_component
> components
;
4158 if (e
->print_with_format
)
4160 components
= e
->components
;
4164 // Synthesize a print-format string if the user didn't
4165 // provide one; the synthetic string simply contains one
4166 // directive for each argument.
4167 for (unsigned i
= 0; i
< e
->args
.size(); ++i
)
4169 if (i
> 0 && e
->print_with_delim
)
4170 components
.push_back (e
->delimiter
);
4171 print_format::format_component curr
;
4173 switch (e
->args
[i
]->type
)
4176 throw semantic_error("cannot print unknown expression type", e
->args
[i
]->tok
);
4178 throw semantic_error("cannot print a raw stats object", e
->args
[i
]->tok
);
4180 curr
.type
= print_format::conv_signed_decimal
;
4183 curr
.type
= print_format::conv_string
;
4186 components
.push_back (curr
);
4189 if (e
->print_with_newline
)
4191 print_format::format_component curr
;
4193 curr
.type
= print_format::conv_literal
;
4194 curr
.literal_string
= "\\n";
4195 components
.push_back (curr
);
4199 // Allocate the result
4200 exp_type ty
= e
->print_to_stream
? pe_long
: pe_string
;
4201 tmpvar res
= gensym (ty
);
4204 string format_string
= print_format::components_to_string(components
);
4205 if (tmp
.size() == 0 || (tmp
.size() == 1 && format_string
== "%s"))
4207 else if (tmp
.size() == 1
4208 && e
->args
[0]->tok
->type
== tok_string
4209 && format_string
== "%s\\n")
4212 tmp
[0].override(tmp
[0].value() + "\"\\n\"");
4213 components
[0].type
= print_format::conv_literal
;
4216 // Make the [s]printf call...
4218 // Generate code to check that any pointer arguments are actually accessible. */
4220 for (unsigned i
= 0; i
< components
.size(); ++i
) {
4221 if (components
[i
].type
== print_format::conv_literal
)
4224 /* Take note of the width and precision arguments, if any. */
4225 int width_ix
= -1, prec_ix
= -1;
4226 if (components
[i
].widthtype
== print_format::width_dynamic
)
4227 width_ix
= arg_ix
++;
4228 if (components
[i
].prectype
== print_format::prec_dynamic
)
4231 /* Generate a noop call to deref_buffer for %m. */
4232 if (components
[i
].type
== print_format::conv_memory
4233 || components
[i
].type
== print_format::conv_memory_hex
) {
4234 this->probe_or_function_needs_deref_fault_handler
= true;
4235 o
->newline() << "deref_buffer (0, " << tmp
[arg_ix
].value() << ", ";
4240 o
->line() << tmp
[prec_ix
].value();
4249 if (e
->print_to_stream
)
4253 o
->newline() << "_stp_print_char (";
4255 o
->line() << tmp
[0].value() << ");";
4257 o
->line() << '"' << format_string
<< "\");";
4262 o
->newline() << "_stp_print (";
4264 o
->line() << tmp
[0].value() << ");";
4266 o
->line() << '"' << format_string
<< "\");";
4270 // We'll just hardcode the result of 0 instead of using the
4272 res
.override("((int64_t)0LL)");
4273 o
->newline() << "_stp_printf (";
4276 o
->newline() << "_stp_snprintf (" << res
.value() << ", MAXSTRINGLEN, ";
4278 o
->line() << '"' << format_string
<< '"';
4280 /* Generate the actual arguments. Make sure that they match the expected type of the
4281 format specifier. */
4283 for (unsigned i
= 0; i
< components
.size(); ++i
) {
4284 if (components
[i
].type
== print_format::conv_literal
)
4287 /* Cast the width and precision arguments, if any, to 'int'. */
4288 if (components
[i
].widthtype
== print_format::width_dynamic
)
4289 o
->line() << ", (int)" << tmp
[arg_ix
++].value();
4290 if (components
[i
].prectype
== print_format::prec_dynamic
)
4291 o
->line() << ", (int)" << tmp
[arg_ix
++].value();
4293 /* The type of the %m argument is 'char*'. */
4294 if (components
[i
].type
== print_format::conv_memory
4295 || components
[i
].type
== print_format::conv_memory_hex
)
4296 o
->line() << ", (char*)(uintptr_t)" << tmp
[arg_ix
++].value();
4297 /* The type of the %c argument is 'int'. */
4298 else if (components
[i
].type
== print_format::conv_char
)
4299 o
->line() << ", (int)" << tmp
[arg_ix
++].value();
4300 else if (arg_ix
< (int) tmp
.size())
4301 o
->line() << ", " << tmp
[arg_ix
++].value();
4305 o
->newline() << res
.value() << ";";
4311 c_tmpcounter::visit_stat_op (stat_op
* e
)
4313 symbol
*sym
= get_symbol_within_expression (e
->stat
);
4314 var v
= parent
->getvar(sym
->referent
, e
->tok
);
4315 aggvar agg
= parent
->gensym_aggregate ();
4316 tmpvar res
= parent
->gensym (pe_long
);
4318 agg
.declare(*(this->parent
));
4319 res
.declare(*(this->parent
));
4321 if (sym
->referent
->arity
!= 0)
4323 // One temporary per index dimension.
4324 for (unsigned i
=0; i
<sym
->referent
->index_types
.size(); i
++)
4326 // Sorry about this, but with no dynamic_cast<> and no
4327 // constructor patterns, this is how things work.
4328 arrayindex
*arr
= NULL
;
4329 if (!expression_is_arrayindex (e
->stat
, arr
))
4330 throw semantic_error("expected arrayindex expression in stat_op of array", e
->tok
);
4332 tmpvar ix
= parent
->gensym (sym
->referent
->index_types
[i
]);
4333 ix
.declare (*parent
);
4334 arr
->indexes
[i
]->visit(this);
4340 c_unparser::visit_stat_op (stat_op
* e
)
4342 // Stat ops can be *applied* to two types of expression:
4344 // 1. An arrayindex expression on a pe_stats-valued array.
4346 // 2. A symbol of type pe_stats.
4348 // FIXME: classify the expression the stat_op is being applied to,
4349 // call appropriate stp_get_stat() / stp_pmap_get_stat() helper,
4350 // then reach into resultant struct stat_data.
4352 // FIXME: also note that summarizing anything is expensive, and we
4353 // really ought to pass a timeout handler into the summary routine,
4354 // check its response, possibly exit if it ran out of cycles.
4357 stmt_expr
block(*this);
4358 symbol
*sym
= get_symbol_within_expression (e
->stat
);
4359 aggvar agg
= gensym_aggregate ();
4360 tmpvar res
= gensym (pe_long
);
4361 var v
= getvar(sym
->referent
, e
->tok
);
4363 if (aggregations_active
.count(v
.value()))
4364 load_aggregate(e
->stat
, agg
, true);
4366 load_aggregate(e
->stat
, agg
, false);
4368 // PR 2142+2610: empty aggregates
4369 if (e
->ctype
== sc_count
)
4371 o
->newline() << "if (unlikely (" << agg
.value() << " == NULL))";
4373 c_assign(res
, "0", e
->tok
);
4378 o
->newline() << "if (unlikely (" << agg
.value() << " == NULL)"
4379 << " || " << agg
.value() << "->count == 0) {";
4380 o
->newline(1) << "c->last_error = \"empty aggregate\";";
4381 o
->newline() << "c->last_stmt = " << lex_cast_qstring(*e
->tok
) << ";";
4382 o
->newline() << "goto out;";
4383 o
->newline(-1) << "}";
4385 o
->newline() << "else";
4390 c_assign(res
, ("_stp_div64(NULL, " + agg
.value() + "->sum, "
4391 + agg
.value() + "->count)"),
4395 c_assign(res
, agg
.value() + "->count", e
->tok
);
4398 c_assign(res
, agg
.value() + "->sum", e
->tok
);
4401 c_assign(res
, agg
.value() + "->min", e
->tok
);
4404 c_assign(res
, agg
.value() + "->max", e
->tok
);
4409 o
->newline() << res
<< ";";
4415 c_unparser::visit_hist_op (hist_op
*)
4417 // Hist ops can only occur in a limited set of circumstances:
4419 // 1. Inside an arrayindex expression, as the base referent. See
4420 // c_unparser::visit_arrayindex for handling of this case.
4422 // 2. Inside a foreach statement, as the base referent. See
4423 // c_unparser::visit_foreach_loop for handling this case.
4425 // 3. Inside a print_format expression, as the sole argument. See
4426 // c_unparser::visit_print_format for handling this case.
4428 // Note that none of these cases involves the c_unparser ever
4429 // visiting this node. We should not get here.
4436 struct unwindsym_dump_context
4438 systemtap_session
& session
;
4440 unsigned stp_module_index
;
4441 set
<string
> undone_unwindsym_modules
;
4445 // Get the .debug_frame section for the given module.
4446 // l will be set to the length of the size of the unwind data if found.
4447 static void *get_unwind_data (Dwfl_Module
*m
, size_t *l
)
4449 Dwarf_Addr bias
= 0;
4451 GElf_Ehdr
*ehdr
, ehdr_mem
;
4452 GElf_Shdr
*shdr
, shdr_mem
;
4453 Elf_Scn
*scn
= NULL
;
4454 Elf_Data
*data
= NULL
;
4456 dw
= dwfl_module_getdwarf(m
, &bias
);
4459 Elf
*elf
= dwarf_getelf(dw
);
4460 ehdr
= gelf_getehdr(elf
, &ehdr_mem
);
4461 while ((scn
= elf_nextscn(elf
, scn
)))
4463 shdr
= gelf_getshdr(scn
, &shdr_mem
);
4464 if (strcmp(elf_strptr(elf
, ehdr
->e_shstrndx
, shdr
->sh_name
),
4465 ".debug_frame") == 0)
4467 data
= elf_rawdata(scn
, NULL
);
4483 dump_unwindsyms (Dwfl_Module
*m
,
4484 void **userdata
__attribute__ ((unused
)),
4489 unwindsym_dump_context
* c
= (unwindsym_dump_context
*) arg
;
4491 unsigned stpmod_idx
= c
->stp_module_index
;
4493 string modname
= name
;
4495 if (pending_interrupts
)
4496 return DWARF_CB_ABORT
;
4498 // skip modules/files we're not actually interested in
4499 if (c
->session
.unwindsym_modules
.find(modname
) == c
->session
.unwindsym_modules
.end())
4502 c
->stp_module_index
++;
4504 if (c
->session
.verbose
> 1)
4505 clog
<< "dump_unwindsyms " << name
4506 << " index=" << stpmod_idx
4507 << " base=0x" << hex
<< base
<< dec
<< endl
;
4509 // We want to extract several bits of information:
4511 // - parts of the program-header that map the file's physical offsets to the text section
4512 // - section table: just a list of section (relocation) base addresses
4513 // - symbol table of the text-like sections, with all addresses relativized to each base
4514 // - the contents of .debug_frame section, for unwinding purposes
4516 // In the future, we'll also care about data symbols.
4518 int syments
= dwfl_module_getsymtab(m
);
4519 dwfl_assert ("Getting symbol table for " + modname
, syments
>= 0);
4521 //extract build-id from debuginfo file
4522 int build_id_len
= 0;
4523 unsigned char *build_id_bits
;
4524 GElf_Addr build_id_vaddr
;
4526 if ((build_id_len
=dwfl_module_build_id(m
,
4527 (const unsigned char **)&build_id_bits
,
4528 &build_id_vaddr
)) > 0)
4530 // Enable workaround for elfutils dwfl bug.
4531 // see https://bugzilla.redhat.com/show_bug.cgi?id=465872
4532 // and http://sourceware.org/ml/systemtap/2008-q4/msg00579.html
4533 #ifdef _ELFUTILS_PREREQ
4534 #if _ELFUTILS_PREREQ(0,138)
4535 // Let's standardize to the buggy "end of build-id bits" behavior.
4536 build_id_vaddr
+= build_id_len
;
4538 #if !_ELFUTILS_PREREQ(0,141)
4539 #define NEED_ELFUTILS_BUILDID_WORKAROUND
4542 #define NEED_ELFUTILS_BUILDID_WORKAROUND
4545 // And check for another workaround needed.
4546 // see https://bugzilla.redhat.com/show_bug.cgi?id=489439
4547 // and http://sourceware.org/ml/systemtap/2009-q1/msg00513.html
4548 #ifdef NEED_ELFUTILS_BUILDID_WORKAROUND
4549 if (build_id_vaddr
< base
&& dwfl_module_relocations (m
) == 1)
4551 GElf_Addr main_bias
;
4552 dwfl_module_getelf (m
, &main_bias
);
4553 build_id_vaddr
+= main_bias
;
4556 if (c
->session
.verbose
> 1)
4558 clog
<< "Found build-id in " << name
4559 << ", length " << build_id_len
;
4560 clog
<< ", end at 0x" << hex
<< build_id_vaddr
4565 // Use end as sanity check when resolving symbol addresses.
4567 dwfl_module_info (m
, NULL
, NULL
, &end
, NULL
, NULL
, NULL
, NULL
);
4569 // Look up the relocation basis for symbols
4570 int n
= dwfl_module_relocations (m
);
4572 dwfl_assert ("dwfl_module_relocations", n
>= 0);
4575 // XXX: unfortunate duplication with tapsets.cxx:emit_address()
4577 typedef map
<Dwarf_Addr
,const char*> addrmap_t
; // NB: plain map, sorted by address
4578 vector
<string
> seclist
; // encountered relocation bases (section names)
4579 map
<unsigned, addrmap_t
> addrmap
; // per-relocation-base sorted addrmap
4581 Dwarf_Addr extra_offset
= 0;
4583 for (int i
= 0; i
< syments
; ++i
)
4587 const char *name
= dwfl_module_getsym(m
, i
, &sym
, &shndxp
);
4590 // NB: Yey, we found the kernel's _stext value.
4591 // Sess.sym_stext may be unset (0) at this point, since
4592 // there may have been no kernel probes set. We could
4593 // use tapsets.cxx:lookup_symbol_address(), but then
4594 // we're already iterating over the same data here...
4595 if (modname
== "kernel" && !strcmp(name
, "_stext"))
4598 extra_offset
= sym
.st_value
;
4599 ki
= dwfl_module_relocate_address (m
, &extra_offset
);
4600 dwfl_assert ("dwfl_module_relocate_address extra_offset",
4602 // Sadly dwfl_module_relocate_address is broken on
4603 // elfutils < 0.138, so we need to adjust for the module
4604 // base address outself. (see also below).
4605 extra_offset
= sym
.st_value
- base
;
4606 if (c
->session
.verbose
> 2)
4607 clog
<< "Found kernel _stext extra offset 0x" << hex
<< extra_offset
<< dec
<< endl
;
4610 // We are only interested in "real" symbols.
4611 // We omit symbols that have suspicious addresses (before base,
4613 if ((GELF_ST_TYPE (sym
.st_info
) == STT_FUNC
||
4614 GELF_ST_TYPE (sym
.st_info
) == STT_OBJECT
) // PR10000: also need .data
4615 && !(sym
.st_shndx
== SHN_UNDEF
// Value undefined,
4616 || shndxp
== (GElf_Word
) -1 // in a non-allocated section,
4617 || sym
.st_value
>= end
// beyond current module,
4618 || sym
.st_value
< base
)) // before first section.
4620 Dwarf_Addr sym_addr
= sym
.st_value
;
4621 const char *secname
= NULL
;
4623 if (n
> 0) // only try to relocate if there exist relocation bases
4625 Dwarf_Addr save_addr
= sym_addr
;
4626 int ki
= dwfl_module_relocate_address (m
, &sym_addr
);
4627 dwfl_assert ("dwfl_module_relocate_address", ki
>= 0);
4628 secname
= dwfl_module_relocation_info (m
, ki
, NULL
);
4630 // For ET_DYN files (secname == "") we do ignore the
4631 // dwfl_module_relocate_address adjustment. libdwfl
4632 // up to 0.137 would substract the wrong bias. So we do
4633 // it ourself, it is always just the module base address
4635 if (ki
== 0 && secname
!= NULL
&& secname
[0] == '\0')
4636 sym_addr
= save_addr
- base
;
4639 if (n
== 1 && modname
== "kernel")
4641 // This is a symbol within a (possibly relocatable)
4644 // We only need the function symbols to identify kernel-mode
4645 // PC's, so we omit undefined or "fake" absolute addresses.
4646 // These fake absolute addresses occur in some older i386
4647 // kernels to indicate they are vDSO symbols, not real
4648 // functions in the kernel. We also omit symbols that have
4649 if (GELF_ST_TYPE (sym
.st_info
) == STT_FUNC
4650 && sym
.st_shndx
== SHN_ABS
)
4654 // NB: don't subtract session.sym_stext, which could be inconveniently NULL.
4655 // Instead, sym_addr will get compensated later via extra_offset.
4659 assert (secname
!= NULL
);
4660 // secname adequately set
4662 // NB: it may be an empty string for ET_DYN objects
4663 // like shared libraries, as their relocation base
4665 if (secname
[0] == '\0')
4666 secname
= ".dynamic";
4671 // sym_addr is absolute, as it must be since there are no relocation bases
4672 secname
= ".absolute"; // sentinel
4675 // Compute our section number
4677 for (secidx
=0; secidx
<seclist
.size(); secidx
++)
4678 if (seclist
[secidx
]==secname
) break;
4680 if (secidx
== seclist
.size()) // new section name
4681 seclist
.push_back (secname
);
4683 (addrmap
[secidx
])[sym_addr
] = name
;
4688 // Add unwind data to be included if it exists for this module.
4690 void *unwind
= get_unwind_data (m
, &len
);
4693 c
->output
<< "#if defined(STP_USE_DWARF_UNWINDER) && defined(STP_NEED_UNWIND_DATA)\n";
4694 c
->output
<< "static uint8_t _stp_module_" << stpmod_idx
4695 << "_unwind_data[] = \n";
4697 for (size_t i
= 0; i
< len
; i
++)
4699 int h
= ((uint8_t *)unwind
)[i
];
4700 c
->output
<< "0x" << hex
<< h
<< dec
<< ",";
4701 if ((i
+ 1) % 16 == 0)
4702 c
->output
<< "\n" << " ";
4704 c
->output
<< "};\n";
4705 c
->output
<< "#endif /* STP_USE_DWARF_UNWINDER && STP_NEED_UNWIND_DATA */\n";
4709 // There would be only a small benefit to warning. A user
4710 // likely can't do anything about this; backtraces for the
4711 // affected module would just get all icky heuristicy.
4712 // So only report in verbose mode.
4713 if (c
->session
.verbose
> 2)
4714 c
->session
.print_warning ("No unwind data for " + modname
4715 + ", " + dwfl_errmsg (-1));
4718 for (unsigned secidx
= 0; secidx
< seclist
.size(); secidx
++)
4720 c
->output
<< "static struct _stp_symbol "
4721 << "_stp_module_" << stpmod_idx
<< "_symbols_" << secidx
<< "[] = {\n";
4723 // Only include symbols if they will be used
4724 c
->output
<< "#ifdef STP_NEED_SYMBOL_DATA\n";
4726 // We write out a *sorted* symbol table, so the runtime doesn't have to sort them later.
4727 for (addrmap_t::iterator it
= addrmap
[secidx
].begin(); it
!= addrmap
[secidx
].end(); it
++)
4729 if (it
->first
< extra_offset
)
4730 continue; // skip symbols that occur before our chosen base address
4732 c
->output
<< " { 0x" << hex
<< it
->first
-extra_offset
<< dec
4733 << ", " << lex_cast_qstring (it
->second
) << " },\n";
4736 c
->output
<< "#endif /* STP_NEED_SYMBOL_DATA */\n";
4738 c
->output
<< "};\n";
4741 c
->output
<< "static struct _stp_section _stp_module_" << stpmod_idx
<< "_sections[] = {\n";
4742 for (unsigned secidx
= 0; secidx
< seclist
.size(); secidx
++)
4745 << ".name = " << lex_cast_qstring(seclist
[secidx
]) << ",\n"
4746 << ".symbols = _stp_module_" << stpmod_idx
<< "_symbols_" << secidx
<< ",\n"
4747 << ".num_symbols = sizeof(_stp_module_" << stpmod_idx
<< "_symbols_" << secidx
<< ")/sizeof(struct _stp_symbol)\n"
4750 c
->output
<< "};\n";
4752 c
->output
<< "static struct _stp_module _stp_module_" << stpmod_idx
<< " = {\n";
4753 c
->output
<< ".name = " << lex_cast_qstring (modname
) << ", \n";
4755 // Get the canonical path of the main file for comparison at runtime.
4756 // When given directly by the user through -d or in case of the kernel
4757 // name and path might differ. path should be used for matching.
4758 const char *mainfile
;
4759 dwfl_module_info (m
, NULL
, NULL
, NULL
, NULL
, NULL
, &mainfile
, NULL
);
4760 mainfile
= canonicalize_file_name(mainfile
);
4761 c
->output
<< ".path = " << lex_cast_qstring (mainfile
) << ",\n";
4763 c
->output
<< ".dwarf_module_base = 0x" << hex
<< base
<< dec
<< ", \n";
4767 c
->output
<< "#if defined(STP_USE_DWARF_UNWINDER) && defined(STP_NEED_UNWIND_DATA)\n";
4768 c
->output
<< ".unwind_data = "
4769 << "_stp_module_" << stpmod_idx
<< "_unwind_data, \n";
4770 c
->output
<< ".unwind_data_len = " << len
<< ", \n";
4771 c
->output
<< "#else\n";
4774 c
->output
<< ".unwind_data = NULL,\n";
4775 c
->output
<< ".unwind_data_len = 0,\n";
4778 c
->output
<< "#endif /* STP_USE_DWARF_UNWINDER && STP_NEED_UNWIND_DATA*/\n";
4780 c
->output
<< ".unwind_hdr = NULL,\n";
4781 c
->output
<< ".unwind_hdr_len = 0,\n";
4782 c
->output
<< ".unwind_is_ehframe = 0,\n";
4784 c
->output
<< ".sections = _stp_module_" << stpmod_idx
<< "_sections" << ",\n";
4785 c
->output
<< ".num_sections = sizeof(_stp_module_" << stpmod_idx
<< "_sections)/"
4786 << "sizeof(struct _stp_section),\n";
4788 if (build_id_len
> 0) {
4789 c
->output
<< ".build_id_bits = \"" ;
4790 for (int j
=0; j
<build_id_len
;j
++)
4791 c
->output
<< "\\x" << hex
4792 << (unsigned short) *(build_id_bits
+j
) << dec
;
4794 c
->output
<< "\",\n";
4795 c
->output
<< ".build_id_len = " << build_id_len
<< ",\n";
4797 /* XXX: kernel data boot-time relocation works differently from text.
4798 This hack disables relocation altogether, but that's not necessarily
4799 correct either. We may instead need a relocation basis different
4800 from _stext, such as __start_notes. */
4801 if (modname
== "kernel")
4802 c
->output
<< ".build_id_offset = 0x" << hex
<< build_id_vaddr
4805 c
->output
<< ".build_id_offset = 0x" << hex
4806 << build_id_vaddr
- base
4809 c
->output
<< ".build_id_len = 0,\n";
4811 //initialize the note section representing unloaded
4812 c
->output
<< ".notes_sect = 0,\n";
4814 c
->output
<< "};\n\n";
4816 c
->undone_unwindsym_modules
.erase (modname
);
4822 // Emit symbol table & unwind data, plus any calls needed to register
4823 // them with the runtime.
4826 emit_symbol_data (systemtap_session
& s
)
4828 string symfile
= "stap-symbols.h";
4830 s
.op
->newline() << "#include " << lex_cast_qstring (symfile
);
4832 ofstream
kallsyms_out ((s
.tmpdir
+ "/" + symfile
).c_str());
4834 unwindsym_dump_context ctx
= { s
, kallsyms_out
, 0, s
.unwindsym_modules
};
4836 // XXX: copied from tapsets.cxx dwflpp::, sadly
4837 static const char *debuginfo_path_arr
= "+:.debug:/usr/lib/debug:build";
4838 static const char *debuginfo_env_arr
= getenv("SYSTEMTAP_DEBUGINFO_PATH");
4839 static const char *debuginfo_path
= (debuginfo_env_arr
?: debuginfo_path_arr
);
4841 // ---- step 1: process any kernel modules listed
4842 static const Dwfl_Callbacks kernel_callbacks
=
4844 dwfl_linux_kernel_find_elf
,
4845 dwfl_standard_find_debuginfo
,
4846 dwfl_offline_section_address
,
4847 (char **) & debuginfo_path
4850 Dwfl
*dwfl
= dwfl_begin (&kernel_callbacks
);
4852 throw semantic_error ("cannot open dwfl");
4853 dwfl_report_begin (dwfl
);
4855 // We have a problem with -r REVISION vs -r BUILDDIR here. If
4856 // we're running against a fedora/rhel style kernel-debuginfo
4857 // tree, s.kernel_build_tree is not the place where the unstripped
4858 // vmlinux will be installed. Rather, it's over yonder at
4859 // /usr/lib/debug/lib/modules/$REVISION/. It seems that there is
4860 // no way to set the dwfl_callback.debuginfo_path and always
4861 // passs the plain kernel_release here. So instead we have to
4862 // hard-code this magic here.
4863 string elfutils_kernel_path
;
4864 if (s
.kernel_build_tree
== string("/lib/modules/" + s
.kernel_release
+ "/build"))
4865 elfutils_kernel_path
= s
.kernel_release
;
4867 elfutils_kernel_path
= s
.kernel_build_tree
;
4869 int rc
= dwfl_linux_kernel_report_offline (dwfl
,
4870 elfutils_kernel_path
.c_str(),
4871 NULL
/* XXX: filtering callback */);
4872 dwfl_report_end (dwfl
, NULL
, NULL
);
4873 if (rc
== 0) // tolerate missing data; will warn user about it anyway
4878 if (pending_interrupts
) return;
4879 if (ctx
.undone_unwindsym_modules
.empty()) break;
4880 off
= dwfl_getmodules (dwfl
, &dump_unwindsyms
, (void *) &ctx
, 0);
4883 dwfl_assert("dwfl_getmodules", off
== 0);
4888 // ---- step 2: process any user modules (files) listed
4889 // XXX: see dwflpp::setup_user.
4890 static const Dwfl_Callbacks user_callbacks
=
4892 NULL
, /* dwfl_linux_kernel_find_elf, */
4893 dwfl_standard_find_debuginfo
,
4894 dwfl_offline_section_address
,
4895 (char **) & debuginfo_path
4898 for (std::set
<std::string
>::iterator it
= s
.unwindsym_modules
.begin();
4899 it
!= s
.unwindsym_modules
.end();
4902 string modname
= *it
;
4903 assert (modname
.length() != 0);
4904 if (modname
[0] != '/') continue; // user-space files must be full paths
4905 Dwfl
*dwfl
= dwfl_begin (&user_callbacks
);
4907 throw semantic_error ("cannot create dwfl for " + modname
);
4909 dwfl_report_begin (dwfl
);
4910 Dwfl_Module
* mod
= dwfl_report_offline (dwfl
, modname
.c_str(), modname
.c_str(), -1);
4911 dwfl_report_end (dwfl
, NULL
, NULL
);
4912 if (mod
!= 0) // tolerate missing data; will warn below
4917 if (pending_interrupts
) return;
4918 if (ctx
.undone_unwindsym_modules
.empty()) break;
4919 off
= dwfl_getmodules (dwfl
, &dump_unwindsyms
, (void *) &ctx
, 0);
4922 dwfl_assert("dwfl_getmodules", off
== 0);
4928 // Print out a definition of the runtime's _stp_modules[] globals.
4929 kallsyms_out
<< "\n";
4930 kallsyms_out
<< "static struct _stp_module *_stp_modules [] = {\n";
4931 for (unsigned i
=0; i
<ctx
.stp_module_index
; i
++)
4933 kallsyms_out
<< "& _stp_module_" << i
<< ",\n";
4935 kallsyms_out
<< "};\n";
4936 kallsyms_out
<< "static unsigned _stp_num_modules = " << ctx
.stp_module_index
<< ";\n";
4938 // Some nonexistent modules may have been identified with "-d". Note them.
4939 for (set
<string
>::iterator it
= ctx
.undone_unwindsym_modules
.begin();
4940 it
!= ctx
.undone_unwindsym_modules
.end();
4943 s
.print_warning ("missing unwind/symbol data for module '" + (*it
) + "'");
4949 translate_pass (systemtap_session
& s
)
4953 s
.op
= new translator_output (s
.translated_source
);
4954 c_unparser
cup (& s
);
4959 // This is at the very top of the file.
4961 s
.op
->newline() << "#ifndef MAXNESTING";
4962 s
.op
->newline() << "#define MAXNESTING 10";
4963 s
.op
->newline() << "#endif";
4964 s
.op
->newline() << "#ifndef MAXSTRINGLEN";
4965 s
.op
->newline() << "#define MAXSTRINGLEN 128";
4966 s
.op
->newline() << "#endif";
4967 s
.op
->newline() << "#ifndef MAXACTION";
4968 s
.op
->newline() << "#define MAXACTION 1000";
4969 s
.op
->newline() << "#endif";
4970 s
.op
->newline() << "#ifndef MAXACTION_INTERRUPTIBLE";
4971 s
.op
->newline() << "#define MAXACTION_INTERRUPTIBLE (MAXACTION * 10)";
4972 s
.op
->newline() << "#endif";
4973 s
.op
->newline() << "#ifndef MAXTRYLOCK";
4974 s
.op
->newline() << "#define MAXTRYLOCK MAXACTION";
4975 s
.op
->newline() << "#endif";
4976 s
.op
->newline() << "#ifndef TRYLOCKDELAY";
4977 s
.op
->newline() << "#define TRYLOCKDELAY 100";
4978 s
.op
->newline() << "#endif";
4979 s
.op
->newline() << "#ifndef MAXMAPENTRIES";
4980 s
.op
->newline() << "#define MAXMAPENTRIES 2048";
4981 s
.op
->newline() << "#endif";
4982 s
.op
->newline() << "#ifndef MAXERRORS";
4983 s
.op
->newline() << "#define MAXERRORS 0";
4984 s
.op
->newline() << "#endif";
4985 s
.op
->newline() << "#ifndef MAXSKIPPED";
4986 s
.op
->newline() << "#define MAXSKIPPED 100";
4987 s
.op
->newline() << "#endif";
4988 s
.op
->newline() << "#ifndef MINSTACKSPACE";
4989 s
.op
->newline() << "#define MINSTACKSPACE 1024";
4990 s
.op
->newline() << "#endif";
4991 s
.op
->newline() << "#ifndef INTERRUPTIBLE";
4992 s
.op
->newline() << "#define INTERRUPTIBLE 1";
4993 s
.op
->newline() << "#endif";
4995 // Overload processing
4996 s
.op
->newline() << "#ifndef STP_OVERLOAD_INTERVAL";
4997 s
.op
->newline() << "#define STP_OVERLOAD_INTERVAL 1000000000LL";
4998 s
.op
->newline() << "#endif";
4999 s
.op
->newline() << "#ifndef STP_OVERLOAD_THRESHOLD";
5000 s
.op
->newline() << "#define STP_OVERLOAD_THRESHOLD 500000000LL";
5001 s
.op
->newline() << "#endif";
5002 // We allow the user to completely turn overload processing off
5003 // (as opposed to tuning it by overriding the values above) by
5004 // running: stap -DSTP_NO_OVERLOAD {other options}
5005 s
.op
->newline() << "#ifndef STP_NO_OVERLOAD";
5006 s
.op
->newline() << "#define STP_OVERLOAD";
5007 s
.op
->newline() << "#endif";
5009 s
.op
->newline() << "#define STP_SKIP_BADVARS " << (s
.skip_badvars
? 1 : 0);
5012 s
.op
->newline() << "#define STP_BULKMODE";
5015 s
.op
->newline() << "#define STP_TIMING";
5018 s
.op
->newline() << "#define STP_PERFMON";
5020 s
.op
->newline() << "#include \"runtime.h\"";
5021 s
.op
->newline() << "#include \"stack.c\"";
5022 s
.op
->newline() << "#include \"stat.c\"";
5023 s
.op
->newline() << "#include <linux/string.h>";
5024 s
.op
->newline() << "#include <linux/timer.h>";
5025 s
.op
->newline() << "#include <linux/sched.h>";
5026 s
.op
->newline() << "#include <linux/delay.h>";
5027 s
.op
->newline() << "#include <linux/profile.h>";
5028 s
.op
->newline() << "#include <linux/random.h>";
5029 // s.op->newline() << "#include <linux/utsrelease.h>"; // newer kernels only
5030 s
.op
->newline() << "#include <linux/vermagic.h>";
5031 s
.op
->newline() << "#include <linux/utsname.h>";
5032 s
.op
->newline() << "#include <linux/version.h>";
5033 // s.op->newline() << "#include <linux/compile.h>";
5034 s
.op
->newline() << "#include \"loc2c-runtime.h\" ";
5036 // XXX: old 2.6 kernel hack
5037 s
.op
->newline() << "#ifndef read_trylock";
5038 s
.op
->newline() << "#define read_trylock(x) ({ read_lock(x); 1; })";
5039 s
.op
->newline() << "#endif";
5041 s
.up
->emit_common_header (); // context etc.
5043 for (unsigned i
=0; i
<s
.embeds
.size(); i
++)
5045 s
.op
->newline() << s
.embeds
[i
]->code
<< "\n";
5048 if (s
.globals
.size()>0) {
5049 s
.op
->newline() << "static struct {";
5051 for (unsigned i
=0; i
<s
.globals
.size(); i
++)
5053 s
.up
->emit_global (s
.globals
[i
]);
5055 s
.op
->newline(-1) << "} global = {";
5057 for (unsigned i
=0; i
<s
.globals
.size(); i
++)
5059 if (pending_interrupts
) return 1;
5060 s
.up
->emit_global_init (s
.globals
[i
]);
5062 s
.op
->newline(-1) << "};";
5063 s
.op
->assert_0_indent();
5066 for (map
<string
,functiondecl
*>::iterator it
= s
.functions
.begin(); it
!= s
.functions
.end(); it
++)
5068 if (pending_interrupts
) return 1;
5070 s
.up
->emit_functionsig (it
->second
);
5072 s
.op
->assert_0_indent();
5074 for (map
<string
,functiondecl
*>::iterator it
= s
.functions
.begin(); it
!= s
.functions
.end(); it
++)
5076 if (pending_interrupts
) return 1;
5078 s
.up
->emit_function (it
->second
);
5080 s
.op
->assert_0_indent();
5082 // Run a varuse_collecting_visitor over probes that need global
5083 // variable locks. We'll use this information later in
5084 // emit_locks()/emit_unlocks().
5085 for (unsigned i
=0; i
<s
.probes
.size(); i
++)
5087 if (pending_interrupts
) return 1;
5088 if (s
.probes
[i
]->needs_global_locks())
5089 s
.probes
[i
]->body
->visit (&cup
.vcv_needs_global_locks
);
5091 s
.op
->assert_0_indent();
5093 for (unsigned i
=0; i
<s
.probes
.size(); i
++)
5095 if (pending_interrupts
) return 1;
5096 s
.up
->emit_probe (s
.probes
[i
]);
5098 s
.op
->assert_0_indent();
5101 s
.up
->emit_unprivileged_user_check ();
5102 s
.op
->assert_0_indent();
5104 s
.up
->emit_module_init ();
5105 s
.op
->assert_0_indent();
5107 s
.up
->emit_module_exit ();
5108 s
.op
->assert_0_indent();
5111 // XXX impedance mismatch
5112 s
.op
->newline() << "static int probe_start (void) {";
5113 s
.op
->newline(1) << "return systemtap_module_init () ? -1 : 0;";
5114 s
.op
->newline(-1) << "}";
5116 s
.op
->newline() << "static void probe_exit (void) {";
5117 s
.op
->newline(1) << "systemtap_module_exit ();";
5118 s
.op
->newline(-1) << "}";
5119 s
.op
->assert_0_indent();
5121 for (unsigned i
=0; i
<s
.globals
.size(); i
++)
5124 s
.up
->emit_global_param (s
.globals
[i
]);
5126 s
.op
->assert_0_indent();
5128 emit_symbol_data (s
);
5130 s
.op
->newline() << "MODULE_DESCRIPTION(\"systemtap-generated probe\");";
5131 s
.op
->newline() << "MODULE_LICENSE(\"GPL\");";
5132 s
.op
->assert_0_indent();
5134 catch (const semantic_error
& e
)
5139 s
.op
->line() << "\n";
5145 return rc
+ s
.num_errors();
5148 /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */