Re: [RFA]: Handle multi-line versions of multi-breakpoints

[Doug Evans <dje at google dot com>]

Ping.

On Sat, Mar 28, 2009 at 9:21 PM, Doug Evans <dje@google.com> wrote:
> Ping.
> [This doesn't seem to be a controversial patch, and there is
> definitely a bug here that needs fixing.]
>
> On Fri, Mar 13, 2009 at 9:47 AM, Doug Evans <dje@google.com> wrote:
>> Ping.
>>
>> On Sun, Mar 1, 2009 at 11:53 PM, Doug Evans <dje@google.com> wrote:
>>> Hi.
>>>
>>> "multi-breakpoints" (multiple breakpoints for the same source line)
>>> don't work for constructors and inline functions where the source expression
>>> spans several lines (at least for the new testcases included in this patch).
>>>
>>> This patch fixes it by, if there's no exact match,
>>> rescanning the symtabs for all matches of the best match.
>>> Included are updated testcases to exercise the bug.
>>> The bug isn't exposed by templates, but I updated mb-templates.{cc,exp}
>>> anyway (if only to confirm things work there too).
>>>
>>> Ok to check in?
>>>
>>> 2009-03-01 ?Doug Evans ?<dje@google.com>
>>>
>>> ? ? ? ?* symtab.c (expand_line_sal): If we don't find an exact match,
>>> ? ? ? ?rescan all symtabs again to find all copies of the best match.
>>>
>>> ? ? ? ?* gdb.cp/mb-ctor.exp: Add multi-line source statement test.
>>> ? ? ? ?* gdb.cp/mb-ctor.cc: Ditto.
>>> ? ? ? ?* gdb.cp/mb-inline.exp: Add multi-line source statement test.
>>> ? ? ? ?* gdb.cp/mb-inline.h (multi_line_foo): New function.
>>> ? ? ? ?* gdb.cp/mb-inline1.cc: Call it.
>>> ? ? ? ?* gdb.cp/mb-inline2.cc: Ditto.
>>> ? ? ? ?* gdb.cp/mb-templates.exp: Add multi-line source statement test.
>>> ? ? ? ?* gdb.cp/mb-templates.cc (multi_line_foo): New template.
>>>
>>> Index: symtab.c
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/symtab.c,v
>>> retrieving revision 1.204
>>> diff -u -p -r1.204 symtab.c
>>> --- symtab.c ? ?2 Mar 2009 06:33:24 -0000 ? ? ? 1.204
>>> +++ symtab.c ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -4481,7 +4481,6 @@ expand_line_sal (struct symtab_and_line
>>> ? else
>>> ? ? {
>>> ? ? ? struct linetable_entry *best_item = 0;
>>> - ? ? ?struct symtab *best_symtab = 0;
>>> ? ? ? int exact = 0;
>>>
>>> ? ? ? lineno = sal.line;
>>> @@ -4533,13 +4532,41 @@ expand_line_sal (struct symtab_and_line
>>> ? ? ? ? ? ? ? ? ? ? ? ? ? && (best_item == NULL || item->line < best_item->line))
>>> ? ? ? ? ? ? ? ? ? ?{
>>> ? ? ? ? ? ? ? ? ? ? ?best_item = item;
>>> - ? ? ? ? ? ? ? ? ? ? best_symtab = symtab;
>>> ? ? ? ? ? ? ? ? ? ?}
>>> ? ? ? ? ? ? ? ?}
>>> ? ? ? ? ? ?}
>>> ? ? ? ?}
>>> +
>>> ? ? ? if (!exact && best_item)
>>> - ? ? ? append_expanded_sal (&ret, best_symtab, lineno, best_item->pc);
>>> + ? ? ? {
>>> + ? ? ? ? /* We found a "good enough" match.
>>> + ? ? ? ? ? ?Rescan to find all such matches.
>>> + ? ? ? ? ? ?This is to handle constructors, templates, inline-functions
>>> + ? ? ? ? ? ?that have multiple breakpoints for one line number. ?*/
>>> +
>>> + ? ? ? ? ALL_SYMTABS (objfile, symtab)
>>> + ? ? ? ? ? {
>>> + ? ? ? ? ? ? if (strcmp (sal.symtab->filename,
>>> + ? ? ? ? ? ? ? ? ? ? ? ? symtab->filename) == 0)
>>> + ? ? ? ? ? ? ? {
>>> + ? ? ? ? ? ? ? ? struct linetable *l;
>>> + ? ? ? ? ? ? ? ? int len;
>>> + ? ? ? ? ? ? ? ? l = LINETABLE (symtab);
>>> + ? ? ? ? ? ? ? ? if (!l)
>>> + ? ? ? ? ? ? ? ? ? continue;
>>> + ? ? ? ? ? ? ? ? len = l->nitems;
>>> +
>>> + ? ? ? ? ? ? ? ? for (j = 0; j < len; j++)
>>> + ? ? ? ? ? ? ? ? ? {
>>> + ? ? ? ? ? ? ? ? ? ? struct linetable_entry *item = &(l->item[j]);
>>> +
>>> + ? ? ? ? ? ? ? ? ? ? if (item->line == best_item->line)
>>> + ? ? ? ? ? ? ? ? ? ? ? append_expanded_sal (&ret, symtab, item->line,
>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?item->pc);
>>> + ? ? ? ? ? ? ? ? ? }
>>> + ? ? ? ? ? ? ? }
>>> + ? ? ? ? ? }
>>> + ? ? ? }
>>> ? ? }
>>>
>>> ? /* For optimized code, compiler can scatter one source line accross
>>> Index: testsuite/gdb.cp/mb-ctor.cc
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-ctor.cc,v
>>> retrieving revision 1.1
>>> diff -u -p -r1.1 mb-ctor.cc
>>> --- testsuite/gdb.cp/mb-ctor.cc 24 Sep 2007 07:40:32 -0000 ? ? ?1.1
>>> +++ testsuite/gdb.cp/mb-ctor.cc 2 Mar 2009 06:39:17 -0000
>>> @@ -28,11 +28,19 @@ public:
>>> ? ~Derived();
>>> ?private:
>>> ? int i;
>>> + ?int i2;
>>> ?};
>>>
>>> ?Derived::Derived(int i) : Base(i)
>>> ?{
>>> ? this->i = i;
>>> + ?/* The next statement is spread over two lines on purpose to exercise
>>> + ? ? a bug where breakpoints set on all but the last line of a statement
>>> + ? ? would not get multiple breakpoints.
>>> + ? ? The second line's text for gdb_get_line_number is a subset of the
>>> + ? ? first line so that we don't care which line gdb prints when it stops. ?*/
>>> + ?this->i2 = // set breakpoint here
>>> + ? ?i; // breakpoint here
>>> ?}
>>>
>>> ?Derived::~Derived()
>>> Index: testsuite/gdb.cp/mb-ctor.exp
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-ctor.exp,v
>>> retrieving revision 1.5
>>> diff -u -p -r1.5 mb-ctor.exp
>>> --- testsuite/gdb.cp/mb-ctor.exp ? ? ? ?3 Jan 2009 05:58:04 -0000 ? ? ? 1.5
>>> +++ testsuite/gdb.cp/mb-ctor.exp ? ? ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -43,6 +43,11 @@ gdb_start
>>> ?gdb_reinitialize_dir $srcdir/$subdir
>>> ?gdb_load ${binfile}
>>>
>>> +if ![runto_main] then {
>>> + ? ?perror "couldn't run to breakpoint"
>>> + ? ?continue
>>> +}
>>> +
>>> ?# Set a breakpoint with multiple locations
>>> ?# and a condition.
>>>
>>> @@ -50,34 +55,31 @@ gdb_test "break 'Derived::Derived(int)'"
>>> ? ? "Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
>>> ? ? "set-breakpoint at ctor"
>>>
>>> +gdb_breakpoint [gdb_get_line_number "set breakpoint here"]
>>> +
>>> ?gdb_test "break 'Derived::~Derived()'" \
>>> ? ? "Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
>>> ? ? "set-breakpoint at dtor"
>>>
>>> -gdb_run_cmd
>>> -gdb_expect {
>>> - ? ?-re "Breakpoint \[0-9\]+,.*Derived.*i=7.*$gdb_prompt $" {
>>> - ? ? ? pass "run to breakpoint"
>>> - ? ?}
>>> - ? ?-re "$gdb_prompt $" {
>>> - ? ? ? fail "run to breakpoint"
>>> - ? ?}
>>> - ? ?timeout {
>>> - ? ? ? fail "run to breakpoint (timeout)"
>>> - ? ?}
>>> -}
>>> +gdb_test "continue" \
>>> + ? ?".*Breakpoint.*Derived.*i=7.*" \
>>> + ? ?"run to breakpoint 1 v1"
>>> +
>>> +gdb_continue_to_breakpoint "set breakpoint here" ".* breakpoint here"
>>>
>>> ?gdb_test "continue" \
>>> ? ? ".*Breakpoint.*Derived.*i=15.*" \
>>> - ? ?"run to breakpoint 2"
>>> + ? ?"run to breakpoint 1 v2"
>>> +
>>> +gdb_continue_to_breakpoint "set breakpoint here" ".* breakpoint here"
>>>
>>> ?gdb_test "continue" \
>>> ? ? ".*Breakpoint.*~Derived.*" \
>>> - ? ?"run to breakpoint 3"
>>> + ? ?"run to breakpoint 3 v1"
>>>
>>> ?gdb_test "continue" \
>>> ? ? ".*Breakpoint.*~Derived.*" \
>>> - ? ?"run to breakpoint 4"
>>> + ? ?"run to breakpoint 3 v2"
>>>
>>> ?gdb_test "continue" \
>>> ? ? ".*exited normally.*" \
>>> Index: testsuite/gdb.cp/mb-inline.exp
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline.exp,v
>>> retrieving revision 1.2
>>> diff -u -p -r1.2 mb-inline.exp
>>> --- testsuite/gdb.cp/mb-inline.exp ? ? ?3 Jan 2009 05:58:04 -0000 ? ? ? 1.2
>>> +++ testsuite/gdb.cp/mb-inline.exp ? ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -106,3 +106,25 @@ gdb_expect {
>>> ?gdb_test "continue" \
>>> ? ? ".*Program exited normally.*" \
>>> ? ? "continue with disabled breakpoint 1.2"
>>> +
>>> +# Make sure we can set a breakpoint on a source statement that spans
>>> +# multiple lines.
>>> +
>>> +delete_breakpoints
>>> +
>>> +set bp_location [gdb_get_line_number "set multi-line breakpoint here" $hdrfile]
>>> +
>>> +if { ![runto_main] } {
>>> + ? ?fail "Can't run to main for multi_line_foo tests."
>>> + ? ?return 0
>>> +}
>>> +
>>> +gdb_test "break $hdrfile:$bp_location" \
>>> + ? ?"Breakpoint.*at.* file .*$hdrfile, line.*\\(2 locations\\).*" \
>>> + ? ?"set multi_line_foo breakpoint"
>>> +gdb_test "continue" \
>>> + ? ?".*Breakpoint.*multi_line_foo \\(i=0\\).*" \
>>> + ? ?"run to multi_line_foo breakpoint 4 afn"
>>> +gdb_test "continue" \
>>> + ? ?".*Breakpoint.*multi_line_foo \\(i=1\\).*" \
>>> + ? ?"run to multi_line_foo breakpoint 4 bfn"
>>> Index: testsuite/gdb.cp/mb-inline.h
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline.h,v
>>> retrieving revision 1.2
>>> diff -u -p -r1.2 mb-inline.h
>>> --- testsuite/gdb.cp/mb-inline.h ? ? ? ?3 Jan 2009 05:58:04 -0000 ? ? ? 1.2
>>> +++ testsuite/gdb.cp/mb-inline.h ? ? ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -26,5 +26,12 @@ foo (int i)
>>> ? return i; // set breakpoint here
>>> ?}
>>>
>>> +static int
>>> +multi_line_foo (int i)
>>> +{
>>> + ?return // set multi-line breakpoint here
>>> + ? ?i;
>>> +}
>>> +
>>> ?extern int afn ();
>>> ?extern int bfn ();
>>> Index: testsuite/gdb.cp/mb-inline1.cc
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline1.cc,v
>>> retrieving revision 1.2
>>> diff -u -p -r1.2 mb-inline1.cc
>>> --- testsuite/gdb.cp/mb-inline1.cc ? ? ?3 Jan 2009 05:58:04 -0000 ? ? ? 1.2
>>> +++ testsuite/gdb.cp/mb-inline1.cc ? ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -23,7 +23,7 @@
>>> ?int
>>> ?afn ()
>>> ?{
>>> - ?return foo (0);
>>> + ?return foo (0) + multi_line_foo (0);
>>> ?}
>>>
>>> ?int
>>> Index: testsuite/gdb.cp/mb-inline2.cc
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-inline2.cc,v
>>> retrieving revision 1.2
>>> diff -u -p -r1.2 mb-inline2.cc
>>> --- testsuite/gdb.cp/mb-inline2.cc ? ? ?3 Jan 2009 05:58:04 -0000 ? ? ? 1.2
>>> +++ testsuite/gdb.cp/mb-inline2.cc ? ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -21,5 +21,5 @@
>>> ?int
>>> ?bfn ()
>>> ?{
>>> - ?return foo (1);
>>> + ?return foo (1) + multi_line_foo (1);
>>> ?}
>>> Index: testsuite/gdb.cp/mb-templates.cc
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-templates.cc,v
>>> retrieving revision 1.1
>>> diff -u -p -r1.1 mb-templates.cc
>>> --- testsuite/gdb.cp/mb-templates.cc ? ?24 Sep 2007 07:40:32 -0000 ? ? ?1.1
>>> +++ testsuite/gdb.cp/mb-templates.cc ? ?2 Mar 2009 06:39:17 -0000
>>> @@ -8,6 +8,13 @@ void foo(T i)
>>> ? std::cout << "hi\n"; // set breakpoint here
>>> ?}
>>>
>>> +template<class T>
>>> +void multi_line_foo(T i)
>>> +{
>>> + ?std::cout // set multi-line breakpoint here
>>> + ? ?<< "hi\n";
>>> +}
>>> +
>>> ?int main()
>>> ?{
>>> ? ? foo<int>(0);
>>> @@ -16,4 +23,9 @@ int main()
>>> ? ? foo<double>(1);
>>> ? ? foo<int>(2);
>>> ? ? foo<double>(2);
>>> +
>>> + ? ?multi_line_foo<int>(0);
>>> + ? ?multi_line_foo<double>(0);
>>> +
>>> + ? ?return 0;
>>> ?}
>>> Index: testsuite/gdb.cp/mb-templates.exp
>>> ===================================================================
>>> RCS file: /cvs/src/src/gdb/testsuite/gdb.cp/mb-templates.exp,v
>>> retrieving revision 1.5
>>> diff -u -p -r1.5 mb-templates.exp
>>> --- testsuite/gdb.cp/mb-templates.exp ? 3 Jan 2009 05:58:04 -0000 ? ? ? 1.5
>>> +++ testsuite/gdb.cp/mb-templates.exp ? 2 Mar 2009 06:39:17 -0000
>>> @@ -165,3 +165,25 @@ gdb_test "continue" \
>>> ? ? ".*Breakpoint.*foo<int> \\(i=1\\).*" \
>>> ? ? "instantiation: run to breakpoint 2"
>>>
>>> +
>>> +# Make sure we can set a breakpoint on a source statement that spans
>>> +# multiple lines.
>>> +
>>> +delete_breakpoints
>>> +
>>> +set bp_location [gdb_get_line_number "set multi-line breakpoint here"]
>>> +
>>> +if { ![runto_main] } {
>>> + ? ?fail "Can't run to main for multi_line_foo tests."
>>> + ? ?return 0
>>> +}
>>> +
>>> +gdb_test "break $srcfile:$bp_location" \
>>> + ? ?"Breakpoint.*at.* file .*$srcfile, line.*\\(2 locations\\).*" \
>>> + ? ?"set multi_line_foo breakpoint"
>>> +gdb_test "continue" \
>>> + ? ?".*Breakpoint.*multi_line_foo<int> \\(i=0\\).*" \
>>> + ? ?"run to multi_line_foo breakpoint 2 <int>"
>>> +gdb_test "continue" \
>>> + ? ?".*Breakpoint.*multi_line_foo<double> \\(i=0\\).*" \
>>> + ? ?"run to multi_line_foo breakpoint 2 <double>"
>>>
>>
>