From 4d0266a0e0d9e9b615b04ff209a73d3725495835 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Tue, 3 Apr 2018 18:23:30 -0600 Subject: [PATCH] Change value history to use value_ref_ptr This simplifies the value history implementation by replacing the current data structure with a std::vector, and by making the value history simply hold a reference to each value. gdb/ChangeLog 2018-04-06 Tom Tromey * value.c (VALUE_HISTORY_CHUNK, struct value_history_chunk) (value_history_chain, value_history_count): Remove. (value_history): New global. (record_latest_value, access_value_history, show_values) (preserve_values): Update. --- gdb/ChangeLog | 8 +++++++ gdb/value.c | 66 ++++++++++----------------------------------------- 2 files changed, 20 insertions(+), 54 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 97b3cfa929c..67d87af1330 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,11 @@ +2018-04-06 Tom Tromey + + * value.c (VALUE_HISTORY_CHUNK, struct value_history_chunk) + (value_history_chain, value_history_count): Remove. + (value_history): New global. + (record_latest_value, access_value_history, show_values) + (preserve_values): Update. + 2018-04-06 Tom Tromey * varobj.h (struct varobj) : Now a value_ref_ptr. diff --git a/gdb/value.c b/gdb/value.c index 013fcfe3ed0..677ec42e636 100644 --- a/gdb/value.c +++ b/gdb/value.c @@ -881,25 +881,10 @@ value_contents_eq (const struct value *val1, LONGEST offset1, } -/* The value-history records all the values printed - by print commands during this session. Each chunk - records 60 consecutive values. The first chunk on - the chain records the most recent values. - The total number of values is in value_history_count. */ +/* The value-history records all the values printed by print commands + during this session. */ -#define VALUE_HISTORY_CHUNK 60 - -struct value_history_chunk - { - struct value_history_chunk *next; - struct value *values[VALUE_HISTORY_CHUNK]; - }; - -/* Chain of chunks now in use. */ - -static struct value_history_chunk *value_history_chain; - -static int value_history_count; /* Abs number of last entry stored. */ +static std::vector value_history; /* List of all value objects currently allocated @@ -1898,24 +1883,9 @@ record_latest_value (struct value *val) but the current contents of that location. c'est la vie... */ val->modifiable = 0; - /* Here we treat value_history_count as origin-zero - and applying to the value being stored now. */ - - i = value_history_count % VALUE_HISTORY_CHUNK; - if (i == 0) - { - struct value_history_chunk *newobj = XCNEW (struct value_history_chunk); + value_history.push_back (release_value (val)); - newobj->next = value_history_chain; - value_history_chain = newobj; - } - - value_history_chain->values[i] = release_value (val).release (); - - /* Now we regard value_history_count as origin-one - and applying to the value just stored. */ - - return ++value_history_count; + return value_history.size (); } /* Return a copy of the value in the history with sequence number NUM. */ @@ -1923,12 +1893,11 @@ record_latest_value (struct value *val) struct value * access_value_history (int num) { - struct value_history_chunk *chunk; int i; int absnum = num; if (absnum <= 0) - absnum += value_history_count; + absnum += value_history.size (); if (absnum <= 0) { @@ -1939,20 +1908,12 @@ access_value_history (int num) else error (_("History does not go back to $$%d."), -num); } - if (absnum > value_history_count) + if (absnum > value_history.size ()) error (_("History has not yet reached $%d."), absnum); absnum--; - /* Now absnum is always absolute and origin zero. */ - - chunk = value_history_chain; - for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK - - absnum / VALUE_HISTORY_CHUNK; - i > 0; i--) - chunk = chunk->next; - - return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK]); + return value_copy (value_history[absnum].get ()); } static void @@ -1972,13 +1933,13 @@ show_values (const char *num_exp, int from_tty) else { /* "show values" means print the last 10 values. */ - num = value_history_count - 9; + num = value_history.size () - 9; } if (num <= 0) num = 1; - for (i = num; i < num + 10 && i <= value_history_count; i++) + for (i = num; i < num + 10 && i <= value_history.size (); i++) { struct value_print_options opts; @@ -2626,7 +2587,6 @@ void preserve_values (struct objfile *objfile) { htab_t copied_types; - struct value_history_chunk *cur; struct internalvar *var; int i; @@ -2634,10 +2594,8 @@ preserve_values (struct objfile *objfile) it is soon to be deleted. */ copied_types = create_copied_types_hash (objfile); - for (cur = value_history_chain; cur; cur = cur->next) - for (i = 0; i < VALUE_HISTORY_CHUNK; i++) - if (cur->values[i]) - preserve_one_value (cur->values[i], objfile, copied_types); + for (const value_ref_ptr &item : value_history) + preserve_one_value (item.get (), objfile, copied_types); for (var = internalvars; var; var = var->next) preserve_one_internalvar (var, objfile, copied_types); -- 2.30.2