From 828d3400fb1a9914ab16ee05dfe2647af8c566c5 Mon Sep 17 00:00:00 2001 From: Daniel Jacobowitz Date: Tue, 21 Jul 2009 18:12:40 +0000 Subject: [PATCH] gdb/ * value.c (struct value): Add reference_count field. (allocate_value_lazy): Initialize reference_count. (value_incref): New function. (value_free): Check the reference count. * value.h (value_incref): New prototype. --- gdb/ChangeLog | 8 ++++++++ gdb/value.c | 29 +++++++++++++++++++++++++++++ gdb/value.h | 2 ++ 3 files changed, 39 insertions(+) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index de19c96c78c..37555d13574 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,11 @@ +2009-07-21 Daniel Jacobowitz + + * value.c (struct value): Add reference_count field. + (allocate_value_lazy): Initialize reference_count. + (value_incref): New function. + (value_free): Check the reference count. + * value.h (value_incref): New prototype. + 2009-07-20 Marc Khouzam * utils.c (defaulted_query): Update comment and remove dead code. diff --git a/gdb/value.c b/gdb/value.c index fffc183af07..904bd5ea9e8 100644 --- a/gdb/value.c +++ b/gdb/value.c @@ -194,6 +194,13 @@ struct value /* Actual contents of the value. Target byte-order. NULL or not valid if lazy is nonzero. */ gdb_byte *contents; + + /* The number of references to this value. When a value is created, + the value chain holds a reference, so REFERENCE_COUNT is 1. If + release_value is called, this value is removed from the chain but + the caller of release_value now has a reference to this value. + The caller must arrange for a call to value_free later. */ + int reference_count; }; /* Prototypes for local functions. */ @@ -259,6 +266,10 @@ allocate_value_lazy (struct type *type) val->pointed_to_offset = 0; val->modifiable = 1; val->initialized = 1; /* Default to initialized. */ + + /* Values start out on the all_values chain. */ + val->reference_count = 1; + return val; } @@ -583,11 +594,29 @@ value_mark (void) return all_values; } +/* Take a reference to VAL. VAL will not be deallocated until all + references are released. */ + +void +value_incref (struct value *val) +{ + val->reference_count++; +} + +/* Release a reference to VAL, which was acquired with value_incref. + This function is also called to deallocate values from the value + chain. */ + void value_free (struct value *val) { if (val) { + gdb_assert (val->reference_count > 0); + val->reference_count--; + if (val->reference_count > 0) + return; + if (VALUE_LVAL (val) == lval_computed) { struct lval_funcs *funcs = val->location.computed.funcs; diff --git a/gdb/value.h b/gdb/value.h index d8161565811..039e160bfe7 100644 --- a/gdb/value.h +++ b/gdb/value.h @@ -582,6 +582,8 @@ extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1); extern int destructor_name_p (const char *name, const struct type *type); +extern void value_incref (struct value *val); + extern void value_free (struct value *val); extern void free_all_values (void); -- 2.30.2