diff options
Diffstat (limited to 'gcc/analyzer')
| -rw-r--r-- | gcc/analyzer/region-model.cc | 82 | ||||
| -rw-r--r-- | gcc/analyzer/region-model.h | 6 | ||||
| -rw-r--r-- | gcc/analyzer/region.cc | 57 | ||||
| -rw-r--r-- | gcc/analyzer/store.cc | 12 | ||||
| -rw-r--r-- | gcc/analyzer/store.h | 2 |
5 files changed, 130 insertions, 29 deletions
diff --git a/gcc/analyzer/region-model.cc b/gcc/analyzer/region-model.cc index c3d9ca7..5b08e48 100644 --- a/gcc/analyzer/region-model.cc +++ b/gcc/analyzer/region-model.cc @@ -1204,6 +1204,76 @@ region_model::get_rvalue (tree expr, region_model_context *ctxt) return get_rvalue (path_var (expr, get_stack_depth () - 1), ctxt); } +/* Return true if this model is on a path with "main" as the entrypoint + (as opposed to one in which we're merely analyzing a subset of the + path through the code). */ + +bool +region_model::called_from_main_p () const +{ + if (!m_current_frame) + return false; + /* Determine if the oldest stack frame in this model is for "main". */ + const frame_region *frame0 = get_frame_at_index (0); + gcc_assert (frame0); + return id_equal (DECL_NAME (frame0->get_function ()->decl), "main"); +} + +/* Subroutine of region_model::get_store_value for when REG is (or is within) + a global variable that hasn't been touched since the start of this path + (or was implicitly touched due to a call to an unknown function). */ + +const svalue * +region_model::get_initial_value_for_global (const region *reg) const +{ + /* Get the decl that REG is for (or is within). */ + const decl_region *base_reg + = reg->get_base_region ()->dyn_cast_decl_region (); + gcc_assert (base_reg); + tree decl = base_reg->get_decl (); + + /* Special-case: to avoid having to explicitly update all previously + untracked globals when calling an unknown fn, they implicitly have + an unknown value if an unknown call has occurred, unless this is + static to-this-TU and hasn't escaped. Globals that have escaped + are explicitly tracked, so we shouldn't hit this case for them. */ + if (m_store.called_unknown_fn_p () && TREE_PUBLIC (decl)) + return m_mgr->get_or_create_unknown_svalue (reg->get_type ()); + + /* If we are on a path from the entrypoint from "main" and we have a + global decl defined in this TU that hasn't been touched yet, then + the initial value of REG can be taken from the initialization value + of the decl. */ + if (called_from_main_p () && !DECL_EXTERNAL (decl)) + { + /* Get the initializer value for base_reg. */ + const svalue *base_reg_init + = base_reg->get_svalue_for_initializer (m_mgr); + gcc_assert (base_reg_init); + if (reg == base_reg) + return base_reg_init; + else + { + /* Get the value for REG within base_reg_init. */ + binding_cluster c (base_reg); + c.bind (m_mgr->get_store_manager (), base_reg, base_reg_init, + BK_direct); + const svalue *sval + = c.get_any_binding (m_mgr->get_store_manager (), reg); + if (sval) + { + if (reg->get_type ()) + sval = m_mgr->get_or_create_cast (reg->get_type (), + sval); + return sval; + } + } + } + + /* Otherwise, return INIT_VAL(REG). */ + return m_mgr->get_or_create_initial_value (reg); +} + /* Get a value for REG, looking it up in the store, or otherwise falling back to "initial" or "unknown" values. */ @@ -1256,14 +1326,10 @@ region_model::get_store_value (const region *reg) const would have returned UNKNOWN, and we would already have returned that above). */ - /* Special-case: to avoid having to explicitly update all previously - untracked globals when calling an unknown fn, we instead change - the default here so we implicitly have an unknown value for such - regions. */ - if (m_store.called_unknown_fn_p ()) - if (reg->get_base_region ()->get_parent_region ()->get_kind () - == RK_GLOBALS) - return m_mgr->get_or_create_unknown_svalue (reg->get_type ()); + /* Handle globals. */ + if (reg->get_base_region ()->get_parent_region ()->get_kind () + == RK_GLOBALS) + return get_initial_value_for_global (reg); return m_mgr->get_or_create_initial_value (reg); } diff --git a/gcc/analyzer/region-model.h b/gcc/analyzer/region-model.h index 3d044bf..79d739e 100644 --- a/gcc/analyzer/region-model.h +++ b/gcc/analyzer/region-model.h @@ -1870,6 +1870,9 @@ public: int get_stack_depth () const; const svalue *maybe_get_constant_value (region_model_manager *mgr) const; + const svalue *get_svalue_for_constructor (tree ctor, + region_model_manager *mgr) const; + const svalue *get_svalue_for_initializer (region_model_manager *mgr) const; private: tree m_decl; @@ -2701,6 +2704,9 @@ class region_model void record_dynamic_extents (const region *reg, const svalue *size_in_bytes); + bool called_from_main_p () const; + const svalue *get_initial_value_for_global (const region *reg) const; + /* Storing this here to avoid passing it around everywhere. */ region_model_manager *const m_mgr; diff --git a/gcc/analyzer/region.cc b/gcc/analyzer/region.cc index 770e2cb..c3dc8cd 100644 --- a/gcc/analyzer/region.cc +++ b/gcc/analyzer/region.cc @@ -886,20 +886,53 @@ decl_region::maybe_get_constant_value (region_model_manager *mgr) const && DECL_IN_CONSTANT_POOL (m_decl) && DECL_INITIAL (m_decl) && TREE_CODE (DECL_INITIAL (m_decl)) == CONSTRUCTOR) - { - tree ctor = DECL_INITIAL (m_decl); - gcc_assert (!TREE_CLOBBER_P (ctor)); + return get_svalue_for_constructor (DECL_INITIAL (m_decl), mgr); + return NULL; +} - /* Create a binding map, applying ctor to it, using this - decl_region as the base region when building child regions - for offset calculations. */ - binding_map map; - map.apply_ctor_to_region (this, ctor, mgr); +/* Get an svalue for CTOR, a CONSTRUCTOR for this region's decl. */ - /* Return a compound svalue for the map we built. */ - return mgr->get_or_create_compound_svalue (get_type (), map); - } - return NULL; +const svalue * +decl_region::get_svalue_for_constructor (tree ctor, + region_model_manager *mgr) const +{ + gcc_assert (!TREE_CLOBBER_P (ctor)); + + /* Create a binding map, applying ctor to it, using this + decl_region as the base region when building child regions + for offset calculations. */ + binding_map map; + map.apply_ctor_to_region (this, ctor, mgr); + + /* Return a compound svalue for the map we built. */ + return mgr->get_or_create_compound_svalue (get_type (), map); +} + +/* For use on decl_regions for global variables. + + Get an svalue for the initial value of this region at entry to + "main" (either based on DECL_INITIAL, or implicit initialization to + zero. */ + +const svalue * +decl_region::get_svalue_for_initializer (region_model_manager *mgr) const +{ + tree init = DECL_INITIAL (m_decl); + if (!init) + { + /* Implicit initialization to zero; use a compound_svalue for it. */ + binding_cluster c (this); + c.zero_fill_region (mgr->get_store_manager (), this); + return mgr->get_or_create_compound_svalue (TREE_TYPE (m_decl), + c.get_map ()); + } + + if (TREE_CODE (init) == CONSTRUCTOR) + return get_svalue_for_constructor (init, mgr); + + /* Reuse the get_rvalue logic from region_model. */ + region_model m (mgr); + return m.get_rvalue (path_var (init, 0), NULL); } /* class field_region : public region. */ diff --git a/gcc/analyzer/store.cc b/gcc/analyzer/store.cc index 5af86d0..d854f4e 100644 --- a/gcc/analyzer/store.cc +++ b/gcc/analyzer/store.cc @@ -396,15 +396,9 @@ get_subregion_within_ctor (const region *parent_reg, tree index, static const svalue * get_svalue_for_ctor_val (tree val, region_model_manager *mgr) { - if (TREE_CODE (val) == ADDR_EXPR) - { - gcc_assert (TREE_CODE (TREE_OPERAND (val, 0)) == STRING_CST); - const string_region *str_reg - = mgr->get_region_for_string (TREE_OPERAND (val, 0)); - return mgr->get_ptr_svalue (TREE_TYPE (val), str_reg); - } - gcc_assert (CONSTANT_CLASS_P (val)); - return mgr->get_or_create_constant_svalue (val); + /* Reuse the get_rvalue logic from region_model. */ + region_model m (mgr); + return m.get_rvalue (path_var (val, 0), NULL); } /* Bind values from CONSTRUCTOR to this map, relative to diff --git a/gcc/analyzer/store.h b/gcc/analyzer/store.h index 16bad03..bc9dc2e 100644 --- a/gcc/analyzer/store.h +++ b/gcc/analyzer/store.h @@ -451,6 +451,8 @@ public: iterator_t begin () const { return m_map.begin (); } iterator_t end () const { return m_map.end (); } + const binding_map &get_map () const { return m_map; } + private: const svalue *get_any_value (const binding_key *key) const; void get_overlapping_bindings (store_manager *mgr, const region *reg, |