[committed] analyzer: don't track string literals in the store [PR106359]

[David Malcolm via Gcc-patches]

Doing so speeds up -fanalyzer from taking over 4 hours to under a
minute on the Linux kernel's sound/soc/codecs/cs47l90.c

Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
Pushed to trunk as r13-1761-g68871a008e686d.

gcc/analyzer/ChangeLog:
        PR analyzer/106359
        * region.h (string_region::tracked_p): New.
        * store.cc (binding_cluster::binding_cluster): Move here from
        store.h.  Add assertion that base_region is tracked_p.
        * store.h (binding_cluster::binding_cluster): Move to store.cc.

Signed-off-by: David Malcolm <dmalc...@redhat.com>
---
 gcc/analyzer/region.h | 4 ++++
 gcc/analyzer/store.cc | 7 +++++++
 gcc/analyzer/store.h  | 4 +---
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/gcc/analyzer/region.h b/gcc/analyzer/region.h
index 60d8149f513..fd0d4a05cc9 100644
--- a/gcc/analyzer/region.h
+++ b/gcc/analyzer/region.h
@@ -1151,6 +1151,10 @@ public:
 
   void dump_to_pp (pretty_printer *pp, bool simple) const final override;
 
+  /* We assume string literals are immutable, so we don't track them in
+     the store.  */
+  bool tracked_p () const final override { return false; }
+
   tree get_string_cst () const { return m_string_cst; }
 
 private:
diff --git a/gcc/analyzer/store.cc b/gcc/analyzer/store.cc
index 06151d8c041..e3dabf300df 100644
--- a/gcc/analyzer/store.cc
+++ b/gcc/analyzer/store.cc
@@ -1103,6 +1103,13 @@ binding_map::remove_overlapping_bindings (store_manager 
*mgr,
 
 /* class binding_cluster.  */
 
+binding_cluster::binding_cluster (const region *base_region)
+: m_base_region (base_region), m_map (),
+  m_escaped (false), m_touched (false)
+{
+  gcc_assert (base_region->tracked_p ());
+}
+
 /* binding_cluster's copy ctor.  */
 
 binding_cluster::binding_cluster (const binding_cluster &other)
diff --git a/gcc/analyzer/store.h b/gcc/analyzer/store.h
index 368b2990ae8..9b54c7b9156 100644
--- a/gcc/analyzer/store.h
+++ b/gcc/analyzer/store.h
@@ -544,9 +544,7 @@ public:
   typedef hash_map <const binding_key *, const svalue *> map_t;
   typedef map_t::iterator iterator_t;
 
-  binding_cluster (const region *base_region)
-  : m_base_region (base_region), m_map (),
-    m_escaped (false), m_touched (false) {}
+  binding_cluster (const region *base_region);
   binding_cluster (const binding_cluster &other);
   binding_cluster& operator=(const binding_cluster &other);
 
-- 
2.26.3