analyzer: start adding support for errno

gcc/analyzer/ChangeLog:
	* region-model-impl-calls.cc
	(region_model::impl_call_errno_location): New.
	* region-model-manager.cc
	(region_model_manager::region_model_manager): Initialize
	m_thread_local_region and m_errno_region.
	* region-model-manager.h (region_model_manager::get_errno_region):
	New accessor.
	(region_model_manager::m_thread_local_region): New.
	(region_model_manager::m_errno_region): New.
	* region-model.cc (region_model::on_call_pre): Special-case
	"__errno_location".
	(region_model::set_errno): New.
	* region-model.h (impl_call_errno_location): New decl.
	(region_model::set_errno): New decl.
	* region.cc (thread_local_region::dump_to_pp): New.
	(errno_region::dump_to_pp): New.
	* region.h (enum memory_space): Add MEMSPACE_THREAD_LOCAL.
	(enum region_kind): Add RK_THREAD_LOCAL and RK_ERRNO.
	(class thread_local_region): New.
	(is_a_helper <const thread_local_region *>::test): New.
	(class errno_region): New.
	(is_a_helper <const errno_region *>::test): New.
	* store.cc (binding_cluster::escaped_p): New.
	(store::escaped_p): Treat errno as always having escaped.
	(store::replay_call_summary_cluster): Handle RK_THREAD_LOCAL and
	RK_ERRNO.
	* store.h (binding_cluster::escaped_p): Remove definition.

gcc/testsuite/ChangeLog:
	* gcc.dg/analyzer/errno-1.c: New test.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

1 files changed, 59 insertions, 1 deletions

diff --git a/gcc/analyzer/region.h b/gcc/analyzer/region.h
index 6315fac..ecae887 100644
--- a/gcc/analyzer/region.h
+++ b/gcc/analyzer/region.h
@@ -34,7 +34,8 @@ enum memory_space
   MEMSPACE_GLOBALS,
   MEMSPACE_STACK,
   MEMSPACE_HEAP,
-  MEMSPACE_READONLY_DATA
+  MEMSPACE_READONLY_DATA,
+  MEMSPACE_THREAD_LOCAL
 };
 
 /* An enum for discriminating between the different concrete subclasses
@@ -49,6 +50,7 @@ enum region_kind
   RK_LABEL,
   RK_STACK,
   RK_HEAP,
+  RK_THREAD_LOCAL,
   RK_ROOT,
   RK_SYMBOLIC,
   RK_DECL,
@@ -62,6 +64,7 @@ enum region_kind
   RK_STRING,
   RK_BIT_RANGE,
   RK_VAR_ARG,
+  RK_ERRNO,
   RK_UNKNOWN,
 };
 
@@ -77,6 +80,8 @@ enum region_kind
        code_region (RK_CODE): represents the code segment, containing functions
        stack_region (RK_STACK): a stack, containing all stack frames
        heap_region (RK_HEAP): the heap, containing heap_allocated_regions
+       thread_local_region (RK_THREAD_LOCAL): thread-local data for the thread
+                                              being analyzed
      root_region (RK_ROOT): the top-level region
      function_region (RK_FUNCTION): the code for a particular function
      label_region (RK_LABEL): a particular label within a function
@@ -102,6 +107,7 @@ enum region_kind
 				      within another region
      var_arg_region (RK_VAR_ARG): a region for the N-th vararg within a
 				  frame_region for a variadic call
+     errno_region (RK_ERRNO): a region for holding "errno"
      unknown_region (RK_UNKNOWN): for handling unimplemented tree codes.  */
 
 /* Abstract base class for representing ways of accessing chunks of memory.
@@ -555,6 +561,32 @@ is_a_helper <const heap_region *>::test (const region *reg)
 
 namespace ana {
 
+/* Concrete space_region subclass: thread-local data for the thread
+   being analyzed.  */
+
+class thread_local_region : public space_region
+{
+public:
+  thread_local_region (unsigned id, region *parent)
+  : space_region (id, parent)
+  {}
+
+  enum region_kind get_kind () const final override { return RK_THREAD_LOCAL; }
+  void dump_to_pp (pretty_printer *pp, bool simple) const final override;
+};
+
+} // namespace ana
+
+template <>
+template <>
+inline bool
+is_a_helper <const thread_local_region *>::test (const region *reg)
+{
+  return reg->get_kind () == RK_THREAD_LOCAL;
+}
+
+namespace ana {
+
 /* Concrete region subclass.  The root region, containing all regions
    (either directly, or as descendents).
    Unique within a region_model_manager.  */
@@ -1362,6 +1394,32 @@ template <> struct default_hash_traits<var_arg_region::key_t>
 
 namespace ana {
 
+/* A region for errno for the current thread.  */
+
+class errno_region : public region
+{
+public:
+  errno_region (unsigned id, const thread_local_region *parent)
+  : region (complexity (parent), id, parent, integer_type_node)
+  {}
+
+  enum region_kind get_kind () const final override { return RK_ERRNO; }
+
+  void dump_to_pp (pretty_printer *pp, bool simple) const final override;
+};
+
+} // namespace ana
+
+template <>
+template <>
+inline bool
+is_a_helper <const errno_region *>::test (const region *reg)
+{
+  return reg->get_kind () == RK_ERRNO;
+}
+
+namespace ana {
+
 /* An unknown region, for handling unimplemented tree codes.  */
 
 class unknown_region : public region