Add a way to remove a global

Author: antoyo

gcc/jit/jit-playback.cc

@@ -780,20 +780,30 @@ global_new_decl (location *loc,
 		 enum global_var_flags flags,
 		 const std::vector<std::pair<gcc_jit_variable_attribute,
 					     std::string>> &attributes,
-		 bool readonly)
+		 bool readonly,
+                 bool removed)
 {
   gcc_assert (type);
   gcc_assert (name);
 
   tree type_tree = type->as_tree ();
 
+  if (removed)
+  {
+    tree inner = build_decl (UNKNOWN_LOCATION, VAR_DECL,
+			   get_identifier (name),
+			   type_tree);
+    // TODO: make it weak?
+    DECL_EXTERNAL (inner) = 1;
+    return inner;
+  }
+
   tree inner = build_decl (UNKNOWN_LOCATION, VAR_DECL,
 			   get_identifier (name),
 			   type_tree);
 
   TREE_PUBLIC (inner) = (kind != GCC_JIT_GLOBAL_INTERNAL);
 
-
   int will_be_init = flags & (GLOBAL_VAR_FLAGS_WILL_BE_RVAL_INIT |
 			      GLOBAL_VAR_FLAGS_WILL_BE_BLOB_INIT);
 
@@ -855,9 +865,10 @@ set_variable_string_attribute (
 
 playback::lvalue *
 playback::context::
-global_finalize_lvalue (tree inner)
+global_finalize_lvalue (tree inner, bool removed)
 {
-  m_globals.safe_push (inner);
+  if (!removed)
+    m_globals.safe_push (inner);
 
   return new lvalue (this, inner);
 }
@@ -873,12 +884,13 @@ new_global (location *loc,
 	    enum global_var_flags flags,
 	    const std::vector<std::pair<gcc_jit_variable_attribute,
 					std::string>> &attributes,
-	    bool readonly)
+	    bool readonly,
+            bool removed)
 {
   tree inner =
-    global_new_decl (loc, kind, type, name, flags, attributes, readonly);
+    global_new_decl (loc, kind, type, name, flags, attributes, readonly, removed);
 
-  return global_finalize_lvalue (inner);
+  return global_finalize_lvalue (inner, removed);
 }
 
 void
@@ -1024,9 +1036,10 @@ new_global_initialized (location *loc,
 			enum global_var_flags flags,
 			const std::vector<std::pair<gcc_jit_variable_attribute,
 						    std::string>> &attributes,
-			bool readonly)
+			bool readonly,
+                        bool removed)
 {
-  tree inner = global_new_decl (loc, kind, type, name, flags, attributes, readonly);
+  tree inner = global_new_decl (loc, kind, type, name, flags, attributes, readonly, removed);
 
   vec<constructor_elt, va_gc> *constructor_elements = NULL;
 
@@ -1060,7 +1073,7 @@ new_global_initialized (location *loc,
   /* Compare with 'store_init_value' c-typeck.cc:7555.  */
   DECL_INITIAL (inner) = ctor;
 
-  return global_finalize_lvalue (inner);
+  return global_finalize_lvalue (inner, removed);
 }
 
 /* Implementation of the various

gcc/jit/jit-playback.h

@@ -137,7 +137,8 @@ class context : public log_user
 	      enum global_var_flags flags,
 	      const std::vector<std::pair<gcc_jit_variable_attribute,
 					  std::string>> &attributes,
-	      bool readonly);
+	      bool readonly,
+              bool removed);
 
   lvalue *
   new_global_initialized (location *loc,
@@ -152,7 +153,8 @@ class context : public log_user
 					    gcc_jit_variable_attribute,
 					    std::string>>
 					    &attributes,
-			  bool readonly);
+			  bool readonly,
+                          bool removed);
 
   rvalue *
   new_ctor (location *log,
@@ -362,9 +364,10 @@ class context : public log_user
 		   enum global_var_flags flags,
 		   const std::vector<std::pair<gcc_jit_variable_attribute,
 					       std::string>> &attributes,
-		   bool readonly);
+		   bool readonly,
+                   bool removed);
   lvalue *
-  global_finalize_lvalue (tree inner);
+  global_finalize_lvalue (tree inner, bool removed);
 
 private:
 

gcc/jit/jit-recording.cc

@@ -5412,14 +5412,16 @@ recording::global::replay_into (replayer *r)
 				 playback_string (m_name),
 				 m_flags,
 				 m_string_attributes,
-				 m_readonly)
+				 m_readonly,
+                                 m_removed)
     : r->new_global (playback_location (r, m_loc),
 		     m_kind,
 		     m_type->playback_type (),
 		     playback_string (m_name),
 		     m_flags,
 		     m_string_attributes,
-		     m_readonly);
+		     m_readonly,
+                     m_removed);
 
   if (m_tls_model != GCC_JIT_TLS_MODEL_NONE)
     global->set_tls_model (recording::tls_models[m_tls_model]);

gcc/jit/jit-recording.h

@@ -1460,6 +1460,11 @@ class lvalue : public rvalue
     m_readonly = true;
   }
 
+  void remove ()
+  {
+    m_removed = true;
+  }
+
   virtual const char *access_as_lvalue (reproducer &r);
   virtual bool is_global () const { return false; }
   virtual bool is_local () const { return false; }
@@ -1477,6 +1482,7 @@ class lvalue : public rvalue
   std::vector<std::pair<gcc_jit_variable_attribute,
 	      std::string>> m_string_attributes;
   bool m_readonly = false;
+  bool m_removed = false;
 };
 
 class param : public lvalue

gcc/jit/libgccjit.cc

@@ -2007,6 +2007,12 @@ gcc_jit_rvalue_get_type (gcc_jit_rvalue *rvalue)
   return static_cast <gcc_jit_type *> (rvalue->get_type ());
 }
 
+void
+gcc_jit_lvalue_remove (gcc_jit_lvalue *lvalue)
+{
+  lvalue->remove ();
+}
+
 /* Verify that NUMERIC_TYPE is non-NULL, and that it is a "numeric"
    type i.e. it satisfies gcc::jit::type::is_numeric (), such as the
    result of gcc_jit_context_get_type (GCC_JIT_TYPE_INT).  */

gcc/jit/libgccjit.h

@@ -1084,6 +1084,9 @@ gcc_jit_rvalue_as_object (gcc_jit_rvalue *rvalue);
 extern gcc_jit_type *
 gcc_jit_rvalue_get_type (gcc_jit_rvalue *rvalue);
 
+extern void
+gcc_jit_lvalue_remove (gcc_jit_lvalue *lvalue);
+
 /* Integer constants. */
 extern gcc_jit_rvalue *
 gcc_jit_context_new_rvalue_from_int (gcc_jit_context *ctxt,

gcc/jit/libgccjit.map

@@ -364,3 +364,17 @@ LIBGCCJIT_ABI_40 {
   global:
     gcc_jit_type_is_floating_point;
 } LIBGCCJIT_ABI_39;
+
+LIBGCCJIT_ABI_41 {
+   global:
+    gcc_jit_lvalue_remove;
+} LIBGCCJIT_ABI_40;
+
+LIBGCCJIT_ABI_42 {
+   global:
+    gcc_jit_rvalue_set_type;
+} LIBGCCJIT_ABI_41;
+
+LIBGCCJIT_ABI_43 {
+    gcc_jit_lvalue_add_attribute;
+} LIBGCCJIT_ABI_42;