+/* STMT is a call that has been discovered noreturn. Fixup the CFG
+ and remove LHS. Return true if something changed. */
+
+bool
+fixup_noreturn_call (gimple stmt)
+{
+ basic_block bb = gimple_bb (stmt);
+ bool changed = false;
+
+ if (gimple_call_builtin_p (stmt, BUILT_IN_RETURN))
+ return false;
+
+ /* First split basic block if stmt is not last. */
+ if (stmt != gsi_stmt (gsi_last_bb (bb)))
+ split_block (bb, stmt);
+
+ changed |= remove_fallthru_edge (bb->succs);
+
+ /* If there is LHS, remove it. */
+ if (gimple_call_lhs (stmt))
+ {
+ tree op = gimple_call_lhs (stmt);
+ gimple_call_set_lhs (stmt, NULL_TREE);
+
+ /* We need to remove SSA name to avoid checking errors.
+ All uses are dominated by the noreturn and thus will
+ be removed afterwards.
+ We proactively remove affected non-PHI statements to avoid
+ fixup_cfg from trying to update them and crashing. */
+ if (TREE_CODE (op) == SSA_NAME)
+ {
+ use_operand_p use_p;
+ imm_use_iterator iter;
+ gimple use_stmt;
+ bitmap_iterator bi;
+ unsigned int bb_index;
+
+ bitmap blocks = BITMAP_ALLOC (NULL);
+
+ FOR_EACH_IMM_USE_STMT (use_stmt, iter, op)
+ {
+ if (gimple_code (use_stmt) != GIMPLE_PHI)
+ bitmap_set_bit (blocks, gimple_bb (use_stmt)->index);
+ else
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+ SET_USE (use_p, error_mark_node);
+ }
+ EXECUTE_IF_SET_IN_BITMAP (blocks, 0, bb_index, bi)
+ delete_basic_block (BASIC_BLOCK (bb_index));
+ BITMAP_FREE (blocks);
+ release_ssa_name (op);
+ }
+ update_stmt (stmt);
+ changed = true;
+ }
+ /* Similarly remove VDEF if there is any. */
+ else if (gimple_vdef (stmt))
+ update_stmt (stmt);
+ return changed;
+}
+
+