xo-gc: refactor: move X1 object storage to new cls GCObjectStore.

src/gc/GCObjectStore.cpp

@@ -0,0 +1,108 @@
+/** @file GCObjectStore.cpp
+ *
+ *  @author Roland Conybeare, Apr 2026
+ **/
+
+#include "GCObjectStore.hpp"
+#include <xo/indentlog/scope.hpp>
+#include <cassert>
+
+namespace xo {
+    namespace mm {
+
+        GCObjectStore::GCObjectStore(const ArenaConfig & arena_cfg,
+                                     uint32_t ngen, bool debug_flag)
+        : arena_config_{arena_cfg},
+          n_generation_{ngen},
+          debug_flag_{debug_flag}
+        {
+            assert(arena_config_.header_.size_bits_ +
+                   arena_config_.header_.age_bits_ +
+                   arena_config_.header_.tseq_bits_ <= 64);
+
+            this->_init_space();
+        }
+
+        void
+        GCObjectStore::_init_space()
+        {
+            assert(c_n_role == 2);
+
+            for (uint32_t igen = 0, ngen = n_generation_; igen < ngen; ++igen) {
+                if (igen < c_max_generation) {
+                    {
+                        char buf[40];
+                        snprintf(buf, sizeof(buf), "x1-space-G%u-a", igen);
+
+                        this->space_storage_[0][igen]
+                            = DArena::map(arena_config_.with_name(std::string(buf)));
+                    }
+                    {
+                        char buf[40];
+                        snprintf(buf, sizeof(buf), "x1-space-G%u-b", igen);
+
+                        this->space_storage_[1][igen]
+                            = DArena::map(arena_config_.with_name(std::string(buf)));
+                    }
+
+                    this->space_[role::to_space()][igen] = &space_storage_[0][igen];
+                    this->space_[role::from_space()][igen] = &space_storage_[1][igen];
+                } else {
+                    assert(false);
+                }
+            }
+
+            for (uint32_t igen = n_generation_; igen < c_max_generation; ++igen) {
+                this->space_[role::to_space()][igen] = nullptr;
+                this->space_[role::from_space()][igen] = nullptr;
+            }
+
+            if (n_generation_ == 2) {
+                assert(this->get_space(role::to_space(), Generation{2}) == nullptr);
+            }
+        }
+
+        void
+        GCObjectStore::visit_pools(const MemorySizeVisitor & visitor) const
+        {
+            for (uint32_t j = 0; j < n_generation_; ++j) {
+                for (uint32_t i = 0; i < c_n_role; ++i) {
+                    space_storage_[i][j].visit_pools(visitor);
+                }
+            }
+        }
+
+        void
+        GCObjectStore::swap_roles(Generation upto) noexcept
+        {
+            scope log(XO_DEBUG(true), xtag("upto", upto));
+
+            for (Generation g = Generation{0}; g < upto; ++g) {
+                log && log("swap roles", xtag("g", g));
+
+                std::swap(space_[role::to_space()][g], space_[role::from_space()][g]);
+            }
+        }
+
+        void
+        GCObjectStore::cleanup_phase(Generation upto,
+                                     bool sanitize_flag)
+        {
+            scope log(XO_DEBUG(true), xtag("upto", upto));
+
+            // everything live has been copied out of from-space
+            // -> now set to empty
+            //
+            for (Generation g = Generation{0}; g < upto; ++g) {
+                if (sanitize_flag) {
+                    space_[role::from_space()][g]->scrub();
+                }
+
+                space_[role::from_space()][g]->clear();
+            }
+        }
+
+    } /*namespace mm*/
+} /*namespace xo*/
+
+/* end GCObjectStore.cpp */