[mycpp/runtime] Move field mask in ObjHeader, opening up obj_id

oilshell · Jan 2, 2023 · e3342ed · e3342ed
1 parent 28ce38e
commit e3342ed
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Showing 4 changed files with 25 additions and 25 deletions.
diff --git a/mycpp/demo/target_lang.cc b/mycpp/demo/target_lang.cc
@@ -529,7 +529,7 @@ class Derived : public Base {
  public:
   Derived(int i, int j) : Base(i), j(j) {
     // annoying: should be in initializer list
-    header_.field_mask |= 0x5;
+    FIELD_MASK(header_) |= 0x5;
   }
   int j;
   Node* three;

diff --git a/mycpp/gc_heap_test.cc b/mycpp/gc_heap_test.cc
@@ -50,7 +50,7 @@ TEST field_masks_test() {
   StackRoots _roots({&L});
 
   L->append(1);
-  log("List mask = %d", L->header_.field_mask);
+  log("List mask = %d", FIELD_MASK(L->header_));
 
   auto d = Alloc<Dict<Str*, int>>();
   StackRoots _roots2({&d});
@@ -63,7 +63,7 @@ TEST field_masks_test() {
   // expression!  Gah!
   // d->set(StrFromC("foo"), 3);
 
-  log("Dict mask = %d", d->header_.field_mask);
+  log("Dict mask = %d", FIELD_MASK(d->header_));
 
 #if 0
   ShowFixedChildren(L);
@@ -354,7 +354,7 @@ TEST vtable_test() {
     ShowObj(header);
 
     ASSERT_EQ_FMT(HeapTag::FixedSize, header->heap_tag, "%d");
-    ASSERT_EQ_FMT(0, header->field_mask, "%d");
+    ASSERT_EQ_FMT(0, FIELD_MASK(*header), "%d");
 #if 0
     // casts get rid of warning
     ASSERT_EQ_FMT((int)sizeof(DerivedObj), (int)header->obj_len, "%d");

diff --git a/mycpp/gc_obj.h b/mycpp/gc_obj.h
@@ -27,6 +27,7 @@ const unsigned kZeroMask = 0;  // for types with no pointers
 
 // no obj_len computed for global List/Slab/Dict
 const int kNoObjLen = 0x0badbeef;
+const int kNoObjId = 42;
 
 // The first member of every GC-managed object is 'ObjHeader header_'.
 // (There's no inheritance!)
@@ -35,8 +36,7 @@ struct ObjHeader {
                            // Overlaps with RawObject::points_to_header
   unsigned type_tag : 7;   // TypeTag, ASDL variant / shared variant
 #ifdef MARK_SWEEP
-  // TODO: change to obj_id
-  unsigned field_mask : 24;  // For some user-defined classes, so max 16 fields
+  unsigned obj_id : 24;  // For some user-defined classes, so max 16 fields
 #else
   unsigned field_mask : 24;  // Cheney needs field_maks AND obj_len
 #endif
@@ -52,7 +52,7 @@ struct ObjHeader {
 };
 
 #if MARK_SWEEP
-  #define FIELD_MASK(header) (header).field_mask
+  #define FIELD_MASK(header) (header).u_mask_npointers_strlen
   #define STR_LEN(header) (header).u_mask_npointers_strlen
   #define NUM_POINTERS(header) (header).u_mask_npointers_strlen
 #else
@@ -70,22 +70,22 @@ struct RawObject {
 // ObjHeader.  See mycpp/demo/gc_header.cc.
 
 // Used by hand-written and generated classes
-#define GC_CLASS_FIXED(header_, field_mask, obj_len)                        \
-  header_ {                                                                 \
-    kIsHeader, TypeTag::OtherClass, field_mask, HeapTag::FixedSize, obj_len \
+#define GC_CLASS_FIXED(header_, field_mask, obj_len)                         \
+  header_ {                                                                  \
+    kIsHeader, TypeTag::OtherClass, kNoObjId, HeapTag::FixedSize, field_mask \
   }
 
 // Used by mycpp and frontend/flag_gen.py.  TODO: Sort fields and use
 // HeapTag::Scanned.
-#define GC_CLASS(header_, heap_tag, field_mask, obj_len)          \
-  header_ {                                                       \
-    kIsHeader, TypeTag::OtherClass, field_mask, heap_tag, obj_len \
+#define GC_CLASS(header_, heap_tag, field_mask, obj_len)           \
+  header_ {                                                        \
+    kIsHeader, TypeTag::OtherClass, kNoObjId, heap_tag, field_mask \
   }
 
 // Used by ASDL.  TODO: Sort fields and use HeapTag::Scanned
-#define GC_ASDL_CLASS(header_, type_tag, field_mask, obj_len)    \
-  header_ {                                                      \
-    kIsHeader, type_tag, field_mask, HeapTag::FixedSize, obj_len \
+#define GC_ASDL_CLASS(header_, type_tag, field_mask, obj_len)     \
+  header_ {                                                       \
+    kIsHeader, type_tag, kNoObjId, HeapTag::FixedSize, field_mask \
   }
 
 #define GC_STR(header_)                                            \
@@ -98,9 +98,9 @@ struct RawObject {
     kIsHeader, TypeTag::Slab, kZeroMask, heap_tag, num_pointers \
   }
 
-#define GC_TUPLE(header_, field_mask, obj_len)                         \
-  header_ {                                                            \
-    kIsHeader, TypeTag::Tuple, field_mask, HeapTag::FixedSize, obj_len \
+#define GC_TUPLE(header_, field_mask, obj_len)                          \
+  header_ {                                                             \
+    kIsHeader, TypeTag::Tuple, kNoObjId, HeapTag::FixedSize, field_mask \
   }
 
 // TODO: could omit this in BUMP_LEAK mode

diff --git a/mycpp/gc_tuple_test.cc b/mycpp/gc_tuple_test.cc
@@ -3,25 +3,25 @@
 
 TEST tuple_field_masks_test() {
   Tuple2<Str *, Str *> ss(nullptr, nullptr);
-  ASSERT_EQ_FMT(0b11, ss.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b11, FIELD_MASK(ss.header_), "%d");
 
   // 8 + 4 on 64 bit
   Tuple2<Str *, int> si(nullptr, 42);
-  ASSERT_EQ_FMT(0b01, si.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b01, FIELD_MASK(si.header_), "%d");
 
   // 4 + 8 on 64 bit
   Tuple2<int, Str *> is(42, nullptr);
-  ASSERT_EQ_FMT(0b10, is.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b10, FIELD_MASK(is.header_), "%d");
 
   Tuple3<Str *, Str *, Str *> sss(nullptr, nullptr, nullptr);
-  ASSERT_EQ_FMT(0b111, sss.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b111, FIELD_MASK(sss.header_), "%d");
 
   Tuple3<int, Str *, Str *> iss(42, nullptr, nullptr);
-  ASSERT_EQ_FMT(0b110, iss.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b110, FIELD_MASK(iss.header_), "%d");
 
   // 4 + 4 + 8 + 8, so it's 0b110 not 0b1100
   Tuple4<int, int, Str *, Str *> iiss(42, 42, nullptr, nullptr);
-  ASSERT_EQ_FMT(0b110, iiss.header_.field_mask, "%d");
+  ASSERT_EQ_FMT(0b110, FIELD_MASK(iiss.header_), "%d");
 
   PASS();
 }