Merge internal/rgengc.h and internal/gc.h

3 files changed, 424 insertions, 3 deletions

diff --git a/include/ruby/internal/core/rarray.h b/include/ruby/internal/core/rarray.h
index c3bb40be25..8fc3062f1b 100644
--- a/include/ruby/internal/core/rarray.h
+++ b/include/ruby/internal/core/rarray.h
@@ -29,7 +29,7 @@
 #include "ruby/internal/core/rbasic.h"
 #include "ruby/internal/dllexport.h"
 #include "ruby/internal/fl_type.h"
-#include "ruby/internal/rgengc.h"
+#include "ruby/internal/gc.h"
 #include "ruby/internal/stdbool.h"
 #include "ruby/internal/value.h"
 #include "ruby/internal/value_type.h"
diff --git a/include/ruby/internal/gc.h b/include/ruby/internal/gc.h
index 0129560cba..fb14b34211 100644
--- a/include/ruby/internal/gc.h
+++ b/include/ruby/internal/gc.h
@@ -20,7 +20,6 @@
  *             extension libraries.  They could be written in C++98.
  * @brief      Registering values to the GC.
  */
-
 #include "ruby/internal/config.h"
 
 #ifdef STDC_HEADERS
@@ -31,11 +30,16 @@
 # include <sys/types.h>                    /* ssize_t */
 #endif
 
+#include "ruby/assert.h"
 #include "ruby/internal/attr/cold.h"
 #include "ruby/internal/attr/nonnull.h"
 #include "ruby/internal/attr/noreturn.h"
+#include "ruby/internal/attr/artificial.h"
+#include "ruby/internal/attr/maybe_unused.h"
 #include "ruby/internal/attr/pure.h"
 #include "ruby/internal/dllexport.h"
+#include "ruby/internal/special_consts.h"
+#include "ruby/internal/stdbool.h"
 #include "ruby/internal/value.h"
 
 RBIMPL_SYMBOL_EXPORT_BEGIN()
@@ -417,4 +421,422 @@ void rb_gc_register_mark_object(VALUE object);
 
 RBIMPL_SYMBOL_EXPORT_END()
 
+/**
+ * @private
+ *
+ * @deprecated  This macro once was a thing in the old days, but makes no sense
+ *              any  longer today.   Exists  here  for backwards  compatibility
+ *              only.  You can safely forget about it.
+ */
+#undef USE_RGENGC
+#define USE_RGENGC 1
+
+/**
+ * @private
+ *
+ * This is  a compile-time flag  to enable/disable incremental GC  feature.  It
+ * has to  be set at  the time  ruby itself compiles.   Makes no sense  for 3rd
+ * parties.  It is safe  for them to set this though;  that just doesn't change
+ * anything.
+ */
+#ifndef USE_RINCGC
+# define USE_RINCGC 1
+#endif
+
+/**
+ * @deprecated  This macro seems  broken.  Setting this to  anything other than
+ *              zero just doesn't compile.  We need to KonMari.
+ */
+#ifndef USE_RGENGC_LOGGING_WB_UNPROTECT
+# define USE_RGENGC_LOGGING_WB_UNPROTECT 0
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RArray.  It has to be set  at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_ARRAY
+# define RGENGC_WB_PROTECTED_ARRAY 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RHash.  It has  to be set at the time  ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_HASH
+# define RGENGC_WB_PROTECTED_HASH 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RStruct.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_STRUCT
+# define RGENGC_WB_PROTECTED_STRUCT 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RString.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_STRING
+# define RGENGC_WB_PROTECTED_STRING 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RObject.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_OBJECT
+# define RGENGC_WB_PROTECTED_OBJECT 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RRegexp.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_REGEXP
+# define RGENGC_WB_PROTECTED_REGEXP 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RMatch.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_MATCH
+# define RGENGC_WB_PROTECTED_MATCH 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RClass.  It has to be set  at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_CLASS
+# define RGENGC_WB_PROTECTED_CLASS 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RFloat.  It has to be set  at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_FLOAT
+# define RGENGC_WB_PROTECTED_FLOAT 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RComplex.   It has  to be  set at  the time  ruby itself  compiles.
+ * Makes no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_COMPLEX
+# define RGENGC_WB_PROTECTED_COMPLEX 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RRational.  It  has to  be set  at the  time ruby  itself compiles.
+ * Makes no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_RATIONAL
+# define RGENGC_WB_PROTECTED_RATIONAL 1
+#endif
+
+/**
+ * @private
+ *
+ * This  is   a  compile-time   flag  to   enable/disable  write   barrier  for
+ * struct ::RBignum.  It has to be set at the time ruby itself compiles.  Makes
+ * no sense for 3rd parties.
+ */
+#ifndef RGENGC_WB_PROTECTED_BIGNUM
+# define RGENGC_WB_PROTECTED_BIGNUM 1
+#endif
+
+/**
+ * @private
+ *
+ * @deprecated  This macro once was a thing in the old days, but makes no sense
+ *              any  longer today.   Exists  here  for backwards  compatibility
+ *              only.  You can safely forget about it.
+ *
+ * @internal
+ *
+ * @shyouhei doesn't think anybody uses this right now.
+ */
+#ifndef RGENGC_WB_PROTECTED_NODE_CREF
+# define RGENGC_WB_PROTECTED_NODE_CREF 1
+#endif
+
+/**
+ * @defgroup rgengc Write barrier (WB) interfaces:
+ *
+ * @note The following  core interfaces can  be changed in the  future.  Please
+ *       catch up if you want to insert WB into C-extensions correctly.
+ *
+ * @{
+ */
+
+/**
+ * Declaration of a "back" pointer.  This  is a write barrier for new reference
+ * from  "old"  generation  to  "young" generation.   It  writes  `young`  into
+ * `*slot`, which is a pointer inside of `old`.
+ *
+ * @param[in]   old    An old object.
+ * @param[in]   slot   A pointer inside of `old`.
+ * @param[out]  young  A young object.
+ */
+#define RB_OBJ_WRITE(old, slot, young) \
+    RBIMPL_CAST(rb_obj_write((VALUE)(old), (VALUE *)(slot), (VALUE)(young), __FILE__, __LINE__))
+
+/**
+ * Identical to #RB_OBJ_WRITE(), except it doesn't write any values, but only a
+ * WB declaration.   `oldv` is  replaced value  with `b`  (not used  in current
+ * Ruby).
+ *
+ * @param[in]   old    An old object.
+ * @param[in]   oldv   An object previously stored inside of `old`.
+ * @param[out]  young  A young object.
+ */
+#define RB_OBJ_WRITTEN(old, oldv, young) \
+    RBIMPL_CAST(rb_obj_written((VALUE)(old), (VALUE)(oldv), (VALUE)(young), __FILE__, __LINE__))
+/** @} */
+
+#define OBJ_PROMOTED_RAW RB_OBJ_PROMOTED_RAW /**< @old{RB_OBJ_PROMOTED_RAW} */
+#define OBJ_PROMOTED     RB_OBJ_PROMOTED     /**< @old{RB_OBJ_PROMOTED} */
+#define OBJ_WB_UNPROTECT RB_OBJ_WB_UNPROTECT /**< @old{RB_OBJ_WB_UNPROTECT} */
+
+/**
+ * Asserts that the passed object is  not fenced by write barriers.  Objects of
+ * such  property do  not contribute  to  generational GCs.   They are  scanned
+ * always.
+ *
+ * @param[out]  x  An object that would not be protected by the barrier.
+ */
+#define RB_OBJ_WB_UNPROTECT(x) rb_obj_wb_unprotect(x, __FILE__, __LINE__)
+
+/**
+ * Identical  to #RB_OBJ_WB_UNPROTECT(),  except it  can also  assert that  the
+ * given object is of given type.
+ *
+ * @param[in]   type  One of `ARRAY`, `STRING`, etc.
+ * @param[out]  obj   An object of `type` that would not be protected.
+ *
+ * @internal
+ *
+ * @shyouhei doesn't understand why this has to be visible from extensions.
+ */
+#define RB_OBJ_WB_UNPROTECT_FOR(type, obj) \
+    (RGENGC_WB_PROTECTED_##type ? OBJ_WB_UNPROTECT(obj) : obj)
+
+/**
+ * @private
+ *
+ * This is an implementation detail of rb_obj_wb_unprotect().  People don't use
+ * it directly.
+ */
+#define RGENGC_LOGGING_WB_UNPROTECT rb_gc_unprotect_logging
+
+/** @cond INTERNAL_MACRO */
+#define RB_OBJ_PROMOTED_RAW RB_OBJ_PROMOTED_RAW
+#define RB_OBJ_PROMOTED     RB_OBJ_PROMOTED
+/** @endcond */
+
+RBIMPL_SYMBOL_EXPORT_BEGIN()
+/**
+ * This  is  the  implementation  of  #RB_OBJ_WRITE().   People  don't  use  it
+ * directly.
+ *
+ * @param[in]   old    An object that points to `young`.
+ * @param[out]  young  An object that is referenced from `old`.
+ */
+void rb_gc_writebarrier(VALUE old, VALUE young);
+
+/**
+ * This is the  implementation of #RB_OBJ_WB_UNPROTECT().  People  don't use it
+ * directly.
+ *
+ * @param[out] obj  An object that does not participate in WB.
+ */
+void rb_gc_writebarrier_unprotect(VALUE obj);
+
+#if USE_RGENGC_LOGGING_WB_UNPROTECT
+/**
+ * @private
+ *
+ * This  is  the   implementation  of  #RGENGC_LOGGING_WB_UNPROTECT().   People
+ * don't use it directly.
+ *
+ * @param[in]  objptr    Don't  know why  this  is  a pointer  to  void but  in
+ *                       reality this is  a pointer to an object  that is about
+ *                       to be un-protected.
+ * @param[in]  filename  Pass C's `__FILE__` here.
+ * @param[in]  line      Pass C's `__LINE__` here.
+ */
+void rb_gc_unprotect_logging(void *objptr, const char *filename, int line);
+#endif
+
+RBIMPL_SYMBOL_EXPORT_END()
+
+RBIMPL_ATTR_PURE_UNLESS_DEBUG()
+RBIMPL_ATTR_ARTIFICIAL()
+/**
+ * This  is the  implementation  of #RB_OBJ_PROMOTED().   People  don't use  it
+ * directly.
+ *
+ * @param[in]  obj    An object to query.
+ * @retval     true   The object is "promoted".
+ * @retval     false  The object is young.  Have not experienced GC at all.
+ */
+static inline bool
+RB_OBJ_PROMOTED_RAW(VALUE obj)
+{
+    RBIMPL_ASSERT_OR_ASSUME(RB_FL_ABLE(obj));
+    return RB_FL_ANY_RAW(obj,  RUBY_FL_PROMOTED);
+}
+
+RBIMPL_ATTR_PURE_UNLESS_DEBUG()
+RBIMPL_ATTR_ARTIFICIAL()
+/**
+ * Tests if the object is "promoted" -- that is, whether the object experienced
+ * one or more GC marks.
+ *
+ * @param[in]  obj    An object to query.
+ * @retval     true   The object is "promoted".
+ * @retval     false  The object is young.  Have not experienced GC at all.
+ * @note       Hello, is anyone actively calling this function?  @shyouhei have
+ *             never seen  any actual usages  outside of the  GC implementation
+ *             itself.
+ */
+static inline bool
+RB_OBJ_PROMOTED(VALUE obj)
+{
+    if (! RB_FL_ABLE(obj)) {
+        return false;
+    }
+    else {
+        return RB_OBJ_PROMOTED_RAW(obj);
+    }
+}
+
+/**
+ * This is the  implementation of #RB_OBJ_WB_UNPROTECT().  People  don't use it
+ * directly.
+ *
+ * @param[out]  x         An object that does not participate in WB.
+ * @param[in]   filename  C's `__FILE__` of the caller function.
+ * @param[in]   line      C's `__LINE__` of the caller function.
+ * @return      x
+ */
+static inline VALUE
+rb_obj_wb_unprotect(
+    VALUE x,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    const char *filename,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    int line)
+{
+#if USE_RGENGC_LOGGING_WB_UNPROTECT
+    RGENGC_LOGGING_WB_UNPROTECT(RBIMPL_CAST((void *)x), filename, line);
+#endif
+    rb_gc_writebarrier_unprotect(x);
+    return x;
+}
+
+/**
+ * @private
+ *
+ * This  is  the implementation  of  #RB_OBJ_WRITTEN().   People don't  use  it
+ * directly.
+ *
+ * @param[in]   a         An old object.
+ * @param[in]   oldv      An object previously stored inside of `old`.
+ * @param[out]  b         A young object.
+ * @param[in]   filename  C's `__FILE__` of the caller function.
+ * @param[in]   line      C's `__LINE__` of the caller function.
+ * @return      a
+ */
+static inline VALUE
+rb_obj_written(
+    VALUE a,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    VALUE oldv,
+    VALUE b,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    const char *filename,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    int line)
+{
+#if USE_RGENGC_LOGGING_WB_UNPROTECT
+    RGENGC_LOGGING_OBJ_WRITTEN(a, oldv, b, filename, line);
+#endif
+
+    if (!RB_SPECIAL_CONST_P(b)) {
+        rb_gc_writebarrier(a, b);
+    }
+
+    return a;
+}
+
+/**
+ * @private
+ *
+ * This  is  the  implementation  of  #RB_OBJ_WRITE().   People  don't  use  it
+ * directly.
+ *
+ * @param[in]   a         An old object.
+ * @param[in]   slot      A pointer inside of `old`.
+ * @param[out]  b         A young object.
+ * @param[in]   filename  C's `__FILE__` of the caller function.
+ * @param[in]   line      C's `__LINE__` of the caller function.
+ * @return      a
+ */
+static inline VALUE
+rb_obj_write(
+    VALUE a, VALUE *slot, VALUE b,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    const char *filename,
+    RBIMPL_ATTR_MAYBE_UNUSED()
+    int line)
+{
+#ifdef RGENGC_LOGGING_WRITE
+    RGENGC_LOGGING_WRITE(a, slot, b, filename, line);
+#endif
+
+    *slot = b;
+
+    rb_obj_written(a, RUBY_Qundef /* ignore `oldv' now */, b, filename, line);
+    return a;
+}
+
 #endif /* RBIMPL_GC_H */
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 444940ca3a..eb9a7e4d0f 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -43,7 +43,6 @@
 #include "ruby/internal/method.h"
 #include "ruby/internal/module.h"
 #include "ruby/internal/newobj.h"
-#include "ruby/internal/rgengc.h"
 #include "ruby/internal/scan_args.h"
 #include "ruby/internal/special_consts.h"
 #include "ruby/internal/symbol.h"