Changeset 280605 in webkit

Timestamp:

Aug 3, 2021 12:15:21 PM (3 years ago)

Author:

fpizlo@apple.com

Message:

pas_segmented_vector's iterate functions should handle memory ordering correctly
​https://bugs.webkit.org/show_bug.cgi?id=228746

Reviewed by Mark Lam.

Also fixed a missing store-store fence in bitfit_directory's use of a segmented vector.

• libpas/src/libpas/pas_bitfit_directory.c:

(pas_bitfit_directory_get_first_free_view):

• libpas/src/libpas/pas_segmented_vector.h:

Location:

trunk/Source/bmalloc

Files:

• ChangeLog (modified) (1 diff)
• libpas/src/libpas/pas_bitfit_directory.c (modified) (1 diff)
• libpas/src/libpas/pas_segmented_vector.h (modified) (2 diffs)

trunk/Source/bmalloc/ChangeLog

@@ +1 @@
+2021-08-03  Filip Pizlo  <fpizlo@apple.com>
+
+        pas_segmented_vector's iterate functions should handle memory ordering correctly
+        https://bugs.webkit.org/show_bug.cgi?id=228746
+
+        Reviewed by Mark Lam.
+
+        Also fixed a missing store-store fence in bitfit_directory's use of a segmented vector.
+
+        * libpas/src/libpas/pas_bitfit_directory.c:
+        (pas_bitfit_directory_get_first_free_view):
+        * libpas/src/libpas/pas_segmented_vector.h:
+
 2021-07-14  Michael Saboff  <msaboff@apple.com>
 

trunk/Source/bmalloc/libpas/src/libpas/pas_bitfit_directory.c

@@ -221 +221 @@
                     view = pas_bitfit_view_create(global_directory,
                                                   (unsigned)found_index.index);
+                    pas_store_store_fence();
                     pas_compact_atomic_bitfit_view_ptr_store(
                         pas_bitfit_directory_get_view_ptr(directory, found_index.index), view);

trunk/Source/bmalloc/libpas/src/libpas/pas_segmented_vector.h

@@ -164 +164 @@
         \
         size = vector->size; \
-        spine = name##_spine_ptr_load(&vector->spine); \
+        spine = name##_spine_ptr_load(&vector[pas_depend(size)].spine); \
         \
         for (; spine_index * segment_size < size; spine_index++) { \
@@ -256 +256 @@
         segment_index = start_index % (segment_size); \
         \
-        spine = name##_spine_ptr_load(&vector->spine); \
+        spine = name##_spine_ptr_load(&vector[pas_depend(size)].spine); \
         \
         spine_index++; \