Merge branch 'main' into feature/tagged-pointer

This reverts commit a318362d25.

.cspell.json

@@ -3,6 +3,7 @@
     "autogen",
     "autotools",
     "bdwgc",
+    "canonicalize",
     "cflag",
     "dealloc",
     "finalizer",

build.rs

@@ -23,7 +23,8 @@ fn main() {
 
     let dst = autotools::Config::new(LIB_GC_DIR)
         .cflag(format!(
-            "-I{} -L/lib/x86_64-linux-gnu -lpthread -fPIC -D POINTER_MASK=0x7",
+            // spell-checker: disable-next-line
+            "-I{} -L/lib/x86_64-linux-gnu -lpthread -fPIC",
             dst.join("include").display()
         ))
         .build();
@@ -59,10 +60,7 @@ fn main() {
     let dst = Config::new(LIB_GC_DIR)
         .profile("Release")
         .define("BUILD_SHARED_LIBS", "FALSE")
-        .cflag(format!(
-            "-I{} -DPOINTER_MASK=0x7",
-            libatomic_include_path, foo
-        ))
+        .cflag(format!("-I{}", libatomic_include_path))
         .build();
 
     println!(

examples/Cargo.toml

@@ -5,4 +5,5 @@ members = [
   "free_by_borrow",
   "free_by_gc",
   "static_threads",
+  "tagged_pointer",
 ]

examples/tagged_pointer/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "tagged_pointer"
+version = "0.1.0"
+authors = ["Yota Toyama <raviqqe@gmail.com>"]
+edition = "2021"
+publish = false
+
+[dependencies]
+bdwgc-alloc = { path = "../.." }

examples/tagged_pointer/src/main.rs

@@ -0,0 +1,27 @@
+use bdwgc_alloc::Allocator;
+use std::alloc::{alloc, Layout};
+
+const BITS: usize = usize::MAX << 48 | 0x7;
+
+#[global_allocator]
+static GLOBAL_ALLOCATOR: Allocator = Allocator;
+
+fn main() {
+    unsafe { Allocator::initialize() }
+
+    loop {
+        let x = allocate();
+        unsafe { *x = 42 };
+        let x = x as usize | BITS;
+
+        assert_eq!(x & BITS, BITS);
+
+        Allocator::force_collect();
+
+        assert_eq!(unsafe { *((x & !BITS) as *mut usize) }, 42);
+    }
+}
+
+fn allocate() -> *mut usize {
+    (unsafe { alloc(Layout::from_size_align(1 << 8, 8).unwrap()) }) as *mut usize
+}

src/lib.rs

@@ -25,7 +25,6 @@ extern "C" {
     fn GC_get_stack_base(stack_base: *mut GcStackBase) -> c_int;
     fn GC_init();
     fn GC_malloc(size: size_t) -> *mut c_void;
-    fn GC_memalign(align: size_t, size: size_t) -> *mut c_void;
     fn GC_realloc(ptr: *mut c_void, size: size_t) -> *mut c_void;
     fn GC_register_my_thread(stack_base: *const GcStackBase) -> c_int;
     fn GC_set_stackbottom(thread: *const c_void, stack_bottom: *const GcStackBase);
@@ -127,7 +126,7 @@ impl Allocator {
 
 unsafe impl GlobalAlloc for Allocator {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-        GC_memalign(layout.align(), layout.size()) as *mut u8
+        GC_malloc(layout.size()) as *mut u8
     }
 
     unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {