Merge softdevteam#53

53: Tweaks to Boehm multithreaded API r=ltratt a=jacob-hughes

These are some minor changes that need fixing before this can be used properly in rustgc. Mostly because I misunderstood the way the Boehm API works the first time around.

Co-authored-by: Jake Hughes <[email protected]>

Author: bors[bot]

allocator/build.rs

@@ -12,6 +12,7 @@ compile_error!("Requires x86_64 with 64 bit pointer width.");
 static POINTER_MASK: &str = "-DPOINTER_MASK=0xFFFFFFFFFFFFFFF8";
 static FPIC: &str = "-fPIC";
 static MULTITHREADED: &str = "-DGC_ALWAYS_MULTITHREADED";
+static NO_INCREMENTAL: &str = "-DGC_DISABLE_INCREMENTAL";
 
 fn run<F>(name: &str, mut configure: F)
 where
@@ -46,7 +47,10 @@ fn main() {
         run("./configure", |cmd| {
             cmd.arg("--enable-static").arg("--disable-shared").env(
                 "CFLAGS",
-                format!("{} {} {}", POINTER_MASK, FPIC, MULTITHREADED),
+                format!(
+                    "{} {} {} {}",
+                    POINTER_MASK, FPIC, MULTITHREADED, NO_INCREMENTAL
+                ),
             )
         });
 

allocator/src/boehm.rs

@@ -57,8 +57,6 @@ extern "C" {
 
     pub(crate) fn GC_gcollect();
 
-    pub(crate) fn GC_start_performance_measurement();
-
     pub(crate) fn GC_get_full_gc_total_time() -> usize;
 
     pub(crate) fn GC_get_prof_stats(prof_stats: *mut ProfileStats, stats_size: usize) -> usize;
@@ -77,4 +75,8 @@ extern "C" {
     pub(crate) fn GC_register_my_thread(stack_base: *mut u8) -> i32;
 
     pub(crate) fn GC_unregister_my_thread() -> i32;
+
+    pub(crate) fn GC_allow_register_threads();
+
+    pub(crate) fn GC_init();
 }

allocator/src/lib.rs

@@ -148,21 +148,25 @@ impl GcAllocator {
     }
 
     pub fn init() {
-        unsafe { boehm::GC_start_performance_measurement() };
+        unsafe { boehm::GC_init() }
     }
 
     /// Returns true if thread was successfully registered.
     pub unsafe fn register_thread(stack_base: *mut u8) -> bool {
-        boehm::GC_register_my_thread(stack_base) != 0
+        boehm::GC_register_my_thread(stack_base) == 0
     }
 
     /// Returns true if thread was successfully unregistered.
     pub unsafe fn unregister_thread() -> bool {
-        boehm::GC_unregister_my_thread() != 0
+        boehm::GC_unregister_my_thread() == 0
     }
 
     pub fn thread_registered() -> bool {
-        unsafe { boehm::GC_thread_is_registered() != 0 }
+        unsafe { boehm::GC_thread_is_registered() == 0 }
+    }
+
+    pub fn allow_register_threads() {
+        unsafe { boehm::GC_allow_register_threads() }
     }
 }