Add GC support for GC_MALLOC_UNCOLLECTABLE.

3 files changed, 20 insertions, 5 deletions

diff --git a/src/library_gc.js b/src/library_gc.js
index fe4cbf63..ed40fa6c 100644
--- a/src/library_gc.js
+++ b/src/library_gc.js
@@ -9,6 +9,7 @@ if (GC_SUPPORT) {
 
       sizes: {}, // if in this map, then a live allocated object. this is iterable
       scannables: {},
+      uncollectables: {},
       finalizers: {},
       finalizerArgs: {},
 
@@ -34,7 +35,7 @@ if (GC_SUPPORT) {
         }
       },
 
-      malloc: function(bytes, clear, scannable) {
+      malloc: function(bytes, clear, scannable, collectable) {
         if (!bytes) return 0;
         var ptr;
         if (clear) {
@@ -42,6 +43,9 @@ if (GC_SUPPORT) {
         } else {
           ptr = _malloc(bytes);
         }
+        if (!collectable) {
+          GC.uncollectables[ptr] = true;
+        }
         GC.scannables[ptr] = scannable;
         GC.sizes[ptr] = bytes;
         GC.totalAllocations += bytes;
@@ -123,7 +127,7 @@ if (GC_SUPPORT) {
       sweep: function() { // traverse all objects and free all unreachable
         var freeList = [];
         for (var ptr in GC.sizes) {
-          if (!GC.reachable[ptr]) {
+          if (!GC.reachable[ptr] && !GC.uncollectables[ptr]) {
             freeList.push(parseInt(ptr));
           }
         }
@@ -140,12 +144,17 @@ if (GC_SUPPORT) {
 
     GC_MALLOC__deps: ['$GC'],
     GC_MALLOC: function(bytes) {
-      return GC.malloc(bytes, true, true);
+      return GC.malloc(bytes, true, true, true);
     },
 
     GC_MALLOC_ATOMIC__deps: ['$GC'],
     GC_MALLOC_ATOMIC: function(bytes) {
-      return GC.malloc(bytes, false, false);
+      return GC.malloc(bytes, false, false, true);
+    },
+
+    GC_MALLOC_UNCOLLECTABLE__deps: ['$GC'],
+    GC_MALLOC_UNCOLLECTABLE: function(bytes) {
+      return GC.malloc(bytes, true, true, false);
     },
 
     GC_FREE__deps: ['$GC'],
diff --git a/system/include/gc.h b/system/include/gc.h
index e0419dcb..e4593c51 100644
--- a/system/include/gc.h
+++ b/system/include/gc.h
@@ -29,6 +29,9 @@ void *GC_MALLOC(int bytes);
 /* Allocate memory for an object that the user promises will not contain pointers. */
 void *GC_MALLOC_ATOMIC(int bytes);
 
+/* Allocate memory that might container pointers but that can't be collected. */
+void *GC_MALLOC_UNCOLLECTABLE(int bytes);
+
 /* Explicitly deallocate an object. Dangerous as it forces a free and does not check if the object is reffed. */
 void GC_FREE(void *ptr);
 
diff --git a/tests/runner.py b/tests/runner.py
index 06b74caa..6d1a3cba 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -7893,7 +7893,7 @@ def process(filename):
         int main() {
           GC_INIT();
 
-          void *local, *local2, *local3, *local4;
+          void *local, *local2, *local3, *local4, *local5;
 
           // Hold on to global, drop locals
 
@@ -7938,6 +7938,9 @@ def process(filename):
           GC_REGISTER_FINALIZER_NO_ORDER(local3, finalizer, (void*)3, 0, 0);
           local4 = GC_MALLOC(12);
           GC_REGISTER_FINALIZER_NO_ORDER(local4, finalizer, (void*)4, 0, 0);
+          local5 = GC_MALLOC_UNCOLLECTABLE(12);
+          // This should never trigger since local5 is uncollectable
+          GC_REGISTER_FINALIZER_NO_ORDER(local5, finalizer, (void*)5, 0, 0);
 
           void **globalData = (void**)global;
           globalData[0] = local;