Initial commit to populate CoreCLR repo

[tfs-changeset: 1407945]

1 files changed, 105 insertions, 0 deletions

diff --git a/src/gc/gccommon.cpp b/src/gc/gccommon.cpp
new file mode 100644
index 0000000000..b7686056ae
--- /dev/null
+++ b/src/gc/gccommon.cpp
@@ -0,0 +1,105 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+
+/*
+ * GCCOMMON.CPP 
+ *
+ * Code common to both SVR and WKS gcs
+ */
+
+#include "common.h"
+
+#include "gcenv.h"
+#include "gc.h"
+
+#ifdef FEATURE_SVR_GC
+SVAL_IMPL_INIT(DWORD,GCHeap,gcHeapType,GCHeap::GC_HEAP_INVALID);
+#endif // FEATURE_SVR_GC
+
+GPTR_IMPL(GCHeap,g_pGCHeap);
+
+/* global versions of the card table and brick table */ 
+GPTR_IMPL(DWORD,g_card_table);
+
+/* absolute bounds of the GC memory */
+GPTR_IMPL_INIT(BYTE,g_lowest_address,0);
+GPTR_IMPL_INIT(BYTE,g_highest_address,0);
+
+#ifndef DACCESS_COMPILE
+
+BYTE* g_ephemeral_low = (BYTE*)1; 
+BYTE* g_ephemeral_high = (BYTE*)~0;
+
+#ifdef WRITE_BARRIER_CHECK
+BYTE* g_GCShadow;
+BYTE* g_GCShadowEnd;
+BYTE* g_shadow_lowest_address = NULL;
+#endif
+
+VOLATILE(LONG) m_GCLock = -1;
+
+LONG g_bLowMemoryFromHost = 0;
+
+#ifdef WRITE_BARRIER_CHECK
+
+#define INVALIDGCVALUE (LPVOID)((size_t)0xcccccccd)
+
+    // called by the write barrier to update the shadow heap
+void updateGCShadow(Object** ptr, Object* val)
+{
+    Object** shadow = (Object**) &g_GCShadow[((BYTE*) ptr - g_lowest_address)];
+    if ((BYTE*) shadow < g_GCShadowEnd)
+    {
+        *shadow = val;
+
+        // Ensure that the write to the shadow heap occurs before the read from
+        // the GC heap so that race conditions are caught by INVALIDGCVALUE.
+        MemoryBarrier();
+
+        if(*ptr!=val)
+            *shadow = (Object *) INVALIDGCVALUE;
+    }
+}
+
+#endif // WRITE_BARRIER_CHECK
+
+
+struct changed_seg
+{
+    BYTE              * start;
+    BYTE              * end;
+    size_t              gc_index;
+    bgc_state           bgc;
+    changed_seg_state   changed;
+};
+
+
+const int max_saved_changed_segs = 128;
+
+changed_seg saved_changed_segs[max_saved_changed_segs];
+int saved_changed_segs_count = 0;
+
+void record_changed_seg (BYTE* start, BYTE* end, 
+                         size_t current_gc_index, 
+                         bgc_state current_bgc_state,
+                         changed_seg_state changed_state)
+{
+    if (saved_changed_segs_count < max_saved_changed_segs)
+    {
+        saved_changed_segs[saved_changed_segs_count].start = start;
+        saved_changed_segs[saved_changed_segs_count].end = end;
+        saved_changed_segs[saved_changed_segs_count].gc_index = current_gc_index;
+        saved_changed_segs[saved_changed_segs_count].bgc = current_bgc_state;
+        saved_changed_segs[saved_changed_segs_count].changed = changed_state;
+        saved_changed_segs_count++;
+    }
+    else
+    {
+        saved_changed_segs_count = 0;
+    }
+}
+
+#endif // !DACCESS_COMPILE