1 files changed, 108 insertions, 0 deletions
diff --git a/gcell/src/lib/runtime/gc_jd_stack.c b/gcell/src/lib/runtime/gc_jd_stack.c
new file mode 100644
index 000000000..0fffc0d1f
--- /dev/null
+++ b/gcell/src/lib/runtime/gc_jd_stack.c
@@ -0,0 +1,108 @@
+/* -*- c -*- */
+/*
+ * Copyright 2007 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "gc_jd_stack.h"
+#include "memory_barrier.h"
+
+
+void 
+gc_jd_stack_init(gc_jd_stack_t *stack)
+{
+  stack->top = 0;
+}
+  
+
+#ifdef __powerpc64__  // 64-bit mode
+
+void 
+gc_jd_stack_push(gc_jd_stack_t *stack, gc_job_desc_t *item)
+{
+  gc_eaddr_t	top;
+  gc_eaddr_t	item_ea = ptr_to_ea(item);
+  unsigned int	done;
+
+  do {
+    top = __ldarx(&stack->top);
+    item->sys.next = top;
+    smp_wmb();	      // order store of item->next before store of stack->top
+    done = __stdcx(&stack->top, item_ea);
+  } while (unlikely(done == 0));
+}
+
+gc_job_desc_t *
+gc_jd_stack_pop(gc_jd_stack_t *stack)
+{
+  gc_eaddr_t	s;
+  gc_eaddr_t	t;
+  unsigned int	done;
+
+  do {
+    s  = __ldarx(&stack->top);
+    if (s == 0)			/* stack's empty */
+      return 0;
+    t = ((gc_job_desc_t *) ea_to_ptr(s))->sys.next;
+    done = __stdcx(&stack->top, t);
+  } while (unlikely(done == 0));
+
+  return ea_to_ptr(s);
+}
+
+#else  // 32-bit mode
+
+/*
+ * In 32-bit mode, gc_eaddr's will have the top 32-bits zero.
+ * The ldarx/stdcx instructions aren't available in 32-bit mode,
+ * thus we use lwarx/stwcx on the low 32-bits of the 64-bit addresses.
+ * Since we're big-endian, the low 32-bits are at word offset 1.
+ */
+void 
+gc_jd_stack_push(gc_jd_stack_t *stack, gc_job_desc_t *item)
+{
+  gc_eaddr_t	top;
+  unsigned int	done;
+
+  do {
+    top = __lwarx((int32_t *)(&stack->top) + 1);
+    item->sys.next = top;
+    smp_wmb();	      // order store of item->sys.next before store of stack->top
+    done = __stwcx((int32_t *)(&stack->top) + 1, item);
+  } while (unlikely(done == 0));
+}
+
+gc_job_desc_t *
+gc_jd_stack_pop(gc_jd_stack_t *stack)
+{
+  gc_eaddr_t	s;
+  gc_eaddr_t	t;
+  unsigned int	done;
+
+  do {
+    s  = __lwarx((int32_t *)(&stack->top) + 1);
+    if (s == 0)			/* stack's empty */
+      return 0;
+    t = ((gc_job_desc_t *) ea_to_ptr(s))->sys.next;
+    done = __stwcx((int32_t *)(&stack->top) + 1, (uint32_t) t);
+  } while (unlikely(done == 0));
+
+  return ea_to_ptr(s);
+}
+
+#endif