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diff --git a/cdschecker_modified_benchmarks/mpmc-queue/mpmc-queue.h b/cdschecker_modified_benchmarks/mpmc-queue/mpmc-queue.h
new file mode 100644
index 0000000..f86bec4
--- /dev/null
+++ b/cdschecker_modified_benchmarks/mpmc-queue/mpmc-queue.h
@@ -0,0 +1,97 @@
+#include "cds_atomic.h"
+#include <unrelacy.h>
+
+template <typename t_element, size_t t_size>
+struct mpmc_boundq_1_alt
+{
+private:
+
+	// elements should generally be cache-line-size padded :
+	t_element               m_array[t_size];
+
+	// rdwr counts the reads & writes that have started
+	atomic<unsigned int>    m_rdwr;
+	// "read" and "written" count the number completed
+	atomic<unsigned int>    m_read;
+	atomic<unsigned int>    m_written;
+
+public:
+
+	mpmc_boundq_1_alt()
+	{
+		m_rdwr = 0;
+		m_read = 0;
+		m_written = 0;
+	}
+
+	//-----------------------------------------------------
+
+	t_element * read_fetch() {
+		unsigned int rdwr = m_rdwr.load(mo_acquire);
+		unsigned int rd,wr;
+		for(;;) {
+			rd = (rdwr>>16) & 0xFFFF;
+			wr = rdwr & 0xFFFF;
+
+			if ( wr == rd ) // empty
+				return NULL;
+
+			if ( m_rdwr.compare_exchange_weak(rdwr,rdwr+(1<<16),mo_acquire) )
+				break;
+			else
+				thrd_yield();
+		}
+
+		// (*1)
+		rl::backoff bo;
+		while ( (m_written.load(mo_acquire) & 0xFFFF) != wr ) {
+			thrd_yield();
+		}
+
+		t_element * p = & ( m_array[ rd % t_size ] );
+
+		return p;
+	}
+
+	void read_consume() {
+		m_read.fetch_add(1,mo_release);
+	}
+
+	//-----------------------------------------------------
+
+	t_element * write_prepare() {
+		unsigned int rdwr = m_rdwr.load(mo_acquire);
+		unsigned int rd,wr;
+		for(;;) {
+			rd = (rdwr>>16) & 0xFFFF;
+			wr = rdwr & 0xFFFF;
+
+			if ( wr == ((rd + t_size)&0xFFFF) ) // full
+				return NULL;
+
+			if ( m_rdwr.compare_exchange_weak(rdwr,(rd<<16) | ((wr+1)&0xFFFF),mo_acq_rel) )
+				break;
+			else
+				thrd_yield();
+		}
+
+		// (*1)
+		rl::backoff bo;
+		while ( (m_read.load(mo_acquire) & 0xFFFF) != rd ) {
+			thrd_yield();
+		}
+
+		t_element * p = & ( m_array[ wr % t_size ] );
+
+		return p;
+	}
+
+	void write_publish()
+	{
+		m_written.fetch_add(1,mo_relaxed);
+	}
+
+	//-----------------------------------------------------
+
+
+};