ASSIGN transfer data to scheduler efficiently/permalloc vvp_net_t objects.

The vvp_net_t objects are never deleted, so overload the new operator
to do a more space efficient permanent allocation.

The %assign/v instruction copied the vvp_vector4_t object needlessly
on its way to the scheduler. Eliminate that duplication.(cherry picked from commit d0f303463d)

vvp/main.cc

@@ -279,9 +279,11 @@ int main(int argc, char*argv[])
 	    vpi_mcd_printf(1, "           %8lu bufif\n",  count_functors_bufif);
 	    vpi_mcd_printf(1, "           %8lu resolv\n",count_functors_resolv);
 	    vpi_mcd_printf(1, "           %8lu signals\n", count_functors_sig);
-	    vpi_mcd_printf(1, " ... %8lu opcodes (%lu bytes)\n",
+	    vpi_mcd_printf(1, " ... %8lu opcodes (%zu bytes)\n",
 		    count_opcodes, (unsigned long)size_opcodes);
 	    vpi_mcd_printf(1, " ... %8lu nets\n",     count_vpi_nets);
+	    vpi_mcd_printf(1, " ... %8lu vvp_nets (%zu bytes)\n",
+			   count_vvp_nets, size_vvp_nets);
 	    vpi_mcd_printf(1, " ... %8lu memories\n", count_vpi_memories);
 	    vpi_mcd_printf(1, " ... %8lu scopes\n",   count_vpi_scopes);
       }
@@ -299,12 +301,11 @@ int main(int argc, char*argv[])
 	    my_getrusage(cycles+2);
 	    print_rusage(cycles+2, cycles+1);
 
-	    vpi_mcd_printf(1, "Event counts: (event pool = %lu)\n",
+	    vpi_mcd_printf(1, "Event counts:\n");
-		    count_event_pool);
+	    vpi_mcd_printf(1, "    %8lu time steps (pool=%lu)\n",
+			   count_time_events, count_time_pool);
 	    vpi_mcd_printf(1, "    %8lu thread schedule events\n",
 		    count_thread_events);
-	    vpi_mcd_printf(1, "    %8lu propagation events\n",
-		    count_prop_events);
 	    vpi_mcd_printf(1, "    %8lu assign events\n",
 		    count_assign_events);
 	    vpi_mcd_printf(1, "    %8lu other events\n",

vvp/schedule.cc

@@ -30,9 +30,9 @@
 
 unsigned long count_assign_events = 0;
 unsigned long count_gen_events = 0;
-unsigned long count_prop_events = 0;
 unsigned long count_thread_events = 0;
-unsigned long count_event_pool = 0;
+  // Count the time events (A time cell created)
+unsigned long count_time_events = 0;
 unsigned long count_time_pool = 0;
 
 
@@ -96,6 +96,12 @@ void del_thr_event_s::run_run(void)
 }
 
 struct assign_vector4_event_s  : public event_s {
+	/* The default constructor. */
+      assign_vector4_event_s() { }
+	/* A constructor that makes the val directly. */
+      assign_vector4_event_s(const vvp_vector4_t&that, unsigned adr, unsigned wid)
+      : val(that,adr,wid) { }
+
 	/* Where to do the assign. */
       vvp_net_ptr_t ptr;
 	/* Value to assign. */
@@ -485,6 +491,19 @@ void schedule_assign_vector(vvp_net_ptr_t ptr,
       schedule_event_(cur, delay, SEQ_NBASSIGN);
 }
 
+void schedule_assign_plucked_vector(vvp_net_ptr_t ptr,
+				    vvp_time64_t delay,
+				    const vvp_vector4_t&src,
+				    unsigned adr, unsigned wid)
+{
+      struct assign_vector4_event_s*cur
+	    = new struct assign_vector4_event_s(src,adr,wid);
+      cur->ptr = ptr;
+      cur->vwid = 0;
+      cur->base = 0;
+      schedule_event_(cur, delay, SEQ_NBASSIGN);
+}
+
 void schedule_assign_array_word(vvp_array_t mem,
 				unsigned word_addr,
 				unsigned off,

vvp/schedule.h

@@ -50,6 +50,10 @@ extern void schedule_assign_vector(vvp_net_ptr_t ptr,
 extern void schedule_assign_vector(vvp_net_ptr_t ptr,
 				   const vvp_vector4_t&val,
 				   vvp_time64_t  delay);
+extern void schedule_assign_plucked_vector(vvp_net_ptr_t ptr,
+					   vvp_time64_t  delay,
+					   const vvp_vector4_t&val,
+					   unsigned adr, unsigned wid);
 
 extern void schedule_assign_array_word(vvp_array_t mem,
 				       unsigned word_address,

vvp/statistics.h

@@ -27,10 +27,15 @@ extern unsigned long count_functors_logic;
 extern unsigned long count_functors_bufif;
 extern unsigned long count_functors_resolv;
 extern unsigned long count_functors_sig;
+extern unsigned long count_vvp_nets;
 extern unsigned long count_vpi_nets;
 extern unsigned long count_vpi_scopes;
 extern unsigned long count_vpi_memories;
 
+extern unsigned long count_time_events;
+extern unsigned long count_time_pool;
+
 extern size_t size_opcodes;
+extern size_t size_vvp_nets;
 
 #endif

vvp/vthread.cc

@@ -700,10 +700,15 @@ bool of_ASSIGN_V0(vthread_t thr, vvp_code_t cp)
       unsigned delay = cp->bit_idx[0];
       unsigned bit = cp->bit_idx[1];
 
-      vvp_vector4_t value = vthread_bits_to_vector(thr, bit, wid);
-
       vvp_net_ptr_t ptr (cp->net, 0);
-      schedule_assign_vector(ptr, value, delay);
+      if (bit >= 4) {
+	      // If the vector is not a synthetic one, then have the
+	      // scheduler pluck it direcly out of my vector space.
+	    schedule_assign_plucked_vector(ptr, delay, thr->bits4, bit, wid);
+      } else {
+	    vvp_vector4_t value = vthread_bits_to_vector(thr, bit, wid);
+	    schedule_assign_vector(ptr, value, delay);
+      }
 
       return true;
 }
@@ -721,10 +726,14 @@ bool of_ASSIGN_V0D(vthread_t thr, vvp_code_t cp)
       unsigned long delay = thr->words[cp->bit_idx[0]].w_int;
       unsigned bit = cp->bit_idx[1];
 
-      vvp_vector4_t value = vthread_bits_to_vector(thr, bit, wid);
-
       vvp_net_ptr_t ptr (cp->net, 0);
-      schedule_assign_vector(ptr, value, delay);
+
+      if (bit >= 4) {
+	    schedule_assign_plucked_vector(ptr, delay, thr->bits4, bit, wid);
+      } else {
+	    vvp_vector4_t value = vthread_bits_to_vector(thr, bit, wid);
+	    schedule_assign_vector(ptr, value, delay);
+      }
 
       return true;
 }

vvp/vvp_net.cc

@@ -30,6 +30,31 @@
 # include  <math.h>
 # include  <assert.h>
 
+// Allocate around 1Megbytes/chunk.
+static const size_t VVP_NET_CHUNK = 1024*1024/sizeof(vvp_net_t);
+static vvp_net_t*vvp_net_alloc_table = 0;
+static size_t vvp_net_alloc_remaining = 0;
+// For statistics, count the vvp_nets allocated and the bytes of alloc
+// chunks allocated.
+unsigned long count_vvp_nets = 0;
+size_t size_vvp_nets = 0;
+
+void* vvp_net_t::operator new (size_t size)
+{
+      assert(size == sizeof(vvp_net_t));
+      if (vvp_net_alloc_remaining == 0) {
+	    vvp_net_alloc_table = ::new vvp_net_t[VVP_NET_CHUNK];
+	    vvp_net_alloc_remaining = VVP_NET_CHUNK;
+	    size_vvp_nets += size*VVP_NET_CHUNK;
+      }
+
+      vvp_net_t*return_this = vvp_net_alloc_table;
+      vvp_net_alloc_table += 1;
+      vvp_net_alloc_remaining -= 1;
+      count_vvp_nets += 1;
+      return return_this;
+}
+      
 /* *** BIT operations *** */
 vvp_bit4_t add_with_carry(vvp_bit4_t a, vvp_bit4_t b, vvp_bit4_t&c)
 {

vvp/vvp_net.h

@@ -760,6 +760,13 @@ struct vvp_net_t {
       vvp_net_ptr_t port[4];
       vvp_net_ptr_t out;
       vvp_net_fun_t*fun;
+
+    public: // Need a better new for these objects.
+      static void* operator new(std::size_t size);
+      static void operator delete(void*); // not implemented
+    private: // not implemented
+      static void* operator new[](std::size_t size);
+      static void operator delete[](void*);
 };
 
 /*