From 597097eaef64486a8032b7a6dac2186658f0926a Mon Sep 17 00:00:00 2001
From: Martin Whitaker <icarus@martin-whitaker.me.uk>
Date: Sun, 26 Jul 2009 23:43:38 +0100
Subject: [PATCH] Fix for pr2821633.

Currently, edge event functors declared in automatically allocated
scopes that are used to detect edges on signals declared in static
scopes are unable to correctly determine edge information for the
first signal delta they receive because they do not know the old
state of the signal. This patch causes the state of static signals
received by these event functors to be recorded as static state in
the functors, so the old state of the signals can be initialised
to the correct value when a new automatic context is created.
(cherry picked from commit d7fe9c613cb08a1661465b2d59ece7d23ef600fc)
---
 vvp/event.cc | 19 ++++++++++++-------
 vvp/event.h  | 10 ++++++----
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/vvp/event.cc b/vvp/event.cc
index 7bb4aed4d..3a6f95a67 100644
--- a/vvp/event.cc
+++ b/vvp/event.cc
@@ -195,6 +195,8 @@ struct vvp_fun_edge_state_s : public waitable_state_s {
 vvp_fun_edge::vvp_fun_edge(edge_t e)
 : edge_(e)
 {
+      for (unsigned idx = 0 ;  idx < 4 ;  idx += 1)
+            bits_[idx] = BIT4_X;
 }
 
 vvp_fun_edge::~vvp_fun_edge()
@@ -220,8 +222,6 @@ bool vvp_fun_edge::recv_vec4_(vvp_net_ptr_t port, const vvp_vector4_t&bit,
 vvp_fun_edge_sa::vvp_fun_edge_sa(edge_t e)
 : vvp_fun_edge(e), threads_(0)
 {
-      for (unsigned idx = 0 ;  idx < 4 ;  idx += 1)
-            bits_[idx] = BIT4_X;
 }
 
 vvp_fun_edge_sa::~vvp_fun_edge_sa()
@@ -259,6 +259,7 @@ vvp_fun_edge_aa::~vvp_fun_edge_aa()
 void vvp_fun_edge_aa::alloc_instance(vvp_context_t context)
 {
       vvp_set_context_item(context, context_idx_, new vvp_fun_edge_state_s);
+      reset_instance(context);
 }
 
 void vvp_fun_edge_aa::reset_instance(vvp_context_t context)
@@ -268,7 +269,7 @@ void vvp_fun_edge_aa::reset_instance(vvp_context_t context)
 
       state->threads = 0;
       for (unsigned idx = 0 ;  idx < 4 ;  idx += 1)
-            state->bits[idx] = BIT4_X;
+            state->bits[idx] = bits_[idx];
 }
 
 #ifdef CHECK_WITH_VALGRIND
@@ -308,6 +309,7 @@ void vvp_fun_edge_aa::recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit,
                   recv_vec4(port, bit, context);
                   context = vvp_get_next_context(context);
             }
+            bits_[port.port()] = bit.value(0);
       }
 }
 
@@ -324,6 +326,8 @@ struct vvp_fun_anyedge_state_s : public waitable_state_s {
 
 vvp_fun_anyedge::vvp_fun_anyedge()
 {
+      for (unsigned idx = 0 ;  idx < 4 ;  idx += 1)
+	    bitsr_[idx] = 0.0;
 }
 
 vvp_fun_anyedge::~vvp_fun_anyedge()
@@ -369,8 +373,6 @@ bool vvp_fun_anyedge::recv_real_(vvp_net_ptr_t port, double bit,
 vvp_fun_anyedge_sa::vvp_fun_anyedge_sa()
 : threads_(0)
 {
-      for (unsigned idx = 0 ;  idx < 4 ;  idx += 1)
-	    bitsr_[idx] = 0.0;
 }
 
 vvp_fun_anyedge_sa::~vvp_fun_anyedge_sa()
@@ -416,6 +418,7 @@ vvp_fun_anyedge_aa::~vvp_fun_anyedge_aa()
 void vvp_fun_anyedge_aa::alloc_instance(vvp_context_t context)
 {
       vvp_set_context_item(context, context_idx_, new vvp_fun_anyedge_state_s);
+      reset_instance(context);
 }
 
 void vvp_fun_anyedge_aa::reset_instance(vvp_context_t context)
@@ -425,8 +428,8 @@ void vvp_fun_anyedge_aa::reset_instance(vvp_context_t context)
 
       state->threads = 0;
       for (unsigned idx = 0 ;  idx < 4 ;  idx += 1) {
-            state->bits[idx].set_to_x();
-	    state->bitsr[idx] = 0.0;
+            state->bits[idx] = bits_[idx];
+	    state->bitsr[idx] = bitsr_[idx];
       }
 }
 
@@ -467,6 +470,7 @@ void vvp_fun_anyedge_aa::recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit,
                   recv_vec4(port, bit, context);
                   context = vvp_get_next_context(context);
             }
+            bits_[port.port()] = bit;
       }
 }
 
@@ -487,6 +491,7 @@ void vvp_fun_anyedge_aa::recv_real(vvp_net_ptr_t port, double bit,
                   recv_real(port, bit, context);
                   context = vvp_get_next_context(context);
             }
+            bitsr_[port.port()] = bit;
       }
 }
 
diff --git a/vvp/event.h b/vvp/event.h
index 7700f4329..fd7ac81ae 100644
--- a/vvp/event.h
+++ b/vvp/event.h
@@ -141,6 +141,8 @@ class vvp_fun_edge : public vvp_net_fun_t, public waitable_hooks_s {
       bool recv_vec4_(vvp_net_ptr_t port, const vvp_vector4_t&bit,
                       vvp_bit4_t&old_bit, vthread_t&threads);
 
+      vvp_bit4_t bits_[4];
+
     private:
       edge_t edge_;
 };
@@ -165,7 +167,6 @@ class vvp_fun_edge_sa : public vvp_fun_edge {
 
     private:
       vthread_t threads_;
-      vvp_bit4_t bits_[4];
 };
 
 /*
@@ -214,6 +215,10 @@ class vvp_fun_anyedge : public vvp_net_fun_t, public waitable_hooks_s {
                       vvp_vector4_t&old_bits, vthread_t&threads);
       bool recv_real_(vvp_net_ptr_t port, double bit,
                       double&old_bits, vthread_t&threads);
+
+      vvp_vector4_t bits_[4];
+	// In case I'm a real-valued event.
+      double bitsr_[4];
 };
 
 /*
@@ -235,9 +240,6 @@ class vvp_fun_anyedge_sa : public vvp_fun_anyedge {
 
     private:
       vthread_t threads_;
-      vvp_vector4_t bits_[4];
-	// In case I'm a real-valued event.
-      double bitsr_[4];
 };
 
 /*