Working on standing up initial constraints system.

Signed-off-by: Keith Rothman <537074+litghost@users.noreply.github.com>

1 files changed, 109 insertions, 0 deletions

diff --git a/common/constraints.impl.h b/common/constraints.impl.h
new file mode 100644
index 00000000..9c978411
--- /dev/null
+++ b/common/constraints.impl.h
@@ -0,0 +1,109 @@
+/*
+ *  nextpnr -- Next Generation Place and Route
+ *
+ *  Copyright (C) 2021  The SymbiFlow Authors.
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#ifndef CONSTRAINTS_IMPL_H
+#define CONSTRAINTS_IMPL_H
+
+#include "exclusive_state_groups.impl.h"
+
+NEXTPNR_NAMESPACE_BEGIN
+
+template <size_t StateCount, typename StateType, typename CountType>
+template <typename ConstraintRange>
+void Constraints<StateCount, StateType, CountType>::bindBel(TagState *tags, const ConstraintRange constraints)
+{
+    for (const auto &constraint : constraints) {
+        switch (constraint.constraint_type()) {
+        case CONSTRAINT_TAG_IMPLIES:
+            tags[constraint.tag()].add_implies(constraint.state());
+            break;
+        case CONSTRAINT_TAG_REQUIRES:
+            break;
+        default:
+            NPNR_ASSERT(false);
+        }
+    }
+}
+
+template <size_t StateCount, typename StateType, typename CountType>
+template <typename ConstraintRange>
+void Constraints<StateCount, StateType, CountType>::unbindBel(TagState *tags, const ConstraintRange constraints)
+{
+    for (const auto &constraint : constraints) {
+        switch (constraint.constraint_type()) {
+        case CONSTRAINT_TAG_IMPLIES:
+            tags[constraint.tag()].remove_implies(constraint.state());
+            break;
+        case CONSTRAINT_TAG_REQUIRES:
+            break;
+        default:
+            NPNR_ASSERT(false);
+        }
+    }
+}
+
+template <size_t StateCount, typename StateType, typename CountType>
+template <typename ConstraintRange>
+bool Constraints<StateCount, StateType, CountType>::isValidBelForCellType(const Context *ctx, uint32_t prototype,
+                                                                          const TagState *tags,
+                                                                          const ConstraintRange constraints,
+                                                                          IdString object, IdString cell, BelId bel,
+                                                                          bool explain_constraints) const
+{
+    if (explain_constraints) {
+        auto &state_definition = definitions.at(prototype);
+        for (const auto &constraint : constraints) {
+            switch (constraint.constraint_type()) {
+            case CONSTRAINT_TAG_IMPLIES:
+                tags[constraint.tag()].explain_implies(ctx, object, cell, state_definition.at(constraint.tag()), bel,
+                                                       constraint.state());
+                break;
+            case CONSTRAINT_TAG_REQUIRES:
+                tags[constraint.tag()].explain_requires(ctx, object, cell, state_definition.at(constraint.tag()), bel,
+                                                        constraint.states());
+                break;
+            default:
+                NPNR_ASSERT(false);
+            }
+        }
+    }
+
+    for (const auto &constraint : constraints) {
+        switch (constraint.constraint_type()) {
+        case CONSTRAINT_TAG_IMPLIES:
+            if (!tags[constraint.tag()].check_implies(constraint.state())) {
+                return false;
+            }
+            break;
+        case CONSTRAINT_TAG_REQUIRES:
+            if (!tags[constraint.tag()].requires(constraint.states())) {
+                return false;
+            }
+            break;
+        default:
+            NPNR_ASSERT(false);
+        }
+    }
+
+    return true;
+}
+
+NEXTPNR_NAMESPACE_END
+
+#endif