From 3650294e512d48f2f2bb1bfdd867f672b7dc62dd Mon Sep 17 00:00:00 2001
From: Keith Rothman <537074+litghost@users.noreply.github.com>
Date: Tue, 23 Feb 2021 15:36:51 -0800
Subject: Add dynamic bitarray to common library.

Signed-off-by: Keith Rothman <537074+litghost@users.noreply.github.com>
---
 common/dynamic_bitarray.h | 82 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 common/dynamic_bitarray.h

(limited to 'common')

diff --git a/common/dynamic_bitarray.h b/common/dynamic_bitarray.h
new file mode 100644
index 00000000..7a7b2bf9
--- /dev/null
+++ b/common/dynamic_bitarray.h
@@ -0,0 +1,82 @@
+/*
+ *  nextpnr -- Next Generation Place and Route
+ *
+ *  Copyright (C) 2021  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.
+ *
+ */
+
+#include <cstdint>
+#include <limits>
+#include <vector>
+
+// This class implements a simple dynamic bitarray, backed by some resizable
+// random access storage.  The default is to use a std::vector<uint8_t>.
+
+#ifndef DYNAMIC_BITARRAY_H
+#define DYNAMIC_BITARRAY_H
+
+namespace nextpnr {
+
+template <typename Storage = std::vector<uint8_t>> class DynamicBitarray
+{
+  public:
+    static_assert(!std::numeric_limits<typename Storage::value_type>::is_signed, "Storage must be unsigned!");
+
+    void fill(bool value)
+    {
+        std::fill(storage.begin(), storage.end(), value ? std::numeric_limits<typename Storage::value_type>::max() : 0);
+    }
+
+    constexpr size_t bits_per_value() const
+    {
+        return sizeof(typename Storage::value_type) * std::numeric_limits<typename Storage::value_type>::digits;
+    }
+
+    bool get(size_t bit) const
+    {
+        size_t element_index = bit / bits_per_value();
+        size_t bit_offset = bit % bits_per_value();
+
+        auto element = storage.at(element_index);
+        return (element & (1 << bit_offset)) != 0;
+    }
+
+    void set(size_t bit, bool value)
+    {
+        size_t element_index = bit / bits_per_value();
+        size_t bit_offset = bit % bits_per_value();
+
+        if (value) {
+            storage.at(element_index) |= (1 << bit_offset);
+        } else {
+            storage.at(element_index) &= ~(1 << bit_offset);
+        }
+    }
+
+    void resize(size_t number_bits)
+    {
+        size_t required_storage = (number_bits + bits_per_value()) / bits_per_value();
+        storage.resize(required_storage);
+    }
+
+    size_t size() const { return storage.size() * bits_per_value(); }
+
+  private:
+    Storage storage;
+};
+
+}; // namespace nextpnr
+
+#endif /* DYNAMIC_BITARRAY_H */
-- 
cgit v1.2.3


From 6d193ffd8b6482cddceb5c9050e36315d99d3363 Mon Sep 17 00:00:00 2001
From: Keith Rothman <537074+litghost@users.noreply.github.com>
Date: Wed, 24 Feb 2021 08:52:26 -0800
Subject: Fix some bugs found in review.

Signed-off-by: Keith Rothman <537074+litghost@users.noreply.github.com>
---
 common/dynamic_bitarray.h | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

(limited to 'common')

diff --git a/common/dynamic_bitarray.h b/common/dynamic_bitarray.h
index 7a7b2bf9..10a85fbc 100644
--- a/common/dynamic_bitarray.h
+++ b/common/dynamic_bitarray.h
@@ -39,10 +39,7 @@ template <typename Storage = std::vector<uint8_t>> class DynamicBitarray
         std::fill(storage.begin(), storage.end(), value ? std::numeric_limits<typename Storage::value_type>::max() : 0);
     }
 
-    constexpr size_t bits_per_value() const
-    {
-        return sizeof(typename Storage::value_type) * std::numeric_limits<typename Storage::value_type>::digits;
-    }
+    constexpr size_t bits_per_value() const { return std::numeric_limits<typename Storage::value_type>::digits; }
 
     bool get(size_t bit) const
     {
@@ -67,7 +64,7 @@ template <typename Storage = std::vector<uint8_t>> class DynamicBitarray
 
     void resize(size_t number_bits)
     {
-        size_t required_storage = (number_bits + bits_per_value()) / bits_per_value();
+        size_t required_storage = (number_bits + bits_per_value() - 1) / bits_per_value();
         storage.resize(required_storage);
     }
 
-- 
cgit v1.2.3