add bit-matrix, avoid flattening and/or after bit-blasting, split pdd_grobner into solver/simplifier, add xlin, add smtfd option for incremental mode logic

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/math/simplex/bit_matrix.cpp

@@ -0,0 +1,92 @@
+/*++
+Copyright (c) 2020 Microsoft Corporation
+
+Module Name:
+
+    bit_matrix.cpp    
+    
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2020-01-1
+
+Notes:
+
+--*/
+
+#include "math/simplex/bit_matrix.h"
+
+
+bit_matrix::col_iterator bit_matrix::row::begin() const { 
+    return bit_matrix::col_iterator(*this, true); 
+}
+
+bit_matrix::col_iterator bit_matrix::row::end() const { 
+    return bit_matrix::col_iterator(*this, false); 
+}
+
+void bit_matrix::col_iterator::next() {
+    ++m_column;
+    while (m_column < r.m.m_num_columns && !r[m_column]) {
+        while ((m_column % 64) == 0 && m_column + 64 < r.m.m_num_columns && !r.r[m_column >> 6]) {
+            m_column += 64;
+        }
+        ++m_column;
+    }
+}
+
+bool bit_matrix::row::operator[](unsigned i) const {
+    SASSERT((i >> 6) < m.m_num_chunks);
+    return (r[i >> 6] & (1ull << static_cast<uint64_t>(i & 63))) != 0;
+}
+
+
+std::ostream& bit_matrix::row::display(std::ostream& out) const {
+    for (unsigned i = 0; i < m.m_num_columns; ++i) {
+        out << ((*this)[i]?"1":"0");
+    }
+    return out << "\n";
+}
+
+void bit_matrix::reset(unsigned num_columns) {
+    m_region.reset();
+    m_num_columns = num_columns;
+    m_num_chunks = (num_columns + 63)/64;
+}
+                
+bit_matrix::row bit_matrix::add_row() {
+    uint64_t* r = new (m_region) uint64_t[m_num_chunks];
+    m_rows.push_back(r);
+    memset(r, 0, sizeof(uint64_t)*m_num_chunks);
+    return row(*this, r);
+}
+
+bit_matrix::row& bit_matrix::row::operator+=(row const& other) {
+    for (unsigned i = 0; i < m.m_num_chunks; ++i) {
+        r[i] ^= other.r[i];
+    }
+    return *this;
+}
+
+void bit_matrix::solve() {
+    basic_solve();
+}
+
+void bit_matrix::basic_solve() {
+    for (row& r : *this) {
+        auto ci = r.begin();
+        if (ci != r.end()) {
+            unsigned c = *ci;
+            for (row& r2 : *this) {
+                if (r2 != r && r2[c]) r2 += r;
+            }
+        }        
+    }
+}
+
+std::ostream& bit_matrix::display(std::ostream& out) {
+    for (row& r : *this) {
+        out << r;
+    }
+    return out;
+}
+