A Partitioned Boolean Quadratic Programming (PBQP) based register allocator.
Contributed by Lang Hames.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56959 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PBQP.h b/lib/CodeGen/PBQP.h
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+//===---------------- PBQP.cpp --------- PBQP Solver ------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Developed by: Bernhard Scholz
+// The Univesity of Sydney
+// http://www.it.usyd.edu.au/~scholz
+//===----------------------------------------------------------------------===//
+
+// TODO:
+//
+// * Default to null costs on vector initialisation?
+// * C++-ify the rest of the solver.
+
+#ifndef LLVM_CODEGEN_PBQPSOLVER_H
+#define LLVM_CODEGEN_PBQPSOLVER_H
+
+#include <cassert>
+#include <algorithm>
+#include <functional>
+
+namespace llvm {
+
+//! \brief Floating point type to use in PBQP solver.
+typedef double PBQPNum;
+
+//! \brief PBQP Vector class.
+class PBQPVector {
+public:
+
+ //! \brief Construct a PBQP vector of the given size.
+ explicit PBQPVector(unsigned length) :
+ length(length), data(new PBQPNum[length]) {
+ std::fill(data, data + length, 0);
+ }
+
+ //! \brief Copy construct a PBQP vector.
+ PBQPVector(const PBQPVector &v) :
+ length(v.length), data(new PBQPNum[length]) {
+ std::copy(v.data, v.data + length, data);
+ }
+
+ ~PBQPVector() { delete[] data; }
+
+ //! \brief Assignment operator.
+ PBQPVector& operator=(const PBQPVector &v) {
+ delete[] data;
+ length = v.length;
+ data = new PBQPNum[length];
+ std::copy(v.data, v.data + length, data);
+ return *this;
+ }
+
+ //! \brief Return the length of the vector
+ unsigned getLength() const throw () {
+ return length;
+ }
+
+ //! \brief Element access.
+ PBQPNum& operator[](unsigned index) {
+ assert(index < length && "PBQPVector element access out of bounds.");
+ return data[index];
+ }
+
+ //! \brief Const element access.
+ const PBQPNum& operator[](unsigned index) const {
+ assert(index < length && "PBQPVector element access out of bounds.");
+ return data[index];
+ }
+
+ //! \brief Add another vector to this one.
+ PBQPVector& operator+=(const PBQPVector &v) {
+ assert(length == v.length && "PBQPVector length mismatch.");
+ std::transform(data, data + length, v.data, data, std::plus<PBQPNum>());
+ return *this;
+ }
+
+ //! \brief Subtract another vector from this one.
+ PBQPVector& operator-=(const PBQPVector &v) {
+ assert(length == v.length && "PBQPVector length mismatch.");
+ std::transform(data, data + length, v.data, data, std::minus<PBQPNum>());
+ return *this;
+ }
+
+ //! \brief Returns the index of the minimum value in this vector
+ unsigned minIndex() const {
+ return std::min_element(data, data + length) - data;
+ }
+
+private:
+ unsigned length;
+ PBQPNum *data;
+};
+
+
+//! \brief PBQP Matrix class
+class PBQPMatrix {
+public:
+
+ //! \brief Construct a PBQP Matrix with the given dimensions.
+ PBQPMatrix(unsigned rows, unsigned cols) :
+ rows(rows), cols(cols), data(new PBQPNum[rows * cols]) {
+ std::fill(data, data + (rows * cols), 0);
+ }
+
+ //! \brief Copy construct a PBQP matrix.
+ PBQPMatrix(const PBQPMatrix &m) :
+ rows(m.rows), cols(m.cols), data(new PBQPNum[rows * cols]) {
+ std::copy(m.data, m.data + (rows * cols), data);
+ }
+
+ ~PBQPMatrix() { delete[] data; }
+
+ //! \brief Assignment operator.
+ PBQPMatrix& operator=(const PBQPMatrix &m) {
+ delete[] data;
+ rows = m.rows; cols = m.cols;
+ data = new PBQPNum[rows * cols];
+ std::copy(m.data, m.data + (rows * cols), data);
+ return *this;
+ }
+
+ //! \brief Return the number of rows in this matrix.
+ unsigned getRows() const throw () { return rows; }
+
+ //! \brief Return the number of cols in this matrix.
+ unsigned getCols() const throw () { return cols; }
+
+ //! \brief Matrix element access.
+ PBQPNum* operator[](unsigned r) {
+ assert(r < rows && "Row out of bounds.");
+ return data + (r * cols);
+ }
+
+ //! \brief Matrix element access.
+ const PBQPNum* operator[](unsigned r) const {
+ assert(r < rows && "Row out of bounds.");
+ return data + (r * cols);
+ }
+
+ //! \brief Returns the given row as a vector.
+ PBQPVector getRowAsVector(unsigned r) const {
+ PBQPVector v(cols);
+ for (unsigned c = 0; c < cols; ++c)
+ v[c] = (*this)[r][c];
+ return v;
+ }
+
+ //! \brief Reset the matrix to the given value.
+ PBQPMatrix& reset(PBQPNum val = 0) {
+ std::fill(data, data + (rows * cols), val);
+ return *this;
+ }
+
+ //! \brief Set a single row of this matrix to the given value.
+ PBQPMatrix& setRow(unsigned r, PBQPNum val) {
+ assert(r < rows && "Row out of bounds.");
+ std::fill(data + (r * cols), data + ((r + 1) * cols), val);
+ return *this;
+ }
+
+ //! \brief Set a single column of this matrix to the given value.
+ PBQPMatrix& setCol(unsigned c, PBQPNum val) {
+ assert(c < cols && "Column out of bounds.");
+ for (unsigned r = 0; r < rows; ++r)
+ (*this)[r][c] = val;
+ return *this;
+ }
+
+ //! \brief Matrix transpose.
+ PBQPMatrix transpose() const {
+ PBQPMatrix m(cols, rows);
+ for (unsigned r = 0; r < rows; ++r)
+ for (unsigned c = 0; c < cols; ++c)
+ m[c][r] = (*this)[r][c];
+ return m;
+ }
+
+ //! \brief Returns the diagonal of the matrix as a vector.
+ //!
+ //! Matrix must be square.
+ PBQPVector diagonalize() const {
+ assert(rows == cols && "Attempt to diagonalize non-square matrix.");
+
+ PBQPVector v(rows);
+ for (unsigned r = 0; r < rows; ++r)
+ v[r] = (*this)[r][r];
+ return v;
+ }
+
+ //! \brief Add the given matrix to this one.
+ PBQPMatrix& operator+=(const PBQPMatrix &m) {
+ assert(rows == m.rows && cols == m.cols &&
+ "Matrix dimensions mismatch.");
+ std::transform(data, data + (rows * cols), m.data, data,
+ std::plus<PBQPNum>());
+ return *this;
+ }
+
+ //! \brief Returns the minimum of the given row
+ PBQPNum getRowMin(unsigned r) const {
+ assert(r < rows && "Row out of bounds");
+ return *std::min_element(data + (r * cols), data + ((r + 1) * cols));
+ }
+
+ //! \brief Returns the minimum of the given column
+ PBQPNum getColMin(unsigned c) const {
+ PBQPNum minElem = (*this)[0][c];
+ for (unsigned r = 1; r < rows; ++r)
+ if ((*this)[r][c] < minElem) minElem = (*this)[r][c];
+ return minElem;
+ }
+
+ //! \brief Subtracts the given scalar from the elements of the given row.
+ PBQPMatrix& subFromRow(unsigned r, PBQPNum val) {
+ assert(r < rows && "Row out of bounds");
+ std::transform(data + (r * cols), data + ((r + 1) * cols),
+ data + (r * cols),
+ std::bind2nd(std::minus<PBQPNum>(), val));
+ return *this;
+ }
+
+ //! \brief Subtracts the given scalar from the elements of the given column.
+ PBQPMatrix& subFromCol(unsigned c, PBQPNum val) {
+ for (unsigned r = 0; r < rows; ++r)
+ (*this)[r][c] -= val;
+ return *this;
+ }
+
+ //! \brief Returns true if this is a zero matrix.
+ bool isZero() const {
+ return find_if(data, data + (rows * cols),
+ std::bind2nd(std::not_equal_to<PBQPNum>(), 0)) ==
+ data + (rows * cols);
+ }
+
+private:
+ unsigned rows, cols;
+ PBQPNum *data;
+};
+
+#define EPS (1E-8)
+
+#ifndef PBQP_TYPE
+#define PBQP_TYPE
+struct pbqp;
+typedef struct pbqp pbqp;
+#endif
+
+/*****************
+ * PBQP routines *
+ *****************/
+
+/* allocate pbqp problem */
+pbqp *alloc_pbqp(int num);
+
+/* add node costs */
+void add_pbqp_nodecosts(pbqp *this_,int u, PBQPVector *costs);
+
+/* add edge mat */
+void add_pbqp_edgecosts(pbqp *this_,int u,int v,PBQPMatrix *costs);
+
+/* solve PBQP problem */
+void solve_pbqp(pbqp *this_);
+
+/* get solution of a node */
+int get_pbqp_solution(pbqp *this_,int u);
+
+/* alloc PBQP */
+pbqp *alloc_pbqp(int num);
+
+/* free PBQP */
+void free_pbqp(pbqp *this_);
+
+/* is optimal */
+bool is_pbqp_optimal(pbqp *this_);
+
+}
+#endif