GDB: Add eigen printer

dot_config/gdb/eigen/printers.py

@@ -0,0 +1,338 @@
+# -*- coding: utf-8 -*-
+# This file is part of Eigen, a lightweight C++ template library
+# for linear algebra.
+#
+# Copyright (C) 2009 Benjamin Schindler <[email protected]>
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Pretty printers for Eigen::Matrix
+# This is still pretty basic as the python extension to gdb is still pretty basic. 
+# It cannot handle complex eigen types and it doesn't support many of the other eigen types
+# This code supports fixed size as well as dynamic size matrices
+
+# To use it:
+#
+# * Create a directory and put the file as well as an empty __init__.py in 
+#   that directory.
+# * Create a ~/.gdbinit file, that contains the following:
+#      python
+#      import sys
+#      sys.path.insert(0, '/path/to/eigen/printer/directory')
+#      from printers import register_eigen_printers
+#      register_eigen_printers(None)
+#      end
+
+import gdb
+import re
+from bisect import bisect_left
+
+
+# Basic row/column iteration code for use with Sparse and Dense matrices
+class _MatrixEntryIterator(object):
+
+	def __init__(self, rows, cols, row_major):
+		self.rows = rows
+		self.cols = cols
+		self.currentRow = 0
+		self.currentCol = 0
+		self.rowMajor = row_major
+
+	def __iter__(self):
+		return self
+
+	def next(self):
+		return self.__next__()  # Python 2.x compatibility
+
+	def __next__(self):
+		row = self.currentRow
+		col = self.currentCol
+		if self.rowMajor == 0:
+			if self.currentCol >= self.cols:
+				raise StopIteration
+
+			self.currentRow += 1
+			if self.currentRow >= self.rows:
+				self.currentRow = 0
+				self.currentCol += 1
+		else:
+			if self.currentRow >= self.rows:
+				raise StopIteration
+
+			self.currentCol += 1
+			if self.currentCol >= self.cols:
+				self.currentCol = 0
+				self.currentRow += 1
+
+		return row, col
+
+
+class EigenMatrixPrinter:
+	"""Print Eigen Matrix or Array of some kind"""
+
+	def __init__(self, variety, val):
+		"""Extract all the necessary information"""
+
+		# Save the variety (presumably "Matrix" or "Array") for later usage
+		self.variety = variety
+
+		# The gdb extension does not support value template arguments - need to extract them by hand
+		typeinfo = val.type
+		if typeinfo.code == gdb.TYPE_CODE_REF:
+			typeinfo = typeinfo.target()
+		self.type = typeinfo.unqualified().strip_typedefs()
+		tag = self.type.tag
+		regex = re.compile('<.*>')
+		m = regex.findall(tag)[0][1:-1]
+		template_params = m.split(',')
+		template_params = [x.replace(" ", "") for x in template_params]
+
+		if template_params[1] in ['-0x00000000000000001', '-0x000000001', '-1']:
+			self.rows = val['m_storage']['m_rows']
+		else:
+			self.rows = int(template_params[1])
+
+		if template_params[2] in ['-0x00000000000000001', '-0x000000001', '-1']:
+			self.cols = val['m_storage']['m_cols']
+		else:
+			self.cols = int(template_params[2])
+
+		self.options = 0  # default value
+		if len(template_params) > 3:
+			self.options = template_params[3]
+
+		self.rowMajor = (int(self.options) & 0x1)
+
+		self.innerType = self.type.template_argument(0)
+
+		self.val = val
+
+		# Fixed size matrices have a struct as their storage, so we need to walk through this
+		self.data = self.val['m_storage']['m_data']
+		if self.data.type.code == gdb.TYPE_CODE_STRUCT:
+			self.data = self.data['array']
+			self.data = self.data.cast(self.innerType.pointer())
+
+	class _Iterator(_MatrixEntryIterator):
+		def __init__(self, rows, cols, data_ptr, row_major):
+			super(EigenMatrixPrinter._Iterator, self).__init__(rows, cols, row_major)
+
+			self.dataPtr = data_ptr
+
+		def __next__(self):
+			row, col = super(EigenMatrixPrinter._Iterator, self).__next__()
+
+			item = self.dataPtr.dereference()
+			self.dataPtr += 1
+			if self.cols == 1:  # if it's a column vector
+				return '[%d]' % (row,), item
+			elif self.rows == 1:  # if it's a row vector
+				return '[%d]' % (col,), item
+			return '[%d,%d]' % (row, col), item
+
+	def children(self):
+		return self._Iterator(self.rows, self.cols, self.data, self.rowMajor)
+
+	def to_string(self):
+		return "Eigen::%s<%s,%d,%d,%s> (data ptr: %s)" % (
+			self.variety, self.innerType, self.rows, self.cols,
+			"RowMajor" if self.rowMajor else "ColMajor", self.data)
+
+
+class EigenSparseMatrixPrinter:
+	"""Print an Eigen SparseMatrix"""
+
+	def __init__(self, val):
+		"""Extract all the necessary information"""
+
+		typeinfo = val.type
+		if typeinfo.code == gdb.TYPE_CODE_REF:
+			typeinfo = typeinfo.target()
+		self.type = typeinfo.unqualified().strip_typedefs()
+		tag = self.type.tag
+		regex = re.compile('<.*>')
+		m = regex.findall(tag)[0][1:-1]
+		template_params = m.split(',')
+		template_params = [x.replace(" ", "") for x in template_params]
+
+		self.options = 0
+		if len(template_params) > 1:
+			self.options = template_params[1]
+
+		self.rowMajor = (int(self.options) & 0x1)
+
+		self.innerType = self.type.template_argument(0)
+
+		self.val = val
+
+		self.data = self.val['m_data']
+		self.data = self.data.cast(self.innerType.pointer())
+
+	class _Iterator(_MatrixEntryIterator):
+		def __init__(self, rows, cols, val, row_major):
+			super(EigenSparseMatrixPrinter._Iterator, self).__init__(rows, cols, row_major)
+
+			self.val = val
+
+		def __next__(self):
+			row, col = super(EigenSparseMatrixPrinter._Iterator, self).__next__()
+
+			# repeat calculations from SparseMatrix.h:
+			outer = row if self.rowMajor else col
+			inner = col if self.rowMajor else row
+			start = self.val['m_outerIndex'][outer]
+			end = (
+				(start + self.val['m_innerNonZeros'][outer])
+				if self.val['m_innerNonZeros'] else self.val['m_outerIndex'][outer+1]
+			)
+
+			# and from CompressedStorage.h:
+			data = self.val['m_data']
+			if start >= end:
+				item = 0
+			elif (end > start) and (inner == data['m_indices'][end-1]):
+				item = data['m_values'][end-1]
+			else:
+				# create Python index list from the target range within m_indices
+				indices = [data['m_indices'][x] for x in range(int(start), int(end)-1)]
+				# find the index with binary search
+				idx = int(start) + bisect_left(indices, inner)
+				if idx < end and data['m_indices'][idx] == inner:
+					item = data['m_values'][idx]
+				else:
+					item = 0
+
+			return '[%d,%d]' % (row, col), item
+
+	def children(self):
+		if self.data:
+			return self._Iterator(self.rows(), self.cols(), self.val, self.rowMajor)
+
+		return iter([])   # empty matrix, for now
+
+	def rows(self):
+		return self.val['m_outerSize'] if self.rowMajor else self.val['m_innerSize']
+
+	def cols(self):
+		return self.val['m_innerSize'] if self.rowMajor else self.val['m_outerSize']
+
+	def to_string(self):
+
+		if self.data:
+			status = ("not compressed" if self.val['m_innerNonZeros'] else "compressed")
+		else:
+			status = "empty"
+		dimensions = "%d x %d" % (self.rows(), self.cols())
+		layout = "row" if self.rowMajor else "column"
+
+		return "Eigen::SparseMatrix<%s>, %s, %s major, %s" % (
+			self.innerType, dimensions, layout, status)
+
+
+class EigenQuaternionPrinter:
+	"""Print an Eigen Quaternion"""
+
+	def __init__(self, val):
+		"""Extract all the necessary information"""
+		# The gdb extension does not support value template arguments - need to extract them by hand
+		typeinfo = val.type
+		if typeinfo.code == gdb.TYPE_CODE_REF:
+			typeinfo = typeinfo.target()
+		self.type = typeinfo.unqualified().strip_typedefs()
+		self.innerType = self.type.template_argument(0)
+		self.val = val
+
+		# Quaternions have a struct as their storage, so we need to walk through this
+		self.data = self.val['m_coeffs']['m_storage']['m_data']['array']
+		self.data = self.data.cast(self.innerType.pointer())
+
+	class _Iterator:
+		def __init__(self, data_ptr):
+			self.dataPtr = data_ptr
+			self.currentElement = 0
+			self.elementNames = ['x', 'y', 'z', 'w']
+
+		def __iter__(self):
+			return self
+
+		def next(self):
+			return self.__next__()  # Python 2.x compatibility
+
+		def __next__(self):
+			element = self.currentElement
+
+			if self.currentElement >= 4:  # there are 4 elements in a quaternion
+				raise StopIteration
+
+			self.currentElement += 1
+
+			item = self.dataPtr.dereference()
+			self.dataPtr += 1
+			return '[%s]' % (self.elementNames[element],), item
+
+	def children(self):
+		return self._Iterator(self.data)
+
+	def to_string(self):
+		return "Eigen::Quaternion<%s> (data ptr: %s)" % (self.innerType, self.data)
+
+
+def cast_eigen_block_to_matrix(val):
+	# Get the type of the variable (and convert to a string)
+	# Example: 'const Eigen::Block<Eigen::Block<Eigen::Matrix<double, -1, -1, 0, -1, -1>, -1, -1, false> const, -1, -1, false>'
+	val_type = str(val.type)
+
+	# Extract the Eigen::Matrix type from the Block:
+	# From the previous example: Eigen::Matrix<double, -1, -1, 0, -1, -1>
+	begin = val_type.find('Eigen::Matrix<')
+	end = val_type.find('>', begin) + 1
+
+	# Convert the Eigen::Block to an Eigen::Matrix
+	return val.cast(gdb.lookup_type(val_type[begin:end]))
+
+
+def build_eigen_dictionary():
+	pretty_printers_dict[re.compile('^Eigen::Quaternion<.*>$')] = lambda val: EigenQuaternionPrinter(val)
+	pretty_printers_dict[re.compile('^Eigen::Matrix<.*>$')] = lambda val: EigenMatrixPrinter("Matrix", val)
+	pretty_printers_dict[re.compile('^Eigen::Block<.*>$')] =\
+		lambda val: EigenMatrixPrinter("Matrix", cast_eigen_block_to_matrix(val))
+	pretty_printers_dict[re.compile('^Eigen::VectorBlock<.*>$')] =\
+		lambda val: EigenMatrixPrinter("Matrix", cast_eigen_block_to_matrix(val))
+	pretty_printers_dict[re.compile('^Eigen::SparseMatrix<.*>$')] = lambda val: EigenSparseMatrixPrinter(val)
+	pretty_printers_dict[re.compile('^Eigen::Array<.*>$')] = lambda val: EigenMatrixPrinter("Array",  val)
+
+
+def register_eigen_printers(obj):
+	"""Register eigen pretty-printers with objfile Obj"""
+
+	if obj is None:
+		obj = gdb
+	obj.pretty_printers.append(lookup_function)
+
+
+def lookup_function(val):
+	"""Look-up and return a pretty-printer that can print val."""
+
+	typeinfo = val.type
+
+	if typeinfo.code == gdb.TYPE_CODE_REF:
+		typeinfo = typeinfo.target()
+
+	typeinfo = typeinfo.unqualified().strip_typedefs()
+
+	typename = typeinfo.tag
+	if typename is None:
+		return None
+
+	for function in pretty_printers_dict:
+		if function.search(typename):
+			return pretty_printers_dict[function](val)
+
+	return None
+
+
+pretty_printers_dict = {}
+
+build_eigen_dictionary()

dot_config/gdb/eigen/readme.org

@@ -0,0 +1,6 @@
+* About
+These are scripts and other pretty-printers for making GDB more
+tractable.
+
+** Eigen
+The `printers.py` is sourced from the [[https://gitlab.com/libeigen/eigen/-/blob/master/debug/gdb/printers.py][Eigen GitLab]] repository.

dot_gdbinit

@@ -0,0 +1,9 @@
+python
+import sys
+import os
+# For eigen
+eigprint = f"{os.environ['HOME']}/.config/gdb/eigen"
+sys.path.insert(0, eigprint)
+from printers import register_eigen_printers
+register_eigen_printers(None)
+end