# Utility class for dump basic block and SSA output to dot files
class BlockDebug
	# The output file
	var file: FileWriter

	# Dump all the hierarchy of BasicBlock from `block` to the leaves
	fun dump(block: BasicBlock)
	do
		# Write the basic blocks hierarchy in output file
		file.write("digraph basic_blocks\n\{\n")
		var i = 0
		file.write(print_block(block, i))
		file.write("\n\}")

		file.close
	end

	# Print all the block recursively from `block` to the leaves
	# *`block` The root BasicBlock
	# *`i` Used for the recursion
	private fun print_block(block: BasicBlock, i: Int): String
	do
		# Precise the type and location of the begin and end of current block
		var s = "block{block.hash.to_s} [shape=record, label="+"\"\{"
		s += "block" + block.to_s.escape_to_dot
		s += "|\{" + block.first.location.file.filename.to_s + block.first.location.line_start.to_s
		s += " | " + block.first.to_s.escape_to_dot

		# Print phi-functions if any
		for phi in block.phi_functions do
			s += " | " + phi.to_s.escape_to_dot + " "
		end

		s += "}|\{" + block.last.location.file.filename.to_s + block.last.location.line_start.to_s
		s += " | " + block.last.to_s.escape_to_dot + "}}\"];"+ "\n"

		i += 1
		block.treated_debug = true

		for b in block.successors do
			# Print edges to successors
			s += "block{block.hash.to_s} -> " + " block{b.hash.to_s};\n"

			# Recursively print child blocks
			if not b.treated_debug then s += print_block(b, i)
		end

		return s
	end
end