mirror of https://github.com/VLSIDA/OpenRAM.git
86 lines
2.9 KiB
Python
86 lines
2.9 KiB
Python
import os, copy
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from collections import defaultdict
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import gdsMill
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import tech
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import math
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import globals
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import debug
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from vector import vector
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from pin_layout import pin_layout
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class timing_graph():
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"""Implements a directed graph
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Nodes are currently just Strings.
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"""
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def __init__(self):
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self.graph = defaultdict(set)
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self.all_paths = []
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def add_edge(self, src_node, dest_node):
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"""Adds edge to graph. Nodes added as well if they do not exist."""
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src_node = src_node.lower()
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dest_node = dest_node.lower()
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self.graph[src_node].add(dest_node)
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def add_node(self, node):
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"""Add node to graph with no edges"""
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node = node.lower()
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if not node in self.graph:
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self.graph[node] = set()
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def remove_edges(self, node):
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"""Helper function to remove edges, useful for removing vdd/gnd"""
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node = node.lower()
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self.graph[node] = set()
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def get_all_paths(self, src_node, dest_node, rmv_rail_nodes=True):
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"""Traverse all paths from source to destination"""
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src_node = src_node.lower()
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dest_node = dest_node.lower()
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#Remove vdd and gnd by default
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#Will require edits if separate supplies are implemented.
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if rmv_rail_nodes:
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#Names are also assumed.
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self.remove_edges('vdd')
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self.remove_edges('gnd')
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# Mark all the vertices as not visited
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visited = set()
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# Create an array to store paths
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path = []
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self.all_paths = []
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# Call the recursive helper function to print all paths
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self.get_all_paths_util(src_node, dest_node, visited, path)
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debug.info(2, "Paths found={}".format(len(self.all_paths)))
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return self.all_paths
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def get_all_paths_util(self, cur_node, dest_node, visited, path):
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"""Recursive function to find all paths in a Depth First Search manner"""
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# Mark the current node as visited and store in path
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visited.add(cur_node)
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path.append(cur_node)
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# If current vertex is same as destination, then print
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# current path[]
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if cur_node == dest_node:
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self.all_paths.append(copy.deepcopy(path))
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else:
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# If current vertex is not destination
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#Recur for all the vertices adjacent to this vertex
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for node in self.graph[cur_node]:
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if node not in visited:
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self.get_all_paths_util(node, dest_node, visited, path)
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# Remove current vertex from path[] and mark it as unvisited
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path.pop()
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visited.remove(cur_node)
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def __str__(self):
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""" override print function output """
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return "Nodes: {}\nEdges:{} ".format(list(self.graph), self.graph) |