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GCC Code Coverage Report

Directory:	.		Exec	Total	Coverage
File:	src/proof/proof_node_algorithm.cpp	Lines:	85	109	78.0 %
Date:	2021-09-05	Branches:	86	204	42.2 %


/******************************************************************************
 * Top contributors (to current version):
 *   Andrew Reynolds, Haniel Barbosa
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * Implementation of proof node algorithm utilities.
 */

#include "proof/proof_node_algorithm.h"

#include "proof/proof_node.h"

namespace cvc5 {
namespace expr {

void getFreeAssumptions(ProofNode* pn, std::vector<Node>& assump)
{
  std::map<Node, std::vector<std::shared_ptr<ProofNode>>> amap;
  std::shared_ptr<ProofNode> spn = std::make_shared<ProofNode>(
      pn->getRule(), pn->getChildren(), pn->getArguments());
  getFreeAssumptionsMap(spn, amap);
  for (const std::pair<const Node, std::vector<std::shared_ptr<ProofNode>>>& p :
       amap)
  {
    assump.push_back(p.first);
  }
}

void getFreeAssumptionsMap(
    std::shared_ptr<ProofNode> pn,
    std::map<Node, std::vector<std::shared_ptr<ProofNode>>>& amap)
{
  // proof should not be cyclic
  // visited set false after preorder traversal, true after postorder traversal
  std::unordered_map<ProofNode*, bool> visited;
  std::unordered_map<ProofNode*, bool>::iterator it;
  std::vector<std::shared_ptr<ProofNode>> visit;
  std::vector<std::shared_ptr<ProofNode>> traversing;
  // Maps a bound assumption to the number of bindings it is under
  // e.g. in (SCOPE (SCOPE (ASSUME x) (x y)) (y)), y would be mapped to 2 at
  // (ASSUME x), and x would be mapped to 1.
  //
  // This map is used to track which nodes are in scope while traversing the
  // DAG. The in-scope assumptions are keys in the map. They're removed when
  // their binding count drops to zero. Let's annotate the above example to
  // serve as an illustration:
  //
  //   (SCOPE0 (SCOPE1 (ASSUME x) (x y)) (y))
  //
  // This is how the map changes during the traversal:
  //   after  previsiting SCOPE0: { y: 1 }
  //   after  previsiting SCOPE1: { y: 2, x: 1 }
  //   at                 ASSUME: { y: 2, x: 1 } (so x is in scope!)
  //   after postvisiting SCOPE1: { y: 1 }
  //   after postvisiting SCOPE2: {}
  //
  std::unordered_map<Node, uint32_t> scopeDepth;
  std::shared_ptr<ProofNode> cur;
  visit.push_back(pn);
  do
  {
    cur = visit.back();
    visit.pop_back();
    it = visited.find(cur.get());
    const std::vector<Node>& cargs = cur->getArguments();
    if (it == visited.end())
    {
      PfRule id = cur->getRule();
      if (id == PfRule::ASSUME)
      {
        visited[cur.get()] = true;
        Assert(cargs.size() == 1);
        Node f = cargs[0];
        if (!scopeDepth.count(f))
        {
          amap[f].push_back(cur);
        }
      }
      else
      {
        if (id == PfRule::SCOPE)
        {
          // mark that its arguments are bound in the current scope
          for (const Node& a : cargs)
          {
            scopeDepth[a] += 1;
          }
          // will need to unbind the variables below
        }
        // The following loop cannot be merged with the loop above because the
        // same subproof
        visited[cur.get()] = false;
        visit.push_back(cur);
        traversing.push_back(cur);
        const std::vector<std::shared_ptr<ProofNode>>& cs = cur->getChildren();
        for (const std::shared_ptr<ProofNode>& cp : cs)
        {
          if (std::find(traversing.begin(), traversing.end(), cp)
              != traversing.end())
          {
            Unhandled() << "getFreeAssumptionsMap: cyclic proof! (use "
                           "--proof-eager-checking)"
                        << std::endl;
          }
          visit.push_back(cp);
        }
      }
    }
    else if (!it->second)
    {
      Assert(!traversing.empty());
      traversing.pop_back();
      visited[cur.get()] = true;
      if (cur->getRule() == PfRule::SCOPE)
      {
        // unbind its assumptions
        for (const Node& a : cargs)
        {
          auto scopeCt = scopeDepth.find(a);
          Assert(scopeCt != scopeDepth.end());
          scopeCt->second -= 1;
          if (scopeCt->second == 0)
          {
            scopeDepth.erase(scopeCt);
          }
        }
      }
    }
  } while (!visit.empty());
}

bool containsAssumption(const ProofNode* pn,
                        std::unordered_map<const ProofNode*, bool>& caMap)
{
  std::unordered_map<const ProofNode*, bool> visited;
  std::unordered_map<const ProofNode*, bool>::iterator it;
  std::vector<const ProofNode*> visit;
  visit.push_back(pn);
  bool foundAssumption = false;
  const ProofNode* cur;
  while (!visit.empty())
  {
    cur = visit.back();
    visit.pop_back();
    // have we already computed?
    it = caMap.find(cur);
    if (it != caMap.end())
    {
      // if cached, we set found assumption to true if applicable and continue
      if (it->second)
      {
        foundAssumption = true;
      }
      continue;
    }
    it = visited.find(cur);
    if (it == visited.end())
    {
      PfRule r = cur->getRule();
      if (r == PfRule::ASSUME)
      {
        visited[cur] = true;
        caMap[cur] = true;
        foundAssumption = true;
      }
      else if (!foundAssumption)
      {
        // if we haven't found an assumption yet, recurse. Otherwise, we will
        // not bother computing whether this subproof contains an assumption
        // since we know its parent already contains one by another child.
        visited[cur] = false;
        visit.push_back(cur);
        const std::vector<std::shared_ptr<ProofNode>>& children =
            cur->getChildren();
        for (const std::shared_ptr<ProofNode>& cp : children)
        {
          visit.push_back(cp.get());
        }
      }
    }
    else if (!it->second)
    {
      visited[cur] = true;
      // we contain an assumption if we've found an assumption in a child
      caMap[cur] = foundAssumption;
    }
  }
  return caMap[cur];
}

bool containsAssumption(const ProofNode* pn)
{
  std::unordered_map<const ProofNode*, bool> caMap;
  return containsAssumption(pn, caMap);
}

bool containsSubproof(ProofNode* pn, ProofNode* pnc)
{
  std::unordered_set<const ProofNode*> visited;
  return containsSubproof(pn, pnc, visited);
}

bool containsSubproof(ProofNode* pn,
                      ProofNode* pnc,
                      std::unordered_set<const ProofNode*>& visited)
{
  std::unordered_map<const ProofNode*, bool>::iterator it;
  std::vector<const ProofNode*> visit;
  visit.push_back(pn);
  const ProofNode* cur;
  while (!visit.empty())
  {
    cur = visit.back();
    visit.pop_back();
    if (visited.find(cur) == visited.end())
    {
      visited.insert(cur);
      if (cur == pnc)
      {
        return true;
      }
      const std::vector<std::shared_ptr<ProofNode>>& children =
          cur->getChildren();
      for (const std::shared_ptr<ProofNode>& cp : children)
      {
        visit.push_back(cp.get());
      }
    }
  }
  return false;
}

}  // namespace expr
}  // namespace cvc5


Generated by: GCOVR (Version 3.2)

Line	Exec	Source
1		/******************************************************************************
2		* Top contributors (to current version):
3		* Andrew Reynolds, Haniel Barbosa
4		*
5		* This file is part of the cvc5 project.
6		*
7		* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
8		* in the top-level source directory and their institutional affiliations.
9		* All rights reserved. See the file COPYING in the top-level source
10		* directory for licensing information.
11		* ****************************************************************************
12		*
13		* Implementation of proof node algorithm utilities.
14		*/
15
16		#include "proof/proof_node_algorithm.h"
17
18		#include "proof/proof_node.h"
19
20		namespace cvc5 {
21		namespace expr {
22
23	84871	void getFreeAssumptions(ProofNode* pn, std::vector<Node>& assump)
24		{
25	169742	std::map<Node, std::vector<std::shared_ptr<ProofNode>>> amap;
26		std::shared_ptr<ProofNode> spn = std::make_shared<ProofNode>(
27	169742	pn->getRule(), pn->getChildren(), pn->getArguments());
28	84871	getFreeAssumptionsMap(spn, amap);
29	114206	for (const std::pair<const Node, std::vector<std::shared_ptr<ProofNode>>>& p :
30	84871	amap)
31		{
32	114206	assump.push_back(p.first);
33		}
34	84871	}
35
36	391632	void getFreeAssumptionsMap(
37		std::shared_ptr<ProofNode> pn,
38		std::map<Node, std::vector<std::shared_ptr<ProofNode>>>& amap)
39		{
40		// proof should not be cyclic
41		// visited set false after preorder traversal, true after postorder traversal
42	783264	std::unordered_map<ProofNode*, bool> visited;
43	391632	std::unordered_map<ProofNode*, bool>::iterator it;
44	783264	std::vector<std::shared_ptr<ProofNode>> visit;
45	783264	std::vector<std::shared_ptr<ProofNode>> traversing;
46		// Maps a bound assumption to the number of bindings it is under
47		// e.g. in (SCOPE (SCOPE (ASSUME x) (x y)) (y)), y would be mapped to 2 at
48		// (ASSUME x), and x would be mapped to 1.
49		//
50		// This map is used to track which nodes are in scope while traversing the
51		// DAG. The in-scope assumptions are keys in the map. They're removed when
52		// their binding count drops to zero. Let's annotate the above example to
53		// serve as an illustration:
54		//
55		// (SCOPE0 (SCOPE1 (ASSUME x) (x y)) (y))
56		//
57		// This is how the map changes during the traversal:
58		// after previsiting SCOPE0: { y: 1 }
59		// after previsiting SCOPE1: { y: 2, x: 1 }
60		// at ASSUME: { y: 2, x: 1 } (so x is in scope!)
61		// after postvisiting SCOPE1: { y: 1 }
62		// after postvisiting SCOPE2: {}
63		//
64	783264	std::unordered_map<Node, uint32_t> scopeDepth;
65	783264	std::shared_ptr<ProofNode> cur;
66	391632	visit.push_back(pn);
67	20414291	do
68		{
69	20805923	cur = visit.back();
70	20805923	visit.pop_back();
71	20805923	it = visited.find(cur.get());
72	20805923	const std::vector<Node>& cargs = cur->getArguments();
73	20805923	if (it == visited.end())
74		{
75	10221019	PfRule id = cur->getRule();
76	10221019	if (id == PfRule::ASSUME)
77		{
78	3874177	visited[cur.get()] = true;
79	3874177	Assert(cargs.size() == 1);
80	7748354	Node f = cargs[0];
81	3874177	if (!scopeDepth.count(f))
82		{
83	3090268	amap[f].push_back(cur);
84		}
85		}
86		else
87		{
88	6346842	if (id == PfRule::SCOPE)
89		{
90		// mark that its arguments are bound in the current scope
91	998578	for (const Node& a : cargs)
92		{
93	819849	scopeDepth[a] += 1;
94		}
95		// will need to unbind the variables below
96		}
97		// The following loop cannot be merged with the loop above because the
98		// same subproof
99	6346842	visited[cur.get()] = false;
100	6346842	visit.push_back(cur);
101	6346842	traversing.push_back(cur);
102	6346842	const std::vector<std::shared_ptr<ProofNode>>& cs = cur->getChildren();
103	20414291	for (const std::shared_ptr<ProofNode>& cp : cs)
104		{
105	42202347	if (std::find(traversing.begin(), traversing.end(), cp)
106	42202347	!= traversing.end())
107		{
108		Unhandled() << "getFreeAssumptionsMap: cyclic proof! (use "
109		"--proof-eager-checking)"
110		<< std::endl;
111		}
112	14067449	visit.push_back(cp);
113		}
114		}
115		}
116	10584904	else if (!it->second)
117		{
118	6346842	Assert(!traversing.empty());
119	6346842	traversing.pop_back();
120	6346842	visited[cur.get()] = true;
121	6346842	if (cur->getRule() == PfRule::SCOPE)
122		{
123		// unbind its assumptions
124	998578	for (const Node& a : cargs)
125		{
126	819849	auto scopeCt = scopeDepth.find(a);
127	819849	Assert(scopeCt != scopeDepth.end());
128	819849	scopeCt->second -= 1;
129	819849	if (scopeCt->second == 0)
130		{
131	749516	scopeDepth.erase(scopeCt);
132		}
133		}
134		}
135		}
136	20805923	} while (!visit.empty());
137	391632	}
138
139	2267395	bool containsAssumption(const ProofNode* pn,
140		std::unordered_map<const ProofNode*, bool>& caMap)
141		{
142	4534790	std::unordered_map<const ProofNode*, bool> visited;
143	2267395	std::unordered_map<const ProofNode*, bool>::iterator it;
144	4534790	std::vector<const ProofNode*> visit;
145	2267395	visit.push_back(pn);
146	2267395	bool foundAssumption = false;
147		const ProofNode* cur;
148	18756393	while (!visit.empty())
149		{
150	8244499	cur = visit.back();
151	8244499	visit.pop_back();
152		// have we already computed?
153	8244499	it = caMap.find(cur);
154	12216903	if (it != caMap.end())
155		{
156		// if cached, we set found assumption to true if applicable and continue
157	3972404	if (it->second)
158		{
159	2558993	foundAssumption = true;
160		}
161	3972404	continue;
162		}
163	4272095	it = visited.find(cur);
164	4272095	if (it == visited.end())
165		{
166	2267395	PfRule r = cur->getRule();
167	2267395	if (r == PfRule::ASSUME)
168		{
169	262695	visited[cur] = true;
170	262695	caMap[cur] = true;
171	262695	foundAssumption = true;
172		}
173	2004700	else if (!foundAssumption)
174		{
175		// if we haven't found an assumption yet, recurse. Otherwise, we will
176		// not bother computing whether this subproof contains an assumption
177		// since we know its parent already contains one by another child.
178	2004700	visited[cur] = false;
179	2004700	visit.push_back(cur);
180		const std::vector<std::shared_ptr<ProofNode>>& children =
181	2004700	cur->getChildren();
182	5977104	for (const std::shared_ptr<ProofNode>& cp : children)
183		{
184	3972404	visit.push_back(cp.get());
185		}
186		}
187		}
188	2004700	else if (!it->second)
189		{
190	2004700	visited[cur] = true;
191		// we contain an assumption if we've found an assumption in a child
192	2004700	caMap[cur] = foundAssumption;
193		}
194		}
195	4534790	return caMap[cur];
196		}
197
198		bool containsAssumption(const ProofNode* pn)
199		{
200		std::unordered_map<const ProofNode*, bool> caMap;
201		return containsAssumption(pn, caMap);
202		}
203
204		bool containsSubproof(ProofNode* pn, ProofNode* pnc)
205		{
206		std::unordered_set<const ProofNode*> visited;
207		return containsSubproof(pn, pnc, visited);
208		}
209
210		bool containsSubproof(ProofNode* pn,
211		ProofNode* pnc,
212		std::unordered_set<const ProofNode*>& visited)
213		{
214		std::unordered_map<const ProofNode*, bool>::iterator it;
215		std::vector<const ProofNode*> visit;
216		visit.push_back(pn);
217		const ProofNode* cur;
218		while (!visit.empty())
219		{
220		cur = visit.back();
221		visit.pop_back();
222		if (visited.find(cur) == visited.end())
223		{
224		visited.insert(cur);
225		if (cur == pnc)
226		{
227		return true;
228		}
229		const std::vector<std::shared_ptr<ProofNode>>& children =
230		cur->getChildren();
231		for (const std::shared_ptr<ProofNode>& cp : children)
232		{
233		visit.push_back(cp.get());
234		}
235		}
236		}
237		return false;
238		}
239
240		} // namespace expr
241	29505	} // namespace cvc5