Coverage Report

Created: 2017-06-28 17:40

/Users/buildslave/jenkins/sharedspace/clang-stage2-coverage-R@2/llvm/tools/polly/lib/External/isl/isl_tarjan.c
Line
Count
Source (jump to first uncovered line)
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/*
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 * Copyright 2010-2011 INRIA Saclay
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 * Copyright 2012      Ecole Normale Superieure
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 *
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 * Use of this software is governed by the MIT license
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 *
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 * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
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 * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
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 * 91893 Orsay, France
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 * and Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
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 */
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#include <stdlib.h>
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#include <isl/ctx.h>
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#include <isl_tarjan.h>
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struct isl_tarjan_graph *isl_tarjan_graph_free(struct isl_tarjan_graph *g)
18
606
{
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606
  if (!g)
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0
    return NULL;
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606
  free(g->node);
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606
  free(g->stack);
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606
  free(g->order);
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606
  free(g);
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606
  return NULL;
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606
}
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static struct isl_tarjan_graph *isl_tarjan_graph_alloc(isl_ctx *ctx, int len)
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606
{
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  struct isl_tarjan_graph *g;
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606
  int i;
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606
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606
  g = isl_calloc_type(ctx, struct isl_tarjan_graph);
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606
  if (!g)
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0
    return NULL;
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606
  g->len = len;
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606
  g->node = isl_alloc_array(ctx, struct isl_tarjan_node, len);
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606
  if (
len && 606
!g->node606
)
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0
    goto error;
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1.79k
  
for (i = 0; 606
i < len1.79k
;
++i1.19k
)
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1.19k
    g->node[i].index = -1;
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606
  g->stack = isl_alloc_array(ctx, int, len);
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606
  if (
len && 606
!g->stack606
)
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0
    goto error;
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606
  
g->order = 606
isl_alloc_array606
(ctx, int, 2 * len);
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606
  if (
len && 606
!g->order606
)
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0
    goto error;
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606
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606
  g->sp = 0;
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606
  g->index = 0;
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606
  g->op = 0;
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606
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606
  return g;
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0
error:
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0
  isl_tarjan_graph_free(g);
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0
  return NULL;
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606
}
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/* Perform Tarjan's algorithm for computing the strongly connected components
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 * in the graph with g->len nodes and with edges defined by "follows".
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 */
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static isl_stat isl_tarjan_components(struct isl_tarjan_graph *g, int i,
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  isl_bool (*follows)(int i, int j, void *user), void *user)
64
1.18k
{
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1.18k
  int j;
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1.18k
67
1.18k
  g->node[i].index = g->index;
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1.18k
  g->node[i].min_index = g->index;
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1.18k
  g->node[i].on_stack = 1;
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1.18k
  g->index++;
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1.18k
  g->stack[g->sp++] = i;
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1.18k
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4.67k
  for (j = g->len - 1; 
j >= 04.67k
;
--j3.49k
)
{3.49k
74
3.49k
    isl_bool f;
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3.49k
76
3.49k
    if (j == i)
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1.18k
      continue;
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2.30k
    
if (2.30k
g->node[j].index >= 0 &&2.30k
79
1.25k
      (!g->node[j].on_stack ||
80
666
       g->node[j].index > g->node[i].min_index))
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782
      continue;
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2.30k
83
1.52k
    f = follows(i, j, user);
84
1.52k
    if (f < 0)
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0
      return isl_stat_error;
86
1.52k
    
if (1.52k
!f1.52k
)
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761
      continue;
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1.52k
89
761
    
if (761
g->node[j].index < 0761
)
{426
90
426
      isl_tarjan_components(g, j, follows, user);
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426
      if (g->node[j].min_index < g->node[i].min_index)
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2
        g->node[i].min_index = g->node[j].min_index;
93
335
    } else 
if (335
g->node[j].index < g->node[i].min_index335
)
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335
      g->node[i].min_index = g->node[j].index;
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761
  }
96
1.18k
97
1.18k
  
if (1.18k
g->node[i].index != g->node[i].min_index1.18k
)
98
337
    return isl_stat_ok;
99
1.18k
100
1.18k
  
do 850
{1.18k
101
1.18k
    j = g->stack[--g->sp];
102
1.18k
    g->node[j].on_stack = 0;
103
1.18k
    g->order[g->op++] = j;
104
1.18k
  } while (j != i);
105
850
  g->order[g->op++] = -1;
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850
107
850
  return isl_stat_ok;
108
1.18k
}
109
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/* Decompose the graph with "len" nodes and edges defined by "follows"
111
 * into strongly connected components (SCCs).
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 * follows(i, j, user) should return 1 if "i" follows "j" and 0 otherwise.
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 * It should return -1 on error.
114
 *
115
 * If SCC a contains a node i that follows a node j in another SCC b
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 * (i.e., follows(i, j, user) returns 1), then SCC a will appear after SCC b
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 * in the result.
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 */
119
struct isl_tarjan_graph *isl_tarjan_graph_init(isl_ctx *ctx, int len,
120
  isl_bool (*follows)(int i, int j, void *user), void *user)
121
584
{
122
584
  int i;
123
584
  struct isl_tarjan_graph *g = NULL;
124
584
125
584
  g = isl_tarjan_graph_alloc(ctx, len);
126
584
  if (!g)
127
0
    return NULL;
128
1.71k
  
for (i = len - 1; 584
i >= 01.71k
;
--i1.12k
)
{1.12k
129
1.12k
    if (g->node[i].index >= 0)
130
390
      continue;
131
739
    
if (739
isl_tarjan_components(g, i, follows, user) < 0739
)
132
0
      return isl_tarjan_graph_free(g);
133
739
  }
134
584
135
584
  return g;
136
584
}
137
138
/* Decompose the graph with "len" nodes and edges defined by "follows"
139
 * into the strongly connected component (SCC) that contains "node"
140
 * as well as all SCCs that are followed by this SCC.
141
 * follows(i, j, user) should return 1 if "i" follows "j" and 0 otherwise.
142
 * It should return -1 on error.
143
 *
144
 * The SCC containing "node" will appear as the last component
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 * in g->order.
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 */
147
struct isl_tarjan_graph *isl_tarjan_graph_component(isl_ctx *ctx, int len,
148
  int node, isl_bool (*follows)(int i, int j, void *user), void *user)
149
22
{
150
22
  struct isl_tarjan_graph *g;
151
22
152
22
  g = isl_tarjan_graph_alloc(ctx, len);
153
22
  if (!g)
154
0
    return NULL;
155
22
  
if (22
isl_tarjan_components(g, node, follows, user) < 022
)
156
0
    return isl_tarjan_graph_free(g);
157
22
158
22
  return g;
159
22
}