Coverage Report

Created: 2017-03-24 03:18

/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)
1
/*
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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
580
{
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580
  if (!g)
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0
    return NULL;
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580
  free(g->node);
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580
  free(g->stack);
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580
  free(g->order);
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580
  free(g);
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580
  return NULL;
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580
}
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static struct isl_tarjan_graph *isl_tarjan_graph_alloc(isl_ctx *ctx, int len)
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580
{
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580
  struct isl_tarjan_graph *g;
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580
  int i;
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580
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580
  g = isl_calloc_type(ctx, struct isl_tarjan_graph);
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580
  if (!g)
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0
    return NULL;
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580
  g->len = len;
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580
  g->node = isl_alloc_array(ctx, struct isl_tarjan_node, len);
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580
  if (
len && 580
!g->node580
)
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0
    goto error;
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1.71k
  
for (i = 0; 580
i < len1.71k
;
++i1.13k
)
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1.13k
    g->node[i].index = -1;
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580
  g->stack = isl_alloc_array(ctx, int, len);
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580
  if (
len && 580
!g->stack580
)
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0
    goto error;
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580
  
g->order = 580
isl_alloc_array580
(ctx, int, 2 * len);
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580
  if (
len && 580
!g->order580
)
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0
    goto error;
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580
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580
  g->sp = 0;
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580
  g->index = 0;
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580
  g->op = 0;
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580
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580
  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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580
}
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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
1.13k
{
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1.13k
  int j;
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1.13k
67
1.13k
  g->node[i].index = g->index;
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1.13k
  g->node[i].min_index = g->index;
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1.13k
  g->node[i].on_stack = 1;
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1.13k
  g->index++;
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1.13k
  g->stack[g->sp++] = i;
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1.13k
73
4.51k
  for (j = g->len - 1; 
j >= 04.51k
;
--j3.38k
)
{3.38k
74
3.38k
    isl_bool f;
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3.38k
76
3.38k
    if (j == i)
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1.13k
      continue;
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2.24k
    
if (2.24k
g->node[j].index >= 0 &&2.24k
79
1.22k
      (!g->node[j].on_stack ||
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683
       g->node[j].index > g->node[i].min_index))
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736
      continue;
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2.24k
83
1.51k
    f = follows(i, j, user);
84
1.51k
    if (f < 0)
85
0
      return isl_stat_error;
86
1.51k
    
if (1.51k
!f1.51k
)
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756
      continue;
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1.51k
89
756
    
if (756
g->node[j].index < 0756
)
{432
90
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      isl_tarjan_components(g, j, follows, user);
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432
      if (g->node[j].min_index < g->node[i].min_index)
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4
        g->node[i].min_index = g->node[j].min_index;
93
324
    } else 
if (324
g->node[j].index < g->node[i].min_index324
)
94
324
      g->node[i].min_index = g->node[j].index;
95
756
  }
96
1.13k
97
1.13k
  
if (1.13k
g->node[i].index != g->node[i].min_index1.13k
)
98
328
    return isl_stat_ok;
99
1.13k
100
1.13k
  
do 805
{1.13k
101
1.13k
    j = g->stack[--g->sp];
102
1.13k
    g->node[j].on_stack = 0;
103
1.13k
    g->order[g->op++] = j;
104
1.13k
  } while (j != i);
105
805
  g->order[g->op++] = -1;
106
805
107
805
  return isl_stat_ok;
108
1.13k
}
109
110
/* 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
116
 * (i.e., follows(i, j, user) returns 1), then SCC a will appear after SCC b
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 * in the result.
118
 */
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
557
{
122
557
  int i;
123
557
  struct isl_tarjan_graph *g = NULL;
124
557
125
557
  g = isl_tarjan_graph_alloc(ctx, len);
126
557
  if (!g)
127
0
    return NULL;
128
1.62k
  
for (i = len - 1; 557
i >= 01.62k
;
--i1.07k
)
{1.07k
129
1.07k
    if (g->node[i].index >= 0)
130
394
      continue;
131
678
    
if (678
isl_tarjan_components(g, i, follows, user) < 0678
)
132
0
      return isl_tarjan_graph_free(g);
133
678
  }
134
557
135
557
  return g;
136
557
}
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
145
 * in g->order.
146
 */
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
23
{
150
23
  struct isl_tarjan_graph *g;
151
23
152
23
  g = isl_tarjan_graph_alloc(ctx, len);
153
23
  if (!g)
154
0
    return NULL;
155
23
  
if (23
isl_tarjan_components(g, node, follows, user) < 023
)
156
0
    return isl_tarjan_graph_free(g);
157
23
158
23
  return g;
159
23
}