Coverage Report

Created: 2017-10-03 07:32

/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
634
{
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634
  if (!g)
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0
    return NULL;
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634
  free(g->node);
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634
  free(g->stack);
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634
  free(g->order);
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634
  free(g);
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634
  return NULL;
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634
}
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static struct isl_tarjan_graph *isl_tarjan_graph_alloc(isl_ctx *ctx, int len)
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634
{
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  struct isl_tarjan_graph *g;
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  int i;
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634
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634
  g = isl_calloc_type(ctx, struct isl_tarjan_graph);
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634
  if (!g)
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0
    return NULL;
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634
  g->len = len;
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634
  g->node = isl_alloc_array(ctx, struct isl_tarjan_node, len);
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634
  if (
len && 634
!g->node634
)
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0
    goto error;
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1.89k
  
for (i = 0; 634
i < len1.89k
;
++i1.26k
)
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1.26k
    g->node[i].index = -1;
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634
  g->stack = isl_alloc_array(ctx, int, len);
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634
  if (
len && 634
!g->stack634
)
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0
    goto error;
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634
  
g->order = 634
isl_alloc_array634
(ctx, int, 2 * len);
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634
  if (
len && 634
!g->order634
)
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0
    goto error;
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634
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634
  g->sp = 0;
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634
  g->index = 0;
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634
  g->op = 0;
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634
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634
  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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634
}
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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
1.25k
{
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1.25k
  int j;
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1.25k
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1.25k
  g->node[i].index = g->index;
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1.25k
  g->node[i].min_index = g->index;
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1.25k
  g->node[i].on_stack = 1;
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1.25k
  g->index++;
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1.25k
  g->stack[g->sp++] = i;
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1.25k
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4.91k
  for (j = g->len - 1; 
j >= 04.91k
;
--j3.66k
) {
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3.66k
    isl_bool f;
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3.66k
76
3.66k
    if (j == i)
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1.25k
      continue;
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2.40k
    
if (2.40k
g->node[j].index >= 0 &&
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1.30k
      (!g->node[j].on_stack ||
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689
       g->node[j].index > g->node[i].min_index))
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818
      continue;
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1.59k
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1.59k
    f = follows(i, j, user);
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1.59k
    if (f < 0)
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0
      return isl_stat_error;
86
1.59k
    
if (1.59k
!f1.59k
)
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797
      continue;
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793
89
793
    
if (793
g->node[j].index < 0793
) {
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443
      isl_tarjan_components(g, j, follows, user);
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443
      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;
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793
    } else 
if (350
g->node[j].index < g->node[i].min_index350
)
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350
      g->node[i].min_index = g->node[j].index;
95
3.66k
  }
96
1.25k
97
1.25k
  
if (1.25k
g->node[i].index != g->node[i].min_index1.25k
)
98
352
    return isl_stat_ok;
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903
100
903
  
do 903
{
101
1.25k
    j = g->stack[--g->sp];
102
1.25k
    g->node[j].on_stack = 0;
103
1.25k
    g->order[g->op++] = j;
104
1.25k
  } while (j != i);
105
1.25k
  g->order[g->op++] = -1;
106
1.25k
107
1.25k
  return isl_stat_ok;
108
1.25k
}
109
110
/* Decompose the graph with "len" nodes and edges defined by "follows"
111
 * into strongly connected components (SCCs).
112
 * follows(i, j, user) should return 1 if "i" follows "j" and 0 otherwise.
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 * It should return -1 on error.
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 *
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
611
{
122
611
  int i;
123
611
  struct isl_tarjan_graph *g = NULL;
124
611
125
611
  g = isl_tarjan_graph_alloc(ctx, len);
126
611
  if (!g)
127
0
    return NULL;
128
1.80k
  
for (i = len - 1; 611
i >= 01.80k
;
--i1.19k
) {
129
1.19k
    if (g->node[i].index >= 0)
130
406
      continue;
131
789
    
if (789
isl_tarjan_components(g, i, follows, user) < 0789
)
132
0
      return isl_tarjan_graph_free(g);
133
1.19k
  }
134
611
135
611
  return g;
136
611
}
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
}