Coverage Report

Created: 2018-08-19 14:04

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/tools/polly/lib/External/isl/isl_tarjan.c
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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)
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901
{
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901
  if (!g)
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0
    return NULL;
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901
  free(g->node);
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901
  free(g->stack);
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901
  free(g->order);
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901
  free(g);
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901
  return NULL;
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901
}
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static struct isl_tarjan_graph *isl_tarjan_graph_alloc(isl_ctx *ctx, int len)
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901
{
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901
  struct isl_tarjan_graph *g;
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901
  int i;
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901
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901
  g = isl_calloc_type(ctx, struct isl_tarjan_graph);
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901
  if (!g)
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0
    return NULL;
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901
  g->len = len;
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901
  g->node = isl_alloc_array(ctx, struct isl_tarjan_node, len);
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901
  if (len && !g->node)
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0
    goto error;
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2.55k
  
for (i = 0; 901
i < len;
++i1.65k
)
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1.65k
    g->node[i].index = -1;
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901
  g->stack = isl_alloc_array(ctx, int, len);
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901
  if (len && !g->stack)
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0
    goto error;
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901
  g->order = isl_alloc_array(ctx, int, 2 * len);
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901
  if (len && !g->order)
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0
    goto error;
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901
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901
  g->sp = 0;
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901
  g->index = 0;
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901
  g->op = 0;
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901
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901
  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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901
}
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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)
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1.64k
{
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1.64k
  int j;
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1.64k
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1.64k
  g->node[i].index = g->index;
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1.64k
  g->node[i].min_index = g->index;
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1.64k
  g->node[i].on_stack = 1;
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1.64k
  g->index++;
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1.64k
  g->stack[g->sp++] = i;
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1.64k
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6.18k
  for (j = g->len - 1; j >= 0; 
--j4.53k
) {
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4.53k
    isl_bool f;
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4.53k
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4.53k
    if (j == i)
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1.64k
      continue;
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2.88k
    if (g->node[j].index >= 0 &&
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2.88k
      
(1.63k
!g->node[j].on_stack1.63k
||
80
1.63k
       
g->node[j].index > g->node[i].min_index981
))
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1.04k
      continue;
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1.83k
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1.83k
    f = follows(i, j, user);
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1.83k
    if (f < 0)
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0
      return isl_stat_error;
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1.83k
    if (!f)
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857
      continue;
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981
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981
    if (g->node[j].index < 0) {
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544
      isl_tarjan_components(g, j, follows, user);
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544
      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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544
    } else 
if (437
g->node[j].index < g->node[i].min_index437
)
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437
      g->node[i].min_index = g->node[j].index;
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981
  }
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1.64k
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1.64k
  if (g->node[i].index != g->node[i].min_index)
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439
    return isl_stat_ok;
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1.21k
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1.64k
  
do 1.21k
{
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1.64k
    j = g->stack[--g->sp];
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1.64k
    g->node[j].on_stack = 0;
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1.64k
    g->order[g->op++] = j;
104
1.64k
  } while (j != i);
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1.21k
  g->order[g->op++] = -1;
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1.21k
107
1.21k
  return isl_stat_ok;
108
1.21k
}
109
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/* Decompose the graph with "len" nodes and edges defined by "follows"
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 * 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.
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 *
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 * 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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 */
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struct isl_tarjan_graph *isl_tarjan_graph_init(isl_ctx *ctx, int len,
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  isl_bool (*follows)(int i, int j, void *user), void *user)
121
865
{
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865
  int i;
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865
  struct isl_tarjan_graph *g = NULL;
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865
125
865
  g = isl_tarjan_graph_alloc(ctx, len);
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865
  if (!g)
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0
    return NULL;
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2.42k
  
for (i = len - 1; 865
i >= 0;
--i1.56k
) {
129
1.56k
    if (g->node[i].index >= 0)
130
494
      continue;
131
1.06k
    if (isl_tarjan_components(g, i, follows, user) < 0)
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0
      return isl_tarjan_graph_free(g);
133
1.06k
  }
134
865
135
865
  return g;
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865
}
137
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/* Decompose the graph with "len" nodes and edges defined by "follows"
139
 * into the strongly connected component (SCC) that contains "node"
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 * as well as all SCCs that are followed by this SCC.
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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.
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 *
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 * The SCC containing "node" will appear as the last component
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 * in g->order.
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 */
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struct isl_tarjan_graph *isl_tarjan_graph_component(isl_ctx *ctx, int len,
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  int node, isl_bool (*follows)(int i, int j, void *user), void *user)
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36
{
150
36
  struct isl_tarjan_graph *g;
151
36
152
36
  g = isl_tarjan_graph_alloc(ctx, len);
153
36
  if (!g)
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0
    return NULL;
155
36
  if (isl_tarjan_components(g, node, follows, user) < 0)
156
0
    return isl_tarjan_graph_free(g);
157
36
158
36
  return g;
159
36
}