aboutsummaryrefslogtreecommitdiffstats
path: root/toolchain/gcc/patches/4.7.0/000-upstream_uclibc_fix.patch
blob: 508ed853c293c563baf3402f9a374ed958a907cd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
--- a/gcc/tree-ssa-tail-merge.c (revision 185028)
+++ b/gcc/tree-ssa-tail-merge.c (working copy)
@@ -1033,7 +1033,7 @@ set_cluster (basic_block bb1, basic_bloc
    gimple_bb (s2) are members of SAME_SUCC.  */
 
 static bool
-gimple_equal_p (same_succ same_succ, gimple s1, gimple s2)
+gimple_equal_p (same_succ same_succ, gimple s1, gimple s2, bool *gvn_used)
 {
   unsigned int i;
   tree lhs1, lhs2;
@@ -1069,7 +1069,10 @@ gimple_equal_p (same_succ same_succ, gim
 	  if (operand_equal_p (t1, t2, 0))
 	    continue;
 	  if (gvn_uses_equal (t1, t2))
-	    continue;
+	    {
+	      *gvn_used = true;
+	      continue;
+	    }
 	  equal = false;
 	  break;
 	}
@@ -1083,12 +1086,16 @@ gimple_equal_p (same_succ same_succ, gim
       if (lhs1 == NULL_TREE || lhs2 == NULL_TREE)
 	return false;
       if (TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME)
-	return vn_valueize (lhs1) == vn_valueize (lhs2);
+	{
+	  *gvn_used = true;
+	  return vn_valueize (lhs1) == vn_valueize (lhs2);
+	}
       return operand_equal_p (lhs1, lhs2, 0);
 
     case GIMPLE_ASSIGN:
       lhs1 = gimple_get_lhs (s1);
       lhs2 = gimple_get_lhs (s2);
+      *gvn_used = true;
       return (TREE_CODE (lhs1) == SSA_NAME
 	      && TREE_CODE (lhs2) == SSA_NAME
 	      && vn_valueize (lhs1) == vn_valueize (lhs2));
@@ -1096,15 +1103,23 @@ gimple_equal_p (same_succ same_succ, gim
     case GIMPLE_COND:
       t1 = gimple_cond_lhs (s1);
       t2 = gimple_cond_lhs (s2);
-      if (!operand_equal_p (t1, t2, 0)
-	  && !gvn_uses_equal (t1, t2))
-	return false;
+      if (!operand_equal_p (t1, t2, 0))
+	{
+	  if (gvn_uses_equal (t1, t2))
+	    *gvn_used = true;
+	  else
+	    return false;
+	}
 
       t1 = gimple_cond_rhs (s1);
       t2 = gimple_cond_rhs (s2);
-      if (!operand_equal_p (t1, t2, 0)
-	  && !gvn_uses_equal (t1, t2))
-	return false;
+      if (!operand_equal_p (t1, t2, 0))
+	{
+	  if (gvn_uses_equal (t1, t2))
+	    *gvn_used = true;
+	  else
+	    return false;
+	}
 
       code1 = gimple_expr_code (s1);
       code2 = gimple_expr_code (s2);
@@ -1126,18 +1141,25 @@ gimple_equal_p (same_succ same_succ, gim
 /* Let GSI skip backwards over local defs.  */
 
 static void
-gsi_advance_bw_nondebug_nonlocal (gimple_stmt_iterator *gsi)
+gsi_advance_bw_nondebug_nonlocal (gimple_stmt_iterator *gsi, tree *vuse)
 {
   gimple stmt;
+  tree lvuse;
 
   while (true)
     {
       if (gsi_end_p (*gsi))
 	return;
       stmt = gsi_stmt (*gsi);
+
+      lvuse = gimple_vuse (stmt);
+      if (lvuse != NULL_TREE)
+	*vuse = lvuse;
+
       if (!(is_gimple_assign (stmt) && local_def (gimple_get_lhs (stmt))
 	    && !gimple_has_side_effects (stmt)))
 	return;
+
       gsi_prev_nondebug (gsi);
     }
 }
@@ -1146,28 +1168,34 @@ gsi_advance_bw_nondebug_nonlocal (gimple
    clusters them.  */
 
 static void
-find_duplicate (same_succ same_succ, basic_block bb1, basic_block bb2)
+find_duplicate (same_succ same_succ, basic_block bb1, basic_block bb2,
+		bool gvn_used)
 {
   gimple_stmt_iterator gsi1 = gsi_last_nondebug_bb (bb1);
   gimple_stmt_iterator gsi2 = gsi_last_nondebug_bb (bb2);
+  tree vuse1 = NULL_TREE, vuse2 = NULL_TREE;
 
-  gsi_advance_bw_nondebug_nonlocal (&gsi1);
-  gsi_advance_bw_nondebug_nonlocal (&gsi2);
+  gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1);
+  gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2);
 
   while (!gsi_end_p (gsi1) && !gsi_end_p (gsi2))
     {
-      if (!gimple_equal_p (same_succ, gsi_stmt (gsi1), gsi_stmt (gsi2)))
+      if (!gimple_equal_p (same_succ, gsi_stmt (gsi1), gsi_stmt (gsi2),
+			   &gvn_used))
 	return;
 
       gsi_prev_nondebug (&gsi1);
       gsi_prev_nondebug (&gsi2);
-      gsi_advance_bw_nondebug_nonlocal (&gsi1);
-      gsi_advance_bw_nondebug_nonlocal (&gsi2);
+      gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1);
+      gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2);
     }
 
   if (!(gsi_end_p (gsi1) && gsi_end_p (gsi2)))
     return;
 
+  if (gvn_used && vuse1 != vuse2)
+    return;
+
   if (dump_file)
     fprintf (dump_file, "find_duplicates: <bb %d> duplicate of <bb %d>\n",
 	     bb1->index, bb2->index);
@@ -1179,7 +1207,7 @@ find_duplicate (same_succ same_succ, bas
    E2 are equal.  */
 
 static bool
-same_phi_alternatives_1 (basic_block dest, edge e1, edge e2)
+same_phi_alternatives_1 (basic_block dest, edge e1, edge e2, bool *gvn_used)
 {
   int n1 = e1->dest_idx, n2 = e2->dest_idx;
   gimple_stmt_iterator gsi;
@@ -1197,7 +1225,10 @@ same_phi_alternatives_1 (basic_block des
       if (operand_equal_for_phi_arg_p (val1, val2))
         continue;
       if (gvn_uses_equal (val1, val2))
-	continue;
+	{
+	  *gvn_used = true;
+	  continue;
+	}
 
       return false;
     }
@@ -1209,7 +1240,8 @@ same_phi_alternatives_1 (basic_block des
    phi alternatives for BB1 and BB2 are equal.  */
 
 static bool
-same_phi_alternatives (same_succ same_succ, basic_block bb1, basic_block bb2)
+same_phi_alternatives (same_succ same_succ, basic_block bb1, basic_block bb2,
+		       bool *gvn_used)
 {
   unsigned int s;
   bitmap_iterator bs;
@@ -1227,7 +1259,7 @@ same_phi_alternatives (same_succ same_su
 
       /* For all phis in bb, the phi alternatives for e1 and e2 need to have
 	 the same value.  */
-      if (!same_phi_alternatives_1 (succ, e1, e2))
+      if (!same_phi_alternatives_1 (succ, e1, e2, gvn_used))
 	return false;
     }
 
@@ -1301,6 +1333,7 @@ find_clusters_1 (same_succ same_succ)
   bitmap_iterator bi, bj;
   int nr_comparisons;
   int max_comparisons = PARAM_VALUE (PARAM_MAX_TAIL_MERGE_COMPARISONS);
+  bool gvn_used;
 
   EXECUTE_IF_SET_IN_BITMAP (same_succ->bbs, 0, i, bi)
     {
@@ -1333,10 +1366,11 @@ find_clusters_1 (same_succ same_succ)
 	  if (!deps_ok_for_redirect (bb1, bb2))
 	    continue;
 
-	  if (!(same_phi_alternatives (same_succ, bb1, bb2)))
+	  gvn_used = false;
+	  if (!(same_phi_alternatives (same_succ, bb1, bb2, &gvn_used)))
 	    continue;
 
-	  find_duplicate (same_succ, bb1, bb2);
+	  find_duplicate (same_succ, bb1, bb2, gvn_used);
         }
     }
 }
Index: gcc/testsuite/gcc.dg/pr52734.c
===================================================================
--- /dev/null (new file)
+++ gcc/testsuite/gcc.dg/pr52734.c (revision 0)
@@ -0,0 +1,35 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+int bbb = 0;
+
+int __attribute__((noinline,noclone)) aaa(void)
+{
+    ++bbb;
+    return 0;
+}
+
+int __attribute__((noinline,noclone)) ccc(void)
+{
+  int ddd;
+  /* bbb == 0 */
+  if (aaa())
+    return bbb;
+
+  /* bbb == 1 */
+  ddd = bbb;
+  /* bbb == ddd == 1 */
+  if (aaa ())
+    return 0;
+  /* bbb == 2, ddd == 1 */
+
+  return ddd;
+}
+
+int main(void)
+{
+    if (ccc() != 1)
+	__builtin_abort();
+    return 0;
+}
+