re PR middle-end/89725 (ICE in get_fnname_from_decl, at varasm.c:1723)

2019-04-01  Bin Cheng  <bin.cheng@linux.alibaba.com>

	PR tree-optimization/89725
	* tree-chrec.c (chrec_contains_symbols): New parameter.  Handle outer
	loop's chrec as invariant symbol.
	* tree-chrec.h (chrec_contains_symbols): New parameter.
	* tree-data-ref.c (analyze_miv_subscript): Pass new argument.
	(build_classic_dist_vector_1, add_other_self_distances): Bypass access
	function of loops not in DDR's loop_nest.
	* tree-data-ref.h (index_in_loop_nest): Add unreachable check.

	* gcc.dg/tree-ssa/pr89725.c: New test.

From-SVN: r270203

7 files changed, 88 insertions, 12 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 73d8a32..a4c5520 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2019-04-01  Bin Cheng  <bin.cheng@linux.alibaba.com>
+
+	PR tree-optimization/89725
+	* tree-chrec.c (chrec_contains_symbols): New parameter.  Handle outer
+	loop's chrec as invariant symbol.
+	* tree-chrec.h (chrec_contains_symbols): New parameter.
+	* tree-data-ref.c (analyze_miv_subscript): Pass new argument.
+	(build_classic_dist_vector_1, add_other_self_distances): Bypass access
+	function of loops not in DDR's loop_nest.
+	* tree-data-ref.h (index_in_loop_nest): Add unreachable check.
+
 2019-04-08  Chenghua Xu  <paul.hua.gm@gmail.com>
 
 	PR target/89623
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 94bc0f1..c8f538b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-04-01  Bin Cheng  <bin.cheng@linux.alibaba.com>
+
+	PR tree-optimization/89725
+	* gcc.dg/tree-ssa/pr89725.c: New test.
+
 2019-04-08  Martin Liska  <mliska@suse.cz>
 
 	* gcc.target/riscv/arch-1.c: Fix expected scanned pattern.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr89725.c b/gcc/testsuite/gcc.dg/tree-ssa/pr89725.c
new file mode 100644
index 0000000..ad826d9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr89725.c
@@ -0,0 +1,28 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -floop-interchange -fno-tree-dce" } */
+int abs (int);
+int find_sad_16x16(int *intra_mode)
+{
+  int current_intra_sad_2,best_intra_sad2;
+  int M1[16][16],M0[4][4][4][4],M3[4],M4[4][4];
+  int i,j,k;
+  int ii,jj;
+  int up_avail, left_avail, left_up_avail;
+  for (i=0;i<17;i++)
+    if (left_up_avail)
+      {
+	for (jj=0;jj<4;jj++)
+	  for (ii=0;ii<4;ii++)
+	    for (j=0;j<4;j++)
+	      for (i=0;i<4;i++)
+		{
+		  M0[i][ii][2][jj]=M3[0]-M3[1];
+		  M0[i][ii][1][jj]=M3[2]+M3[3];
+		  current_intra_sad_2 += abs(M0[i][ii][j][jj]);
+		}
+
+        if(current_intra_sad_2 < best_intra_sad2)
+          best_intra_sad2=current_intra_sad_2;
+      }
+  return 0;
+}
diff --git a/gcc/tree-chrec.c b/gcc/tree-chrec.c
index 3987041..8b5371a 100644
--- a/gcc/tree-chrec.c
+++ b/gcc/tree-chrec.c
@@ -932,10 +932,12 @@ is_multivariate_chrec (const_tree chrec)
     return false;
 }
 
-/* Determines whether the chrec contains symbolic names or not.  */
+/* Determines whether the chrec contains symbolic names or not.  If LOOP isn't
+   NULL, we also consider chrec wrto outer loops of LOOP as symbol.  */
 
 static bool
-chrec_contains_symbols (const_tree chrec, hash_set<const_tree> &visited)
+chrec_contains_symbols (const_tree chrec, hash_set<const_tree> &visited,
+			struct loop *loop)
 {
   int i, n;
 
@@ -952,18 +954,28 @@ chrec_contains_symbols (const_tree chrec, hash_set<const_tree> &visited)
       || TREE_CODE (chrec) == FIELD_DECL)
     return true;
 
+  if (loop != NULL
+      && TREE_CODE (chrec) == POLYNOMIAL_CHREC
+      && flow_loop_nested_p (get_chrec_loop (chrec), loop))
+    return true;
+
   n = TREE_OPERAND_LENGTH (chrec);
   for (i = 0; i < n; i++)
-    if (chrec_contains_symbols (TREE_OPERAND (chrec, i), visited))
+    if (chrec_contains_symbols (TREE_OPERAND (chrec, i), visited, loop))
       return true;
   return false;
 }
 
+/* Return true if CHREC contains any symbols.  If LOOP is not NULL, check if
+   CHREC contains any chrec which is invariant wrto the loop (nest), in other
+   words, chrec defined by outer loops of loop, so from LOOP's point of view,
+   the chrec is considered as a SYMBOL.  */
+
 bool
-chrec_contains_symbols (const_tree chrec)
+chrec_contains_symbols (const_tree chrec, struct loop* loop)
 {
   hash_set<const_tree> visited;
-  return chrec_contains_symbols (chrec, visited);
+  return chrec_contains_symbols (chrec, visited, loop);
 }
 
 /* Determines whether the chrec contains undetermined coefficients.  */
diff --git a/gcc/tree-chrec.h b/gcc/tree-chrec.h
index 6c79322..258b5d5 100644
--- a/gcc/tree-chrec.h
+++ b/gcc/tree-chrec.h
@@ -80,7 +80,7 @@ extern bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple *,
 /* Observers.  */
 extern bool eq_evolutions_p (const_tree, const_tree);
 extern bool is_multivariate_chrec (const_tree);
-extern bool chrec_contains_symbols (const_tree);
+extern bool chrec_contains_symbols (const_tree, struct loop * = NULL);
 extern bool chrec_contains_symbols_defined_in_loop (const_tree, unsigned);
 extern bool chrec_contains_undetermined (const_tree);
 extern bool tree_contains_chrecs (const_tree, int *);
diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index e536b46..51da181 100644
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -4060,9 +4060,9 @@ analyze_miv_subscript (tree chrec_a,
     }
 
   else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest->num)
-	   && !chrec_contains_symbols (chrec_a)
+	   && !chrec_contains_symbols (chrec_a, loop_nest)
 	   && evolution_function_is_affine_in_loop (chrec_b, loop_nest->num)
-	   && !chrec_contains_symbols (chrec_b))
+	   && !chrec_contains_symbols (chrec_b, loop_nest))
     {
       /* testsuite/.../ssa-chrec-35.c
 	 {0, +, 1}_2  vs.  {0, +, 1}_3
@@ -4272,6 +4272,7 @@ build_classic_dist_vector_1 (struct data_dependence_relation *ddr,
 {
   unsigned i;
   lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
+  struct loop *loop = DDR_LOOP_NEST (ddr)[0];
 
   for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++)
     {
@@ -4302,6 +4303,15 @@ build_classic_dist_vector_1 (struct data_dependence_relation *ddr,
 	      return false;
 	    }
 
+	  /* When data references are collected in a loop while data
+	     dependences are analyzed in loop nest nested in the loop, we
+	     would have more number of access functions than number of
+	     loops.  Skip access functions of loops not in the loop nest.
+
+	     See PR89725 for more information.  */
+	  if (flow_loop_nested_p (get_loop (cfun, var_a), loop))
+	    continue;
+
 	  dist = int_cst_value (SUB_DISTANCE (subscript));
 	  index = index_in_loop_nest (var_a, DDR_LOOP_NEST (ddr));
 	  *index_carry = MIN (index, *index_carry);
@@ -4413,6 +4423,7 @@ add_other_self_distances (struct data_dependence_relation *ddr)
   unsigned i;
   int index_carry = DDR_NB_LOOPS (ddr);
   subscript *sub;
+  struct loop *loop = DDR_LOOP_NEST (ddr)[0];
 
   FOR_EACH_VEC_ELT (DDR_SUBSCRIPTS (ddr), i, sub)
     {
@@ -4442,6 +4453,16 @@ add_other_self_distances (struct data_dependence_relation *ddr)
 	      return;
 	    }
 
+	  /* When data references are collected in a loop while data
+	     dependences are analyzed in loop nest nested in the loop, we
+	     would have more number of access functions than number of
+	     loops.  Skip access functions of loops not in the loop nest.
+
+	     See PR89725 for more information.  */
+	  if (flow_loop_nested_p (get_loop (cfun, CHREC_VARIABLE (access_fun)),
+				  loop))
+	    continue;
+
 	  index_carry = MIN (index_carry,
 			     index_in_loop_nest (CHREC_VARIABLE (access_fun),
 						 DDR_LOOP_NEST (ddr)));
diff --git a/gcc/tree-data-ref.h b/gcc/tree-data-ref.h
index 11aa806..2a5082d 100644
--- a/gcc/tree-data-ref.h
+++ b/gcc/tree-data-ref.h
@@ -580,12 +580,11 @@ index_in_loop_nest (int var, vec<loop_p> loop_nest)
   struct loop *loopi;
   int var_index;
 
-  for (var_index = 0; loop_nest.iterate (var_index, &loopi);
-       var_index++)
+  for (var_index = 0; loop_nest.iterate (var_index, &loopi); var_index++)
     if (loopi->num == var)
-      break;
+      return var_index;
 
-  return var_index;
+  gcc_unreachable ();
 }
 
 /* Returns true when the data reference DR the form "A[i] = ..."