match.pd: X + X --> X * 2 for integers

2016-04-26  Marc Glisse  <marc.glisse@inria.fr>

gcc/
	* genmatch.c (write_predicate): Add ATTRIBUTE_UNUSED.
	* fold-const.c (fold_binary_loc): Remove 2 transformations
	superseded by match.pd.
	* match.pd (x+x -> x*2): Generalize to integers.

gcc/testsuite/
	* gcc.dg/fold-plusmult.c: Adjust.
	* gcc.dg/no-strict-overflow-6.c: Adjust.
	* gcc.dg/gomp/loop-1.c: Xfail some tests.

From-SVN: r235444

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2016-04-26  Marc Glisse  <marc.glisse@inria.fr>
+
+	* genmatch.c (write_predicate): Add ATTRIBUTE_UNUSED.
+	* fold-const.c (fold_binary_loc): Remove 2 transformations
+	superseded by match.pd.
+	* match.pd (x+x -> x*2): Generalize to integers.
+
 2016-04-26  Bernd Schmidt  <bschmidt@redhat.com>
 
 	* config/i386/i386.md (operation on memory peephole): Duplicate an

gcc/fold-const.c

@@ -9956,25 +9956,6 @@ fold_binary_loc (location_t loc,
 				    fold_convert_loc (loc, type,
 						      negate_expr (op0)), tem);
 
-	  /* (A + A) * C -> A * 2 * C  */
-	  if (TREE_CODE (arg0) == PLUS_EXPR
-	      && TREE_CODE (arg1) == INTEGER_CST
-	      && operand_equal_p (TREE_OPERAND (arg0, 0),
-			          TREE_OPERAND (arg0, 1), 0))
-	    return fold_build2_loc (loc, MULT_EXPR, type,
-				omit_one_operand_loc (loc, type,
-						  TREE_OPERAND (arg0, 0),
-						  TREE_OPERAND (arg0, 1)),
-				fold_build2_loc (loc, MULT_EXPR, type,
-					     build_int_cst (type, 2) , arg1));
-
-	  /* ((T) (X /[ex] C)) * C cancels out if the conversion is
-	     sign-changing only.  */
-	  if (TREE_CODE (arg1) == INTEGER_CST
-	      && TREE_CODE (arg0) == EXACT_DIV_EXPR
-	      && operand_equal_p (arg1, TREE_OPERAND (arg0, 1), 0))
-	    return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
-
 	  strict_overflow_p = false;
 	  if (TREE_CODE (arg1) == INTEGER_CST
 	      && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,

gcc/genmatch.c

@@ -3556,7 +3556,7 @@ write_predicate (FILE *f, predicate_id *p, decision_tree &dt, bool gimple)
 	   "%s%s (tree t%s%s)\n"
 	   "{\n", gimple ? "gimple_" : "tree_", p->id,
 	   p->nargs > 0 ? ", tree *res_ops" : "",
-	   gimple ? ", tree (*valueize)(tree)" : "");
+	   gimple ? ", tree (*valueize)(tree) ATTRIBUTE_UNUSED" : "");
   /* Conveniently make 'type' available.  */
   fprintf_indent (f, 2, "tree type = TREE_TYPE (t);\n");
 

gcc/match.pd

@@ -1628,11 +1628,13 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
    (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
     (minus @0 { tem; })))))
 
-/* Convert x+x into x*2.0.  */
+/* Convert x+x into x*2.  */
 (simplify
  (plus @0 @0)
  (if (SCALAR_FLOAT_TYPE_P (type))
-  (mult @0 { build_real (type, dconst2); })))
+  (mult @0 { build_real (type, dconst2); })
+  (if (INTEGRAL_TYPE_P (type))
+   (mult @0 { build_int_cst (type, 2); }))))
 
 (simplify
  (minus integer_zerop @1)

gcc/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2016-04-26  Marc Glisse  <marc.glisse@inria.fr>
+
+	* gcc.dg/fold-plusmult.c: Adjust.
+	* gcc.dg/no-strict-overflow-6.c: Adjust.
+	* gcc.dg/gomp/loop-1.c: Xfail some tests.
+
 2016-04-26  Bernd Schmidt  <bschmidt@redhat.com>
 
 	* gcc.target/i386/avx512bw-vptestmb-1.c: Correct [xyz]mm register

gcc/testsuite/gcc.dg/fold-plusmult.c

@@ -11,4 +11,4 @@ int test2 (int a)
   return (a + a)*2;
 }
 
-/* { dg-final { scan-tree-dump-times "<a> \\\* 4" 2 "original" } } */
+/* { dg-final { scan-tree-dump-times "a \\\* 4" 2 "original" } } */

gcc/testsuite/gcc.dg/gomp/loop-1.c

@@ -44,14 +44,14 @@ f1 (int x)
   #pragma omp for
   for (i = 5; i <= i; i++) /* { dg-error "invalid controlling predicate|condition expression refers to iteration variable" } */
     ;
-  #pragma omp for /* { dg-error "increment expression refers to iteration variable" } */
-  for (i = 5; i < 16; i += i)
+  #pragma omp for /* { dg-error "increment expression refers to iteration variable" "" { xfail *-*-* } } */
+  for (i = 5; i < 16; i += i) /* { dg-bogus "invalid increment expression" "" { xfail *-*-* } } */
     ;
   #pragma omp for
   for (i = 5; i < 16; i = i + 2 * i) /* { dg-error "invalid increment expression|increment expression refers to iteration variable" } */
     ;
-  #pragma omp for /* { dg-error "increment expression refers to iteration variable" } */
-  for (i = 5; i < 16; i = i + i)
+  #pragma omp for /* { dg-error "increment expression refers to iteration variable" "" { xfail *-*-* } } */
+  for (i = 5; i < 16; i = i + i) /* { dg-bogus "invalid increment expression" "" { xfail *-*-* } } */
     ;
   #pragma omp for
   for (i = 5; i < 16; i = i + bar (i)) /* { dg-error "increment expression refers to iteration variable" } */
@@ -181,14 +181,14 @@ f2 (int x)
   #pragma omp for
   for (int i = 5; i <= i; i++) /* { dg-error "invalid controlling predicate|condition expression refers to iteration variable" } */
     ;
-  #pragma omp for /* { dg-error "increment expression refers to iteration variable" } */
-  for (int i = 5; i < 16; i += i)
+  #pragma omp for /* { dg-error "increment expression refers to iteration variable" "" { xfail *-*-* } } */
+  for (int i = 5; i < 16; i += i) /* { dg-bogus "invalid increment expression" "" { xfail *-*-* } } */
     ;
   #pragma omp for
   for (int i = 5; i < 16; i = i + 2 * i) /* { dg-error "invalid increment expression|increment expression refers to iteration variable" } */
     ;
-  #pragma omp for /* { dg-error "increment expression refers to iteration variable" } */
-  for (int i = 5; i < 16; i = i + i)
+  #pragma omp for /* { dg-error "increment expression refers to iteration variable" "" { xfail *-*-* } } */
+  for (int i = 5; i < 16; i = i + i) /* { dg-bogus "invalid increment expression" "" { xfail *-*-* } } */
     ;
   #pragma omp for
   for (int i = 5; i < 16; i = i + bar (i)) /* { dg-error "increment expression refers to iteration variable" } */

gcc/testsuite/gcc.dg/no-strict-overflow-6.c

@@ -14,7 +14,7 @@ foo ()
   int i, bits;
   for (i = 1, bits = 1; i > 0; i += i)
     ++bits;
-  return bits;
+  return bits - sizeof(int) * __CHAR_BIT__;
 }
 
-/* { dg-final { scan-tree-dump "return bits" "optimized" } } */
+/* { dg-final { scan-tree-dump "return 0" "optimized" } } */