re PR c/68062 (ICE when comparing vectors)

	PR c/68062
	* c-typeck.c (build_binary_op) [EQ_EXPR, GE_EXPR]: Promote operand
	to unsigned, if needed.  Add -Wsign-compare warning.

	* typeck.c (cp_build_binary_op): Promote operand to unsigned, if
	needed.  Add -Wsign-compare warning.

	* c-c++-common/vector-compare-4.c: New test.

From-SVN: r232894

6 files changed, 101 insertions, 0 deletions

diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index 7d6250e..7999d2a 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,9 @@
+2016-01-27  Marek Polacek  <polacek@redhat.com>
+
+	PR c/68062
+	* c-typeck.c (build_binary_op) [EQ_EXPR, GE_EXPR]: Promote operand
+	to unsigned, if needed.  Add -Wsign-compare warning.
+
 2016-01-26  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/69483
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index d602e33..65925cb 100644
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -11048,6 +11048,20 @@ build_binary_op (location_t location, enum tree_code code,
               return error_mark_node;
             }
 
+	  /* It's not precisely specified how the usual arithmetic
+	     conversions apply to the vector types.  Here, we use
+	     the unsigned type if one of the operands is signed and
+	     the other one is unsigned.  */
+	  if (TYPE_UNSIGNED (type0) != TYPE_UNSIGNED (type1))
+	    {
+	      if (!TYPE_UNSIGNED (type0))
+		op0 = build1 (VIEW_CONVERT_EXPR, type1, op0);
+	      else
+		op1 = build1 (VIEW_CONVERT_EXPR, type0, op1);
+	      warning_at (location, OPT_Wsign_compare, "comparison between "
+			  "types %qT and %qT", type0, type1);
+	    }
+
           /* Always construct signed integer vector type.  */
           intt = c_common_type_for_size (GET_MODE_BITSIZE
 					   (TYPE_MODE (TREE_TYPE (type0))), 0);
@@ -11201,6 +11215,20 @@ build_binary_op (location_t location, enum tree_code code,
               return error_mark_node;
             }
 
+	  /* It's not precisely specified how the usual arithmetic
+	     conversions apply to the vector types.  Here, we use
+	     the unsigned type if one of the operands is signed and
+	     the other one is unsigned.  */
+	  if (TYPE_UNSIGNED (type0) != TYPE_UNSIGNED (type1))
+	    {
+	      if (!TYPE_UNSIGNED (type0))
+		op0 = build1 (VIEW_CONVERT_EXPR, type1, op0);
+	      else
+		op1 = build1 (VIEW_CONVERT_EXPR, type0, op1);
+	      warning_at (location, OPT_Wsign_compare, "comparison between "
+			  "types %qT and %qT", type0, type1);
+	    }
+
           /* Always construct signed integer vector type.  */
           intt = c_common_type_for_size (GET_MODE_BITSIZE
 					   (TYPE_MODE (TREE_TYPE (type0))), 0);
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 493b17a..52fb9d8 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2016-01-27  Marek Polacek  <polacek@redhat.com>
+
+	PR c/68062
+	* typeck.c (cp_build_binary_op): Promote operand to unsigned, if
+	needed.  Add -Wsign-compare warning.
+
 2016-01-27  Ryan Burn  <contact@rnburn.com>
 
 	PR cilkplus/69267
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 0503c6f..d2c23f4 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4823,6 +4823,20 @@ cp_build_binary_op (location_t location,
 	      return error_mark_node;
 	    }
 
+	  /* It's not precisely specified how the usual arithmetic
+	     conversions apply to the vector types.  Here, we use
+	     the unsigned type if one of the operands is signed and
+	     the other one is unsigned.  */
+	  if (TYPE_UNSIGNED (type0) != TYPE_UNSIGNED (type1))
+	    {
+	      if (!TYPE_UNSIGNED (type0))
+		op0 = build1 (VIEW_CONVERT_EXPR, type1, op0);
+	      else
+		op1 = build1 (VIEW_CONVERT_EXPR, type0, op1);
+	      warning_at (location, OPT_Wsign_compare, "comparison between "
+			  "types %qT and %qT", type0, type1);
+	    }
+
 	  /* Always construct signed integer vector type.  */
 	  intt = c_common_type_for_size (GET_MODE_BITSIZE
 					   (TYPE_MODE (TREE_TYPE (type0))), 0);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e674bf4..2cad0c2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-01-27  Marek Polacek  <polacek@redhat.com>
+
+	PR c/68062
+	* c-c++-common/vector-compare-4.c: New test.
+
 2016-01-27  David Malcolm  <dmalcolm@redhat.com>
 
 	PR preprocessor/69126
diff --git a/gcc/testsuite/c-c++-common/vector-compare-4.c b/gcc/testsuite/c-c++-common/vector-compare-4.c
new file mode 100644
index 0000000..b44f474
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/vector-compare-4.c
@@ -0,0 +1,42 @@
+/* PR c/68062 */
+/* { dg-do compile } */
+/* { dg-options "-Wsign-compare" } */
+
+typedef signed char __attribute__ ((vector_size (4))) v4qi;
+typedef unsigned char __attribute__ ((vector_size (4))) uv4qi;
+typedef signed int __attribute__ ((vector_size (4 * __SIZEOF_INT__))) v4si;
+typedef unsigned int __attribute__ ((vector_size (4 * __SIZEOF_INT__))) uv4si;
+
+v4qi
+fn1 (void)
+{
+  v4qi a = { 1, 2, 3, 4 };
+  uv4qi b = { 4, 3, 2, 1 };
+  v4qi v = { 0, 0, 0, 0 };
+
+  v += (a == b); /* { dg-warning "comparison between types" } */
+  v += (a != b); /* { dg-warning "comparison between types" } */
+  v += (a >= b); /* { dg-warning "comparison between types" } */
+  v += (a <= b); /* { dg-warning "comparison between types" } */
+  v += (a > b); /* { dg-warning "comparison between types" } */
+  v += (a < b); /* { dg-warning "comparison between types" } */
+
+  return v;
+}
+
+v4si
+fn2 (void)
+{
+  v4si a = { 1, 2, 3, 4 };
+  uv4si b = { 4, 3, 2, 1 };
+  v4si v = { 0, 0, 0, 0 };
+
+  v += (a == b); /* { dg-warning "comparison between types" } */
+  v += (a != b); /* { dg-warning "comparison between types" } */
+  v += (a >= b); /* { dg-warning "comparison between types" } */
+  v += (a <= b); /* { dg-warning "comparison between types" } */
+  v += (a > b); /* { dg-warning "comparison between types" } */
+  v += (a < b); /* { dg-warning "comparison between types" } */
+
+  return v;
+}