re PR c++/85052 (Implement support for clang's __builtin_convertvector)

	PR c++/85052
	* tree-vect-generic.c: Include insn-config.h and recog.h.
	(expand_vector_piecewise): Add defaulted ret_type argument,
	if non-NULL, use that in preference to type for the result type.
	(expand_vector_parallel): Formatting fix.
	(do_vec_conversion, do_vec_narrowing_conversion,
	expand_vector_conversion): New functions.
	(expand_vector_operations_1): Call expand_vector_conversion
	for VEC_CONVERT ifn calls.
	* internal-fn.def (VEC_CONVERT): New internal function.
	* internal-fn.c (expand_VEC_CONVERT): New function.
	* fold-const-call.c (fold_const_vec_convert): New function.
	(fold_const_call): Use it for CFN_VEC_CONVERT.
	* doc/extend.texi (__builtin_convertvector): Document.
c-family/
	* c-common.h (enum rid): Add RID_BUILTIN_CONVERTVECTOR.
	(c_build_vec_convert): Declare.
	* c-common.c (c_build_vec_convert): New function.
c/
	* c-parser.c (c_parser_postfix_expression): Parse
	__builtin_convertvector.
cp/
	* cp-tree.h (cp_build_vec_convert): Declare.
	* parser.c (cp_parser_postfix_expression): Parse
	__builtin_convertvector.
	* constexpr.c: Include fold-const-call.h.
	(cxx_eval_internal_function): Handle IFN_VEC_CONVERT.
	(potential_constant_expression_1): Likewise.
	* semantics.c (cp_build_vec_convert): New function.
	* pt.c (tsubst_copy_and_build): Handle CALL_EXPR to
	IFN_VEC_CONVERT.
testsuite/
	* c-c++-common/builtin-convertvector-1.c: New test.
	* c-c++-common/torture/builtin-convertvector-1.c: New test.
	* g++.dg/ext/builtin-convertvector-1.C: New test.
	* g++.dg/cpp0x/constexpr-builtin4.C: New test.

From-SVN: r267632

1 files changed, 17 insertions, 0 deletions

diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index 148150b..ed4bbee 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -33,6 +33,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "ubsan.h"
 #include "gimple-fold.h"
 #include "timevar.h"
+#include "fold-const-call.h"
 
 static bool verify_constant (tree, bool, bool *, bool *);
 #define VERIFY_CONSTANT(X)						\
@@ -1449,6 +1450,20 @@ cxx_eval_internal_function (const constexpr_ctx *ctx, tree t,
       return cxx_eval_constant_expression (ctx, CALL_EXPR_ARG (t, 0),
 					   false, non_constant_p, overflow_p);
 
+    case IFN_VEC_CONVERT:
+      {
+	tree arg = cxx_eval_constant_expression (ctx, CALL_EXPR_ARG (t, 0),
+						 false, non_constant_p,
+						 overflow_p);
+	if (TREE_CODE (arg) == VECTOR_CST)
+	  return fold_const_call (CFN_VEC_CONVERT, TREE_TYPE (t), arg);
+	else
+	  {
+	    *non_constant_p = true;
+	    return t;
+	  }
+      }
+
     default:
       if (!ctx->quiet)
 	error_at (cp_expr_loc_or_loc (t, input_location),
@@ -5623,7 +5638,9 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, bool now,
 		case IFN_SUB_OVERFLOW:
 		case IFN_MUL_OVERFLOW:
 		case IFN_LAUNDER:
+		case IFN_VEC_CONVERT:
 		  bail = false;
+		  break;
 
 		default:
 		  break;