RISC-V: Add rounding mode enum for fixed-point intrinsics

Hi, since fixed-point with modeling rounding mode intrinsics are coming:
riscv-non-isa/rvv-intrinsic-doc#222

I am adding vxrm rounding mode enum to user first before the API intrinsic.

This patch is simple && obvious.

Ok for trunk ?

gcc/ChangeLog:

	* config/riscv/riscv-vector-builtins.cc (register_vxrm): New function.
	(DEF_RVV_VXRM_ENUM): New macro.
	(handle_pragma_vector): Add vxrm enum register.
	* config/riscv/riscv-vector-builtins.def (DEF_RVV_VXRM_ENUM): New macro.
	(RNU): Ditto.
	(RNE): Ditto.
	(RDN): Ditto.
	(ROD): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/base/vxrm-1.c: New test.

gcc/config/riscv/riscv-vector-builtins.cc

@@ -3758,6 +3758,19 @@ verify_type_context (location_t loc, type_context_kind context, const_tree type,
   gcc_unreachable ();
 }
 
+/* Register the vxrm enum.  */
+static void
+register_vxrm ()
+{
+  auto_vec<string_int_pair, 4> values;
+#define DEF_RVV_VXRM_ENUM(NAME, VALUE)                                          \
+  values.quick_push (string_int_pair ("VXRM_" #NAME, VALUE));
+#include "riscv-vector-builtins.def"
+#undef DEF_RVV_VXRM_ENUM
+
+  lang_hooks.types.simulate_enum_decl (input_location, "RVV_VXRM", &values);
+}
+
 /* Implement #pragma riscv intrinsic vector.  */
 void
 handle_pragma_vector ()
@@ -3773,6 +3786,9 @@ handle_pragma_vector ()
   for (unsigned int type_i = 0; type_i < NUM_VECTOR_TYPES; ++type_i)
     register_vector_type ((enum vector_type_index) type_i);
 
+  /* Define the enums.  */
+  register_vxrm ();
+
   /* Define the functions.  */
   function_table = new hash_table<registered_function_hasher> (1023);
   function_builder builder;

gcc/config/riscv/riscv-vector-builtins.def

@@ -84,6 +84,11 @@ along with GCC; see the file COPYING3.  If not see
   X64_VLMUL_EXT, TUPLE_SUBPART)
 #endif
 
+/* Define RVV_VXRM rounding mode enum for fixed-point intrinsics.  */
+#ifndef DEF_RVV_VXRM_ENUM
+#define DEF_RVV_VXRM_ENUM(NAME, VALUE)
+#endif
+
 /* SEW/LMUL = 64:
    Only enable when TARGET_MIN_VLEN > 32.
    Machine mode = VNx1BImode when TARGET_MIN_VLEN < 128.
@@ -645,6 +650,11 @@ DEF_RVV_BASE_TYPE (vlmul_ext_x64, get_vector_type (type_idx))
 DEF_RVV_BASE_TYPE (size_ptr, build_pointer_type (size_type_node))
 DEF_RVV_BASE_TYPE (tuple_subpart, get_tuple_subpart_type (type_idx))
 
+DEF_RVV_VXRM_ENUM (RNU, VXRM_RNU)
+DEF_RVV_VXRM_ENUM (RNE, VXRM_RNE)
+DEF_RVV_VXRM_ENUM (RDN, VXRM_RDN)
+DEF_RVV_VXRM_ENUM (ROD, VXRM_ROD)
+
 #include "riscv-vector-type-indexer.gen.def"
 
 #undef DEF_RVV_PRED_TYPE
@@ -653,3 +663,4 @@ DEF_RVV_BASE_TYPE (tuple_subpart, get_tuple_subpart_type (type_idx))
 #undef DEF_RVV_TUPLE_TYPE
 #undef DEF_RVV_BASE_TYPE
 #undef DEF_RVV_TYPE_INDEX
+#undef DEF_RVV_VXRM_ENUM

gcc/testsuite/gcc.target/riscv/rvv/base/vxrm-1.c

@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d -O3" } */
+
+#include "riscv_vector.h"
+
+size_t f0 ()
+{
+  return VXRM_RNU;
+}
+
+size_t f1 ()
+{
+  return VXRM_RNE;
+}
+
+size_t f2 ()
+{
+  return VXRM_RDN;
+}
+
+size_t f3 ()
+{
+  return VXRM_ROD;
+}
+
+/* { dg-final { scan-assembler-times {li\s+[a-x0-9]+,\s*0} 1} } */
+/* { dg-final { scan-assembler-times {li\s+[a-x0-9]+,\s*1} 1} } */
+/* { dg-final { scan-assembler-times {li\s+[a-x0-9]+,\s*2} 1} } */
+/* { dg-final { scan-assembler-times {li\s+[a-x0-9]+,\s*3} 1} } */