RISC-V: Add support for the 'Zihintntl' extension

This commit adds 'Zihintntl' extension and its hint instructions.

This is based on:
<https://github.com/riscv/riscv-isa-manual/commit/0dc91f505e6da7791d5a733c553e6e2506ddcab5>,
the first ISA Manual noting that the 'Zihintntl' extension is ratified.

Note that compressed 'Zihintntl' hints require either 'C' or
'Zca' extension.

Co-authored-by: Nelson Chu <nelson@rivosinc.com>

bfd/ChangeLog:

	* elfxx-riscv.c (riscv_supported_std_z_ext): Add 'Zihintntl'
	standard hint 'Z' extension.
	(riscv_multi_subset_supports): Support new instruction classes.
	(riscv_multi_subset_supports_ext): Likewise.

gas/ChangeLog:

	* testsuite/gas/riscv/zihintntl.s: New test for 'Zihintntl'
	including auto-compression without C prefix and explicit C prefix.
	* testsuite/gas/riscv/zihintntl.d: Likewise.
	* testsuite/gas/riscv/zihintntl-na.d: Likewise.
	* testsuite/gas/riscv/zihintntl-base.s: New test for correspondence
	between 'Zihintntl' and base 'I' or 'C' instructions.
	* testsuite/gas/riscv/zihintntl-base.d: Likewise.

include/ChangeLog:

	* opcode/riscv.h (enum riscv_insn_class): Add new instruction
	classes: INSN_CLASS_ZIHINTNTL and INSN_CLASS_ZIHINTNTL_AND_C.
	(MASK_NTL_P1, MATCH_NTL_P1, MASK_NTL_PALL,
	MATCH_NTL_PALL, MASK_NTL_S1, MATCH_NTL_S1, MASK_NTL_ALL,
	MATCH_NTL_ALL, MASK_C_NTL_P1, MATCH_C_NTL_P1, MASK_C_NTL_PALL,
	MATCH_C_NTL_PALL, MASK_C_NTL_S1, MATCH_C_NTL_S1, MASK_C_NTL_ALL,
	MATCH_C_NTL_ALL): New.

opcodes/ChangeLog:

	* riscv-opc.c (riscv_opcodes): Add instructions from the
	'Zihintntl' extension.

2 files changed, 28 insertions, 0 deletions

diff --git a/include/opcode/riscv-opc.h b/include/opcode/riscv-opc.h
index 53f5f20..26d2c04 100644
--- a/include/opcode/riscv-opc.h
+++ b/include/opcode/riscv-opc.h
@@ -2298,6 +2298,23 @@
 #define MASK_CZERO_EQZ 0xfe00707f
 #define MATCH_CZERO_NEZ 0xe007033
 #define MASK_CZERO_NEZ 0xfe00707f
+/* Zihintntl hint instructions.  */
+#define MATCH_NTL_P1 0x200033
+#define MASK_NTL_P1 0xffffffff
+#define MATCH_NTL_PALL 0x300033
+#define MASK_NTL_PALL 0xffffffff
+#define MATCH_NTL_S1 0x400033
+#define MASK_NTL_S1 0xffffffff
+#define MATCH_NTL_ALL 0x500033
+#define MASK_NTL_ALL 0xffffffff
+#define MATCH_C_NTL_P1 0x900a
+#define MASK_C_NTL_P1 0xffff
+#define MATCH_C_NTL_PALL 0x900e
+#define MASK_C_NTL_PALL 0xffff
+#define MATCH_C_NTL_S1 0x9012
+#define MASK_C_NTL_S1 0xffff
+#define MATCH_C_NTL_ALL 0x9016
+#define MASK_C_NTL_ALL 0xffff
 /* Zawrs intructions.  */
 #define MATCH_WRS_NTO 0x00d00073
 #define MASK_WRS_NTO 0xffffffff
@@ -3341,6 +3358,15 @@ DECLARE_INSN(cbo_zero, MATCH_CBO_ZERO, MASK_CBO_ZERO);
 /* Zicond instructions. */
 DECLARE_INSN(czero_eqz, MATCH_CZERO_EQZ, MASK_CZERO_EQZ)
 DECLARE_INSN(czero_nez, MATCH_CZERO_NEZ, MASK_CZERO_NEZ)
+/* Zihintntl hint instructions.  */
+DECLARE_INSN(ntl_p1, MATCH_NTL_P1, MASK_NTL_P1);
+DECLARE_INSN(ntl_pall, MATCH_NTL_PALL, MASK_NTL_PALL);
+DECLARE_INSN(ntl_s1, MATCH_NTL_S1, MASK_NTL_S1);
+DECLARE_INSN(ntl_all, MATCH_NTL_ALL, MASK_NTL_ALL);
+DECLARE_INSN(c_ntl_p1, MATCH_C_NTL_P1, MASK_C_NTL_P1);
+DECLARE_INSN(c_ntl_pall, MATCH_C_NTL_PALL, MASK_C_NTL_PALL);
+DECLARE_INSN(c_ntl_s1, MATCH_C_NTL_S1, MASK_C_NTL_S1);
+DECLARE_INSN(c_ntl_all, MATCH_C_NTL_ALL, MASK_C_NTL_ALL);
 /* Zawrs instructions.  */
 DECLARE_INSN(wrs_nto, MATCH_WRS_NTO, MASK_WRS_NTO)
 DECLARE_INSN(wrs_sto, MATCH_WRS_STO, MASK_WRS_STO)
diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h
index 3ed365e..0b8fde9 100644
--- a/include/opcode/riscv.h
+++ b/include/opcode/riscv.h
@@ -392,6 +392,8 @@ enum riscv_insn_class
   INSN_CLASS_ZICOND,
   INSN_CLASS_ZICSR,
   INSN_CLASS_ZIFENCEI,
+  INSN_CLASS_ZIHINTNTL,
+  INSN_CLASS_ZIHINTNTL_AND_C,
   INSN_CLASS_ZIHINTPAUSE,
   INSN_CLASS_ZMMUL,
   INSN_CLASS_ZAWRS,