[PATCH 4/5] RISC-V: Prefetch hint instructions and operand set

[Tsukasa OI <research_trasio@irq.a4lg.com>]

This commit adds 'Zicbop' hint instructions.

bfd/ChangeLog:

	* elfxx-riscv.c (riscv_multi_subset_supports): Add handling for
	new instruction class.

gas/ChangeLog:

	* config/tc-riscv.c (riscv_ip): Add handling for new operand
	type 'f' (32-byte aligned pseudo S-type immediate for prefetch
	hints).
	(validate_riscv_insn): Likewise.

include/ChangeLog:

	* opcode/riscv-opc.h (MATCH_PREFETCH_I, MASK_PREFETCH_I,
	MATCH_PREFETCH_R, MASK_PREFETCH_R, MATCH_PREFETCH_W,
	MASK_PREFETCH_W): New macros.
	* opcode/riscv.h (enum riscv_insn_class): Add new instruction
	class INSN_CLASS_ZICBOP.

opcodes/ChangeLog:

	* riscv-dis.c (print_insn_args): Add handling for new operand
	type.
	* riscv-opc.c (riscv_opcodes): Add prefetch hint instructions.
---
 bfd/elfxx-riscv.c          |  2 ++
 gas/config/tc-riscv.c      | 18 ++++++++++++++++++
 include/opcode/riscv-opc.h |  7 +++++++
 include/opcode/riscv.h     |  1 +
 opcodes/riscv-dis.c        |  4 ++++
 opcodes/riscv-opc.c        |  3 +++
 6 files changed, 35 insertions(+)

diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
index a7cd9320655..2bd45a0bf17 100644
--- a/bfd/elfxx-riscv.c
+++ b/bfd/elfxx-riscv.c
@@ -2336,6 +2336,8 @@ riscv_multi_subset_supports (riscv_parse_subset_t *rps,
       return riscv_subset_supports (rps, "i");
     case INSN_CLASS_ZICBOM:
       return riscv_subset_supports (rps, "zicbom");
+    case INSN_CLASS_ZICBOP:
+      return riscv_subset_supports (rps, "zicbop");
     case INSN_CLASS_ZICBOZ:
       return riscv_subset_supports (rps, "zicboz");
     case INSN_CLASS_ZICSR:
diff --git a/gas/config/tc-riscv.c b/gas/config/tc-riscv.c
index 25908597436..ddddb0989b1 100644
--- a/gas/config/tc-riscv.c
+++ b/gas/config/tc-riscv.c
@@ -1160,6 +1160,7 @@ validate_riscv_insn (const struct riscv_opcode *opc, int length)
 	case 'a': used_bits |= ENCODE_JTYPE_IMM (-1U); break;
 	case 'p': used_bits |= ENCODE_BTYPE_IMM (-1U); break;
 	case 'q': used_bits |= ENCODE_STYPE_IMM (-1U); break;
+	case 'f': used_bits |= ENCODE_STYPE_IMM (-1U); break;
 	case 'u': used_bits |= ENCODE_UTYPE_IMM (-1U); break;
 	case 'z': break; /* Zero immediate.  */
 	case '[': break; /* Unused operand.  */
@@ -3163,6 +3164,23 @@ riscv_ip (char *str, struct riscv_cl_insn *ip, expressionS *imm_expr,
 	      imm_expr->X_op = O_absent;
 	      continue;
 
+	    case 'f': /* Prefetch offset, pseudo S-type but lower 5-bits zero.  */
+	      if (riscv_handle_implicit_zero_offset (imm_expr, asarg))
+		continue;
+	      my_getExpression (imm_expr, asarg);
+	      check_absolute_expr (ip, imm_expr, false);
+	      if (((unsigned) (imm_expr->X_add_number) & 0x1fU)
+		  || imm_expr->X_add_number >= (signed) RISCV_IMM_REACH / 2
+		  || imm_expr->X_add_number < -(signed) RISCV_IMM_REACH / 2)
+		as_bad (_("improper prefetch offset (%ld)"),
+			(long) imm_expr->X_add_number);
+	      ip->insn_opcode |=
+		ENCODE_STYPE_IMM ((unsigned) (imm_expr->X_add_number) &
+				  ~ 0x1fU);
+	      imm_expr->X_op = O_absent;
+	      asarg = expr_end;
+	      continue;
+
 	    default:
 	    unknown_riscv_ip_operand:
 	      as_fatal (_("internal: unknown argument type `%s'"),
diff --git a/include/opcode/riscv-opc.h b/include/opcode/riscv-opc.h
index b24e8a47c87..203bcdb9212 100644
--- a/include/opcode/riscv-opc.h
+++ b/include/opcode/riscv-opc.h
@@ -2038,6 +2038,13 @@
 #define MASK_CBO_INVAL 0xfff07fff
 #define MATCH_CBO_ZERO 0x40200f
 #define MASK_CBO_ZERO 0xfff07fff
+/* Zicbop hint instructions. */
+#define MATCH_PREFETCH_I 0x6013
+#define MASK_PREFETCH_I 0x1f07fff
+#define MATCH_PREFETCH_R 0x106013
+#define MASK_PREFETCH_R 0x1f07fff
+#define MATCH_PREFETCH_W 0x306013
+#define MASK_PREFETCH_W 0x1f07fff
 /* Privileged CSR addresses.  */
 #define CSR_USTATUS 0x0
 #define CSR_UIE 0x4
diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h
index 1d74f0e521a..b769769b4ec 100644
--- a/include/opcode/riscv.h
+++ b/include/opcode/riscv.h
@@ -389,6 +389,7 @@ enum riscv_insn_class
   INSN_CLASS_ZVEF,
   INSN_CLASS_SVINVAL,
   INSN_CLASS_ZICBOM,
+  INSN_CLASS_ZICBOP,
   INSN_CLASS_ZICBOZ,
 };
 
diff --git a/opcodes/riscv-dis.c b/opcodes/riscv-dis.c
index 34724d4aec5..57b798d8e14 100644
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -424,6 +424,10 @@ print_insn_args (const char *oparg, insn_t l, bfd_vma pc, disassemble_info *info
 	  print (info->stream, "%d", (int)EXTRACT_STYPE_IMM (l));
 	  break;
 
+	case 'f':
+	  print (info->stream, "%d", (int)EXTRACT_STYPE_IMM (l));
+	  break;
+
 	case 'a':
 	  info->target = EXTRACT_JTYPE_IMM (l) + pc;
 	  (*info->print_address_func) (info->target, info);
diff --git a/opcodes/riscv-opc.c b/opcodes/riscv-opc.c
index f092e975bd8..23716b6b7c9 100644
--- a/opcodes/riscv-opc.c
+++ b/opcodes/riscv-opc.c
@@ -388,6 +388,9 @@ const struct riscv_opcode riscv_opcodes[] =
 {"lw",          0, INSN_CLASS_I, "d,o(s)",    MATCH_LW, MASK_LW, match_opcode, INSN_DREF|INSN_4_BYTE },
 {"lw",          0, INSN_CLASS_I, "d,A",       0, (int) M_LW, match_never, INSN_MACRO },
 {"not",         0, INSN_CLASS_I, "d,s",       MATCH_XORI|MASK_IMM, MASK_XORI|MASK_IMM, match_opcode, INSN_ALIAS },
+{"prefetch.i",  0, INSN_CLASS_ZICBOP, "f(s)", MATCH_PREFETCH_I, MASK_PREFETCH_I, match_opcode, 0 },
+{"prefetch.r",  0, INSN_CLASS_ZICBOP, "f(s)", MATCH_PREFETCH_R, MASK_PREFETCH_R, match_opcode, 0 },
+{"prefetch.w",  0, INSN_CLASS_ZICBOP, "f(s)", MATCH_PREFETCH_W, MASK_PREFETCH_W, match_opcode, 0 },
 {"ori",         0, INSN_CLASS_I, "d,s,j",     MATCH_ORI, MASK_ORI, match_opcode, 0 },
 {"or",          0, INSN_CLASS_C, "Cs,Cw,Ct",  MATCH_C_OR, MASK_C_OR, match_opcode, INSN_ALIAS },
 {"or",          0, INSN_CLASS_C, "Cs,Ct,Cw",  MATCH_C_OR, MASK_C_OR, match_opcode, INSN_ALIAS },
-- 
2.32.0