MIPS16: Reassign `0' and `4' operand codes

Replace `0' and `4' operand codes with `.' and `F' respectively to free
up the `0'-`4' consecutive range.  No functional change.

	gas/
	* config/tc-mips.c (mips16_macro_build): Replace `0' and `4'
	operand codes with `.' and `F' respectively.
	(mips16_macro): Likewise.

	include/
	* opcode/mips.h: Replace `0' and `4' operand codes with `.' and
	`F' respectively.

	opcodes/
	* mips16-opc.c (decode_mips16_operand): Replace `0' and `4'
	operand codes with `.' and `F' respectively.
	(mips16_opcodes): Likewise.

(cherry picked from commit d8722d7641d234dcd3d1f2254fbc5d9cf234e4e6)

6 files changed, 43 insertions, 25 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 2a2fafb..b181f0c 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,5 +1,11 @@
 2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
 
+	* config/tc-mips.c (mips16_macro_build): Replace `0' and `4'
+	operand codes with `.' and `F' respectively.
+	(mips16_macro): Likewise.
+
+2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
+
 	* config/tc-mips.c (is_size_valid_16): Disallow a `.e' suffix
 	instruction size override for INSN2_SHORT_ONLY opcode table
 	entries.
diff --git a/gas/config/tc-mips.c b/gas/config/tc-mips.c
index 562da64..e6b8c1b 100644
--- a/gas/config/tc-mips.c
+++ b/gas/config/tc-mips.c
@@ -8758,15 +8758,15 @@ mips16_macro_build (expressionS *ep, const char *name, const char *fmt,
 	case ')':
 	  break;
 
-	case '0':
+	case '.':
 	case 'S':
 	case 'P':
 	case 'R':
 	  break;
 
 	case '<':
-	case '4':
 	case '5':
+	case 'F':
 	case 'H':
 	case 'W':
 	case 'D':
@@ -13531,7 +13531,7 @@ mips16_macro (struct mips_cl_insn *ip)
       s = "mfhi";
     do_div3:
       start_noreorder ();
-      macro_build (NULL, dbl ? "ddiv" : "div", "0,x,y", op[1], op[2]);
+      macro_build (NULL, dbl ? "ddiv" : "div", ".,x,y", op[1], op[2]);
       expr1.X_add_number = 2;
       macro_build (&expr1, "bnez", "x,p", op[2]);
       macro_build (NULL, "break", "6", 7);
@@ -13561,7 +13561,7 @@ mips16_macro (struct mips_cl_insn *ip)
       s2 = "mfhi";
     do_divu3:
       start_noreorder ();
-      macro_build (NULL, s, "0,x,y", op[1], op[2]);
+      macro_build (NULL, s, ".,x,y", op[1], op[2]);
       expr1.X_add_number = 2;
       macro_build (&expr1, "bnez", "x,p", op[2]);
       macro_build (NULL, "break", "6", 7);
@@ -13583,7 +13583,7 @@ mips16_macro (struct mips_cl_insn *ip)
     case M_SUBU_I:
     do_subu:
       imm_expr.X_add_number = -imm_expr.X_add_number;
-      macro_build (&imm_expr, dbl ? "daddiu" : "addiu", "y,x,4", op[0], op[1]);
+      macro_build (&imm_expr, dbl ? "daddiu" : "addiu", "y,x,F", op[0], op[1]);
       break;
 
     case M_SUBU_I_2:
diff --git a/include/ChangeLog b/include/ChangeLog
index f771bd1..04c02ce 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,5 +1,10 @@
 2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
 
+	* opcode/mips.h: Replace `0' and `4' operand codes with `.' and
+	`F' respectively.
+
+2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
+
 	* opcode/mips.h (INSN2_SHORT_ONLY): New macro.
 
 2016-12-21  Alan Modra  <amodra@gmail.com>
diff --git a/include/opcode/mips.h b/include/opcode/mips.h
index cf661c8..e00f682 100644
--- a/include/opcode/mips.h
+++ b/include/opcode/mips.h
@@ -1803,7 +1803,7 @@ extern int bfd_mips_num_opcodes;
    "Z" 3 bit register (MIPS16OP_*_MOVE32Z)
    "v" 3 bit same register as source and destination (MIPS16OP_*_RX)
    "w" 3 bit same register as source and destination (MIPS16OP_*_RY)
-   "0" zero register ($0)
+   "." zero register ($0)
    "S" stack pointer ($sp or $29)
    "P" program counter
    "R" return address register ($ra or $31)
@@ -1823,8 +1823,8 @@ extern int bfd_mips_num_opcodes;
    "<" 3 bit unsigned shift count * 0 (MIPS16OP_*_RZ) (full 5 bit unsigned)
    "[" 3 bit unsigned shift count * 0 (MIPS16OP_*_RZ) (full 6 bit unsigned)
    "]" 3 bit unsigned shift count * 0 (MIPS16OP_*_RX) (full 6 bit unsigned)
-   "4" 4 bit signed immediate * 0 (MIPS16OP_*_IMM4) (full 15 bit signed)
    "5" 5 bit unsigned immediate * 0 (MIPS16OP_*_IMM5)
+   "F" 4 bit signed immediate * 0 (MIPS16OP_*_IMM4) (full 15 bit signed)
    "H" 5 bit unsigned immediate * 2 (MIPS16OP_*_IMM5)
    "W" 5 bit unsigned immediate * 4 (MIPS16OP_*_IMM5)
    "D" 5 bit unsigned immediate * 8 (MIPS16OP_*_IMM5)
@@ -1844,9 +1844,9 @@ extern int bfd_mips_num_opcodes;
    "M" 7 bit register list for restore instruction (18 bit extended)
 
    Characters used so far, for quick reference when adding more:
-   "   456 8 0"
-   "[]<"
-   "ABCDE  HI KLM  P RS UVWXYZ"
+   "    56 8  "
+   ".[]<"
+   "ABCDEF HI KLM  P RS UVWXYZ"
    "a   e   ijklm  pq    vwxyz"
   */
 
diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 46b9d83..0df9632 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,5 +1,11 @@
 2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
 
+	* mips16-opc.c (decode_mips16_operand): Replace `0' and `4'
+	operand codes with `.' and `F' respectively.
+	(mips16_opcodes): Likewise.
+
+2016-12-23  Maciej W. Rozycki  <macro@imgtec.com>
+
 	* mips-dis.c (print_insn_mips16): Disallow EXTEND prefix
 	matching for INSN2_SHORT_ONLY opcode table entries.
 	* mips16-opc.c (SH): New macro.
diff --git a/opcodes/mips16-opc.c b/opcodes/mips16-opc.c
index 0c1c7fa..fb0e0b7 100644
--- a/opcodes/mips16-opc.c
+++ b/opcodes/mips16-opc.c
@@ -49,7 +49,8 @@ decode_mips16_operand (char type, bfd_boolean extended_p)
 {
   switch (type)
     {
-    case '0': MAPPED_REG (0, 0, GP, reg_0_map);
+    case '.': MAPPED_REG (0, 0, GP, reg_0_map);
+
     case '6': UINT (6, 5);
 
     case 'L': SPECIAL (6, 5, ENTRY_EXIT_LIST);
@@ -80,7 +81,6 @@ decode_mips16_operand (char type, bfd_boolean extended_p)
       case '[': UINT (6, 0);
       case ']': UINT (6, 0);
 
-      case '4': SINT (15, 0);
       case '5': SINT (16, 0);
       case '8': SINT (16, 0);
 
@@ -89,6 +89,7 @@ decode_mips16_operand (char type, bfd_boolean extended_p)
       case 'C': SINT (16, 0);
       case 'D': SINT (16, 0);
       case 'E': PCREL (16, 0, TRUE, 0, 2, FALSE, FALSE);
+      case 'F': SINT (15, 0);
       case 'H': SINT (16, 0);
       case 'K': SINT (16, 0);
       case 'U': UINT (16, 0);
@@ -107,7 +108,6 @@ decode_mips16_operand (char type, bfd_boolean extended_p)
       case '[': INT_ADJ (3, 2, 8, 0, FALSE);
       case ']': INT_ADJ (3, 8, 8, 0, FALSE);
 
-      case '4': SINT (4, 0);
       case '5': UINT (5, 0);
       case '8': UINT (8, 0);
 
@@ -116,6 +116,7 @@ decode_mips16_operand (char type, bfd_boolean extended_p)
       case 'C': INT_ADJ (8, 0, 255, 3, FALSE);	/* (0 .. 255) << 3 */
       case 'D': INT_ADJ (5, 0, 31, 3, FALSE);	/* (0 .. 31) << 3 */
       case 'E': PCREL (5, 0, FALSE, 2, 2, FALSE, FALSE);
+      case 'F': SINT (4, 0);
       case 'H': INT_ADJ (5, 0, 31, 1, FALSE);	/* (0 .. 31) << 1 */
       case 'K': INT_ADJ (8, 0, 127, 3, FALSE);	/* (-128 .. 127) << 3 */
       case 'U': UINT (8, 0);
@@ -184,14 +185,14 @@ const struct mips_opcode mips16_opcodes[] =
 {"nop",	    "",		0x6500, 0xffff,		0,			SH|RD_16,	I1,	0,	0 }, /* move $0,$Z */
 {"la",	    "x,A",	0x0800, 0xf800,		WR_1,			RD_PC,		I1,	0,	0 },
 {"abs",	    "x,w",	0, (int) M_ABS,		INSN_MACRO,		0,		I1,	0,	0 },
-{"addiu",   "y,x,4",	0x4000, 0xf810,		WR_1|RD_2,		0,		I1,	0,	0 },
+{"addiu",   "y,x,F",	0x4000, 0xf810,		WR_1|RD_2,		0,		I1,	0,	0 },
 {"addiu",   "x,k",	0x4800, 0xf800,		MOD_1,			0,		I1,	0,	0 },
 {"addiu",   "S,K",	0x6300, 0xff00,		0,			MOD_SP,		I1,	0,	0 },
 {"addiu",   "S,S,K",	0x6300, 0xff00,		0,			MOD_SP,		I1,	0,	0 },
 {"addiu",   "x,P,V",	0x0800, 0xf800,		WR_1,			RD_PC,		I1,	0,	0 },
 {"addiu",   "x,S,V",	0x0000, 0xf800,		WR_1,			RD_SP,		I1,	0,	0 },
 {"addu",    "z,v,y",	0xe001, 0xf803,		WR_1|RD_2|RD_3,		SH,		I1,	0,	0 },
-{"addu",    "y,x,4",	0x4000, 0xf810,		WR_1|RD_2,		0,		I1,	0,	0 },
+{"addu",    "y,x,F",	0x4000, 0xf810,		WR_1|RD_2,		0,		I1,	0,	0 },
 {"addu",    "x,k",	0x4800, 0xf800,		MOD_1,			0,		I1,	0,	0 },
 {"addu",    "S,K",	0x6300, 0xff00,		0,			MOD_SP,		I1,	0,	0 },
 {"addu",    "S,S,K",	0x6300, 0xff00,		0,			MOD_SP,		I1,	0,	0 },
@@ -228,33 +229,33 @@ const struct mips_opcode mips16_opcodes[] =
 {"cmp",	    "x,y",	0xe80a, 0xf81f,		RD_1|RD_2|WR_T,		SH,		I1,	0,	0 },
 {"cmp",     "x,U",	0x7000, 0xf800,		RD_1|WR_T,		0,		I1,	0,	0 },
 {"dla",	    "y,E",	0xfe00, 0xff00,		WR_1, 			RD_PC,		I3,	0,	0 },
-{"daddiu",  "y,x,4",	0x4010, 0xf810,		WR_1|RD_2, 		0,		I3,	0,	0 },
+{"daddiu",  "y,x,F",	0x4010, 0xf810,		WR_1|RD_2, 		0,		I3,	0,	0 },
 {"daddiu",  "y,j",	0xfd00, 0xff00,		MOD_1,			0,		I3,	0,	0 },
 {"daddiu",  "S,K",	0xfb00, 0xff00,		0,	 		MOD_SP,		I3,	0,	0 },
 {"daddiu",  "S,S,K",	0xfb00, 0xff00,		0,	 		MOD_SP,		I3,	0,	0 },
 {"daddiu",  "y,P,W",	0xfe00, 0xff00,		WR_1,	 		RD_PC,		I3,	0,	0 },
 {"daddiu",  "y,S,W",	0xff00, 0xff00,		WR_1,			RD_SP,		I3,	0,	0 },
 {"daddu",   "z,v,y",	0xe000, 0xf803,		WR_1|RD_2|RD_3,		SH,		I3,	0,	0 },
-{"daddu",   "y,x,4",	0x4010, 0xf810,		WR_1|RD_2, 		0,		I3,	0,	0 },
+{"daddu",   "y,x,F",	0x4010, 0xf810,		WR_1|RD_2, 		0,		I3,	0,	0 },
 {"daddu",   "y,j",	0xfd00, 0xff00,		MOD_1,			0,		I3,	0,	0 },
 {"daddu",   "S,K",	0xfb00, 0xff00,		0,	 		MOD_SP,		I3,	0,	0 },
 {"daddu",   "S,S,K",	0xfb00, 0xff00,		0,	 		MOD_SP,		I3,	0,	0 },
 {"daddu",   "y,P,W",	0xfe00, 0xff00,		WR_1,	 		RD_PC,		I3,	0,	0 },
 {"daddu",   "y,S,W",	0xff00, 0xff00,		WR_1,			RD_SP,		I3,	0,	0 },
-{"ddiv",    "0,x,y",	0xe81e, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
+{"ddiv",    ".,x,y",	0xe81e, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
 {"ddiv",    "z,v,y",	0, (int) M_DDIV_3,	INSN_MACRO,		0,		I3,	0,	0 },
-{"ddivu",   "0,x,y",	0xe81f, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
+{"ddivu",   ".,x,y",	0xe81f, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
 {"ddivu",   "z,v,y",	0, (int) M_DDIVU_3,	INSN_MACRO,		0,		I3,	0,	0 },
-{"div",	    "0,x,y",	0xe81a, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
+{"div",	    ".,x,y",	0xe81a, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
 {"div",     "z,v,y",	0, (int) M_DIV_3,	INSN_MACRO,		0,		I1,	0,	0 },
-{"divu",    "0,x,y",	0xe81b, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
+{"divu",    ".,x,y",	0xe81b, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
 {"divu",    "z,v,y",	0, (int) M_DIVU_3,	INSN_MACRO,		0,		I1,	0,	0 },
 {"dmul",    "z,v,y",	0, (int) M_DMUL,	INSN_MACRO, 		0,		I3,	0,	0 },
 {"dmult",   "x,y",	0xe81c, 0xf81f,		RD_1|RD_2|WR_HI|WR_LO,	SH,		I3,	0,	0 },
 {"dmultu",  "x,y",	0xe81d, 0xf81f,		RD_1|RD_2|WR_HI|WR_LO,	SH,		I3,	0,	0 },
-{"drem",    "0,x,y",	0xe81e, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
+{"drem",    ".,x,y",	0xe81e, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
 {"drem",    "z,v,y",	0, (int) M_DREM_3,	INSN_MACRO,		0,		I3,	0,	0 },
-{"dremu",   "0,x,y",	0xe81f, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
+{"dremu",   ".,x,y",	0xe81f, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I3,	0,	0 },
 {"dremu",   "z,v,y",	0, (int) M_DREMU_3,	INSN_MACRO,		0,		I3,	0,	0 },
 {"dsllv",   "y,x",	0xe814, 0xf81f,		MOD_1|RD_2,		SH,		I3,	0,	0 },
 {"dsll",    "x,w,[",	0x3001, 0xf803,		WR_1|RD_2, 		0,		I3,	0,	0 },
@@ -315,9 +316,9 @@ const struct mips_opcode mips16_opcodes[] =
 {"neg",	    "x,w",	0xe80b, 0xf81f,		WR_1|RD_2,		SH,		I1,	0,	0 },
 {"not",	    "x,w",	0xe80f, 0xf81f,		WR_1|RD_2,		SH,		I1,	0,	0 },
 {"or",	    "x,y",	0xe80d, 0xf81f,		MOD_1|RD_2,		SH,		I1,	0,	0 },
-{"rem",	    "0,x,y",	0xe81a, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
+{"rem",	    ".,x,y",	0xe81a, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
 {"rem",     "z,v,y",	0, (int) M_REM_3,	INSN_MACRO,		0,		I1,	0,	0 },
-{"remu",    "0,x,y",	0xe81b, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
+{"remu",    ".,x,y",	0xe81b, 0xf81f,		RD_2|RD_3|WR_HI|WR_LO,	SH,		I1,	0,	0 },
 {"remu",    "z,v,y",	0, (int) M_REMU_3,	INSN_MACRO,		0,		I1,	0,	0 },
 {"sb",	    "y,5(x)",	0xc000, 0xf800,		RD_1|RD_3,		0,		I1,	0,	0 },
 {"sd",	    "y,D(x)",	0x7800, 0xf800,		RD_1|RD_3, 		0,		I3,	0,	0 },