Update `doc/opcode.md` to reflect the latest bytecode.

- Add `OP_LOADI16`
- Update keyword argument related ops (e.g. OP_KEY_P, etc.)
- Fix some wrong descriptions

1 files changed, 104 insertions, 95 deletions

diff --git a/doc/opcode.md b/doc/opcode.md
index 574a3c83f..0f88664fd 100644
--- a/doc/opcode.md
+++ b/doc/opcode.md
@@ -16,7 +16,6 @@ In the table.1 below, the second field describes the size (and
 sign) of operands.
 
 * B: 8bit
-* sB: signed 8bit
 * S: 16bit
 * sS: signed 16bit
 * W: 24bit
@@ -31,97 +30,107 @@ with `"`, either `OP_EXT1` or `OP_EXT2` or `OP_EXT2` can be prefixed.
 
 ## table.1 Instruction Table
 
-| Instruction Name | Operand type | Semantics        	|
-|:-----------------|--------------|---------------------|
-| OP_NOP           | -            |                  	|
-| OP_MOVE"         | BB           | R(a) = R(b)      	
-| OP_LOADL"        | BB           | R(a) = Pool(b)   	
-| OP_LOADI"        | BsB          | R(a) = mrb_int(b)	
-| OP_LOADI_0'      | B            | R(a) = 0	
-| OP_LOADI_1'      | B            | R(a) = 1	
-| OP_LOADI_2'      | B            | R(a) = 2	
-| OP_LOADI_3'      | B            | R(a) = 3	
-| OP_LOADSYM"      | BB           | R(a) = Syms(b)	
-| OP_LOADNIL'      | B            | R(a) = nil	
-| OP_LOADSELF'     | B            | R(a) = self	
-| OP_LOADT'        | B            | R(a) = true	
-| OP_LOADF'        | B            | R(a) = false	
-| OP_GETGV"        | BB           | R(a) = getglobal(Syms(b))	
-| OP_SETGV"        | BB           | setglobal(Syms(b), R(a))	
-| OP_GETSV"        | BB           | R(a) = Special[b]	
-| OP_SETSV"        | BB           | Special[b] = R(a)	
-| OP_GETIV"        | BB           | R(a) = ivget(Syms(b))	
-| OP_SETIV"        | BB           | ivset(Syms(b),R(a))	
-| OP_GETCV"        | BB           | R(a) = cvget(Syms(b))	
-| OP_SETCV"        | BB           | cvset(Syms(b),R(a))	
-| OP_GETCONST"     | BB           | R(a) = constget(Syms(b))	
-| OP_SETCONST"     | BB           | constset(Syms(b),R(a))	
-| OP_GETMCNST"     | BB           | R(a) = R(a)::Syms(b)	
-| OP_SETMCNST"     | BB           | R(a+1)::Syms(b) = R(a)	
-| OP_GETUPVAR'     | BBB          | R(a) = uvget(b,c)	
-| OP_SETUPVAR'     | BBB          | uvset(b,c,R(a))	
-| OP_JMP           | S            | pc+=a	
-| OP_JMPIF'        | SB           | if R(b) pc+=a	
-| OP_JMPNOT'       | SB           | if !R(b) pc+=a	
-| OP_ONERR         | sS           | rescue_push(pc+a)	
-| OP_EXCEPT'       | B            | R(a) = exc	
-| OP_RESCUE"       | BB           | R(b) = R(a).isa?(R(b))	
-| OP_POPERR        | B            | a.times{rescue_pop()}	
-| OP_RAISE'        | B            | raise(R(a))	
-| OP_EPUSH'        | B            | ensure_push(SEQ[a])	
-| OP_EPOP          | B            | A.times{ensure_pop().call}	
-| OP_SENDV"        | BB           | R(a) = call(R(a),Syms(b),*R(a+1))	
-| OP_SENDVB"       | BB           | R(a) = call(R(a),Syms(b),*R(a+1),&R(a+2))	
-| OP_SEND"         | BBB          | R(a) = call(R(a),Syms(b),R(a+1),...,R(a+c))	
-| OP_SENDB"        | BBB          | R(a) = call(R(a),Syms(Bx),R(a+1),...,R(a+c),&R(a+c+1))	
-| OP_CALL'         | B            | R(a) = self.call(frame.argc, frame.argv)	
-| OP_SUPER'        | BB           | R(a) = super(R(a+1),... ,R(a+b+1))	
-| OP_ARGARY'       | BS           | R(a) = argument array (16=5:1:5:1:4)	
-| OP_ENTER         | W            | arg setup according to flags (23=5:5:1:5:5:1:1)	
-| OP_KARG"         | BB           | R(a) = kdict[Syms(Bx)]                          # todo	
-| OP_KARG2"        | BB           | R(a) = kdict[Syms(Bx)]; kdict.rm(Syms(b))       # todo	
-| OP_RETURN'       | B            | return R(a) (normal)	
-| OP_RETURN_BLK'   | B            | return R(a) (in-block return)	
-| OP_BREAK'        | B            | break R(a)	
-| OP_BLKPUSH'      | BS           | R(a) = block (16=5:1:5:1:4)	
-| OP_ADD"          | BB           | R(a) = R(a)+R(a+1)	
-| OP_ADDI"         | BBB          | R(a) = R(a)+mrb_int(c)	
-| OP_SUB"          | BB           | R(a) = R(a)-R(a+1)	
-| OP_SUBI"         | BB           | R(a) = R(a)-C	
-| OP_MUL"          | BB           | R(a) = R(a)*R(a+1)	
-| OP_DIV"          | BB           | R(a) = R(a)/R(a+1)	
-| OP_EQ"           | BB           | R(a) = R(a)==R(a+1)	
-| OP_LT"           | BB           | R(a) = R(a)<R(a+1)	
-| OP_LE"           | BB           | R(a) = R(a)<=R(a+1)	
-| OP_GT"           | BB           | R(a) = R(a)>R(a+1)	
-| OP_GE"           | BB           | R(a) = R(a)>=R(a+1)	
-| OP_ARRAY'        | BB           | R(a) = ary_new(R(a),R(a+1)..R(a+b))	
-| OP_ARRAY2"       | BB           | R(a) = ary_new(R(b),R(b+1)..R(b+c))	
-| OP_ARYCAT'       | B            | ary_cat(R(a),R(a+1))	
-| OP_ARYPUSH'      | B            | ary_push(R(a),R(a+1))	
-| OP_AREF'         | BB           | R(a) = R(a)[b]	
-| OP_ASET'         | BB           | R(a)[b] = R(a+1)	
-| OP_APOST'        | BB           | *R(a),R(A+1)..R(A+C) = R(a)[B..]	
-| OP_STRING"       | BB           | R(a) = str_dup(Lit(b))	
-| OP_STRCAT'       | B            | str_cat(R(a),R(a+1))	
-| OP_HASH'         | BB           | R(a) = hash_new(R(a),R(a+1)..R(a+b))	
-| OP_HASHADD'      | BB           | R(a) = hash_push(R(a),R(a+1)..R(a+b))	
-| OP_LAMBDA"       | BB           | R(a) = lambda(SEQ[b],OP_L_LAMBDA)	
-| OP_BLOCK"        | BB           | R(a) = lambda(SEQ[b],OP_L_BLOCK)	
-| OP_METHOD"       | BB           | R(a) = lambda(SEQ[b],OP_L_METHOD)	
-| OP_RANGE_INC'    | B            | R(a) = range_new(R(a),R(a+1),FALSE)	
-| OP_RANGE_EXC'    | B            | R(a) = range_new(R(a),R(a+1),TRUE)	
-| OP_OCLASS'       | B            | R(a) = ::Object	
-| OP_CLASS"        | BB           | R(a) = newclass(R(a),Syms(b),R(a+1))	
-| OP_MODULE"       | BB           | R(a) = newmodule(R(a),Syms(b))	
-| OP_EXEC"         | BB           | R(a) = blockexec(R(a),SEQ[b])	
-| OP_DEF"          | BB           | R(a).newmethod(Syms(b),R(a+1))	
-| OP_ALIAS'        | B            | alias_method(R(a),R(a+1),R(a+2))	
-| OP_UNDEF"        | BB           | undef_method(R(a),Syms(b))	
-| OP_SCLASS'       | B            | R(a) = R(a).singleton_class	
-| OP_TCLASS'       | B            | R(a) = target_class	
-| OP_ERR'          | B            | raise(RuntimeError, Lit(Bx))	
-| OP_EXT1          | -            | make 1st operand 16bit	
-| OP_EXT2          | -            | make 2nd operand 16bit	
-| OP_EXT3          | -            | make 1st and 2nd operands 16bit	
-| OP_STOP          | -            | stop VM	
+| Instruction Name | Operand type | Semantics                                              |
+|------------------|--------------|--------------------------------------------------------|
+| OP_NOP           | -            |                                                        |
+| OP_MOVE"         | BB           | R(a) = R(b)                                            |
+| OP_LOADL"        | BB           | R(a) = Pool(b)                                         |
+| OP_LOADI"        | BB           | R(a) = mrb_int(b)                                      |
+| OP_LOADINEG"     | BB           | R(a) = mrb_int(-b)                                     |
+| OP_LOADI__1'     | B            | R(a) = mrb_int(-1)                                     |
+| OP_LOADI_0'      | B            | R(a) = mrb_int(0)                                      |
+| OP_LOADI_1'      | B            | R(a) = mrb_int(1)                                      |
+| OP_LOADI_2'      | B            | R(a) = mrb_int(2)                                      |
+| OP_LOADI_3'      | B            | R(a) = mrb_int(3)                                      |
+| OP_LOADI_4'      | B            | R(a) = mrb_int(4)                                      |
+| OP_LOADI_5'      | B            | R(a) = mrb_int(5)                                      |
+| OP_LOADI_6'      | B            | R(a) = mrb_int(6)                                      |
+| OP_LOADI_7'      | B            | R(a) = mrb_int(7)                                      |
+| OP_LOADI_16'     | BsS          | R(a) = mrb_int(b)                                      |
+| OP_LOADSYM"      | BB           | R(a) = Syms(b)                                         |
+| OP_LOADNIL'      | B            | R(a) = nil                                             |
+| OP_LOADSELF'     | B            | R(a) = self                                            |
+| OP_LOADT'        | B            | R(a) = true                                            |
+| OP_LOADF'        | B            | R(a) = false                                           |
+| OP_GETGV"        | BB           | R(a) = getglobal(Syms(b))                              |
+| OP_SETGV"        | BB           | setglobal(Syms(b), R(a))                               |
+| OP_GETSV"        | BB           | R(a) = Special[b]                                      |
+| OP_SETSV"        | BB           | Special[b] = R(a)                                      |
+| OP_GETIV"        | BB           | R(a) = ivget(Syms(b))                                  |
+| OP_SETIV"        | BB           | ivset(Syms(b),R(a))                                    |
+| OP_GETCV"        | BB           | R(a) = cvget(Syms(b))                                  |
+| OP_SETCV"        | BB           | cvset(Syms(b),R(a))                                    |
+| OP_GETCONST"     | BB           | R(a) = constget(Syms(b))                               |
+| OP_SETCONST"     | BB           | constset(Syms(b),R(a))                                 |
+| OP_GETMCNST"     | BB           | R(a) = R(a)::Syms(b)                                   |
+| OP_SETMCNST"     | BB           | R(a+1)::Syms(b) = R(a)                                 |
+| OP_GETUPVAR'     | BBB          | R(a) = uvget(b,c)                                      |
+| OP_SETUPVAR'     | BBB          | uvset(b,c,R(a))                                        |
+| OP_JMP           | S            | pc=a                                                   |
+| OP_JMPIF'        | SB           | if R(b) pc=a                                           |
+| OP_JMPNOT'       | SB           | if !R(b) pc=a                                          |
+| OP_ONERR         | sS           | rescue_push(pc+a)                                      |
+| OP_EXCEPT'       | B            | R(a) = exc                                             |
+| OP_RESCUE"       | BB           | R(b) = R(a).isa?(R(b))                                 |
+| OP_POPERR        | B            | a.times{rescue_pop()}                                  |
+| OP_RAISE'        | B            | raise(R(a))                                            |
+| OP_EPUSH'        | B            | ensure_push(SEQ[a])                                    |
+| OP_EPOP          | B            | A.times{ensure_pop().call}                             |
+| OP_SENDV"        | BB           | R(a) = call(R(a),Syms(b),*R(a+1))                      |
+| OP_SENDVB"       | BB           | R(a) = call(R(a),Syms(b),*R(a+1),&R(a+2))              |
+| OP_SEND"         | BBB          | R(a) = call(R(a),Syms(b),R(a+1),...,R(a+c))            |
+| OP_SENDB"        | BBB          | R(a) = call(R(a),Syms(Bx),R(a+1),...,R(a+c),&R(a+c+1)) |
+| OP_CALL          | -            | R(0) = self.call(frame.argc, frame.argv)               |
+| OP_SUPER"        | BB           | R(a) = super(R(a+1),... ,R(a+b+1))                     |
+| OP_ARGARY'       | BS           | R(a) = argument array (16=5:1:5:1:4)                   |
+| OP_ENTER         | W            | arg setup according to flags (23=5:5:1:5:5:1:1)        |
+| OP_KEY_P"        | BB           | R(a) = kdict.key?(Syms(b))                             |
+| OP_KEYEND        | -            | raise unless kdict.empty?                              |
+| OP_KARG"         | BB           | R(a) = kdict[Syms(b)]; kdict.delete(Syms(b))           |
+| OP_RETURN'       | B            | return R(a) (normal)                                   |
+| OP_RETURN_BLK'   | B            | return R(a) (in-block return)                          |
+| OP_BREAK'        | B            | break R(a)                                             |
+| OP_BLKPUSH'      | BS           | R(a) = block (16=5:1:5:1:4)                            |
+| OP_ADD"          | BB           | R(a) = R(a)+R(a+1)                                     |
+| OP_ADDI"         | BBB          | R(a) = R(a)+mrb_int(c)                                 |
+| OP_SUB"          | BB           | R(a) = R(a)-R(a+1)                                     |
+| OP_SUBI"         | BB           | R(a) = R(a)-mrb_int(c)                                 |
+| OP_MUL"          | BB           | R(a) = R(a)*R(a+1)                                     |
+| OP_DIV"          | BB           | R(a) = R(a)/R(a+1)                                     |
+| OP_EQ"           | BB           | R(a) = R(a)==R(a+1)                                    |
+| OP_LT"           | BB           | R(a) = R(a)<R(a+1)                                     |
+| OP_LE"           | BB           | R(a) = R(a)<=R(a+1)                                    |
+| OP_GT"           | BB           | R(a) = R(a)>R(a+1)                                     |
+| OP_GE"           | BB           | R(a) = R(a)>=R(a+1)                                    |
+| OP_ARRAY"        | BB           | R(a) = ary_new(R(a),R(a+1)..R(a+b))                    |
+| OP_ARRAY2"       | BBB          | R(a) = ary_new(R(b),R(b+1)..R(b+c))                    |
+| OP_ARYCAT'       | B            | ary_cat(R(a),R(a+1))                                   |
+| OP_ARYPUSH'      | B            | ary_push(R(a),R(a+1))                                  |
+| OP_AREF"         | BBB          | R(a) = R(b)[c]                                         |
+| OP_ASET"         | BBB          | R(a)[c] = R(b)                                         |
+| OP_APOST"        | BBB          | *R(a),R(a+1)..R(a+c) = R(a)[b..]                       |
+| OP_STRING"       | BB           | R(a) = str_dup(Lit(b))                                 |
+| OP_STRCAT'       | B            | str_cat(R(a),R(a+1))                                   |
+| OP_HASH"         | BB           | R(a) = hash_new(R(a),R(a+1)..R(a+b))                   |
+| OP_HASHADD"      | BB           | R(a) = hash_push(R(a),R(a+1)..R(a+b))                  |
+| OP_LAMBDA"       | BB           | R(a) = lambda(SEQ[b],OP_L_LAMBDA)                      |
+| OP_BLOCK"        | BB           | R(a) = lambda(SEQ[b],OP_L_BLOCK)                       |
+| OP_METHOD"       | BB           | R(a) = lambda(SEQ[b],OP_L_METHOD)                      |
+| OP_RANGE_INC'    | B            | R(a) = range_new(R(a),R(a+1),FALSE)                    |
+| OP_RANGE_EXC'    | B            | R(a) = range_new(R(a),R(a+1),TRUE)                     |
+| OP_OCLASS'       | B            | R(a) = ::Object                                        |
+| OP_CLASS"        | BB           | R(a) = newclass(R(a),Syms(b),R(a+1))                   |
+| OP_MODULE"       | BB           | R(a) = newmodule(R(a),Syms(b))                         |
+| OP_EXEC"         | BB           | R(a) = blockexec(R(a),SEQ[b])                          |
+| OP_DEF"          | BB           | R(a).newmethod(Syms(b),R(a+1))                         |
+| OP_ALIAS"        | BB           | alias_method(target_class,Syms(a),Syms(b))             |
+| OP_UNDEF'        | B            | undef_method(target_class,Syms(a))                     |
+| OP_SCLASS'       | B            | R(a) = R(a).singleton_class                            |
+| OP_TCLASS'       | B            | R(a) = target_class                                    |
+| OP_DEBUG"        | BBB          | print a,b,c                                            |
+| OP_ERR'          | B            | raise(RuntimeError, Lit(Bx))                           |
+| OP_EXT1          | -            | make 1st operand 16bit                                 |
+| OP_EXT2          | -            | make 2nd operand 16bit                                 |
+| OP_EXT3          | -            | make 1st and 2nd operands 16bit                        |
+| OP_STOP          | -            | stop VM                                                |
+|------------------|--------------|--------------------------------------------------------|