From a82b615074c5810dfc1e2c45fd28c3833bb1ab0c Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Sun, 7 Jan 2018 02:15:02 +0100 Subject: cleanup --- parse.go | 36 +++++++++++++++--------------------- 1 file changed, 15 insertions(+), 21 deletions(-) (limited to 'parse.go') diff --git a/parse.go b/parse.go index 3777c76..f903b58 100644 --- a/parse.go +++ b/parse.go @@ -2,25 +2,19 @@ package j1 import "fmt" -func isLit(v uint16) bool { return v&(1<<15) != 0 } -func isJump(v uint16) bool { return v&(7<<13) == 0 } -func isCond(v uint16) bool { return v&(7<<13) == 1<<13 } -func isCall(v uint16) bool { return v&(7<<13) == 2<<13 } -func isALU(v uint16) bool { return v&(7<<13) == 3<<13 } - // Decode instruction func Decode(v uint16) Instruction { switch { - case isLit(v): - return ParseLit(v) - case isJump(v): - return ParseJump(v) - case isCond(v): - return ParseCond(v) - case isCall(v): - return ParseCall(v) - case isALU(v): - return ParseALU(v) + case v&(1<<15) != 0: + return newLit(v) + case v&(7<<13) == 0: + return newJump(v) + case v&(7<<13) == 1<<13: + return newCond(v) + case v&(7<<13) == 2<<13: + return newCall(v) + case v&(7<<13) == 3<<13: + return newALU(v) } return nil } @@ -35,7 +29,7 @@ type Instruction interface { // Lit is a literal type Lit uint16 -func ParseLit(v uint16) Lit { return Lit(v &^ uint16(1<<15)) } +func newLit(v uint16) Lit { return Lit(v &^ uint16(1<<15)) } func (v Lit) String() string { return fmt.Sprintf("LIT %0.4X", uint16(v)) } func (v Lit) Value() uint16 { return uint16(v) } func (v Lit) Compile() uint16 { return v.Value() | (1 << 15) } @@ -43,7 +37,7 @@ func (v Lit) Compile() uint16 { return v.Value() | (1 << 15) } // Jump is an unconditional branch type Jump uint16 -func ParseJump(v uint16) Jump { return Jump(v &^ uint16(7<<13)) } +func newJump(v uint16) Jump { return Jump(v &^ uint16(7<<13)) } func (v Jump) String() string { return fmt.Sprintf("UBRANCH %0.4X", uint16(v<<1)) } func (v Jump) Value() uint16 { return uint16(v) } func (v Jump) Compile() uint16 { return v.Value() } @@ -51,7 +45,7 @@ func (v Jump) Compile() uint16 { return v.Value() } // Cond is a conditional branch type Cond uint16 -func ParseCond(v uint16) Cond { return Cond(v &^ uint16(7<<13)) } +func newCond(v uint16) Cond { return Cond(v &^ uint16(7<<13)) } func (v Cond) String() string { return fmt.Sprintf("0BRANCH %0.4X", uint16(v<<1)) } func (v Cond) Value() uint16 { return uint16(v) } func (v Cond) Compile() uint16 { return v.Value() | (1 << 13) } @@ -59,7 +53,7 @@ func (v Cond) Compile() uint16 { return v.Value() | (1 << 13) } // Call procedure type Call uint16 -func ParseCall(v uint16) Call { return Call(v &^ uint16(7<<13)) } +func newCall(v uint16) Call { return Call(v &^ uint16(7<<13)) } func (v Call) String() string { return fmt.Sprintf("CALL %0.4X", uint16(v<<1)) } func (v Call) Value() uint16 { return uint16(v) } func (v Call) Compile() uint16 { return v.Value() | (2 << 13) } @@ -75,7 +69,7 @@ type ALU struct { Ddir int8 } -func ParseALU(v uint16) ALU { +func newALU(v uint16) ALU { return ALU{ Opcode: (v >> 8) & 15, RtoPC: v&(1<<12) != 0, -- cgit v1.2.3