diff options
| -rw-r--r-- | src/vm/instruction.js | 18 | ||||
| -rw-r--r-- | src/vm/instruction.test.js | 38 |
2 files changed, 56 insertions, 0 deletions
diff --git a/src/vm/instruction.js b/src/vm/instruction.js index 2afd3f7..f323f84 100644 --- a/src/vm/instruction.js +++ b/src/vm/instruction.js @@ -124,3 +124,21 @@ exports.JMZ = function(core, pc, ins) { return [core.normalize(pc, 1)]; } } + + +exports.JMN = function(core, pc, ins) { + let test; + + if (ins.b.mode === AddrMode.Immediate) { + test = (ins.b.value !== 0); + } else { + const src = core.getValue(pc, ins.b); + test = (src.b.value !== 0); + } + + if (test) { + return [core.getLocation(pc, ins.a)]; + } else { + return [core.normalize(pc, 1)]; + } +} diff --git a/src/vm/instruction.test.js b/src/vm/instruction.test.js index 6175ab2..2880da7 100644 --- a/src/vm/instruction.test.js +++ b/src/vm/instruction.test.js @@ -428,3 +428,41 @@ test('JMZ correctly jumps in immediate mode', () => { core.data[pc].b.value = 0; expect(JMZ(core, pc, ins)).toEqual([CORESIZE-1]); }); + + +test('JMN correctly jumps in non-immediate mode', () => { + const core = new Core(CORESIZE); + const pc = 2; + core.data[pc] = { + opcode: 'JMN', + a: { mode: 'direct', value: -3 }, + b: { mode: 'direct', value: 1 }, + }; + core.data[pc+1] = { + opcode: 'JMN', + a: { mode: 'direct', value: -3 }, + b: { mode: 'direct', value: 0 }, + }; + const ins = core.data[pc]; + + expect(JMN(core, pc, ins)).toEqual([pc+1]); + core.data[pc+1].b.value = 1; + expect(JMN(core, pc, ins)).toEqual([CORESIZE-1]); +}); + + +test('JMN correctly jumps in immediate mode', () => { + const core = new Core(CORESIZE); + const pc = 2; + core.data[pc] = { + opcode: 'JMN', + a: { mode: 'direct', value: -3 }, + b: { mode: 'immediate', value: 0 }, + }; + const ins = core.data[pc]; + + expect(JMN(core, pc, ins)).toEqual([pc+1]); + core.data[pc].b.value = 1; + expect(JMN(core, pc, ins)).toEqual([CORESIZE-1]); +}); + |