const std = @import("std"); const util = @import("../../util.zig"); const Bus = @import("../../Bus.zig"); const Arm7tdmi = @import("../../cpu.zig").Arm7tdmi; const InstrFn = @import("../../cpu.zig").ArmInstrFn; pub fn branch(comptime L: bool) InstrFn { return struct { fn inner(cpu: *Arm7tdmi, _: *Bus, opcode: u32) void { if (L) { // TODO: Debugging beeg.gba w/ MGBA seems to suggest that I don't do anything here cpu.r[14] = cpu.r[15]; } cpu.r[15] = cpu.fakePC() +% util.u32SignExtend(24, opcode << 2); } }.inner; } pub fn branchAndExchange(cpu: *Arm7tdmi, _: *Bus, opcode: u32) void { const rn = opcode & 0xF; cpu.cpsr.t.write(cpu.r[rn] & 1 == 1); // TODO: Is this how I should do it? cpu.r[15] = cpu.r[rn] & 0xFFFF_FFFE; }