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feat: pass thumb.gba

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-02-05 20:39:15 -04:00
parent 3ae24d6977
commit aa6f3c7a92
1 changed files with 23 additions and 5 deletions
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28
src/cpu/thumb/block_data_transfer.zig
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@ -50,17 +50,18 @@ pub fn format14(comptime L: bool, comptime R: bool) InstrFn {
pub fn format15(comptime L: bool, comptime rb: u3) InstrFn {
return struct {
fn inner(cpu: *Arm7tdmi, bus: *Bus, opcode: u16) void {
const base = cpu.r[rb];
var address = base;
var address = cpu.r[rb];
const end_address = cpu.r[rb] + 4 * countRlist(opcode);
if (opcode & 0xFF == 0) {
// List is Empty
if (L) cpu.r[15] = bus.read32(address) else bus.write32(address, cpu.r[15]);
if (L) cpu.r[15] = bus.read32(address) else bus.write32(address, cpu.r[15] + 4); // TODO: Why is this r[15] + 4?
cpu.r[rb] += 0x40;
return;
}
var i: u4 = 0;
var first_write = true;
while (i < 8) : (i += 1) {
if (opcode >> i & 1 == 1) {
if (L) {
@ -68,11 +69,28 @@ pub fn format15(comptime L: bool, comptime rb: u3) InstrFn {
} else {
bus.write32(address, cpu.r[i]);
}
if (!L and first_write) {
cpu.r[rb] = end_address;
first_write = false;
}
address += 4;
}
}
cpu.r[rb] = address;
if (L and opcode >> rb & 1 != 1) cpu.r[rb] = address;
}
}.inner;
}
inline fn countRlist(opcode: u16) u32 {
var count: u32 = 0;
comptime var i: u4 = 0;
inline while (i < 8) : (i += 1) {
if (opcode >> (7 - i) & 1 == 1) count += 1;
}
return count;
}