fix: resolve off-by-one error in `str` addr when r15 is involved

I seem to have made up this rule (I was thinking about when r15 was
a source register). `rn` is the destination register.... whoops
This commit is contained in:
Rekai Nyangadzayi Musuka 2023-01-29 08:57:20 -06:00
parent 3f72367aaf
commit c0e583d20d
1 changed files with 1 additions and 3 deletions

View File

@ -11,9 +11,7 @@ pub fn singleDataTransfer(comptime I: bool, comptime P: bool, comptime U: bool,
const rn = opcode >> 16 & 0xF;
const rd = opcode >> 12 & 0xF;
// rn is r15 and L is not set, the PC is 12 ahead
const base = cpu.r[rn] + if (!L and rn == 0xF) 4 else @as(u32, 0);
const base = cpu.r[rn];
const offset = if (I) shifter.immediate(false, cpu, opcode) else opcode & 0xFFF;
const modified_base = if (U) base +% offset else base -% offset;