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feat(cpu): implement CMN

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-01-18 15:09:25 -04:00
parent 903b75c7c4
commit 6177927049
1 changed files with 11 additions and 0 deletions
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11
src/cpu/arm/data_processing.zig
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@ -24,6 +24,7 @@ pub fn dataProcessing(comptime I: bool, comptime S: bool, comptime instrKind: u4
switch (instrKind) {
0x0 => {
// AND
const result = op1 & op2;
cpu.r[rd] = result;
@ -103,6 +104,16 @@ pub fn dataProcessing(comptime I: bool, comptime S: bool, comptime instrKind: u4
cpu.cpsr.c.write(op2 <= op1);
cpu.cpsr.v.write(((op1 ^ result) & (~op2 ^ result)) >> 31 & 1 == 1);
},
0xB => {
// CMN
var result: u32 = undefined;
const didOverflow = @addWithOverflow(u32, op1, op2, &result);
cpu.cpsr.n.write(result >> 31 & 1 == 1);
cpu.cpsr.z.write(result == 0);
cpu.cpsr.c.write(didOverflow);
cpu.cpsr.v.write(((op1 ^ result) & (op2 ^ result)) >> 31 & 1 == 1);
},
0xC => {
// ORR
const result = op1 | op2;