The tracking issue for this feature is: #133416
This tracks support for additional registers in architectures where inline assembly is already stable.
| Architecture | Register class | Registers | LLVM constraint code |
|---|
| LoongArch | vreg | $vr[0-31] | f |
| LoongArch | xreg | $xr[0-31] | f |
| AArch64 | preg | p[0-16] | Upa |
| Architecture | Register class | Target feature | Allowed types |
|---|
| LoongArch | vreg | lsx | i128, f32, f64,
i8x16, i16x8, i32x4, i64x2, f32x4, f64x2 |
| LoongArch | xreg | lasx | i128, f32, f64,
i8x16, i16x8, i32x4, i64x2, f32x4, f64x2,
i8x32, i16x16, i32x8, i64x4, f32x8, f64x4 |
| AArch64 | vreg | sve | i8xN, i16xB, i32xN, i64xN, f16xN, f32xN, f64xN (scalable vector) |
| AArch64 | preg | sve | i1xN (scalable vector predicate) |
| Architecture | Base register | Aliases |
|---|
| LoongArch | $f[0-7] | $fa[0-7], $vr[0-7], $xr[0-7] |
| LoongArch | $f[8-23] | $ft[0-15], $vr[8-23], $xr[8-23] |
| LoongArch | $f[24-31] | $fs[0-7], $vr[24-31], $xr[24-31] |
| Architecture | Unsupported register | Reason |
|---|
| Architecture | Register class | Modifier | Example output | LLVM modifier |
|---|
| LoongArch | freg | w | $vr0 | w |
| LoongArch | freg | u | $xr0 | u |
| LoongArch | vreg | None | $vr0 | w |
| LoongArch | vreg | u | $xr0 | u |
| LoongArch | xreg | None | $xr0 | u |
| LoongArch | xreg | w | $vr0 | w |
| AArch64 | vreg | z | z0 | z |