diff options
Diffstat (limited to 'docs/devel')
| -rw-r--r-- | docs/devel/tcg-ops.rst | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/docs/devel/tcg-ops.rst b/docs/devel/tcg-ops.rst index f3f451b77f..6a166c5665 100644 --- a/docs/devel/tcg-ops.rst +++ b/docs/devel/tcg-ops.rst @@ -672,19 +672,20 @@ QEMU specific operations | This operation is optional. If the TCG backend does not implement the goto_ptr opcode, emitting this op is equivalent to emitting exit_tb(0). - * - qemu_ld_i32/i64 *t0*, *t1*, *flags*, *memidx* + * - qemu_ld_i32/i64/i128 *t0*, *t1*, *flags*, *memidx* - qemu_st_i32/i64 *t0*, *t1*, *flags*, *memidx* + qemu_st_i32/i64/i128 *t0*, *t1*, *flags*, *memidx* qemu_st8_i32 *t0*, *t1*, *flags*, *memidx* - | Load data at the guest address *t1* into *t0*, or store data in *t0* at guest - address *t1*. The _i32/_i64 size applies to the size of the input/output + address *t1*. The _i32/_i64/_i128 size applies to the size of the input/output register *t0* only. The address *t1* is always sized according to the guest, and the width of the memory operation is controlled by *flags*. | | Both *t0* and *t1* may be split into little-endian ordered pairs of registers - if dealing with 64-bit quantities on a 32-bit host. + if dealing with 64-bit quantities on a 32-bit host, or 128-bit quantities on + a 64-bit host. | | The *memidx* selects the qemu tlb index to use (e.g. user or kernel access). The flags are the MemOp bits, selecting the sign, width, and endianness @@ -693,6 +694,8 @@ QEMU specific operations | For a 32-bit host, qemu_ld/st_i64 is guaranteed to only be used with a 64-bit memory access specified in *flags*. | + | For qemu_ld/st_i128, these are only supported for a 64-bit host. + | | For i386, qemu_st8_i32 is exactly like qemu_st_i32, except the size of the memory operation is known to be 8-bit. This allows the backend to provide a different set of register constraints. |