tcg: Add INDEX_op_qemu_{ld,st}_i128

Add opcodes for backend support for 128-bit memory operations.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 7 insertions, 4 deletions

diff --git a/docs/devel/tcg-ops.rst b/docs/devel/tcg-ops.rst
index f3f451b..6a166c5 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.