On 10/17/23 05:27, Philippe Mathieu-Daudé wrote:
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
---
Based-on: <20231013175109.124308-1-richard.hender...@linaro.org>
tcg: Add tcg_gen_{ld,st}_i128
RFC because unsure and untested...
---
target/m68k/translate.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index 4d0110de95..1e3d155bd9 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -4293,23 +4293,17 @@ DISAS_INSN(chk2)
static void m68k_copy_line(TCGv dst, TCGv src, int index)
{
+ MemOp mop = MO_128 | MO_TE;
+ TCGv_i128 t = tcg_temp_new_i128();
TCGv addr;
- TCGv_i64 t0, t1;
addr = tcg_temp_new();
- t0 = tcg_temp_new_i64();
- t1 = tcg_temp_new_i64();
-
tcg_gen_andi_i32(addr, src, ~15);
- tcg_gen_qemu_ld_i64(t0, addr, index, MO_TEUQ);
- tcg_gen_addi_i32(addr, addr, 8);
- tcg_gen_qemu_ld_i64(t1, addr, index, MO_TEUQ);
+ tcg_gen_qemu_ld_i128(t, addr, index, mop);
tcg_gen_andi_i32(addr, dst, ~15);
- tcg_gen_qemu_st_i64(t0, addr, index, MO_TEUQ);
- tcg_gen_addi_i32(addr, addr, 8);
- tcg_gen_qemu_st_i64(t1, addr, index, MO_TEUQ);
+ tcg_gen_st_i128(t, addr, index);
Aside from the typo, the other thing you need to consider when introducing 16-byte
operations is the atomicity. Do you want or need this to be atomic?
For m68k, I strongly suspect that we don't need the entire read or write to be
atomic.
The manual says "burst reads and writes" without defining those terms. I suspect that
MO_ATOM_NONE is sufficient, but MO_ATOM_IFALIGN_PAIR would preserve the atomicity of the
current code.
r~
