On 10/30/23 23:16, gaosong wrote:
Anyway, I think my previous suggestion is better:
Oh, Could you show more details? I think I didn't get you point.
If you want to track what the program is using, you should do it exactly like the real
kernel: disable the execution unit, have the program trap, and the enable the
execution unit when the trap occurs. At this point, CSR_EUEN enable bits contain
Untested, but something like this.
r~
From 2a5b55a33bc6133cd318856b95b844162779beaf Mon Sep 17 00:00:00 2001
From: Richard Henderson <richard.hender...@linaro.org>
Date: Tue, 31 Oct 2023 07:46:54 -0700
Subject: [PATCH] linux-user/loongarch64: Use traps to track LSX/LASX usage
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/loongarch64/cpu_loop.c | 13 +++++++++++++
target/loongarch/insn_trans/trans_vec.c.inc | 11 -----------
2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/linux-user/loongarch64/cpu_loop.c b/linux-user/loongarch64/cpu_loop.c
index 894fdd111a..73d7b6796a 100644
--- a/linux-user/loongarch64/cpu_loop.c
+++ b/linux-user/loongarch64/cpu_loop.c
@@ -72,6 +72,19 @@ void cpu_loop(CPULoongArchState *env)
case EXCCODE_BCE:
force_sig_fault(TARGET_SIGSYS, TARGET_SI_KERNEL, env->pc);
break;
+
+ /*
+ * Begin with LSX and LASX disabled, then enable on the first trap.
+ * In this way we can tell if the unit is in use. This is used to
+ * choose the layout of any signal frame.
+ */
+ case EXCCODE_SXD:
+ env->CSR_EUEN |= R_CSR_EUEN_SXE_MASK;
+ break;
+ case EXCCODE_ASXD:
+ env->CSR_EUEN |= R_CSR_EUEN_ASXE_MASK;
+ break;
+
case EXCP_ATOMIC:
cpu_exec_step_atomic(cs);
break;
diff --git a/target/loongarch/insn_trans/trans_vec.c.inc b/target/loongarch/insn_trans/trans_vec.c.inc
index 98f856bb29..92b1d22e28 100644
--- a/target/loongarch/insn_trans/trans_vec.c.inc
+++ b/target/loongarch/insn_trans/trans_vec.c.inc
@@ -4,8 +4,6 @@
* Copyright (c) 2022-2023 Loongson Technology Corporation Limited
*/
-#ifndef CONFIG_USER_ONLY
-
static bool check_vec(DisasContext *ctx, uint32_t oprsz)
{
if ((oprsz == 16) && ((ctx->base.tb->flags & HW_FLAGS_EUEN_SXE) == 0)) {
@@ -21,15 +19,6 @@ static bool check_vec(DisasContext *ctx, uint32_t oprsz)
return true;
}
-#else
-
-static bool check_vec(DisasContext *ctx, uint32_t oprsz)
-{
- return true;
-}
-
-#endif
-
static bool gen_vvvv_ptr_vl(DisasContext *ctx, arg_vvvv *a, uint32_t oprsz,
gen_helper_gvec_4_ptr *fn)
{
--
2.34.1
