fix WFI/WFE length in syndrome register

WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.

Pass the instruction length to HELPER(wfi), use it to decrement pc
appropriately and to pass an is_16bit flag to syn_wfx, which sets
ARM_EL_IL_SHIFT if needed.

Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Message-id: alpine.DEB.2.10.1710241055160.574@sstabellini-ThinkPad-X260
[PMM: move setting of dc->insn for Thumb so it is correct for 32 bit insns]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 9 insertions, 1 deletions

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 6ba4ae92dc..df57dbb11f 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -12125,6 +12125,7 @@ static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
     }
 
     insn = arm_ldl_code(env, dc->pc, dc->sctlr_b);
+    dc->insn = insn;
     dc->pc += 4;
     disas_arm_insn(dc, insn);
 
@@ -12200,6 +12201,7 @@ static void thumb_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
         insn = insn << 16 | insn2;
         dc->pc += 2;
     }
+    dc->insn = insn;
 
     if (dc->condexec_mask && !thumb_insn_is_unconditional(dc, insn)) {
         uint32_t cond = dc->condexec_cond;
@@ -12326,12 +12328,18 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             /* nothing more to generate */
             break;
         case DISAS_WFI:
-            gen_helper_wfi(cpu_env);
+        {
+            TCGv_i32 tmp = tcg_const_i32((dc->thumb &&
+                                          !(dc->insn & (1U << 31))) ? 2 : 4);
+
+            gen_helper_wfi(cpu_env, tmp);
+            tcg_temp_free_i32(tmp);
             /* The helper doesn't necessarily throw an exception, but we
              * must go back to the main loop to check for interrupts anyway.
              */
             tcg_gen_exit_tb(0);
             break;
+        }
         case DISAS_WFE:
             gen_helper_wfe(cpu_env);
             break;