target/arm: Use store_reg_from_load in thumb2 code

This function already includes the test for an interworking write
to PC from a load.  Change the T32 LDM implementation to match the
A32 LDM implementation.

For LDM, the reordering of the tests does not change valid
behaviour because the only case that differs is has rn == 15,
which is UNPREDICTABLE.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190904193059.26202-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/translate.c b/target/arm/translate.c
index b0d32ff8c95d91bafe31fb788c440801117eb482..a39f79246331aff0d22470a7baf8381d77f1baa6 100644 (file)
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -9742,13 +9742,11 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
                         /* Load.  */
                         tmp = tcg_temp_new_i32();
                         gen_aa32_ld32u(s, tmp, addr, get_mem_index(s));
-                        if (i == 15) {
-                            gen_bx_excret(s, tmp);
-                        } else if (i == rn) {
+                        if (i == rn) {
                             loaded_var = tmp;
                             loaded_base = 1;
                         } else {
-                            store_reg(s, i, tmp);
+                            store_reg_from_load(s, i, tmp);
                         }
                     } else {
                         /* Store.  */
@@ -10889,11 +10887,7 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
                 tcg_temp_free_i32(addr);
                 goto illegal_op;
             }
-            if (rs == 15) {
-                gen_bx_excret(s, tmp);
-            } else {
-                store_reg(s, rs, tmp);
-            }
+            store_reg_from_load(s, rs, tmp);
         } else {
             /* Store.  */
             tmp = load_reg(s, rs);