diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2016-02-23 15:36:43 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2016-02-26 15:09:41 +0000 |
| commit | 235ea1f5c89abf30e452539b973b0dbe43d3fe2b (patch) | |
| tree | 926cd2da5ac6f850018a29d2a2a5226ed19e1e95 /target-arm | |
| parent | 4d1e324b2241017c92d816ec3af51a14685dbf62 (diff) | |
target-arm: Give CPSR setting on 32-bit exception return its own helper
The rules for setting the CPSR on a 32-bit exception return are
subtly different from those for setting the CPSR via an instruction
like MSR or CPS. (In particular, in Hyp mode changing the mode bits
is not valid via MSR or CPS.) Split the exception-return case into
its own helper for setting CPSR, so we can eventually handle them
differently in the helper function.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <serge.fdrv@gmail.com>
Message-id: 1455556977-3644-2-git-send-email-peter.maydell@linaro.org
Diffstat (limited to 'target-arm')
| -rw-r--r-- | target-arm/helper.h | 1 | ||||
| -rw-r--r-- | target-arm/op_helper.c | 6 | ||||
| -rw-r--r-- | target-arm/translate.c | 6 |
3 files changed, 10 insertions, 3 deletions
diff --git a/target-arm/helper.h b/target-arm/helper.h index c98e9cea3d..ea13202b17 100644 --- a/target-arm/helper.h +++ b/target-arm/helper.h @@ -57,6 +57,7 @@ DEF_HELPER_2(pre_smc, void, env, i32) DEF_HELPER_1(check_breakpoints, void, env) DEF_HELPER_3(cpsr_write, void, env, i32, i32) +DEF_HELPER_2(cpsr_write_eret, void, env, i32) DEF_HELPER_1(cpsr_read, i32, env) DEF_HELPER_3(v7m_msr, void, env, i32, i32) diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c index 538887ce0c..e3ddd5ad34 100644 --- a/target-arm/op_helper.c +++ b/target-arm/op_helper.c @@ -425,6 +425,12 @@ void HELPER(cpsr_write)(CPUARMState *env, uint32_t val, uint32_t mask) cpsr_write(env, val, mask); } +/* Write the CPSR for a 32-bit exception return */ +void HELPER(cpsr_write_eret)(CPUARMState *env, uint32_t val) +{ + cpsr_write(env, val, CPSR_ERET_MASK); +} + /* Access to user mode registers from privileged modes. */ uint32_t HELPER(get_user_reg)(CPUARMState *env, uint32_t regno) { diff --git a/target-arm/translate.c b/target-arm/translate.c index e69145d401..413f7de686 100644 --- a/target-arm/translate.c +++ b/target-arm/translate.c @@ -4094,7 +4094,7 @@ static void gen_exception_return(DisasContext *s, TCGv_i32 pc) TCGv_i32 tmp; store_reg(s, 15, pc); tmp = load_cpu_field(spsr); - gen_set_cpsr(tmp, CPSR_ERET_MASK); + gen_helper_cpsr_write_eret(cpu_env, tmp); tcg_temp_free_i32(tmp); s->is_jmp = DISAS_JUMP; } @@ -4102,7 +4102,7 @@ static void gen_exception_return(DisasContext *s, TCGv_i32 pc) /* Generate a v6 exception return. Marks both values as dead. */ static void gen_rfe(DisasContext *s, TCGv_i32 pc, TCGv_i32 cpsr) { - gen_set_cpsr(cpsr, CPSR_ERET_MASK); + gen_helper_cpsr_write_eret(cpu_env, cpsr); tcg_temp_free_i32(cpsr); store_reg(s, 15, pc); s->is_jmp = DISAS_JUMP; @@ -9094,7 +9094,7 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn) if (exc_return) { /* Restore CPSR from SPSR. */ tmp = load_cpu_field(spsr); - gen_set_cpsr(tmp, CPSR_ERET_MASK); + gen_helper_cpsr_write_eret(cpu_env, tmp); tcg_temp_free_i32(tmp); s->is_jmp = DISAS_JUMP; } |