target/arm: Remove CPSR_RESERVED

The only remaining use was in op_helper.c.  Use PSTATE_SS
directly, and move the commentary so that it is more obvious
what is going on.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200208125816.14954-10-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Richard Henderson 2020-02-08 12:58:05 +00:00 committed by Peter Maydell
parent d203cabd1b
commit 70dae0d069
2 changed files with 8 additions and 7 deletions

View file

@ -387,7 +387,14 @@ void HELPER(exception_bkpt_insn)(CPUARMState *env, uint32_t syndrome)
uint32_t HELPER(cpsr_read)(CPUARMState *env)
{
return cpsr_read(env) & ~(CPSR_EXEC | CPSR_RESERVED);
/*
* We store the ARMv8 PSTATE.SS bit in env->uncached_cpsr.
* This is convenient for populating SPSR_ELx, but must be
* hidden from aarch32 mode, where it is not visible.
*
* TODO: ARMv8.4-DIT -- need to move SS somewhere else.
*/
return cpsr_read(env) & ~(CPSR_EXEC | PSTATE_SS);
}
void HELPER(cpsr_write)(CPUARMState *env, uint32_t val, uint32_t mask)