target/arm: Drop checks for singlestep_enabled

GDB single-stepping is now handled generically.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-07-18 21:12:59 -10:00
parent db07bd026e
commit 364caea70f
2 changed files with 8 additions and 38 deletions

View file

@ -404,8 +404,6 @@ static inline void gen_goto_tb(DisasContext *s, int n, uint64_t dest)
gen_a64_set_pc_im(dest);
if (s->ss_active) {
gen_step_complete_exception(s);
} else if (s->base.singlestep_enabled) {
gen_exception_internal(EXCP_DEBUG);
} else {
tcg_gen_lookup_and_goto_ptr();
s->base.is_jmp = DISAS_NORETURN;
@ -14879,7 +14877,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
{
DisasContext *dc = container_of(dcbase, DisasContext, base);
if (unlikely(dc->base.singlestep_enabled || dc->ss_active)) {
if (unlikely(dc->ss_active)) {
/* Note that this means single stepping WFI doesn't halt the CPU.
* For conditional branch insns this is harmless unreachable code as
* gen_goto_tb() has already handled emitting the debug exception
@ -14891,11 +14889,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
/* fall through */
case DISAS_EXIT:
case DISAS_JUMP:
if (dc->base.singlestep_enabled) {
gen_exception_internal(EXCP_DEBUG);
} else {
gen_step_complete_exception(dc);
}
gen_step_complete_exception(dc);
break;
case DISAS_NORETURN:
break;

View file

@ -341,7 +341,7 @@ static void gen_exception_internal(int excp)
tcg_temp_free_i32(tcg_excp);
}
static void gen_step_complete_exception(DisasContext *s)
static void gen_singlestep_exception(DisasContext *s)
{
/* We just completed step of an insn. Move from Active-not-pending
* to Active-pending, and then also take the swstep exception.
@ -357,30 +357,6 @@ static void gen_step_complete_exception(DisasContext *s)
s->base.is_jmp = DISAS_NORETURN;
}
static void gen_singlestep_exception(DisasContext *s)
{
/* Generate the right kind of exception for singlestep, which is
* either the architectural singlestep or EXCP_DEBUG for QEMU's
* gdb singlestepping.
*/
if (s->ss_active) {
gen_step_complete_exception(s);
} else {
gen_exception_internal(EXCP_DEBUG);
}
}
static inline bool is_singlestepping(DisasContext *s)
{
/* Return true if we are singlestepping either because of
* architectural singlestep or QEMU gdbstub singlestep. This does
* not include the command line '-singlestep' mode which is rather
* misnamed as it only means "one instruction per TB" and doesn't
* affect the code we generate.
*/
return s->base.singlestep_enabled || s->ss_active;
}
void clear_eci_state(DisasContext *s)
{
/*
@ -837,7 +813,7 @@ static inline void gen_bx_excret_final_code(DisasContext *s)
/* Is the new PC value in the magic range indicating exception return? */
tcg_gen_brcondi_i32(TCG_COND_GEU, cpu_R[15], min_magic, excret_label);
/* No: end the TB as we would for a DISAS_JMP */
if (is_singlestepping(s)) {
if (s->ss_active) {
gen_singlestep_exception(s);
} else {
tcg_gen_exit_tb(NULL, 0);
@ -2606,7 +2582,7 @@ static void gen_goto_tb(DisasContext *s, int n, target_ulong dest)
/* Jump, specifying which TB number to use if we gen_goto_tb() */
static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
{
if (unlikely(is_singlestepping(s))) {
if (unlikely(s->ss_active)) {
/* An indirect jump so that we still trigger the debug exception. */
gen_set_pc_im(s, dest);
s->base.is_jmp = DISAS_JUMP;
@ -9459,7 +9435,7 @@ static void arm_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
dc->page_start = dc->base.pc_first & TARGET_PAGE_MASK;
/* If architectural single step active, limit to 1. */
if (is_singlestepping(dc)) {
if (dc->ss_active) {
dc->base.max_insns = 1;
}
@ -9794,7 +9770,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
* insn codepath itself.
*/
gen_bx_excret_final_code(dc);
} else if (unlikely(is_singlestepping(dc))) {
} else if (unlikely(dc->ss_active)) {
/* Unconditional and "condition passed" instruction codepath. */
switch (dc->base.is_jmp) {
case DISAS_SWI:
@ -9889,7 +9865,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
/* "Condition failed" instruction codepath for the branch/trap insn */
gen_set_label(dc->condlabel);
gen_set_condexec(dc);
if (unlikely(is_singlestepping(dc))) {
if (unlikely(dc->ss_active)) {
gen_set_pc_im(dc, dc->base.pc_next);
gen_singlestep_exception(dc);
} else {