target-xtensa: avoid double-stopping at breakpoints

env->exception_taken is set every time an exception is taken. It is used
to allow single-stepping to stop at the first exception handler
instruction. This however must exclude debug exceptions, as otherwise
first step from the instruction where breakpoint was hit stops at that
same instruction.
Also don't check env->exception_taken directly from the
gen_intermediate_code_internal, instead allocate and use TB flag
XTENSA_TBFLAG_EXCEPTION.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2013-03-04 07:02:00 +04:00
parent 5739006b9a
commit a00817cc4c
3 changed files with 8 additions and 2 deletions

View file

@ -484,6 +484,7 @@ static inline int cpu_mmu_index(CPUXtensaState *env)
#define XTENSA_TBFLAG_ICOUNT 0x20
#define XTENSA_TBFLAG_CPENABLE_MASK 0x3fc0
#define XTENSA_TBFLAG_CPENABLE_SHIFT 6
#define XTENSA_TBFLAG_EXCEPTION 0x4000
static inline void cpu_get_tb_cpu_state(CPUXtensaState *env, target_ulong *pc,
target_ulong *cs_base, int *flags)
@ -510,6 +511,9 @@ static inline void cpu_get_tb_cpu_state(CPUXtensaState *env, target_ulong *pc,
if (xtensa_option_enabled(env->config, XTENSA_OPTION_COPROCESSOR)) {
*flags |= env->sregs[CPENABLE] << XTENSA_TBFLAG_CPENABLE_SHIFT;
}
if (ENV_GET_CPU(env)->singlestep_enabled && env->exception_taken) {
*flags |= XTENSA_TBFLAG_EXCEPTION;
}
}
#include "exec/cpu-all.h"

View file

@ -96,6 +96,9 @@ static void tb_invalidate_virtual_addr(CPUXtensaState *env, uint32_t vaddr)
void HELPER(exception)(CPUXtensaState *env, uint32_t excp)
{
env->exception_index = excp;
if (excp == EXCP_DEBUG) {
env->exception_taken = 0;
}
cpu_loop_exit(env);
}

View file

@ -2918,8 +2918,7 @@ void gen_intermediate_code_internal(XtensaCPU *cpu,
gen_tb_start();
if (cs->singlestep_enabled && env->exception_taken) {
env->exception_taken = 0;
if (tb->flags & XTENSA_TBFLAG_EXCEPTION) {
tcg_gen_movi_i32(cpu_pc, dc.pc);
gen_exception(&dc, EXCP_DEBUG);
}