target/ppc: Replace POWERPC_EXCP_BRANCH with DISAS_NORETURN

The translation of branch instructions always results in exit from
the TB. Remove the synthetic "exception" after no more uses.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210517205025.3777947-4-matheus.ferst@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Richard Henderson 2021-05-17 17:50:05 -03:00 committed by David Gibson
parent d736de8ff6
commit 6086c751c3
3 changed files with 2 additions and 11 deletions

View File

@ -423,9 +423,6 @@ void cpu_loop(CPUPPCState *env)
cpu_abort(cs, "Maintenance exception while in user mode. "
"Aborting\n");
break;
case POWERPC_EXCP_BRANCH: /* branch instruction: */
/* We just stopped because of a branch. Go on */
break;
case POWERPC_EXCP_SYSCALL_USER:
/* system call in user-mode emulation */
/* WARNING:

View File

@ -131,8 +131,6 @@ enum {
POWERPC_EXCP_SYSCALL_VECTORED = 102, /* scv exception */
/* EOL */
POWERPC_EXCP_NB = 103,
/* QEMU exceptions: used internally during code translation */
POWERPC_EXCP_BRANCH = 0x201, /* branch instruction */
/* QEMU exceptions: special cases we want to stop translation */
POWERPC_EXCP_SYSCALL_USER = 0x203, /* System call in user mode only */
};

View File

@ -4692,7 +4692,6 @@ static void gen_b(DisasContext *ctx)
{
target_ulong li, target;
ctx->exception = POWERPC_EXCP_BRANCH;
/* sign extend LI */
li = LI(ctx->opcode);
li = (li ^ 0x02000000) - 0x02000000;
@ -4706,6 +4705,7 @@ static void gen_b(DisasContext *ctx)
}
gen_update_cfar(ctx, ctx->cia);
gen_goto_tb(ctx, 0, target);
ctx->base.is_jmp = DISAS_NORETURN;
}
#define BCOND_IM 0
@ -4718,7 +4718,6 @@ static void gen_bcond(DisasContext *ctx, int type)
uint32_t bo = BO(ctx->opcode);
TCGLabel *l1;
TCGv target;
ctx->exception = POWERPC_EXCP_BRANCH;
if (type == BCOND_LR || type == BCOND_CTR || type == BCOND_TAR) {
target = tcg_temp_local_new();
@ -4825,6 +4824,7 @@ static void gen_bcond(DisasContext *ctx, int type)
gen_set_label(l1);
gen_goto_tb(ctx, 1, ctx->base.pc_next);
}
ctx->base.is_jmp = DISAS_NORETURN;
}
static void gen_bc(DisasContext *ctx)
@ -9102,7 +9102,6 @@ static void ppc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
/* Check trace mode exceptions */
if (unlikely(ctx->singlestep_enabled & CPU_SINGLE_STEP &&
(ctx->base.pc_next <= 0x100 || ctx->base.pc_next > 0xF00) &&
ctx->exception != POWERPC_EXCP_BRANCH &&
ctx->base.is_jmp != DISAS_NORETURN)) {
uint32_t excp = gen_prep_dbgex(ctx);
gen_exception_nip(ctx, excp, ctx->base.pc_next);
@ -9118,9 +9117,6 @@ static void ppc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
switch (ctx->exception) {
case POWERPC_EXCP_NONE:
break;
case POWERPC_EXCP_BRANCH:
ctx->base.is_jmp = DISAS_NORETURN;
break;
default:
/* Every other ctx->exception should have set NORETURN. */
g_assert_not_reached();