ppc: Don't generate dead code on unconditional branches

We are always generating the "else" case of the condition even when
generating an unconditional branch that will never hit it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Benjamin Herrenschmidt 2016-07-31 15:13:09 +10:00 committed by David Gibson
parent 4f5d326046
commit accc60c47c
1 changed files with 9 additions and 5 deletions

View File

@ -3480,8 +3480,10 @@ static inline void gen_bcond(DisasContext *ctx, int type)
} else {
gen_goto_tb(ctx, 0, li);
}
gen_set_label(l1);
gen_goto_tb(ctx, 1, ctx->nip);
if ((bo & 0x14) != 0x14) {
gen_set_label(l1);
gen_goto_tb(ctx, 1, ctx->nip);
}
} else {
if (NARROW_MODE(ctx)) {
tcg_gen_andi_tl(cpu_nip, target, (uint32_t)~3);
@ -3489,9 +3491,11 @@ static inline void gen_bcond(DisasContext *ctx, int type)
tcg_gen_andi_tl(cpu_nip, target, ~3);
}
tcg_gen_exit_tb(0);
gen_set_label(l1);
gen_update_nip(ctx, ctx->nip);
tcg_gen_exit_tb(0);
if ((bo & 0x14) != 0x14) {
gen_set_label(l1);
gen_update_nip(ctx, ctx->nip);
tcg_gen_exit_tb(0);
}
}
if (type == BCOND_LR || type == BCOND_CTR || type == BCOND_TAR) {
tcg_temp_free(target);