target/microblaze: Replace delayed_branch with tb_flags_to_set

The multi-stage counter can be replaced by clearing D_FLAG,
the or'ing in tb_flags_to_set.  The jump then happens when
D_FLAG is finally cleared.

Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2020-08-22 08:25:39 -07:00
parent 6f9642d7d7
commit 1e521ce3b0

View File

@ -73,7 +73,6 @@ typedef struct DisasContext {
uint16_t imm;
unsigned int cpustate_changed;
unsigned int delayed_branch;
unsigned int tb_flags;
unsigned int tb_flags_to_set;
int mem_index;
@ -1328,10 +1327,9 @@ static void eval_cond_jmp(DisasContext *dc, TCGv_i32 pc_true, TCGv_i32 pc_false)
static void dec_setup_dslot(DisasContext *dc)
{
dc->delayed_branch = 2;
dc->tb_flags |= D_FLAG;
dc->tb_flags_to_set |= D_FLAG;
if (dc->type_b && (dc->tb_flags & IMM_FLAG)) {
dc->tb_flags |= BIMM_FLAG;
dc->tb_flags_to_set |= BIMM_FLAG;
}
}
@ -1343,7 +1341,6 @@ static void dec_bcc(DisasContext *dc)
cc = EXTRACT_FIELD(dc->ir, 21, 23);
dslot = dc->ir & (1 << 25);
dc->delayed_branch = 1;
if (dslot) {
dec_setup_dslot(dc);
}
@ -1419,7 +1416,6 @@ static void dec_br(DisasContext *dc)
}
}
dc->delayed_branch = 1;
if (dslot) {
dec_setup_dslot(dc);
}
@ -1633,8 +1629,7 @@ static void mb_tr_init_disas_context(DisasContextBase *dcb, CPUState *cs)
dc->cpu = cpu;
dc->tb_flags = dc->base.tb->flags;
dc->delayed_branch = !!(dc->tb_flags & D_FLAG);
dc->jmp = dc->delayed_branch ? JMP_INDIRECT : JMP_NOJMP;
dc->jmp = dc->tb_flags & D_FLAG ? JMP_INDIRECT : JMP_NOJMP;
dc->cpustate_changed = 0;
dc->abort_at_next_insn = 0;
dc->ext_imm = dc->base.tb->cs_base;
@ -1705,11 +1700,11 @@ static void mb_tr_translate_insn(DisasContextBase *dcb, CPUState *cs)
tcg_gen_discard_i32(cpu_imm);
}
dc->tb_flags &= ~IMM_FLAG;
dc->tb_flags &= ~(IMM_FLAG | BIMM_FLAG | D_FLAG);
dc->tb_flags |= dc->tb_flags_to_set;
dc->base.pc_next += 4;
if (dc->delayed_branch && --dc->delayed_branch == 0) {
if (dc->jmp != JMP_NOJMP && !(dc->tb_flags & D_FLAG)) {
if (dc->tb_flags & DRTI_FLAG) {
do_rti(dc);
}
@ -1719,8 +1714,6 @@ static void mb_tr_translate_insn(DisasContextBase *dcb, CPUState *cs)
if (dc->tb_flags & DRTE_FLAG) {
do_rte(dc);
}
/* Clear the delay slot flag. */
dc->tb_flags &= ~D_FLAG;
dc->base.is_jmp = DISAS_JUMP;
}