target/sh4: Consolidate end-of-TB tests

We can fold 3 different tests within the decode loop
into a more accurate computation of max_insns to start.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170718200255.31647-3-rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This commit is contained in:
Richard Henderson 2017-07-18 10:02:27 -10:00 committed by Aurelien Jarno
parent 92f1f83e34
commit 4448a83606

View File

@ -1830,17 +1830,28 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
ctx.features = env->features;
ctx.has_movcal = (ctx.tbflags & TB_FLAG_PENDING_MOVCA);
num_insns = 0;
max_insns = tb->cflags & CF_COUNT_MASK;
if (max_insns == 0) {
max_insns = CF_COUNT_MASK;
}
if (max_insns > TCG_MAX_INSNS) {
max_insns = TCG_MAX_INSNS;
max_insns = MIN(max_insns, TCG_MAX_INSNS);
/* Since the ISA is fixed-width, we can bound by the number
of instructions remaining on the page. */
num_insns = -(ctx.pc | TARGET_PAGE_MASK) / 2;
max_insns = MIN(max_insns, num_insns);
/* Single stepping means just that. */
if (ctx.singlestep_enabled || singlestep) {
max_insns = 1;
}
gen_tb_start(tb);
while (ctx.bstate == BS_NONE && !tcg_op_buf_full()) {
num_insns = 0;
while (ctx.bstate == BS_NONE
&& num_insns < max_insns
&& !tcg_op_buf_full()) {
tcg_gen_insn_start(ctx.pc, ctx.envflags);
num_insns++;
@ -1864,18 +1875,10 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
ctx.opcode = cpu_lduw_code(env, ctx.pc);
decode_opc(&ctx);
ctx.pc += 2;
if ((ctx.pc & (TARGET_PAGE_SIZE - 1)) == 0)
break;
if (cs->singlestep_enabled) {
break;
}
if (num_insns >= max_insns)
break;
if (singlestep)
break;
}
if (tb->cflags & CF_LAST_IO)
if (tb->cflags & CF_LAST_IO) {
gen_io_end();
}
if (cs->singlestep_enabled) {
gen_save_cpu_state(&ctx, true);
gen_helper_debug(cpu_env);