Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/xtensa/translate.c | 229 ++++++++++++++++++++------------------
 1 file changed, 122 insertions(+), 107 deletions(-)

diff --git a/target/xtensa/translate.c b/target/xtensa/translate.c
index 45f32dc71f..9de45e4be4 100644
--- a/target/xtensa/translate.c
+++ b/target/xtensa/translate.c
@@ -1048,148 +1048,163 @@ static void gen_ibreak_check(CPUXtensaState *env, DisasContext *dc)
     }
 }
 
-void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
+static void xtensa_tr_init_disas_context(DisasContextBase *dcbase,
+                                         CPUState *cpu)
 {
-    CPUXtensaState *env = cs->env_ptr;
-    DisasContext dc1, *dc = &dc1;
-    int insn_count = 0;
-    int max_insns = tb_cflags(tb) & CF_COUNT_MASK;
-    uint32_t pc_start = tb->pc;
-    uint32_t page_start = pc_start & TARGET_PAGE_MASK;
-
-    if (max_insns == 0) {
-        max_insns = CF_COUNT_MASK;
-    }
-    if (max_insns > TCG_MAX_INSNS) {
-        max_insns = TCG_MAX_INSNS;
-    }
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+    CPUXtensaState *env = cpu->env_ptr;
+    uint32_t tb_flags = dc->base.tb->flags;
 
     dc->config = env->config;
-    dc->base.singlestep_enabled = cs->singlestep_enabled;
-    dc->base.tb = tb;
-    dc->pc = pc_start;
-    dc->ring = tb->flags & XTENSA_TBFLAG_RING_MASK;
-    dc->cring = (tb->flags & XTENSA_TBFLAG_EXCM) ? 0 : dc->ring;
+    dc->pc = dc->base.pc_first;
+    dc->ring = tb_flags & XTENSA_TBFLAG_RING_MASK;
+    dc->cring = (tb_flags & XTENSA_TBFLAG_EXCM) ? 0 : dc->ring;
     dc->lbeg = env->sregs[LBEG];
     dc->lend = env->sregs[LEND];
-    dc->base.is_jmp = DISAS_NEXT;
-    dc->debug = tb->flags & XTENSA_TBFLAG_DEBUG;
-    dc->icount = tb->flags & XTENSA_TBFLAG_ICOUNT;
-    dc->cpenable = (tb->flags & XTENSA_TBFLAG_CPENABLE_MASK) >>
+    dc->debug = tb_flags & XTENSA_TBFLAG_DEBUG;
+    dc->icount = tb_flags & XTENSA_TBFLAG_ICOUNT;
+    dc->cpenable = (tb_flags & XTENSA_TBFLAG_CPENABLE_MASK) >>
         XTENSA_TBFLAG_CPENABLE_SHIFT;
-    dc->window = ((tb->flags & XTENSA_TBFLAG_WINDOW_MASK) >>
+    dc->window = ((tb_flags & XTENSA_TBFLAG_WINDOW_MASK) >>
                  XTENSA_TBFLAG_WINDOW_SHIFT);
 
     if (dc->config->isa) {
         dc->insnbuf = xtensa_insnbuf_alloc(dc->config->isa);
         dc->slotbuf = xtensa_insnbuf_alloc(dc->config->isa);
     }
-
     init_sar_tracker(dc);
+}
+
+static void xtensa_tr_tb_start(DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
     if (dc->icount) {
         dc->next_icount = tcg_temp_local_new_i32();
     }
+}
 
-    gen_tb_start(tb);
+static void xtensa_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
+{
+    tcg_gen_insn_start(dcbase->pc_next);
+}
 
-    if ((tb_cflags(tb) & CF_USE_ICOUNT) &&
-        (tb->flags & XTENSA_TBFLAG_YIELD)) {
-        tcg_gen_insn_start(dc->pc);
-        ++insn_count;
+static bool xtensa_tr_breakpoint_check(DisasContextBase *dcbase, CPUState *cpu,
+                                       const CPUBreakpoint *bp)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    tcg_gen_movi_i32(cpu_pc, dc->base.pc_next);
+    gen_exception(dc, EXCP_DEBUG);
+    dc->base.is_jmp = DISAS_NORETURN;
+    /* The address covered by the breakpoint must be included in
+       [tb->pc, tb->pc + tb->size) in order to for it to be
+       properly cleared -- thus we increment the PC here so that
+       the logic setting tb->size below does the right thing.  */
+    dc->base.pc_next += 2;
+    return true;
+}
+
+static void xtensa_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+    CPUXtensaState *env = cpu->env_ptr;
+    target_ulong page_start;
+
+    /* These two conditions only apply to the first insn in the TB,
+       but this is the first TranslateOps hook that allows exiting.  */
+    if ((tb_cflags(dc->base.tb) & CF_USE_ICOUNT)
+        && (dc->base.tb->flags & XTENSA_TBFLAG_YIELD)) {
         gen_exception(dc, EXCP_YIELD);
         dc->base.is_jmp = DISAS_NORETURN;
-        goto done;
+        return;
     }
-    if (tb->flags & XTENSA_TBFLAG_EXCEPTION) {
-        tcg_gen_insn_start(dc->pc);
-        ++insn_count;
+    if (dc->base.tb->flags & XTENSA_TBFLAG_EXCEPTION) {
         gen_exception(dc, EXCP_DEBUG);
         dc->base.is_jmp = DISAS_NORETURN;
-        goto done;
+        return;
     }
 
-    do {
-        tcg_gen_insn_start(dc->pc);
-        ++insn_count;
-
-        if (unlikely(cpu_breakpoint_test(cs, dc->pc, BP_ANY))) {
-            tcg_gen_movi_i32(cpu_pc, dc->pc);
-            gen_exception(dc, EXCP_DEBUG);
-            dc->base.is_jmp = DISAS_NORETURN;
-            /* The address covered by the breakpoint must be included in
-               [tb->pc, tb->pc + tb->size) in order to for it to be
-               properly cleared -- thus we increment the PC here so that
-               the logic setting tb->size below does the right thing.  */
-            dc->pc += 2;
-            break;
-        }
-
-        if (insn_count == max_insns && (tb_cflags(tb) & CF_LAST_IO)) {
-            gen_io_start();
-        }
-
-        if (dc->icount) {
-            TCGLabel *label = gen_new_label();
-
-            tcg_gen_addi_i32(dc->next_icount, cpu_SR[ICOUNT], 1);
-            tcg_gen_brcondi_i32(TCG_COND_NE, dc->next_icount, 0, label);
-            tcg_gen_mov_i32(dc->next_icount, cpu_SR[ICOUNT]);
-            if (dc->debug) {
-                gen_debug_exception(dc, DEBUGCAUSE_IC);
-            }
-            gen_set_label(label);
-        }
-
-        if (dc->debug) {
-            gen_ibreak_check(env, dc);
-        }
-
-        disas_xtensa_insn(env, dc);
-        if (dc->icount) {
-            tcg_gen_mov_i32(cpu_SR[ICOUNT], dc->next_icount);
-        }
-        if (dc->base.singlestep_enabled) {
-            tcg_gen_movi_i32(cpu_pc, dc->pc);
-            gen_exception(dc, EXCP_DEBUG);
-            break;
-        }
-    } while (dc->base.is_jmp == DISAS_NEXT &&
-             insn_count < max_insns &&
-             dc->pc - page_start < TARGET_PAGE_SIZE &&
-             dc->pc - page_start + xtensa_insn_len(env, dc) <= TARGET_PAGE_SIZE
-             && !tcg_op_buf_full());
-done:
-    reset_sar_tracker(dc);
     if (dc->icount) {
-        tcg_temp_free(dc->next_icount);
+        TCGLabel *label = gen_new_label();
+
+        tcg_gen_addi_i32(dc->next_icount, cpu_SR[ICOUNT], 1);
+        tcg_gen_brcondi_i32(TCG_COND_NE, dc->next_icount, 0, label);
+        tcg_gen_mov_i32(dc->next_icount, cpu_SR[ICOUNT]);
+        if (dc->debug) {
+            gen_debug_exception(dc, DEBUGCAUSE_IC);
+        }
+        gen_set_label(label);
     }
+
+    if (dc->debug) {
+        gen_ibreak_check(env, dc);
+    }
+
+    disas_xtensa_insn(env, dc);
+
+    if (dc->icount) {
+        tcg_gen_mov_i32(cpu_SR[ICOUNT], dc->next_icount);
+    }
+
+    /* End the TB if the next insn will cross into the next page.  */
+    page_start = dc->base.pc_first & TARGET_PAGE_MASK;
+    if (dc->base.is_jmp == DISAS_NEXT &&
+        dc->pc - page_start < TARGET_PAGE_SIZE &&
+        dc->pc - page_start + xtensa_insn_len(env, dc) <= TARGET_PAGE_SIZE) {
+        dc->base.is_jmp = DISAS_TOO_MANY;
+    }
+}
+
+static void xtensa_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    reset_sar_tracker(dc);
     if (dc->config->isa) {
         xtensa_insnbuf_free(dc->config->isa, dc->insnbuf);
         xtensa_insnbuf_free(dc->config->isa, dc->slotbuf);
     }
-
-    if (tb_cflags(tb) & CF_LAST_IO) {
-        gen_io_end();
+    if (dc->icount) {
+        tcg_temp_free(dc->next_icount);
     }
 
-    if (dc->base.is_jmp == DISAS_NEXT) {
-        gen_jumpi(dc, dc->pc, 0);
+    switch (dc->base.is_jmp) {
+    case DISAS_NORETURN:
+        break;
+    case DISAS_TOO_MANY:
+        if (dc->base.singlestep_enabled) {
+            tcg_gen_movi_i32(cpu_pc, dc->pc);
+            gen_exception(dc, EXCP_DEBUG);
+        } else {
+            gen_jumpi(dc, dc->pc, 0);
+        }
+        break;
+    default:
+        g_assert_not_reached();
     }
-    gen_tb_end(tb, insn_count);
+}
 
-#ifdef DEBUG_DISAS
-    if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
-        && qemu_log_in_addr_range(pc_start)) {
-        qemu_log_lock();
-        qemu_log("----------------\n");
-        qemu_log("IN: %s\n", lookup_symbol(pc_start));
-        log_target_disas(cs, pc_start, dc->pc - pc_start);
-        qemu_log("\n");
-        qemu_log_unlock();
-    }
-#endif
-    tb->size = dc->pc - pc_start;
-    tb->icount = insn_count;
+static void xtensa_tr_disas_log(const DisasContextBase *dcbase, CPUState *cpu)
+{
+    qemu_log("IN: %s\n", lookup_symbol(dcbase->pc_first));
+    log_target_disas(cpu, dcbase->pc_first, dcbase->tb->size);
+}
+
+static const TranslatorOps xtensa_translator_ops = {
+    .init_disas_context = xtensa_tr_init_disas_context,
+    .tb_start           = xtensa_tr_tb_start,
+    .insn_start         = xtensa_tr_insn_start,
+    .breakpoint_check   = xtensa_tr_breakpoint_check,
+    .translate_insn     = xtensa_tr_translate_insn,
+    .tb_stop            = xtensa_tr_tb_stop,
+    .disas_log          = xtensa_tr_disas_log,
+};
+
+void gen_intermediate_code(CPUState *cpu, TranslationBlock *tb)
+{
+    DisasContext dc = {};
+    translator_loop(&xtensa_translator_ops, &dc.base, cpu, tb);
 }
 
 void xtensa_cpu_dump_state(CPUState *cs, FILE *f,
-- 
2.17.0

On Sat, May 12, 2018 at 10:57 AM, Richard Henderson
<richard.henderson@linaro.org> wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/xtensa/translate.c | 229 ++++++++++++++++++++------------------
>  1 file changed, 122 insertions(+), 107 deletions(-)

This patch breaks tests/tcg/xtensa/test_mmu.S cross_page_tb test.
Looking at it...

-- 
Thanks.
-- Max

On Sat, May 12, 2018 at 10:57 AM, Richard Henderson
<richard.henderson@linaro.org> wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/xtensa/translate.c | 229 ++++++++++++++++++++------------------
>  1 file changed, 122 insertions(+), 107 deletions(-)

[...]

> -    } while (dc->base.is_jmp == DISAS_NEXT &&
> -             insn_count < max_insns &&
> -             dc->pc - page_start < TARGET_PAGE_SIZE &&
> -             dc->pc - page_start + xtensa_insn_len(env, dc) <= TARGET_PAGE_SIZE
> -             && !tcg_op_buf_full());
> -done:

[...]

> +    /* End the TB if the next insn will cross into the next page.  */
> +    page_start = dc->base.pc_first & TARGET_PAGE_MASK;
> +    if (dc->base.is_jmp == DISAS_NEXT &&
> +        dc->pc - page_start < TARGET_PAGE_SIZE &&
> +        dc->pc - page_start + xtensa_insn_len(env, dc) <= TARGET_PAGE_SIZE) {

Originally it was the condition to continue translation.
To end the TB when the next instruction will cross into the next page the
condition must be changed to something like

    if (dc->base.is_jmp == DISAS_NEXT &&
        (dc->pc - page_start >= TARGET_PAGE_SIZE ||
         dc->pc - page_start + xtensa_insn_len(env, dc) > TARGET_PAGE_SIZE)) {

With that change all tests in tests/tcg/xtensa are passing.
I'll play with it some more...

-- 
Thanks.
-- Max