[Qemu-devel] [PATCH 2/2] target/openrisc: convert to TranslatorOps

[Emilio G. Cota]

Notes:

- Changed the num_insns test in tb_start to check for
  dc->base.num_insns > 1, since when tb_start is first
  called in a TB, base.num_insns is already set to 1.

- Removed DISAS_NEXT from the switch on tb_stop; use DISAS_TOO_MANY
  instead.

- Added an assert_not_reached on tb_stop for DISAS_NEXT and the default
  case.

- Merged the two separate log_target_disas calls into the disas_log op.

Signed-off-by: Emilio G. Cota <address@hidden>
---
 target/openrisc/translate.c | 168 ++++++++++++++++++++++----------------------
 1 file changed, 85 insertions(+), 83 deletions(-)

diff --git a/target/openrisc/translate.c b/target/openrisc/translate.c
index 0450144..4af4569 100644
--- a/target/openrisc/translate.c
+++ b/target/openrisc/translate.c
@@ -49,6 +49,7 @@ typedef struct DisasContext {
     uint32_t mem_idx;
     uint32_t tb_flags;
     uint32_t delayed_branch;
+    uint32_t next_page_start;
 } DisasContext;
 
 static TCGv cpu_sr;
@@ -1519,46 +1520,23 @@ static void disas_openrisc_insn(DisasContext *dc, 
OpenRISCCPU *cpu)
     }
 }
 
-void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb)
+static int openrisc_tr_init_disas_context(DisasContextBase *dcbase,
+                                          CPUState *cs, int max_insns)
 {
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
     CPUOpenRISCState *env = cs->env_ptr;
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-    struct DisasContext ctx, *dc = &ctx;
-    uint32_t pc_start;
-    uint32_t next_page_start;
-    int num_insns;
-    int max_insns;
 
-    pc_start = tb->pc;
-
-    dc->base.tb = tb;
-    dc->base.singlestep_enabled = cs->singlestep_enabled;
-    dc->base.pc_next = pc_start;
-    dc->base.is_jmp = DISAS_NEXT;
-
-    dc->mem_idx = cpu_mmu_index(&cpu->env, false);
+    dc->mem_idx = cpu_mmu_index(env, false);
     dc->tb_flags = dc->base.tb->flags;
     dc->delayed_branch = (dc->tb_flags & TB_FLAGS_DFLAG) != 0;
+    dc->next_page_start = (dc->base.pc_first & TARGET_PAGE_MASK) +
+        TARGET_PAGE_SIZE;
+    return max_insns;
+}
 
-    next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
-    num_insns = 0;
-    max_insns = tb_cflags(tb) & CF_COUNT_MASK;
-
-    if (max_insns == 0) {
-        max_insns = CF_COUNT_MASK;
-    }
-    if (max_insns > TCG_MAX_INSNS) {
-        max_insns = TCG_MAX_INSNS;
-    }
-
-    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));
-    }
-
-    gen_tb_start(tb);
+static void openrisc_tr_tb_start(DisasContextBase *db, CPUState *cs)
+{
+    DisasContext *dc = container_of(db, DisasContext, base);
 
     /* Allow the TCG optimizer to see that R0 == 0,
        when it's true, which is the common case.  */
@@ -1567,50 +1545,60 @@ void gen_intermediate_code(CPUState *cs, struct 
TranslationBlock *tb)
     } else {
         cpu_R[0] = cpu_R0;
     }
+}
+
+static void openrisc_tr_insn_start(DisasContextBase *dcbase, CPUState *cs)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
 
-    do {
-        tcg_gen_insn_start(dc->base.pc_next, (dc->delayed_branch ? 1 : 0)
-                          | (num_insns ? 2 : 0));
-        num_insns++;
+    tcg_gen_insn_start(dc->base.pc_next, (dc->delayed_branch ? 1 : 0)
+                       | (dc->base.num_insns > 1 ? 2 : 0));
+}
 
-        if (unlikely(cpu_breakpoint_test(cs, dc->base.pc_next, BP_ANY))) {
-            tcg_gen_movi_tl(cpu_pc, dc->base.pc_next);
-            gen_exception(dc, EXCP_DEBUG);
+static bool openrisc_tr_breakpoint_check(DisasContextBase *dcbase, CPUState 
*cs,
+                                         const CPUBreakpoint *bp)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    tcg_gen_movi_tl(cpu_pc, dc->base.pc_next);
+    gen_exception(dc, EXCP_DEBUG);
+    dc->base.is_jmp = DISAS_UPDATE;
+    /* 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 += 4;
+    return true;
+}
+
+static void openrisc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+    OpenRISCCPU *cpu = OPENRISC_CPU(cs);
+
+    disas_openrisc_insn(dc, cpu);
+    dc->base.pc_next += 4;
+
+    /* delay slot */
+    if (dc->delayed_branch) {
+        dc->delayed_branch--;
+        if (!dc->delayed_branch) {
+            tcg_gen_mov_tl(cpu_pc, jmp_pc);
+            tcg_gen_discard_tl(jmp_pc);
             dc->base.is_jmp = DISAS_UPDATE;
-            /* 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 += 4;
-            break;
+            return;
         }
+    }
 
-        if (num_insns == max_insns && (tb_cflags(tb) & CF_LAST_IO)) {
-            gen_io_start();
-        }
-        disas_openrisc_insn(dc, cpu);
-        dc->base.pc_next += 4;
-
-        /* delay slot */
-        if (dc->delayed_branch) {
-            dc->delayed_branch--;
-            if (!dc->delayed_branch) {
-                tcg_gen_mov_tl(cpu_pc, jmp_pc);
-                tcg_gen_discard_tl(jmp_pc);
-                dc->base.is_jmp = DISAS_UPDATE;
-                break;
-            }
-        }
-    } while (!dc->base.is_jmp
-             && !tcg_op_buf_full()
-             && !dc->base.singlestep_enabled
-             && !singlestep
-             && (dc->base.pc_next < next_page_start)
-             && num_insns < max_insns);
-
-    if (tb_cflags(tb) & CF_LAST_IO) {
-        gen_io_end();
+    if (dc->base.is_jmp == DISAS_NEXT &&
+        dc->base.pc_next >= dc->next_page_start) {
+        dc->base.is_jmp = DISAS_TOO_MANY;
     }
+}
+
+static void openrisc_tr_tb_stop(DisasContextBase *dcbase, CPUState *cs)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
 
     if ((dc->tb_flags & TB_FLAGS_DFLAG ? 1 : 0) != (dc->delayed_branch != 0)) {
         tcg_gen_movi_i32(cpu_dflag, dc->delayed_branch != 0);
@@ -1625,10 +1613,9 @@ void gen_intermediate_code(CPUState *cs, struct 
TranslationBlock *tb)
         gen_exception(dc, EXCP_DEBUG);
     } else {
         switch (dc->base.is_jmp) {
-        case DISAS_NEXT:
+        case DISAS_TOO_MANY:
             gen_goto_tb(dc, 0, dc->base.pc_next);
             break;
-        default:
         case DISAS_JUMP:
             break;
         case DISAS_UPDATE:
@@ -1639,20 +1626,35 @@ void gen_intermediate_code(CPUState *cs, struct 
TranslationBlock *tb)
         case DISAS_TB_JUMP:
             /* nothing more to generate */
             break;
+        default:
+            g_assert_not_reached();
         }
     }
+}
+
+static void openrisc_tr_disas_log(const DisasContextBase *dcbase, CPUState *cs)
+{
+    DisasContext *s = container_of(dcbase, DisasContext, base);
 
-    gen_tb_end(tb, num_insns);
+    qemu_log("IN: %s\n", lookup_symbol(s->base.pc_first));
+    log_target_disas(cs, s->base.pc_first, s->base.tb->size);
+}
 
-    tb->size = dc->base.pc_next - pc_start;
-    tb->icount = num_insns;
+static const TranslatorOps openrisc_tr_ops = {
+    .init_disas_context = openrisc_tr_init_disas_context,
+    .tb_start           = openrisc_tr_tb_start,
+    .insn_start         = openrisc_tr_insn_start,
+    .breakpoint_check   = openrisc_tr_breakpoint_check,
+    .translate_insn     = openrisc_tr_translate_insn,
+    .tb_stop            = openrisc_tr_tb_stop,
+    .disas_log          = openrisc_tr_disas_log,
+};
 
-    if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
-        && qemu_log_in_addr_range(pc_start)) {
-        log_target_disas(cs, pc_start, tb->size);
-        qemu_log("\n");
-        qemu_log_unlock();
-    }
+void gen_intermediate_code(CPUState *cs, struct TranslationBlock *tb)
+{
+    DisasContext ctx;
+
+    translator_loop(&openrisc_tr_ops, &ctx.base, cs, tb);
 }
 
 void openrisc_cpu_dump_state(CPUState *cs, FILE *f,
-- 
2.7.4