[Qemu-devel] [PATCH v13 22/26] target/arm: [tcg] Port to tb_stop

["Lluís Vilanova" <vilanova@ac.upc.edu>]

Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
---
 target/arm/translate.c |  165 +++++++++++++++++++++++++-----------------------
 target/arm/translate.h |    1 
 2 files changed, 87 insertions(+), 79 deletions(-)

diff --git a/target/arm/translate.c b/target/arm/translate.c
index c60be757dc..f221cbee5d 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -11967,7 +11967,7 @@ static target_ulong arm_tr_translate_insn(DisasContextBase *dcbase,
         assert(dc->base.num_insns == 1);
         gen_exception(EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0),
                       default_exception_el(dc));
-        dc->base.is_jmp = DISAS_SKIP;
+        dc->base.is_jmp = DISAS_NORETURN;
         return dc->pc;
     }
 
@@ -12019,87 +12019,17 @@ static target_ulong arm_tr_translate_insn(DisasContextBase *dcbase,
     return dc->pc;
 }
 
-/* generate intermediate code for basic block 'tb'.  */
-void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
+static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
 {
-    DisasContext dc1, *dc = &dc1;
-    int max_insns;
-
-    /* generate intermediate code */
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
 
-    /* The A64 decoder has its own top level loop, because it doesn't need
-     * the A32/T32 complexity to do with conditional execution/IT blocks/etc.
-     */
-    if (ARM_TBFLAG_AARCH64_STATE(tb->flags)) {
-        gen_intermediate_code_a64(&dc->base, cs, tb);
+    if (dc->base.is_jmp == DISAS_NORETURN) {
         return;
     }
 
-    dc->base.tb = tb;
-    dc->base.pc_first = dc->base.tb->pc;
-    dc->base.pc_next = dc->base.pc_first;
-    dc->base.is_jmp = DISAS_NEXT;
-    dc->base.num_insns = 0;
-    dc->base.singlestep_enabled = cs->singlestep_enabled;
-    arm_tr_init_disas_context(&dc->base, cs);
-
-    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;
-    }
-
-    gen_tb_start(tb);
-
-    tcg_clear_temp_count();
-    arm_tr_tb_start(&dc->base, cs, &max_insns);
-
-    do {
-        dc->base.num_insns++;
-        arm_tr_insn_start(&dc->base, cs);
-
-        if (unlikely(!QTAILQ_EMPTY(&cs->breakpoints))) {
-            CPUBreakpoint *bp;
-            QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
-                if (bp->pc == dc->base.pc_next) {
-                    if (arm_tr_breakpoint_check(&dc->base, cs, bp)) {
-                        break;
-                    }
-                }
-            }
-
-            if (dc->base.is_jmp == DISAS_NORETURN) {
-                break;
-            }
-        }
-
-        if (dc->base.num_insns == max_insns && (tb->cflags & CF_LAST_IO)) {
-            gen_io_start();
-        }
-
-        dc->base.pc_next = arm_tr_translate_insn(&dc->base, cs);
-
-        if (tcg_check_temp_count()) {
-            fprintf(stderr, "TCG temporary leak before "TARGET_FMT_lx"\n",
-                    dc->pc);
-        }
-
-        if (!dc->base.is_jmp && (tcg_op_buf_full() || singlestep ||
-                            dc->base.num_insns >= max_insns)) {
-            dc->base.is_jmp = DISAS_TOO_MANY;
-        }
-    } while (!dc->base.is_jmp);
-
-    if (dc->base.is_jmp != DISAS_SKIP) {
-    if (tb->cflags & CF_LAST_IO) {
-        if (dc->condjmp) {
-            /* FIXME:  This can theoretically happen with self-modifying
-               code.  */
-            cpu_abort(cs, "IO on conditional branch instruction");
-        }
-        gen_io_end();
+    if (dc->base.tb->cflags & CF_LAST_IO && dc->condjmp) {
+        /* FIXME: This can theoretically happen with self-modifying code. */
+        cpu_abort(cpu, "IO on conditional branch instruction");
     }
 
     /* At this stage dc->condjmp will only be set when the skipped
@@ -12203,9 +12133,88 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
             gen_goto_tb(dc, 1, dc->pc);
         }
     }
+}
+
+/* generate intermediate code for basic block 'tb'.  */
+void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
+{
+    DisasContext dc1, *dc = &dc1;
+    int max_insns;
+
+    /* generate intermediate code */
+
+    /* The A64 decoder has its own top level loop, because it doesn't need
+     * the A32/T32 complexity to do with conditional execution/IT blocks/etc.
+     */
+    if (ARM_TBFLAG_AARCH64_STATE(tb->flags)) {
+        gen_intermediate_code_a64(&dc->base, cs, tb);
+        return;
+    }
+
+    dc->base.tb = tb;
+    dc->base.pc_first = dc->base.tb->pc;
+    dc->base.pc_next = dc->base.pc_first;
+    dc->base.is_jmp = DISAS_NEXT;
+    dc->base.num_insns = 0;
+    dc->base.singlestep_enabled = cs->singlestep_enabled;
+    arm_tr_init_disas_context(&dc->base, cs);
+
+
+    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;
+    }
+
+    gen_tb_start(tb);
+
+    tcg_clear_temp_count();
+    arm_tr_tb_start(&dc->base, cs, &max_insns);
+
+    do {
+        dc->base.num_insns++;
+        arm_tr_insn_start(&dc->base, cs);
+
+        if (unlikely(!QTAILQ_EMPTY(&cs->breakpoints))) {
+            CPUBreakpoint *bp;
+            QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
+                if (bp->pc == dc->base.pc_next) {
+                    if (arm_tr_breakpoint_check(&dc->base, cs, bp)) {
+                        break;
+                    }
+                }
+            }
+
+            if (dc->base.is_jmp == DISAS_NORETURN) {
+                break;
+            }
+        }
+
+        if (dc->base.num_insns == max_insns && (tb->cflags & CF_LAST_IO)) {
+            gen_io_start();
+        }
+
+        dc->base.pc_next = arm_tr_translate_insn(&dc->base, cs);
+
+        if (tcg_check_temp_count()) {
+            fprintf(stderr, "TCG temporary leak before "TARGET_FMT_lx"\n",
+                    dc->pc);
+        }
+
+        if (!dc->base.is_jmp && (tcg_op_buf_full() || singlestep ||
+                            dc->base.num_insns >= max_insns)) {
+            dc->base.is_jmp = DISAS_TOO_MANY;
+        }
+    } while (!dc->base.is_jmp);
+
+    arm_tr_tb_stop(&dc->base, cs);
+
+    if (dc->base.tb->cflags & CF_LAST_IO) {
+        gen_io_end();
     }
 
-done_generating:
     gen_tb_end(tb, dc->base.num_insns);
 
 #ifdef DEBUG_DISAS
diff --git a/target/arm/translate.h b/target/arm/translate.h
index 83e56dcb08..720cb102e3 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -149,7 +149,6 @@ static void disas_set_insn_syndrome(DisasContext *s, uint32_t syn)
  * as opposed to attempting to use lookup_and_goto_ptr.
  */
 #define DISAS_EXIT DISAS_TARGET_11
-#define DISAS_SKIP DISAS_TARGET_12
 
 #ifdef TARGET_AARCH64
 void a64_translate_init(void);