[Qemu-devel] [RFC][PATCH v0 4/8] Calculate NEXT_CALL liveness information.

[Kirill Batuzov]

Keep track of where is the next call for each TCG operation.

Signed-off-by: Kirill Batuzov <address@hidden>
---
 tcg/tcg.c |   11 +++++++++++
 tcg/tcg.h |    2 ++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/tcg/tcg.c b/tcg/tcg.c
index 61689e2..799b245 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -1212,6 +1212,9 @@ static void tcg_liveness_analysis(TCGContext *s)
     uint8_t *dead_temps;
     int *temp_next_use = NULL;
     unsigned int dead_iargs;
+#ifdef USE_ADVANCED_REGALLOC
+    int last_call;
+#endif
 
     gen_opc_ptr++; /* skip end */
 
@@ -1223,6 +1226,8 @@ static void tcg_liveness_analysis(TCGContext *s)
     nb_args = gen_opparam_ptr - gen_opparam_buf;
     s->param_next_use = tcg_malloc(nb_args * sizeof(s->param_next_use[0]));
     next_use_ptr = s->param_next_use + nb_args;
+    last_call = nb_ops + 1;
+    s->next_call = tcg_malloc(nb_ops * sizeof(s->next_call[0]));
 #endif
     
     dead_temps = tcg_malloc(s->nb_temps);
@@ -1237,6 +1242,12 @@ static void tcg_liveness_analysis(TCGContext *s)
     while (op_index >= 0) {
         op = gen_opc_buf[op_index];
         def = &tcg_op_defs[op];
+#ifdef USE_ADVANCED_REGALLOC
+        s->next_call[op_index] = last_call;
+        if (def->flags & TCG_OPF_CALL_CLOBBER) {
+            last_call = op_index;
+        }
+#endif
         switch(op) {
         case INDEX_op_call:
             {
diff --git a/tcg/tcg.h b/tcg/tcg.h
index d8bfa2c..9ff519e 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -290,6 +290,8 @@ struct TCGContext {
                                 corresponding input argument is dead */
     int *param_next_use; /* for each operation argument tells where it's
                             next used is (USE_ADVANCED_REGALLOC only) */
+    int *next_call; /* for each operation tells where next CALL operation
+                        occurs */
     
     /* tells in which temporary a given register is. It does not take
        into account fixed registers */
-- 
1.7.4.1