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Diffstat (limited to 'tcg')
-rw-r--r--tcg/tcg.c64
1 files changed, 37 insertions, 27 deletions
diff --git a/tcg/tcg.c b/tcg/tcg.c
index cfeeaf1e44..567ec87dad 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -1180,31 +1180,27 @@ static inline void tcg_set_nop(TCGContext *s, uint16_t *opc_ptr,
}
}
-/* liveness analysis: end of function: globals are live, temps are
- dead. */
-/* XXX: at this stage, not used as there would be little gains because
- most TBs end with a conditional jump. */
-static inline void tcg_la_func_end(TCGContext *s, uint8_t *dead_temps)
+/* liveness analysis: end of function: all temps are dead, and globals
+ should be in memory. */
+static inline void tcg_la_func_end(TCGContext *s, uint8_t *dead_temps,
+ uint8_t *mem_temps)
{
- memset(dead_temps, 0, s->nb_globals);
- memset(dead_temps + s->nb_globals, 1, s->nb_temps - s->nb_globals);
+ memset(dead_temps, 1, s->nb_temps);
+ memset(mem_temps, 1, s->nb_globals);
+ memset(mem_temps + s->nb_globals, 0, s->nb_temps - s->nb_globals);
}
-/* liveness analysis: end of basic block: globals are live, temps are
- dead, local temps are live. */
-static inline void tcg_la_bb_end(TCGContext *s, uint8_t *dead_temps)
+/* liveness analysis: end of basic block: all temps are dead, globals
+ and local temps should be in memory. */
+static inline void tcg_la_bb_end(TCGContext *s, uint8_t *dead_temps,
+ uint8_t *mem_temps)
{
int i;
- TCGTemp *ts;
- memset(dead_temps, 0, s->nb_globals);
- ts = &s->temps[s->nb_globals];
+ memset(dead_temps, 1, s->nb_temps);
+ memset(mem_temps, 1, s->nb_globals);
for(i = s->nb_globals; i < s->nb_temps; i++) {
- if (ts->temp_local)
- dead_temps[i] = 0;
- else
- dead_temps[i] = 1;
- ts++;
+ mem_temps[i] = s->temps[i].temp_local;
}
}
@@ -1217,7 +1213,7 @@ static void tcg_liveness_analysis(TCGContext *s)
TCGOpcode op;
TCGArg *args;
const TCGOpDef *def;
- uint8_t *dead_temps;
+ uint8_t *dead_temps, *mem_temps;
uint16_t dead_args;
uint8_t sync_args;
@@ -1229,7 +1225,8 @@ static void tcg_liveness_analysis(TCGContext *s)
s->op_sync_args = tcg_malloc(nb_ops * sizeof(uint8_t));
dead_temps = tcg_malloc(s->nb_temps);
- memset(dead_temps, 1, s->nb_temps);
+ mem_temps = tcg_malloc(s->nb_temps);
+ tcg_la_func_end(s, dead_temps, mem_temps);
args = gen_opparam_ptr;
op_index = nb_ops - 1;
@@ -1253,8 +1250,9 @@ static void tcg_liveness_analysis(TCGContext *s)
if (call_flags & TCG_CALL_PURE) {
for(i = 0; i < nb_oargs; i++) {
arg = args[i];
- if (!dead_temps[arg])
+ if (!dead_temps[arg] || mem_temps[arg]) {
goto do_not_remove_call;
+ }
}
tcg_set_nop(s, gen_opc_buf + op_index,
args - 1, nb_args);
@@ -1269,12 +1267,17 @@ static void tcg_liveness_analysis(TCGContext *s)
if (dead_temps[arg]) {
dead_args |= (1 << i);
}
+ if (mem_temps[arg]) {
+ sync_args |= (1 << i);
+ }
dead_temps[arg] = 1;
+ mem_temps[arg] = 0;
}
if (!(call_flags & TCG_CALL_CONST)) {
- /* globals are live (they may be used by the call) */
- memset(dead_temps, 0, s->nb_globals);
+ /* globals should go back to memory */
+ memset(dead_temps, 1, s->nb_globals);
+ memset(mem_temps, 1, s->nb_globals);
}
/* input args are live */
@@ -1304,6 +1307,7 @@ static void tcg_liveness_analysis(TCGContext *s)
args--;
/* mark the temporary as dead */
dead_temps[args[0]] = 1;
+ mem_temps[args[0]] = 0;
break;
case INDEX_op_end:
break;
@@ -1369,8 +1373,9 @@ static void tcg_liveness_analysis(TCGContext *s)
if (!(def->flags & TCG_OPF_SIDE_EFFECTS) && nb_oargs != 0) {
for(i = 0; i < nb_oargs; i++) {
arg = args[i];
- if (!dead_temps[arg])
+ if (!dead_temps[arg] || mem_temps[arg]) {
goto do_not_remove;
+ }
}
do_remove:
tcg_set_nop(s, gen_opc_buf + op_index, args, def->nb_args);
@@ -1388,15 +1393,20 @@ static void tcg_liveness_analysis(TCGContext *s)
if (dead_temps[arg]) {
dead_args |= (1 << i);
}
+ if (mem_temps[arg]) {
+ sync_args |= (1 << i);
+ }
dead_temps[arg] = 1;
+ mem_temps[arg] = 0;
}
/* if end of basic block, update */
if (def->flags & TCG_OPF_BB_END) {
- tcg_la_bb_end(s, dead_temps);
+ tcg_la_bb_end(s, dead_temps, mem_temps);
} else if (def->flags & TCG_OPF_CALL_CLOBBER) {
- /* globals are live */
- memset(dead_temps, 0, s->nb_globals);
+ /* globals should go back to memory */
+ memset(dead_temps, 1, s->nb_globals);
+ memset(mem_temps, 1, s->nb_globals);
}
/* input args are live */