Draft

Some errors occur when using const_opt IR

Makefile

@@ -88,6 +88,27 @@ gdbstub-test: $(BIN)
 	$(Q).ci/gdbstub-test.sh && $(call notice, [OK])
 endif
 
+ENABLE_JIT ?= 0
+$(call set-feature, JIT)
+ifeq ($(call has, JIT), 1)
+CFLAGS += -I./src/mir
+LDFLAGS += src/mir/libmir.a -lpthread
+OBJS_EXT += compile.o
+
+src/jit_template.c:
+	$(Q)tools/gen-jit-template.py $(CFLAGS) > $@
+
+src/mir/GNUmakefile:
+	git submodule update --init $(dir $@)
+
+src/mir/libmir.a: src/mir/GNUmakefile
+	$(MAKE) --quiet -C src/mir
+
+$(OUT)/compile.o: src/compile.c src/mir/libmir.a src/jit_template.c
+	$(VECHO) "  CC\t$@\n"
+	$(Q)$(CC) -o $@ $(CFLAGS) -c -MMD -MF $@.d $<
+endif
+
 # For tail-call elimination, we need a specific set of build flags applied.
 # FIXME: On macOS + Apple Silicon, -fno-stack-protector might have a negative impact.
 $(OUT)/emulate.o: CFLAGS += $(CFLAGS_NO_CET) -fomit-frame-pointer -fno-stack-check -fno-stack-protector
@@ -182,7 +203,7 @@ endif
 endif
 
 clean:
-	$(RM) $(BIN) $(OBJS) $(HIST_BIN) $(HIST_OBJS) $(deps) $(CACHE_OUT)
+	$(RM) $(BIN) $(OBJS) $(HIST_BIN) $(HIST_OBJS) $(deps) $(CACHE_OUT) src/jit_template.c
 distclean: clean
 	-$(RM) $(DOOM_DATA) $(QUAKE_DATA)
 	$(RM) -r $(OUT)/id1

src/cache.c

@@ -11,16 +11,20 @@
 
 #include "cache.h"
 #include "mpool.h"
+#include "utils.h"
 
 #define MIN(a, b) ((a < b) ? a : b)
-#define GOLDEN_RATIO_32 0x61C88647
 #define HASH(val) \
     (((val) * (GOLDEN_RATIO_32)) >> (32 - (cache_size_bits))) & (cache_size - 1)
 
 /* THRESHOLD is set to identify hot spots. Once the frequency of use for a block
  * exceeds the THRESHOLD, the JIT compiler flow is triggered.
  */
-#define THRESHOLD 1000
+#define THRESHOLD 32768
+#if RV32_HAS(JIT)
+#define sys_icache_invalidate(addr, size) \
+    __builtin___clear_cache((char *) (addr), (char *) (addr) + (size));
+#endif
 
 static uint32_t cache_size, cache_size_bits;
 static struct mpool *cache_mp;
@@ -541,3 +545,37 @@ void cache_free(cache_t *cache, void (*callback)(void *))
     free(cache->map);
     free(cache);
 }
+
+#if RV32_HAS(JIT)
+bool cache_hot(struct cache *cache, uint32_t key)
+{
+    if (!cache->capacity || hlist_empty(&cache->map->ht_list_head[HASH(key)]))
+        return false;
+#if RV32_HAS(ARC)
+    arc_entry_t *entry = NULL;
+#ifdef __HAVE_TYPEOF
+    hlist_for_each_entry (entry, &cache->map->ht_list_head[HASH(key)], ht_list)
+#else
+    hlist_for_each_entry (entry, &cache->map->ht_list_head[HASH(key)], ht_list,
+                          arc_entry_t)
+#endif
+    {
+        if (entry->key == key && entry->frequency == THRESHOLD)
+            return true;
+    }
+#else
+    lfu_entry_t *entry = NULL;
+#ifdef __HAVE_TYPEOF
+    hlist_for_each_entry (entry, &cache->map->ht_list_head[HASH(key)], ht_list)
+#else
+    hlist_for_each_entry (entry, &cache->map->ht_list_head[HASH(key)], ht_list,
+                          lfu_entry_t)
+#endif
+    {
+        if (entry->key == key && entry->frequency == THRESHOLD)
+            return true;
+    }
+#endif
+    return false;
+}
+#endif

src/cache.h

@@ -5,6 +5,7 @@
 
 #pragma once
 
+#include <stdbool.h>
 #include <stdint.h>
 
 struct cache;
@@ -38,3 +39,13 @@ void *cache_put(struct cache *cache, uint32_t key, void *value);
  * @callback: a function for freeing cache entry completely
  */
 void cache_free(struct cache *cache, void (*callback)(void *));
+
+#if RV32_HAS(JIT)
+/**
+ * cache_hot - check whether the frequency of the cache entry exceeds the
+ * threshold or not
+ * @cache: a pointer points to target cache
+ * @key: the key of the specified entry
+ */
+bool cache_hot(struct cache *cache, uint32_t key);
+#endif