diff --git a/src/jit/backend/x64/x64_backend.cc b/src/jit/backend/x64/x64_backend.cc
index 1223c656..9fe1e574 100644
--- a/src/jit/backend/x64/x64_backend.cc
+++ b/src/jit/backend/x64/x64_backend.cc
@@ -1609,6 +1609,8 @@ EMITTER(CALL_FALLBACK) {
   e.call(fallback);
 }
 
+EMITTER(DEBUG_INFO) {}
+
 void x64_backend_destroy(struct jit_backend *jit_backend) {
   struct x64_backend *backend = (struct x64_backend *)jit_backend;
 
diff --git a/src/jit/frontend/sh4/sh4_translate.c b/src/jit/frontend/sh4/sh4_translate.c
index f07bccf0..a1c19e16 100644
--- a/src/jit/frontend/sh4/sh4_translate.c
+++ b/src/jit/frontend/sh4/sh4_translate.c
@@ -218,6 +218,9 @@ static void ir_branch_true_guest(struct sh4_frontend *frontend, struct ir *ir,
 void sh4_emit_instr(struct sh4_frontend *frontend, struct ir *ir, int flags,
                     const struct sh4_instr *instr,
                     const struct sh4_instr *delay) {
+  /* emit debug info op for recc metrics */
+  ir_debug_info(ir, instr->addr, ir_alloc_i16(ir, instr->opcode));
+
   (emit_callbacks[instr->op])(frontend, ir, flags, instr, delay);
 }
 
diff --git a/src/jit/ir/ir.c b/src/jit/ir/ir.c
index cce50e2a..016e8945 100644
--- a/src/jit/ir/ir.c
+++ b/src/jit/ir/ir.c
@@ -21,7 +21,7 @@ static struct ir_instr *ir_alloc_instr(struct ir *ir, enum ir_op op) {
 
   instr->op = op;
 
-  // initialize use links
+  /* initialize use links */
   for (int i = 0; i < MAX_INSTR_ARGS; i++) {
     struct ir_use *use = &instr->used[i];
     use->instr = instr;
@@ -43,7 +43,7 @@ struct ir_instr *ir_append_instr(struct ir *ir, enum ir_op op,
                                  enum ir_type result_type) {
   struct ir_instr *instr = ir_alloc_instr(ir, op);
 
-  // allocate result if needed
+  /* allocate result if needed */
   if (result_type != VALUE_V) {
     struct ir_value *result = ir_calloc(ir, sizeof(struct ir_value));
     result->type = result_type;
@@ -60,7 +60,7 @@ struct ir_instr *ir_append_instr(struct ir *ir, enum ir_op op,
 }
 
 void ir_remove_instr(struct ir *ir, struct ir_instr *instr) {
-  // remove arguments from the use lists of their values
+  /* remove arguments from the use lists of their values */
   for (int i = 0; i < MAX_INSTR_ARGS; i++) {
     struct ir_value *value = instr->arg[i];
 
@@ -167,7 +167,7 @@ struct ir_value *ir_alloc_label(struct ir *ir, const char *format, ...) {
 }
 
 struct ir_local *ir_alloc_local(struct ir *ir, enum ir_type type) {
-  // align local to natural size
+  /* align local to natural size */
   int type_size = ir_type_size(type);
   ir->locals_size = align_up(ir->locals_size, type_size);
 
@@ -218,8 +218,8 @@ void ir_replace_use(struct ir_use *use, struct ir_value *other) {
   }
 }
 
-// replace all uses of v with other
 void ir_replace_uses(struct ir_value *v, struct ir_value *other) {
+  /* replace all uses of v with other */
   CHECK_NE(v, other);
 
   list_for_each_entry_safe(use, &v->uses, struct ir_use, it) {
@@ -825,3 +825,9 @@ void ir_call_fallback(struct ir *ir, void *fallback, uint32_t addr,
   ir_set_arg1(ir, instr, ir_alloc_i32(ir, addr));
   ir_set_arg2(ir, instr, ir_alloc_i32(ir, raw_instr));
 }
+
+void ir_debug_info(struct ir *ir, uint32_t addr, struct ir_value *data) {
+  struct ir_instr *instr = ir_append_instr(ir, OP_DEBUG_INFO, VALUE_V);
+  ir_set_arg0(ir, instr, ir_alloc_i32(ir, addr));
+  ir_set_arg1(ir, instr, data);
+}
diff --git a/src/jit/ir/ir.h b/src/jit/ir/ir.h
index 9bf9aab2..3855c270 100644
--- a/src/jit/ir/ir.h
+++ b/src/jit/ir/ir.h
@@ -41,16 +41,16 @@ enum ir_cmp {
 struct ir_value;
 struct ir_instr;
 
-// use is a layer of indirection between an instruction and the values it uses
-// as arguments. this indirection makes it possible to maintain a list for each
-// value of the arguments that reference it
+/* use is a layer of indirection between an instruction and the values it uses
+   as arguments. this indirection makes it possible to maintain a list for each
+   value of the arguments that reference it */
 struct ir_use {
-  // the instruction that's using the value
+  /* the instruction that's using the value */
   struct ir_instr *instr;
 
-  // pointer to the argument that's using the value. this is used to substitute
-  // a new value for the argument in the case that the original value is
-  // removed (e.g. due to constant propagation)
+  /* pointer to the argument that's using the value. this is used to substitute
+     a new value for the argument in the case that the original value is
+     removed (e.g. due to constant propagation) */
   struct ir_value **parg;
 
   struct list_node it;
@@ -69,16 +69,16 @@ struct ir_value {
     char *str;
   };
 
-  // instruction that defines this value (non-constant values)
+  /* instruction that defines this value (non-constant values) */
   struct ir_instr *def;
 
-  // instructions that use this value as an argument
+  /* instructions that use this value as an argument */
   struct list uses;
 
-  // host register allocated for this value
+  /* host register allocated for this value */
   int reg;
 
-  // generic meta data used by optimization passes
+  /* generic meta data used by optimization passes */
   intptr_t tag;
 };
 
@@ -87,24 +87,24 @@ struct ir_value {
 struct ir_instr {
   enum ir_op op;
 
-  // values used by each argument. note, the argument / use is split into two
-  // separate members to ease reading the argument value (instr->arg[0] vs
-  // instr->arg[0].value)
+  /* values used by each argument. note, the argument / use is split into two
+     separate members to ease reading the argument value (instr->arg[0] vs
+     instr->arg[0].value) */
   struct ir_value *arg[MAX_INSTR_ARGS];
   struct ir_use used[MAX_INSTR_ARGS];
 
-  // result of the instruction. note, instruction results don't consider
-  // themselves users of the value (eases register allocation logic)
+  /* result of the instruction. note, instruction results don't consider
+     themselves users of the value (eases register allocation logic) */
   struct ir_value *result;
 
-  // generic meta data used by optimization passes
+  /* generic meta data used by optimization passes */
   intptr_t tag;
 
   struct list_node it;
 };
 
-// locals are allocated for values that need to be spilled to the stack
-// during register allocation
+/* locals are allocated for values that need to be spilled to the stack
+   during register allocation */
 struct ir_local {
   enum ir_type type;
   struct ir_value *offset;
@@ -208,12 +208,12 @@ void ir_replace_uses(struct ir_value *v, struct ir_value *other);
 
 uint64_t ir_zext_constant(const struct ir_value *v);
 
-// direct access to host memory
+/* direct access to host memory */
 struct ir_value *ir_load(struct ir *ir, struct ir_value *addr,
                          enum ir_type type);
 void ir_store(struct ir *ir, struct ir_value *addr, struct ir_value *v);
 
-// guest memory operations
+/* guest memory operations */
 struct ir_value *ir_load_fast(struct ir *ir, struct ir_value *addr,
                               enum ir_type type);
 void ir_store_fast(struct ir *ir, struct ir_value *addr, struct ir_value *v);
@@ -222,16 +222,16 @@ struct ir_value *ir_load_slow(struct ir *ir, struct ir_value *addr,
                               enum ir_type type);
 void ir_store_slow(struct ir *ir, struct ir_value *addr, struct ir_value *v);
 
-// context operations
+/* context operations */
 struct ir_value *ir_load_context(struct ir *ir, size_t offset,
                                  enum ir_type type);
 void ir_store_context(struct ir *ir, size_t offset, struct ir_value *v);
 
-// local operations
+/* local operations */
 struct ir_value *ir_load_local(struct ir *ir, struct ir_local *local);
 void ir_store_local(struct ir *ir, struct ir_local *local, struct ir_value *v);
 
-// cast / conversion operations
+/* cast / conversion operations */
 struct ir_value *ir_ftoi(struct ir *ir, struct ir_value *v,
                          enum ir_type dest_type);
 struct ir_value *ir_itof(struct ir *ir, struct ir_value *v,
@@ -247,7 +247,7 @@ struct ir_value *ir_fext(struct ir *ir, struct ir_value *v,
 struct ir_value *ir_ftrunc(struct ir *ir, struct ir_value *v,
                            enum ir_type dest_type);
 
-// conditionals
+/* conditionals */
 struct ir_value *ir_select(struct ir *ir, struct ir_value *cond,
                            struct ir_value *t, struct ir_value *f);
 struct ir_value *ir_cmp_eq(struct ir *ir, struct ir_value *a,
@@ -283,7 +283,7 @@ struct ir_value *ir_fcmp_le(struct ir *ir, struct ir_value *a,
 struct ir_value *ir_fcmp_lt(struct ir *ir, struct ir_value *a,
                             struct ir_value *b);
 
-// integer math operators
+/* integer math operators */
 struct ir_value *ir_add(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_sub(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_smul(struct ir *ir, struct ir_value *a, struct ir_value *b);
@@ -292,7 +292,7 @@ struct ir_value *ir_div(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_neg(struct ir *ir, struct ir_value *a);
 struct ir_value *ir_abs(struct ir *ir, struct ir_value *a);
 
-// floating point math operators
+/* floating point math operators */
 struct ir_value *ir_fadd(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_fsub(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_fmul(struct ir *ir, struct ir_value *a, struct ir_value *b);
@@ -301,7 +301,7 @@ struct ir_value *ir_fneg(struct ir *ir, struct ir_value *a);
 struct ir_value *ir_fabs(struct ir *ir, struct ir_value *a);
 struct ir_value *ir_sqrt(struct ir *ir, struct ir_value *a);
 
-// vector math operators
+/* vector math operators */
 struct ir_value *ir_vbroadcast(struct ir *ir, struct ir_value *a);
 struct ir_value *ir_vadd(struct ir *ir, struct ir_value *a, struct ir_value *b,
                          enum ir_type el_type);
@@ -310,7 +310,7 @@ struct ir_value *ir_vdot(struct ir *ir, struct ir_value *a, struct ir_value *b,
 struct ir_value *ir_vmul(struct ir *ir, struct ir_value *a, struct ir_value *b,
                          enum ir_type el_type);
 
-// bitwise operations
+/* bitwise operations */
 struct ir_value *ir_and(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_or(struct ir *ir, struct ir_value *a, struct ir_value *b);
 struct ir_value *ir_xor(struct ir *ir, struct ir_value *a, struct ir_value *b);
@@ -324,14 +324,14 @@ struct ir_value *ir_lshri(struct ir *ir, struct ir_value *a, int n);
 struct ir_value *ir_ashd(struct ir *ir, struct ir_value *a, struct ir_value *n);
 struct ir_value *ir_lshd(struct ir *ir, struct ir_value *a, struct ir_value *n);
 
-// branches
+/* branches */
 void ir_label(struct ir *ir, struct ir_value *lbl);
 void ir_branch(struct ir *ir, struct ir_value *dst);
 void ir_branch_false(struct ir *ir, struct ir_value *cond,
                      struct ir_value *dst);
 void ir_branch_true(struct ir *ir, struct ir_value *cond, struct ir_value *dst);
 
-// calls
+/* calls */
 void ir_call(struct ir *ir, struct ir_value *fn);
 void ir_call_1(struct ir *ir, struct ir_value *fn, struct ir_value *arg0);
 void ir_call_2(struct ir *ir, struct ir_value *fn, struct ir_value *arg0,
@@ -339,4 +339,7 @@ void ir_call_2(struct ir *ir, struct ir_value *fn, struct ir_value *arg0,
 void ir_call_fallback(struct ir *ir, void *fallback, uint32_t addr,
                       uint32_t raw_instr);
 
+/* debug */
+void ir_debug_info(struct ir *ir, uint32_t addr, struct ir_value *data);
+
 #endif
diff --git a/src/jit/ir/ir_ops.inc b/src/jit/ir/ir_ops.inc
index 04b83013..4e1cf524 100644
--- a/src/jit/ir/ir_ops.inc
+++ b/src/jit/ir/ir_ops.inc
@@ -51,3 +51,4 @@ IR_OP(BRANCH_FALSE)
 IR_OP(BRANCH_TRUE)
 IR_OP(CALL)
 IR_OP(CALL_FALLBACK)
+IR_OP(DEBUG_INFO)
diff --git a/tools/recc/recc.c b/tools/recc/recc.c
index e5541230..465e3cd0 100644
--- a/tools/recc/recc.c
+++ b/tools/recc/recc.c
@@ -18,6 +18,7 @@ DEFINE_OPTION_STRING(pass, "lse,cve,esimp,dce,ra",
 DEFINE_OPTION_INT(stats, 1, "Print pass stats");
 DEFINE_OPTION_INT(print_after_all, 1, "Print IR after each pass");
 
+DEFINE_STAT(frontend_size, "Frontend code size");
 DEFINE_STAT(backend_size, "Backend code size");
 DEFINE_STAT(num_instrs, "Total instructions");
 DEFINE_STAT(num_instrs_removed, "Total instructions removed");
@@ -51,12 +52,20 @@ static void process_file(struct jit *jit, const char *filename,
   fclose(input);
   CHECK(r);
 
-  int num_instrs_before = get_num_instrs(&ir);
+  /* calculate frontend input size */
+  list_for_each_entry(instr, &ir.instrs, struct ir_instr, it) {
+    if (instr->op == OP_DEBUG_INFO) {
+      struct ir_value *data = instr->arg[1];
+      STAT_frontend_size += ir_type_size(data->type);
+    }
+  }
 
   /* run optimization passes */
   char passes[MAX_OPTION_LENGTH];
   strncpy(passes, OPTION_pass, sizeof(passes));
 
+  int num_instrs_before = get_num_instrs(&ir);
+
   char *name = strtok(passes, ",");
   while (name) {
     if (!strcmp(name, "lse")) {
@@ -85,12 +94,13 @@ static void process_file(struct jit *jit, const char *filename,
     name = strtok(NULL, ",");
   }
 
+  int num_instrs_after = get_num_instrs(&ir);
+
   /* print out the final ir */
   if (!disable_ir_dump && !OPTION_print_after_all) {
     ir_write(&ir, stdout);
   }
 
-  int num_instrs_after = get_num_instrs(&ir);
   STAT_num_instrs += num_instrs_before;
   STAT_num_instrs_removed += num_instrs_before - num_instrs_after;