[FRONTEND] Fix libdevice (#776)

Fix two problems in libdevice and external dispatch:

1. Use static triton types (e.g., tl.int32) instead of creating new
types. Otherwise, `tl.int32` and `tl.dtype('int32')` are not the same
thing.

2. The name of an extern inst should be empty but not the symbol name of
the inst. TTIR generator will assign names automatically. Otherwise, we
have the same variable name when there are multiple same extern insts.

Before the PR:

```bash
  __nv_exp = extern_elementwise f64<1024> %11;
  __nv_exp = extern_elementwise f64<1024> %11;
```

After the PR:

```bash
  %12 = extern_elementwise f64<1024> %11;
  %13 = extern_elementwise f64<1024> %11;
```

include/triton/ir/instructions.h

@@ -1119,7 +1119,8 @@ class extern_elementwise_inst : public instruction {
   extern_elementwise_inst(context &ctx, const std::vector<value *> &args,
                           type *dst_ty, const std::string &lib_name,
                           const std::string &extern_lib_path,
-                          const std::string &symbol_name, instruction *next);
+                          const std::string &symbol_name,
+                          const std::string &name, instruction *next);
   std::string repr_impl() const { return "extern_elementwise"; }
   _TRITON_DEFINE_CLONE(extern_elementwise_inst)
   _TRITON_DEFINE_ACCEPT(extern_elementwise_inst)
@@ -1128,14 +1129,17 @@ class extern_elementwise_inst : public instruction {
   static extern_elementwise_inst *create(
       context &ctx, const std::vector<value *> &args, type *dst_ty,
       const std::string &lib_name = "", const std::string &lib_path = "",
-      const std::string &symbol_name = "", instruction *next = nullptr);
+      const std::string &symbol_name = "", const std::string &name = "",
+      instruction *next = nullptr);
 
   const std::string &get_lib_name() const { return lib_name_; }
   const std::string &get_lib_path() const { return lib_path_; }
+  const std::string &get_symbol_name() const { return symbol_name_; }
 
  private:
-  std::string lib_name_ = "";
+  std::string lib_name_;
-  std::string lib_path_ = "";
+  std::string lib_path_;
+  std::string symbol_name_;
 };
 }
 }

lib/codegen/selection/generator.cc

@@ -3531,7 +3531,7 @@ void generator::visit_extern_elementwise_inst(ir::extern_elementwise_inst *i) {
   FunctionType *FT =
       FunctionType::get(ret_type, std::move(operand_types), false);
   Function *F = llvm::cast<llvm::Function>(
-      mod_->getOrInsertFunction(i->get_name(), FT).getCallee());
+      mod_->getOrInsertFunction(i->get_symbol_name(), FT).getCallee());
   for (auto idx : idxs_.at(i)) {
     std::vector<llvm::Value *> args;
     for (size_t j = 0; j < i->get_num_operands(); j++) {

lib/ir/instructions.cc

@@ -1007,11 +1007,11 @@ globaltimer_inst* globaltimer_inst::create(context &ctx, const std::string &name
 extern_elementwise_inst::extern_elementwise_inst(
     context &ctx, const std::vector<value *> &args, type *ret_ty,
     const std::string &lib_name, const std::string &lib_path,
-    const std::string &symbol_name, instruction *next)
+    const std::string &symbol_name, const std::string &name, instruction *next)
-    : instruction(ret_ty, INST_EXTERN_ELEMENTWISE, args.size(), symbol_name,
+    : instruction(ret_ty, INST_EXTERN_ELEMENTWISE, args.size(), name, next),
-                  next),
       lib_name_(lib_name),
-      lib_path_(lib_path) {
+      lib_path_(lib_path),
+      symbol_name_(symbol_name) {
   for (size_t i = 0; i < args.size(); i++) {
     set_operand(i, args[i]);
   }
@@ -1020,9 +1020,10 @@ extern_elementwise_inst::extern_elementwise_inst(
 extern_elementwise_inst *extern_elementwise_inst::create(
     context &ctx, const std::vector<value *> &args, type *ret_ty,
     const std::string &lib_name, const std::string &lib_path,
-    const std::string &symbol_name, instruction *next) {
+    const std::string &symbol_name, const std::string &name,
+    instruction *next) {
   return new extern_elementwise_inst(ctx, args, ret_ty, lib_name, lib_path,
-                                     symbol_name, next);
+                                     symbol_name, name, next);
 }
 
 // clock

python/triton/tools/build_extern.py

@@ -51,9 +51,9 @@ def convert_type(type_str):
     elif type_str == "u64":
         return "uint64"
     elif type_str == "float":
-        return "fp32"
+        return "float32"
     elif type_str == "double":
-        return "fp64"
+        return "float64"
     else:
         # ignore other types, such as pointer types
         return None
@@ -268,8 +268,8 @@ class Libdevice(ExternLibrary):
             for symbol in symbols:
                 arg_type_symbol_dict_str += "("
                 for arg_type in symbol.arg_types:
-                    arg_type_symbol_dict_str += f"core.dtype(\"{arg_type}\"),"
+                    arg_type_symbol_dict_str += f"core.{arg_type},"
-                ret_type = f"core.dtype(\"{symbol.ret_type}\")"
+                ret_type = f"core.{symbol.ret_type}"
                 arg_type_symbol_dict_str += "): (\"" + symbol.name + "\", " + ret_type + "),\n"
             arg_type_symbol_dict_str += "}"