From 87b2d1d04ed6d2e46e961a9f73bb8d607d8692da Mon Sep 17 00:00:00 2001
From: Valentin Clement <clementval@gmail.com>
Date: Tue, 18 Oct 2022 19:52:20 +0200
Subject: [PATCH] [flang] Add getTypeDescriptorBindingTableName function

Type descriptor and its binding table are defined as fir.global in FIR.
Their names are derived from the derived-type name. This patch adds a new
function `getTypeDescriptorBindingTableName` in the NameUniquer and
refactor the `GetTypeDescriptorName` function to reuse the same code.
This will be used in the fir.dispatch code generation.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D136167
---
 .../flang/Optimizer/Support/InternalNames.h        |  9 +++++++++
 flang/lib/Optimizer/Support/InternalNames.cpp      | 22 ++++++++++++++++------
 flang/unittests/Optimizer/InternalNamesTest.cpp    | 17 +++++++++++++++++
 3 files changed, 42 insertions(+), 6 deletions(-)

diff --git a/flang/include/flang/Optimizer/Support/InternalNames.h b/flang/include/flang/Optimizer/Support/InternalNames.h
index ab6a477..6defb3d 100644
--- a/flang/include/flang/Optimizer/Support/InternalNames.h
+++ b/flang/include/flang/Optimizer/Support/InternalNames.h
@@ -14,6 +14,9 @@
 #include "llvm/ADT/StringRef.h"
 #include <cstdint>
 
+static constexpr llvm::StringRef typeDescriptorSeparator = ".dt.";
+static constexpr llvm::StringRef bindingTableSeparator = ".v.";
+
 namespace fir {
 
 /// Internal name mangling of identifiers
@@ -142,6 +145,12 @@ struct NameUniquer {
   /// not a valid mangled derived type name.
   static std::string getTypeDescriptorName(llvm::StringRef mangledTypeName);
 
+  /// Given a mangled derived type name, get the name of the related binding
+  /// table object. Returns an empty string if \p mangledTypeName is not a valid
+  /// mangled derived type name.
+  static std::string
+  getTypeDescriptorBindingTableName(llvm::StringRef mangledTypeName);
+
 private:
   static std::string intAsString(std::int64_t i);
   static std::string doKind(std::int64_t kind);
diff --git a/flang/lib/Optimizer/Support/InternalNames.cpp b/flang/lib/Optimizer/Support/InternalNames.cpp
index b1cedb0..d908660 100644
--- a/flang/lib/Optimizer/Support/InternalNames.cpp
+++ b/flang/lib/Optimizer/Support/InternalNames.cpp
@@ -335,12 +335,12 @@ mangleTypeDescriptorKinds(llvm::ArrayRef<std::int64_t> kinds) {
   return result;
 }
 
-std::string
-fir::NameUniquer::getTypeDescriptorName(llvm::StringRef mangledTypeName) {
-  auto result = deconstruct(mangledTypeName);
-  if (result.first != NameKind::DERIVED_TYPE)
+static std::string getDerivedTypeObjectName(llvm::StringRef mangledTypeName,
+                                            const llvm::StringRef separator) {
+  auto result = fir::NameUniquer::deconstruct(mangledTypeName);
+  if (result.first != fir::NameUniquer::NameKind::DERIVED_TYPE)
     return "";
-  std::string varName = ".dt." + result.second.name +
+  std::string varName = separator.str() + result.second.name +
                         mangleTypeDescriptorKinds(result.second.kinds);
   llvm::SmallVector<llvm::StringRef> modules;
   for (const std::string &mod : result.second.modules)
@@ -348,5 +348,15 @@ fir::NameUniquer::getTypeDescriptorName(llvm::StringRef mangledTypeName) {
   llvm::Optional<llvm::StringRef> host;
   if (result.second.host)
     host = *result.second.host;
-  return doVariable(modules, host, varName);
+  return fir::NameUniquer::doVariable(modules, host, varName);
+}
+
+std::string
+fir::NameUniquer::getTypeDescriptorName(llvm::StringRef mangledTypeName) {
+  return getDerivedTypeObjectName(mangledTypeName, typeDescriptorSeparator);
+}
+
+std::string fir::NameUniquer::getTypeDescriptorBindingTableName(
+    llvm::StringRef mangledTypeName) {
+  return getDerivedTypeObjectName(mangledTypeName, bindingTableSeparator);
 }
diff --git a/flang/unittests/Optimizer/InternalNamesTest.cpp b/flang/unittests/Optimizer/InternalNamesTest.cpp
index 3453c5e..fca8ac1 100644
--- a/flang/unittests/Optimizer/InternalNamesTest.cpp
+++ b/flang/unittests/Optimizer/InternalNamesTest.cpp
@@ -255,4 +255,21 @@ TEST(InternalNamesTest, isExternalFacingUniquedName) {
   ASSERT_TRUE(NameUniquer::isExternalFacingUniquedName(result));
 }
 
+TEST(InternalNamesTest, getTypeDescriptorName) {
+  std::string derivedTypeName = "_QMdispatch1Tp1";
+  std::string expectedBindingTableName = "_QMdispatch1E.dt.p1";
+  ASSERT_EQ(expectedBindingTableName,
+      fir::NameUniquer::getTypeDescriptorName(derivedTypeName));
+  ASSERT_EQ("", fir::NameUniquer::getTypeDescriptorName("_QMdispatch1Pp1"));
+}
+
+TEST(InternalNamesTest, getTypeDescriptorBindingTableName) {
+  std::string derivedTypeName = "_QMdispatch1Tp1";
+  std::string expectedBindingTableName = "_QMdispatch1E.v.p1";
+  ASSERT_EQ(expectedBindingTableName,
+      fir::NameUniquer::getTypeDescriptorBindingTableName(derivedTypeName));
+  ASSERT_EQ("",
+      fir::NameUniquer::getTypeDescriptorBindingTableName("_QMdispatch1Pp1"));
+}
+
 // main() from gtest_main
-- 
2.7.4