clang/unittests/Serialization/VarDeclConstantInitTest.cpp

   1 //===- unittests/Serialization/VarDeclConstantInitTest.cpp - CI tests -----===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "clang/ASTMatchers/ASTMatchFinder.h"
  10 #include "clang/ASTMatchers/ASTMatchers.h"
  11 #include "clang/Basic/FileManager.h"
  12 #include "clang/Frontend/CompilerInstance.h"
  13 #include "clang/Frontend/CompilerInvocation.h"
  14 #include "clang/Frontend/FrontendActions.h"
  15 #include "clang/Frontend/Utils.h"
  16 #include "clang/Lex/HeaderSearch.h"
  17 #include "clang/Tooling/Tooling.h"
  18 #include "llvm/ADT/SmallString.h"
  19 #include "llvm/Support/FileSystem.h"
  20 #include "llvm/Support/raw_ostream.h"
  21
  22 #include "gtest/gtest.h"
  23
  24 using namespace llvm;
  25 using namespace clang;
  26
  27 namespace {
  28
  29 class VarDeclConstantInitTest : public ::testing::Test {
  30   void SetUp() override {
  31     ASSERT_FALSE(sys::fs::createUniqueDirectory("modules-test", TestDir));
  32   }
  33
  34   void TearDown() override { sys::fs::remove_directories(TestDir); }
  35
  36 public:
  37   SmallString<256> TestDir;
  38
  39   void addFile(StringRef Path, StringRef Contents) {
  40     ASSERT_FALSE(sys::path::is_absolute(Path));
  41
  42     SmallString<256> AbsPath(TestDir);
  43     sys::path::append(AbsPath, Path);
  44
  45     ASSERT_FALSE(
  46         sys::fs::create_directories(llvm::sys::path::parent_path(AbsPath)));
  47
  48     std::error_code EC;
  49     llvm::raw_fd_ostream OS(AbsPath, EC);
  50     ASSERT_FALSE(EC);
  51     OS << Contents;
  52   }
  53 };
  54
  55 TEST_F(VarDeclConstantInitTest, CachedConstantInit) {
  56   addFile("Cached.cppm", R"cpp(
  57 export module Fibonacci.Cache;
  58
  59 export namespace Fibonacci
  60 {
  61         constexpr unsigned long Recursive(unsigned long n)
  62         {
  63                 if (n == 0)
  64                         return 0;
  65                 if (n == 1)
  66                         return 1;
  67                 return Recursive(n - 2) + Recursive(n - 1);
  68         }
  69
  70         template<unsigned long N>
  71         struct Number{};
  72
  73         struct DefaultStrategy
  74         {
  75                 constexpr unsigned long operator()(unsigned long n, auto... other) const
  76                 {
  77                         return (n + ... + other);
  78                 }
  79         };
  80
  81   constexpr unsigned long Compute(Number<10ul>, auto strategy)
  82         {
  83                 return strategy(Recursive(10ul));
  84         }
  85
  86         template<unsigned long N, typename Strategy = DefaultStrategy>
  87         constexpr unsigned long Cache = Compute(Number<N>{}, Strategy{});
  88
  89   template constexpr unsigned long Cache<10ul>;
  90 }
  91   )cpp");
  92
  93   IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
  94       CompilerInstance::createDiagnostics(new DiagnosticOptions());
  95   CreateInvocationOptions CIOpts;
  96   CIOpts.Diags = Diags;
  97   CIOpts.VFS = llvm::vfs::createPhysicalFileSystem();
  98
  99   std::string CacheBMIPath = llvm::Twine(TestDir + "/Cached.pcm").str();
 100   const char *Args[] = {
 101       "clang++",       "-std=c++20",  "--precompile", "-working-directory",
 102       TestDir.c_str(), "Cached.cppm", "-o",           CacheBMIPath.c_str()};
 103   std::shared_ptr<CompilerInvocation> Invocation =
 104       createInvocation(Args, CIOpts);
 105   ASSERT_TRUE(Invocation);
 106
 107   CompilerInstance Instance;
 108   Instance.setDiagnostics(Diags.get());
 109   Instance.setInvocation(Invocation);
 110   GenerateModuleInterfaceAction Action;
 111   ASSERT_TRUE(Instance.ExecuteAction(Action));
 112   ASSERT_FALSE(Diags->hasErrorOccurred());
 113
 114   std::string DepArg =
 115       llvm::Twine("-fmodule-file=Fibonacci.Cache=" + CacheBMIPath).str();
 116   std::unique_ptr<ASTUnit> AST = tooling::buildASTFromCodeWithArgs(
 117       R"cpp(
 118 import Fibonacci.Cache;
 119         )cpp",
 120       /*Args=*/{"-std=c++20", DepArg.c_str()});
 121
 122   using namespace clang::ast_matchers;
 123   ASTContext &Ctx = AST->getASTContext();
 124   const auto *cached = selectFirst<VarDecl>(
 125       "Cache",
 126       match(varDecl(isTemplateInstantiation(), hasName("Cache")).bind("Cache"),
 127             Ctx));
 128   EXPECT_TRUE(cached);
 129   EXPECT_TRUE(cached->getEvaluatedStmt());
 130   EXPECT_TRUE(cached->getEvaluatedStmt()->WasEvaluated);
 131   EXPECT_TRUE(cached->getEvaluatedValue());
 132   EXPECT_TRUE(cached->getEvaluatedValue()->isInt());
 133   EXPECT_EQ(cached->getEvaluatedValue()->getInt(), 55);
 134 }
 135
 136 } // anonymous namespace