llvm · cachemeifyoucan · Jul 31, 2025 · Jul 22, 2025 · Jul 22, 2025 · Jul 30, 2025
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -643,16 +643,7 @@ unsigned CGDebugInfo::getColumnNumber(SourceLocation Loc, bool Force) {
 }
 
 StringRef CGDebugInfo::getCurrentDirname() {
-  if (!CGM.getCodeGenOpts().DebugCompilationDir.empty())
-    return CGM.getCodeGenOpts().DebugCompilationDir;
-
-  if (!CWDName.empty())
-    return CWDName;
-  llvm::ErrorOr<std::string> CWD =
-      CGM.getFileSystem()->getCurrentWorkingDirectory();
-  if (!CWD)
-    return StringRef();
-  return CWDName = internString(*CWD);
+  return CGM.getCodeGenOpts().DebugCompilationDir;
 }
 
 void CGDebugInfo::CreateCompileUnit() {
@@ -3246,6 +3237,9 @@ llvm::DIModule *CGDebugInfo::getOrCreateModuleRef(ASTSourceDescriptor Mod,
     std::string Remapped = remapDIPath(Path);
     StringRef Relative(Remapped);
     StringRef CompDir = TheCU->getDirectory();
+    if (CompDir.empty())
+      return Remapped;
+
     if (Relative.consume_front(CompDir))
       Relative.consume_front(llvm::sys::path::get_separator());
 

diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
@@ -158,7 +158,6 @@ class CGDebugInfo {
   /// This is a storage for names that are constructed on demand. For
   /// example, C++ destructors, C++ operators etc..
   llvm::BumpPtrAllocator DebugInfoNames;
-  StringRef CWDName;
 
   llvm::DenseMap<const char *, llvm::TrackingMDRef> DIFileCache;
   llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> SPCache;

diff --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp
@@ -2449,12 +2449,7 @@ CoverageMappingModuleGen::CoverageMappingModuleGen(
     : CGM(CGM), SourceInfo(SourceInfo) {}
 
 std::string CoverageMappingModuleGen::getCurrentDirname() {
-  if (!CGM.getCodeGenOpts().CoverageCompilationDir.empty())
-    return CGM.getCodeGenOpts().CoverageCompilationDir;
-
-  SmallString<256> CWD;
-  llvm::sys::fs::current_path(CWD);
-  return CWD.str().str();
+  return CGM.getCodeGenOpts().CoverageCompilationDir;
 }
 
 std::string CoverageMappingModuleGen::normalizeFilename(StringRef Filename) {

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -242,17 +242,18 @@ static bool ShouldEnableAutolink(const ArgList &Args, const ToolChain &TC,
 static const char *addDebugCompDirArg(const ArgList &Args,
                                       ArgStringList &CmdArgs,
                                       const llvm::vfs::FileSystem &VFS) {
+  std::string DebugCompDir;
   if (Arg *A = Args.getLastArg(options::OPT_ffile_compilation_dir_EQ,
-                               options::OPT_fdebug_compilation_dir_EQ)) {
-    if (A->getOption().matches(options::OPT_ffile_compilation_dir_EQ))
-      CmdArgs.push_back(Args.MakeArgString(Twine("-fdebug-compilation-dir=") +
-                                           A->getValue()));
+                               options::OPT_fdebug_compilation_dir_EQ))
+    DebugCompDir = A->getValue();
+
+  if (DebugCompDir.empty()) {
+    if (llvm::ErrorOr<std::string> CWD = VFS.getCurrentWorkingDirectory())
+      DebugCompDir = std::move(*CWD);
     else
-      A->render(Args, CmdArgs);
-  } else if (llvm::ErrorOr<std::string> CWD =
-                 VFS.getCurrentWorkingDirectory()) {
-    CmdArgs.push_back(Args.MakeArgString("-fdebug-compilation-dir=" + *CWD));
+      return nullptr;
   }
+  CmdArgs.push_back(Args.MakeArgString("-fdebug-compilation-dir=" + DebugCompDir));
   StringRef Path(CmdArgs.back());
   return Path.substr(Path.find('=') + 1).data();
 }
@@ -541,17 +542,17 @@ static void addPGOAndCoverageFlags(const ToolChain &TC, Compilation &C,
     CmdArgs.push_back("-fcoverage-mcdc");
   }
 
+  StringRef CoverageCompDir;
   if (Arg *A = Args.getLastArg(options::OPT_ffile_compilation_dir_EQ,
-                               options::OPT_fcoverage_compilation_dir_EQ)) {
-    if (A->getOption().matches(options::OPT_ffile_compilation_dir_EQ))
-      CmdArgs.push_back(Args.MakeArgString(
-          Twine("-fcoverage-compilation-dir=") + A->getValue()));
-    else
-      A->render(Args, CmdArgs);
-  } else if (llvm::ErrorOr<std::string> CWD =
-                 D.getVFS().getCurrentWorkingDirectory()) {
-    CmdArgs.push_back(Args.MakeArgString("-fcoverage-compilation-dir=" + *CWD));
-  }
+                               options::OPT_fcoverage_compilation_dir_EQ))
+    CoverageCompDir = A->getValue();
+  if (CoverageCompDir.empty()) {
+    if (auto CWD = D.getVFS().getCurrentWorkingDirectory())
+      CmdArgs.push_back(
+          Args.MakeArgString(Twine("-fcoverage-compilation-dir=") + *CWD));
+  } else
+    CmdArgs.push_back(Args.MakeArgString(Twine("-fcoverage-compilation-dir=") +
+                                         CoverageCompDir));
 
   if (Args.hasArg(options::OPT_fprofile_exclude_files_EQ)) {
     auto *Arg = Args.getLastArg(options::OPT_fprofile_exclude_files_EQ);

diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -144,30 +144,8 @@ static void optimizeDiagnosticOpts(DiagnosticOptions &Opts,
 
 static void optimizeCWD(CowCompilerInvocation &BuildInvocation, StringRef CWD) {
   BuildInvocation.getMutFileSystemOpts().WorkingDir.clear();
-  if (BuildInvocation.getCodeGenOpts().DwarfVersion) {
-    // It is necessary to explicitly set the DebugCompilationDir
-    // to a common directory (e.g. root) if IgnoreCWD is true.
-    // When IgnoreCWD is true, the module's content should not
-    // depend on the current working directory. However, if dwarf
-    // information is needed (when CGOpts.DwarfVersion is
-    // non-zero), then CGOpts.DebugCompilationDir must be
-    // populated, because otherwise the current working directory
-    // will be automatically embedded in the dwarf information in
-    // the pcm, contradicting the assumption that it is safe to
-    // ignore the CWD. Thus in such cases,
-    // CGOpts.DebugCompilationDir is explicitly set to a common
-    // directory.
-    // FIXME: It is still excessive to create a copy of
-    // CodeGenOpts for each module. Since we do not modify the
-    // CodeGenOpts otherwise per module, the following code
-    // ends up generating identical CodeGenOpts for each module
-    // with DebugCompilationDir pointing to the root directory.
-    // We can optimize this away by creating a _single_ copy of
-    // CodeGenOpts whose DebugCompilationDir points to the root
-    // directory and reuse it across modules.
-    BuildInvocation.getMutCodeGenOpts().DebugCompilationDir =
-        llvm::sys::path::root_path(CWD);
-  }
+  BuildInvocation.getMutCodeGenOpts().DebugCompilationDir.clear();
+  BuildInvocation.getMutCodeGenOpts().CoverageCompilationDir.clear();
 }
 
 static std::vector<std::string> splitString(std::string S, char Separator) {

diff --git a/clang/test/ClangScanDeps/modules-debug-dir.c b/clang/test/ClangScanDeps/modules-debug-dir.c
@@ -1,12 +1,16 @@
-// REQUIRES: shell
-
 // RUN: rm -rf %t
 // RUN: split-file %s %t
 // RUN: sed -e "s|DIR|%/t|g" %t/cdb.json.in > %t/cdb.json
 // RUN: clang-scan-deps -compilation-database %t/cdb.json -format \
 // RUN:   experimental-full -optimize-args=all > %t/result.json
 // RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck %s
 
+// RUN: %deps-to-rsp %t/result.json --module-name=mod > %t/mod.rsp
+// RUN: %clang @%t/mod.rsp -o %t/mod.pcm
+// RUN: llvm-dwarfdump --debug-info %t/mod.pcm | FileCheck %s --check-prefix=DWARF
+// DWARF: DW_TAG_compile_unit
+// DWARF-NOT: DW_AT_comp_dir
+
 //--- cdb.json.in
 [{
   "directory": "DIR",
@@ -28,5 +32,5 @@ module mod {
 // directory when current working directory optimization is in effect.
 // CHECK:  "modules": [
 // CHECK: "command-line": [
-// CHECK: "-fdebug-compilation-dir={{\/|.*:(\\)?}}",
+// CHECK-NOT: -fdebug-compilation-dir
 // CHECK:  "translation-units": [
diff --git a/clang/test/CodeGen/debug-info-abspath.c b/clang/test/CodeGen/debug-info-abspath.c
@@ -2,20 +2,15 @@
 // RUN: cp %s %t/UNIQUEISH_SENTINEL/debug-info-abspath.c
 
 // RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
+// RUN:   -fdebug-compilation-dir=%t/UNIQUEISH_SENTINEL/debug-info-abspath.c \
 // RUN:   %t/UNIQUEISH_SENTINEL/debug-info-abspath.c -emit-llvm -o - \
 // RUN:   | FileCheck %s
 
 // RUN: cp %s %t.c
 // RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
+// RUN:   -fdebug-compilation-dir=%t \
 // RUN:   %t.c -emit-llvm -o - | FileCheck %s --check-prefix=INTREE
 
-// RUN: cd %t/UNIQUEISH_SENTINEL
-// RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
-// RUN:   debug-info-abspath.c -emit-llvm -o - \
-// RUN:   | FileCheck %s --check-prefix=CURDIR
-// RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
-// RUN:   %s -emit-llvm -o - | FileCheck %s --check-prefix=CURDIR
-
 void foo(void) {}
 
 // Since %s is an absolute path, directory should be the common
@@ -28,7 +23,3 @@ void foo(void) {}
 
 // INTREE: = distinct !DISubprogram({{.*}}![[SPFILE:[0-9]+]]
 // INTREE: DIFile({{.*}}directory: "{{.+}}CodeGen{{.*}}")
-
-// CURDIR: = distinct !DICompileUnit({{.*}}file: ![[CUFILE:[0-9]+]]
-// CURDIR: ![[CUFILE]] = !DIFile({{.*}}directory: "{{.+}}UNIQUEISH_SENTINEL")
-
diff --git a/clang/test/CodeGen/debug-info-compilation-dir.c b/clang/test/CodeGen/debug-info-compilation-dir.c
@@ -7,3 +7,10 @@
 // RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited %s -o - | FileCheck -check-prefix=CHECK-DIR %s
 // CHECK-DIR: CodeGen
 
+/// Test path remapping.
+// RUN: %clang_cc1 -fdebug-compilation-dir=%S -main-file-name %s -emit-llvm -debug-info-kind=limited %s -o - | FileCheck -check-prefix=CHECK-ABS %s
+// CHECK-ABS: DIFile(filename: "{{.*}}debug-info-compilation-dir.c", directory: "{{.*}}CodeGen")
+
+// RUN: %clang_cc1 -main-file-name %s -emit-llvm -debug-info-kind=limited %s -o - | FileCheck -check-prefix=CHECK-NOMAP %s
+// CHECK-NOMAP: DIFile(filename: "{{.*}}debug-info-compilation-dir.c", directory: "")
+
diff --git a/clang/test/CodeGen/debug-prefix-map.c b/clang/test/CodeGen/debug-prefix-map.c
@@ -12,6 +12,7 @@
 // RUN: rm -rf %t && mkdir -p %t/a/b && cp %s %t/a/b/c.c
 // RUN: %clang_cc1 -emit-llvm -debug-info-kind=standalone -I%S -fdebug-prefix-map=%t/a/b=y -fdebug-prefix-map=%t/a=x %t/a/b/c.c -o - | FileCheck %s --check-prefix=CHECK-X
 // RUN: %clang_cc1 -emit-llvm -debug-info-kind=standalone -I%S -fdebug-prefix-map=%t/a=x -fdebug-prefix-map=%t/a/b=y %t/a/b/c.c -o - | FileCheck %s --check-prefix=CHECK-Y
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=standalone -I%S -main-file-name %t/a/b/c.c -fdebug-compilation-dir=%t/a -fdebug-prefix-map=%t/a=x -fdebug-prefix-map=%t/a/b=y %t/a/b/c.c -o - | FileCheck %s --check-prefix=CHECK-REMAP-Y
 
 #include "Inputs/stdio.h"
 
@@ -26,9 +27,9 @@ void test_rewrite_includes(void) {
   vprintf("string", argp);
 }
 
-// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "{{/|.:\\\\}}UNLIKELY_PATH{{/|\\\\}}empty{{/|\\\\}}<stdin>",
 // CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "{{/|.:\\\\}}UNLIKELY_PATH{{/|\\\\}}empty{{/|\\\\}}{{.*}}",
 // CHECK-NO-MAIN-FILE-NAME-SAME:    directory: "")
+// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "{{/|.:\\\\}}UNLIKELY_PATH{{/|\\\\}}empty{{/|\\\\}}<stdin>",
 // CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "{{/|.:\\\\}}UNLIKELY_PATH{{/|\\\\}}empty{{/|\\\\}}Inputs{{/|\\\\}}stdio.h",
 // CHECK-NO-MAIN-FILE-NAME-SAME:    directory: "")
 // CHECK-NO-MAIN-FILE-NAME-NOT: !DIFile(filename:
@@ -54,3 +55,5 @@ void test_rewrite_includes(void) {
 
 // CHECK-X: !DIFile(filename: "x{{/|\\\\}}b{{/|\\\\}}c.c", directory: "")
 // CHECK-Y: !DIFile(filename: "y{{/|\\\\}}c.c", directory: "")
+
+// CHECK-REMAP-Y: !DIFile(filename: "y{{/|\\\\}}c.c", directory: "x")
diff --git a/clang/test/CodeGenCXX/debug-info-function-context.cpp b/clang/test/CodeGenCXX/debug-info-function-context.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited -triple x86_64-pc-linux-gnu %s \
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited -triple x86_64-pc-linux-gnu %s -fdebug-compilation-dir=%S \
 // RUN:     -dwarf-version=5 -main-file-name debug-info-function-context.cpp  -o - | FileCheck %s
 
 struct C {

diff --git a/clang/test/CodeGenCXX/difile_entry.cpp b/clang/test/CodeGenCXX/difile_entry.cpp
@@ -3,7 +3,7 @@
 /// Test that we canonicalize the DIFile.
 // RUN: rm -rf %t && mkdir %t && cd %t
 // RUN: cp %s .
-// RUN: %clang_cc1 -triple %itanium_abi_triple -main-file-name difile_entry.cpp -debug-info-kind=limited %t/difile_entry.cpp -std=c++11 -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -triple %itanium_abi_triple -main-file-name difile_entry.cpp -fdebug-compilation-dir=%t -debug-info-kind=limited %t/difile_entry.cpp -std=c++11 -emit-llvm -o - | FileCheck %s
 int x();
 static int i = x();
 

diff --git a/clang/test/PCH/debug-info-pch-path.c b/clang/test/PCH/debug-info-pch-path.c
@@ -65,7 +65,8 @@
 // RUN: %clang_cc1 -debug-info-kind=standalone                  \
 // RUN:     -dwarf-ext-refs -fmodule-format=obj                 \
 // RUN:     -triple %itanium_abi_triple                         \
-// RUN:     -include-pch %t/prefix.pch %s -emit-llvm -o %t.abs.ll %s
+// RUN:     -include-pch %t/prefix.pch %s -emit-llvm            \
+// RUN:     -fdebug-compilation-dir=%t -o %t.abs.ll %s
 // RUN: cat %t.abs.ll | FileCheck %s --check-prefix=CHECK-ABS
 
 // CHECK-ABS: !DICompileUnit

diff --git a/clang/test/Profile/coverage-prefix-map.c b/clang/test/Profile/coverage-prefix-map.c
@@ -25,7 +25,7 @@
 // COVERAGE-PREFIX-MAP-ORDER: @__llvm_coverage_mapping = {{.*"\\02.*newpath.*root.*nested.*coverage-prefix-map\.c}}
 
 // Test that last -fcoverage-prefix-map option (-fcoverage-prefix-map=%/t/root=.) is applied.
-// RUN: %clang_cc1 -fprofile-instrument=clang -fcoverage-mapping -emit-llvm -mllvm -enable-name-compression=false -main-file-name coverage-prefix-map.c %t/root/nested/coverage-prefix-map.c -fcoverage-prefix-map==newpath -fcoverage-prefix-map=%/t/root=. -o - | FileCheck --check-prefix=COVERAGE-PREFIX-MAP-REORDER %s
+// RUN: %clang_cc1 -fprofile-instrument=clang -fcoverage-mapping -emit-llvm -mllvm -enable-name-compression=false -main-file-name coverage-prefix-map.c %t/root/nested/coverage-prefix-map.c -fcoverage-compilation-dir=%t/root -fcoverage-prefix-map==newpath -fcoverage-prefix-map=%/t/root=. -o - | FileCheck --check-prefix=COVERAGE-PREFIX-MAP-REORDER %s
 // COVERAGE-PREFIX-MAP-REORDER: @__llvm_coverage_mapping =
 // COVERAGE-PREFIX-MAP-REORDER-NOT: newpath
 // COVERAGE-PREFIX-MAP-REORDER-SAME: nested{{.*coverage-prefix-map\.c}}
diff --git a/clang/unittests/Frontend/CodeGenActionTest.cpp b/clang/unittests/Frontend/CodeGenActionTest.cpp
@@ -76,40 +76,4 @@ TEST(CodeGenTest, CodeGenFromIRMemBuffer) {
   bool Success = Compiler.ExecuteAction(Action);
   EXPECT_TRUE(Success);
 }
-
-TEST(CodeGenTest, DebugInfoCWDCodeGen) {
-  // Check that debug info is accessing the current working directory from the
-  // VFS instead of calling \p llvm::sys::fs::current_path() directly.
-
-  auto Sept = llvm::sys::path::get_separator();
-  auto VFS = std::make_unique<llvm::vfs::InMemoryFileSystem>();
-  VFS->setCurrentWorkingDirectory(
-      std::string(llvm::formatv("{0}in-memory-fs-cwd", Sept)));
-  std::string TestPath =
-      std::string(llvm::formatv("{0}in-memory-fs-cwd{0}test.cpp", Sept));
-  VFS->addFile(TestPath, 0, llvm::MemoryBuffer::getMemBuffer("int x;\n"));
-
-  auto Invocation = std::make_shared<CompilerInvocation>();
-  Invocation->getFrontendOpts().Inputs.push_back(
-      FrontendInputFile("test.cpp", Language::CXX));
-  Invocation->getFrontendOpts().ProgramAction = EmitLLVM;
-  Invocation->getTargetOpts().Triple = "x86_64-unknown-linux-gnu";
-  Invocation->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
-  CompilerInstance Compiler(std::move(Invocation));
-
-  SmallString<256> IRBuffer;
-  Compiler.setOutputStream(std::make_unique<raw_svector_ostream>(IRBuffer));
-  Compiler.createDiagnostics(*VFS);
-  Compiler.createFileManager(std::move(VFS));
-
-  EmitLLVMAction Action;
-  bool Success = Compiler.ExecuteAction(Action);
-  EXPECT_TRUE(Success);
-
-  SmallString<128> RealCWD;
-  llvm::sys::fs::current_path(RealCWD);
-  EXPECT_TRUE(!RealCWD.empty());
-  EXPECT_FALSE(IRBuffer.str().contains(RealCWD));
-  EXPECT_TRUE(IRBuffer.str().contains("in-memory-fs-cwd"));
-}
 }