[SystemZ][z/OS] Add new openFileForReadBinary function, and pass IsText parameter to getBufferForFile #111723
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@llvm/pr-subscribers-llvm-support @llvm/pr-subscribers-clang Author: Abhina Sree (abhina-sree) ChangesThis patch adds an IsText parameter to the following getBufferForFile, getBufferForFileImpl. We introduce a new virtual function openFileForReadBinary which defaults to openFileForRead except in RealFileSystem which uses the OF_None flag instead of OF_Text. The default is set to OF_Text instead of OF_None, this change in value does not affect any other platforms other than z/OS. Setting this parameter correctly is required to open files on z/OS in the correct encoding. The IsText parameter is based on the context of where we open files, for example, in the ASTReader, HeaderMap requires that files always be opened in binary even though they might be tagged as text. Full diff: https://github.com/llvm/llvm-project/pull/111723.diff 6 Files Affected:
diff --git a/clang/include/clang/Basic/FileManager.h b/clang/include/clang/Basic/FileManager.h
index ce4e8c1fbe16eb..d987fb05a94a37 100644
--- a/clang/include/clang/Basic/FileManager.h
+++ b/clang/include/clang/Basic/FileManager.h
@@ -292,21 +292,21 @@ class FileManager : public RefCountedBase<FileManager> {
/// MemoryBuffer if successful, otherwise returning null.
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(FileEntryRef Entry, bool isVolatile = false,
- bool RequiresNullTerminator = true,
+ bool RequiresNullTerminator = true, bool IsText = true,
std::optional<int64_t> MaybeLimit = std::nullopt);
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(StringRef Filename, bool isVolatile = false,
- bool RequiresNullTerminator = true,
+ bool RequiresNullTerminator = true, bool IsText = true,
std::optional<int64_t> MaybeLimit = std::nullopt) const {
return getBufferForFileImpl(Filename,
/*FileSize=*/MaybeLimit.value_or(-1),
- isVolatile, RequiresNullTerminator);
+ isVolatile, RequiresNullTerminator, IsText);
}
private:
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFileImpl(StringRef Filename, int64_t FileSize, bool isVolatile,
- bool RequiresNullTerminator) const;
+ bool RequiresNullTerminator, bool IsText) const;
DirectoryEntry *&getRealDirEntry(const llvm::vfs::Status &Status);
diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp
index 6097b85a03064b..27075cefafdc2f 100644
--- a/clang/lib/Basic/FileManager.cpp
+++ b/clang/lib/Basic/FileManager.cpp
@@ -530,7 +530,7 @@ void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
FileManager::getBufferForFile(FileEntryRef FE, bool isVolatile,
- bool RequiresNullTerminator,
+ bool RequiresNullTerminator, bool IsText,
std::optional<int64_t> MaybeLimit) {
const FileEntry *Entry = &FE.getFileEntry();
// If the content is living on the file entry, return a reference to it.
@@ -558,21 +558,21 @@ FileManager::getBufferForFile(FileEntryRef FE, bool isVolatile,
// Otherwise, open the file.
return getBufferForFileImpl(Filename, FileSize, isVolatile,
- RequiresNullTerminator);
+ RequiresNullTerminator, IsText);
}
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
FileManager::getBufferForFileImpl(StringRef Filename, int64_t FileSize,
- bool isVolatile,
- bool RequiresNullTerminator) const {
+ bool isVolatile, bool RequiresNullTerminator,
+ bool IsText) const {
if (FileSystemOpts.WorkingDir.empty())
return FS->getBufferForFile(Filename, FileSize, RequiresNullTerminator,
- isVolatile);
+ isVolatile, IsText);
SmallString<128> FilePath(Filename);
FixupRelativePath(FilePath);
return FS->getBufferForFile(FilePath, FileSize, RequiresNullTerminator,
- isVolatile);
+ isVolatile, IsText);
}
/// getStatValue - Get the 'stat' information for the specified path,
diff --git a/clang/lib/Lex/HeaderMap.cpp b/clang/lib/Lex/HeaderMap.cpp
index 00bf880726ee3e..35c68b304a4523 100644
--- a/clang/lib/Lex/HeaderMap.cpp
+++ b/clang/lib/Lex/HeaderMap.cpp
@@ -54,7 +54,9 @@ std::unique_ptr<HeaderMap> HeaderMap::Create(FileEntryRef FE, FileManager &FM) {
unsigned FileSize = FE.getSize();
if (FileSize <= sizeof(HMapHeader)) return nullptr;
- auto FileBuffer = FM.getBufferForFile(FE);
+ auto FileBuffer =
+ FM.getBufferForFile(FE, /*IsVolatile=*/false,
+ /*RequiresNullTerminator=*/true, /*IsText=*/false);
if (!FileBuffer || !*FileBuffer)
return nullptr;
bool NeedsByteSwap;
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 5c4f8d0e9c46cd..769b85dc318072 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -5333,7 +5333,8 @@ std::string ASTReader::getOriginalSourceFile(
const PCHContainerReader &PCHContainerRdr, DiagnosticsEngine &Diags) {
// Open the AST file.
auto Buffer = FileMgr.getBufferForFile(ASTFileName, /*IsVolatile=*/false,
- /*RequiresNullTerminator=*/false);
+ /*RequiresNullTerminator=*/false,
+ /*IsText=*/false);
if (!Buffer) {
Diags.Report(diag::err_fe_unable_to_read_pch_file)
<< ASTFileName << Buffer.getError().message();
diff --git a/llvm/include/llvm/Support/VirtualFileSystem.h b/llvm/include/llvm/Support/VirtualFileSystem.h
index 2531c075f262d7..a94e285a806f2c 100644
--- a/llvm/include/llvm/Support/VirtualFileSystem.h
+++ b/llvm/include/llvm/Support/VirtualFileSystem.h
@@ -271,15 +271,24 @@ class FileSystem : public llvm::ThreadSafeRefCountedBase<FileSystem>,
/// Get the status of the entry at \p Path, if one exists.
virtual llvm::ErrorOr<Status> status(const Twine &Path) = 0;
- /// Get a \p File object for the file at \p Path, if one exists.
+ /// Get a \p File object for the text file at \p Path, if one exists.
virtual llvm::ErrorOr<std::unique_ptr<File>>
openFileForRead(const Twine &Path) = 0;
+ /// Get a \p File objct for the binary file at \p Path, if one exists.
+ /// This function should be called instead of openFileForRead if the file
+ /// should be opened as a binary file.
+ virtual llvm::ErrorOr<std::unique_ptr<File>>
+ openFileForReadBinary(const Twine &Path) {
+ return openFileForRead(Path);
+ }
+
/// This is a convenience method that opens a file, gets its content and then
/// closes the file.
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(const Twine &Name, int64_t FileSize = -1,
- bool RequiresNullTerminator = true, bool IsVolatile = false);
+ bool RequiresNullTerminator = true, bool IsVolatile = false,
+ bool IsText = true);
/// Get a directory_iterator for \p Dir.
/// \note The 'end' iterator is directory_iterator().
diff --git a/llvm/lib/Support/VirtualFileSystem.cpp b/llvm/lib/Support/VirtualFileSystem.cpp
index 928c0b5a24ed65..be7c140ce12406 100644
--- a/llvm/lib/Support/VirtualFileSystem.cpp
+++ b/llvm/lib/Support/VirtualFileSystem.cpp
@@ -117,8 +117,12 @@ FileSystem::~FileSystem() = default;
ErrorOr<std::unique_ptr<MemoryBuffer>>
FileSystem::getBufferForFile(const llvm::Twine &Name, int64_t FileSize,
- bool RequiresNullTerminator, bool IsVolatile) {
- auto F = openFileForRead(Name);
+ bool RequiresNullTerminator, bool IsVolatile,
+ bool IsText) {
+ auto openFileFunctionPointer = &FileSystem::openFileForRead;
+ if (!IsText)
+ openFileFunctionPointer = &FileSystem::openFileForReadBinary;
+ auto F = (this->*openFileFunctionPointer)(Name);
if (!F)
return F.getError();
@@ -279,6 +283,8 @@ class RealFileSystem : public FileSystem {
ErrorOr<Status> status(const Twine &Path) override;
ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
+ ErrorOr<std::unique_ptr<File>>
+ openFileForReadBinary(const Twine &Path) override;
directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override;
@@ -324,6 +330,17 @@ ErrorOr<Status> RealFileSystem::status(const Twine &Path) {
ErrorOr<std::unique_ptr<File>>
RealFileSystem::openFileForRead(const Twine &Name) {
+ SmallString<256> RealName, Storage;
+ Expected<file_t> FDOrErr = sys::fs::openNativeFileForRead(
+ adjustPath(Name, Storage), sys::fs::OF_Text, &RealName);
+ if (!FDOrErr)
+ return errorToErrorCode(FDOrErr.takeError());
+ return std::unique_ptr<File>(
+ new RealFile(*FDOrErr, Name.str(), RealName.str()));
+}
+
+ErrorOr<std::unique_ptr<File>>
+RealFileSystem::openFileForReadBinary(const Twine &Name) {
SmallString<256> RealName, Storage;
Expected<file_t> FDOrErr = sys::fs::openNativeFileForRead(
adjustPath(Name, Storage), sys::fs::OF_None, &RealName);
|
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@llvm/pr-subscribers-clang-modules Author: Abhina Sree (abhina-sree) ChangesThis patch adds an IsText parameter to the following getBufferForFile, getBufferForFileImpl. We introduce a new virtual function openFileForReadBinary which defaults to openFileForRead except in RealFileSystem which uses the OF_None flag instead of OF_Text. The default is set to OF_Text instead of OF_None, this change in value does not affect any other platforms other than z/OS. Setting this parameter correctly is required to open files on z/OS in the correct encoding. The IsText parameter is based on the context of where we open files, for example, in the ASTReader, HeaderMap requires that files always be opened in binary even though they might be tagged as text. Full diff: https://github.com/llvm/llvm-project/pull/111723.diff 6 Files Affected:
diff --git a/clang/include/clang/Basic/FileManager.h b/clang/include/clang/Basic/FileManager.h
index ce4e8c1fbe16eb..d987fb05a94a37 100644
--- a/clang/include/clang/Basic/FileManager.h
+++ b/clang/include/clang/Basic/FileManager.h
@@ -292,21 +292,21 @@ class FileManager : public RefCountedBase<FileManager> {
/// MemoryBuffer if successful, otherwise returning null.
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(FileEntryRef Entry, bool isVolatile = false,
- bool RequiresNullTerminator = true,
+ bool RequiresNullTerminator = true, bool IsText = true,
std::optional<int64_t> MaybeLimit = std::nullopt);
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(StringRef Filename, bool isVolatile = false,
- bool RequiresNullTerminator = true,
+ bool RequiresNullTerminator = true, bool IsText = true,
std::optional<int64_t> MaybeLimit = std::nullopt) const {
return getBufferForFileImpl(Filename,
/*FileSize=*/MaybeLimit.value_or(-1),
- isVolatile, RequiresNullTerminator);
+ isVolatile, RequiresNullTerminator, IsText);
}
private:
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFileImpl(StringRef Filename, int64_t FileSize, bool isVolatile,
- bool RequiresNullTerminator) const;
+ bool RequiresNullTerminator, bool IsText) const;
DirectoryEntry *&getRealDirEntry(const llvm::vfs::Status &Status);
diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp
index 6097b85a03064b..27075cefafdc2f 100644
--- a/clang/lib/Basic/FileManager.cpp
+++ b/clang/lib/Basic/FileManager.cpp
@@ -530,7 +530,7 @@ void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
FileManager::getBufferForFile(FileEntryRef FE, bool isVolatile,
- bool RequiresNullTerminator,
+ bool RequiresNullTerminator, bool IsText,
std::optional<int64_t> MaybeLimit) {
const FileEntry *Entry = &FE.getFileEntry();
// If the content is living on the file entry, return a reference to it.
@@ -558,21 +558,21 @@ FileManager::getBufferForFile(FileEntryRef FE, bool isVolatile,
// Otherwise, open the file.
return getBufferForFileImpl(Filename, FileSize, isVolatile,
- RequiresNullTerminator);
+ RequiresNullTerminator, IsText);
}
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
FileManager::getBufferForFileImpl(StringRef Filename, int64_t FileSize,
- bool isVolatile,
- bool RequiresNullTerminator) const {
+ bool isVolatile, bool RequiresNullTerminator,
+ bool IsText) const {
if (FileSystemOpts.WorkingDir.empty())
return FS->getBufferForFile(Filename, FileSize, RequiresNullTerminator,
- isVolatile);
+ isVolatile, IsText);
SmallString<128> FilePath(Filename);
FixupRelativePath(FilePath);
return FS->getBufferForFile(FilePath, FileSize, RequiresNullTerminator,
- isVolatile);
+ isVolatile, IsText);
}
/// getStatValue - Get the 'stat' information for the specified path,
diff --git a/clang/lib/Lex/HeaderMap.cpp b/clang/lib/Lex/HeaderMap.cpp
index 00bf880726ee3e..35c68b304a4523 100644
--- a/clang/lib/Lex/HeaderMap.cpp
+++ b/clang/lib/Lex/HeaderMap.cpp
@@ -54,7 +54,9 @@ std::unique_ptr<HeaderMap> HeaderMap::Create(FileEntryRef FE, FileManager &FM) {
unsigned FileSize = FE.getSize();
if (FileSize <= sizeof(HMapHeader)) return nullptr;
- auto FileBuffer = FM.getBufferForFile(FE);
+ auto FileBuffer =
+ FM.getBufferForFile(FE, /*IsVolatile=*/false,
+ /*RequiresNullTerminator=*/true, /*IsText=*/false);
if (!FileBuffer || !*FileBuffer)
return nullptr;
bool NeedsByteSwap;
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 5c4f8d0e9c46cd..769b85dc318072 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -5333,7 +5333,8 @@ std::string ASTReader::getOriginalSourceFile(
const PCHContainerReader &PCHContainerRdr, DiagnosticsEngine &Diags) {
// Open the AST file.
auto Buffer = FileMgr.getBufferForFile(ASTFileName, /*IsVolatile=*/false,
- /*RequiresNullTerminator=*/false);
+ /*RequiresNullTerminator=*/false,
+ /*IsText=*/false);
if (!Buffer) {
Diags.Report(diag::err_fe_unable_to_read_pch_file)
<< ASTFileName << Buffer.getError().message();
diff --git a/llvm/include/llvm/Support/VirtualFileSystem.h b/llvm/include/llvm/Support/VirtualFileSystem.h
index 2531c075f262d7..a94e285a806f2c 100644
--- a/llvm/include/llvm/Support/VirtualFileSystem.h
+++ b/llvm/include/llvm/Support/VirtualFileSystem.h
@@ -271,15 +271,24 @@ class FileSystem : public llvm::ThreadSafeRefCountedBase<FileSystem>,
/// Get the status of the entry at \p Path, if one exists.
virtual llvm::ErrorOr<Status> status(const Twine &Path) = 0;
- /// Get a \p File object for the file at \p Path, if one exists.
+ /// Get a \p File object for the text file at \p Path, if one exists.
virtual llvm::ErrorOr<std::unique_ptr<File>>
openFileForRead(const Twine &Path) = 0;
+ /// Get a \p File objct for the binary file at \p Path, if one exists.
+ /// This function should be called instead of openFileForRead if the file
+ /// should be opened as a binary file.
+ virtual llvm::ErrorOr<std::unique_ptr<File>>
+ openFileForReadBinary(const Twine &Path) {
+ return openFileForRead(Path);
+ }
+
/// This is a convenience method that opens a file, gets its content and then
/// closes the file.
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(const Twine &Name, int64_t FileSize = -1,
- bool RequiresNullTerminator = true, bool IsVolatile = false);
+ bool RequiresNullTerminator = true, bool IsVolatile = false,
+ bool IsText = true);
/// Get a directory_iterator for \p Dir.
/// \note The 'end' iterator is directory_iterator().
diff --git a/llvm/lib/Support/VirtualFileSystem.cpp b/llvm/lib/Support/VirtualFileSystem.cpp
index 928c0b5a24ed65..be7c140ce12406 100644
--- a/llvm/lib/Support/VirtualFileSystem.cpp
+++ b/llvm/lib/Support/VirtualFileSystem.cpp
@@ -117,8 +117,12 @@ FileSystem::~FileSystem() = default;
ErrorOr<std::unique_ptr<MemoryBuffer>>
FileSystem::getBufferForFile(const llvm::Twine &Name, int64_t FileSize,
- bool RequiresNullTerminator, bool IsVolatile) {
- auto F = openFileForRead(Name);
+ bool RequiresNullTerminator, bool IsVolatile,
+ bool IsText) {
+ auto openFileFunctionPointer = &FileSystem::openFileForRead;
+ if (!IsText)
+ openFileFunctionPointer = &FileSystem::openFileForReadBinary;
+ auto F = (this->*openFileFunctionPointer)(Name);
if (!F)
return F.getError();
@@ -279,6 +283,8 @@ class RealFileSystem : public FileSystem {
ErrorOr<Status> status(const Twine &Path) override;
ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
+ ErrorOr<std::unique_ptr<File>>
+ openFileForReadBinary(const Twine &Path) override;
directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override;
@@ -324,6 +330,17 @@ ErrorOr<Status> RealFileSystem::status(const Twine &Path) {
ErrorOr<std::unique_ptr<File>>
RealFileSystem::openFileForRead(const Twine &Name) {
+ SmallString<256> RealName, Storage;
+ Expected<file_t> FDOrErr = sys::fs::openNativeFileForRead(
+ adjustPath(Name, Storage), sys::fs::OF_Text, &RealName);
+ if (!FDOrErr)
+ return errorToErrorCode(FDOrErr.takeError());
+ return std::unique_ptr<File>(
+ new RealFile(*FDOrErr, Name.str(), RealName.str()));
+}
+
+ErrorOr<std::unique_ptr<File>>
+RealFileSystem::openFileForReadBinary(const Twine &Name) {
SmallString<256> RealName, Storage;
Expected<file_t> FDOrErr = sys::fs::openNativeFileForRead(
adjustPath(Name, Storage), sys::fs::OF_None, &RealName);
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perry-ca
reviewed
Oct 9, 2024
…xt parameter to getBufferForFile
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perry-ca
reviewed
Oct 9, 2024
| @@ -302,6 +305,17 @@ class RealFileSystem : public FileSystem { | |||
| return Storage; | |||
| } | |||
|
|
|||
| ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Name, | |||
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Thanks, Could you mark this as static.
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I don't think I'm able to mark it static because it calls adjustPath which is non-static
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np. I was misreading the diff. I didn't see it was a private member function. It looked like a file scope function. I was thinking file scope static, not static member.
kadircet
requested changes
Oct 10, 2024
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@abhina-sree do you plan to modify embed in this PR? |
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The related lit tests all seem to be passing on z/OS right now. I'm guessing it might be because we get the contents as binary here https://github.com/llvm/llvm-project/blob/main/clang/lib/Lex/PPDirectives.cpp#L3990. I'll have to do a bit more investigation, but it seems to be working without modifications so I don't think any changes are needed. If there are changes required, I will make them in a separate PR |
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✅ With the latest revision this PR passed the C/C++ code formatter. |
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Actually Sean has pointed out that if we pass in non-ascii inputs, the tests do in fact fail. So I will look into passing the IsText parameter in the necessary functions. Thanks for pointing this out! |
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@cor3ntin, I've added support for #embed handling now, I've added a z/OS only testcase clang/test/Preprocessor/embed_zos.c which is a copy of clang/test/Preprocessor/embed_art.c except it changes the file tag to be non-ascii which is now working with the latest commit. |
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…d testcase for zos
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LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/73/builds/7345 Here is the relevant piece of the build log for the reference |
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This patch adds an IsText parameter to the following getBufferForFile, getBufferForFileImpl. We introduce a new virtual function openFileForReadBinary which defaults to openFileForRead except in RealFileSystem which uses the OF_None flag instead of OF_Text.
The default is set to OF_Text instead of OF_None, this change in value does not affect any other platforms other than z/OS. Setting this parameter correctly is required to open files on z/OS in the correct encoding. The IsText parameter is based on the context of where we open files, for example, in the ASTReader, HeaderMap requires that files always be opened in binary even though they might be tagged as text.