✨ [Sema, Lex, Parse] Preprocessor embed in C and C++ (and Obj-C and Obj-C++ by-proxy) #68620
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@llvm/pr-subscribers-clang-static-analyzer-1 @llvm/pr-subscribers-llvm-support ChangesThis pull request implements the entirety of the now-accepted N3017 - Preprocessor Embed and its sister C++ paper p1967. It implements everything in the specification, and includes an implementation that drastically improves the time it takes to embed data in specific scenarios (the initialization of character type arrays). The mechanisms used to do this are used under the "as-if" rule, and in general when the system cannot detect it is initializing an array object in a variable declaration, will simply expand the list out to a sequence of numbers. There are likely places where the Images are a dry run of a recently built clang and LLVM on Release mode (not RelWithDebInfo) on Windows, under the following properties: OS Name: Microsoft Windows 10 Pro All of the added tests pass under the above machine properties. I have no intention of following up on this PR. I am too tired to carry it to fruition. Pick this apart, take from it what you want, or reimplement it entirely. (I will be unsubscribing from this immediately after posting.) Good luck ✌!
Patch is 1.33 MiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/68620.diff 82 Files Affected:
diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
index 9b52c58be41e7f7..1b88905da3b8597 100644
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@@ -300,6 +300,7 @@ configure_file(
${CMAKE_CURRENT_BINARY_DIR}/include/clang/Basic/Version.inc)
# Add appropriate flags for GCC
+option(CLANG_ENABLE_PEDANTIC "Compile with pedantic enabled." ON)
if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-common -Woverloaded-virtual")
if (NOT "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
@@ -307,7 +308,7 @@ if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
endif ()
# Enable -pedantic for Clang even if it's not enabled for LLVM.
- if (NOT LLVM_ENABLE_PEDANTIC)
+ if (NOT LLVM_ENABLE_PEDANTIC AND CLANG_ENABLE_PEDANTIC)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pedantic -Wno-long-long")
endif ()
diff --git a/clang/include/clang/AST/Expr.h b/clang/include/clang/AST/Expr.h
index b69c616b0090365..9303307fd6a8af5 100644
--- a/clang/include/clang/AST/Expr.h
+++ b/clang/include/clang/AST/Expr.h
@@ -4805,6 +4805,58 @@ class SourceLocExpr final : public Expr {
friend class ASTStmtReader;
};
+/// Represents a function call to __builtin_pp_embed().
+class PPEmbedExpr final : public Expr {
+ SourceLocation BuiltinLoc, RParenLoc;
+ DeclContext *ParentContext;
+ StringLiteral *Filename;
+ StringLiteral *BinaryData;
+
+public:
+ enum Action {
+ NotFound,
+ FoundOne,
+ Expanded,
+ };
+
+ PPEmbedExpr(const ASTContext &Ctx, QualType ResultTy, StringLiteral* Filename, StringLiteral* BinaryData,
+ SourceLocation BLoc, SourceLocation RParenLoc,
+ DeclContext *Context);
+
+ /// Build an empty call expression.
+ explicit PPEmbedExpr(EmptyShell Empty)
+ : Expr(SourceLocExprClass, Empty) {}
+
+ /// If the PPEmbedExpr has been resolved return the subexpression
+ /// representing the resolved value. Otherwise return null.
+ const DeclContext *getParentContext() const { return ParentContext; }
+ DeclContext *getParentContext() { return ParentContext; }
+
+ SourceLocation getLocation() const { return BuiltinLoc; }
+ SourceLocation getBeginLoc() const { return BuiltinLoc; }
+ SourceLocation getEndLoc() const { return RParenLoc; }
+
+ StringLiteral *getFilenameStringLiteral() const { return Filename; }
+ StringLiteral *getDataStringLiteral() const { return BinaryData; }
+
+ size_t getDataElementCount(ASTContext &Context) const;
+
+ child_range children() {
+ return child_range(child_iterator(), child_iterator());
+ }
+
+ const_child_range children() const {
+ return const_child_range(child_iterator(), child_iterator());
+ }
+
+ static bool classof(const Stmt *T) {
+ return T->getStmtClass() == PPEmbedExprClass;
+ }
+
+private:
+ friend class ASTStmtReader;
+};
+
/// Describes an C or C++ initializer list.
///
/// InitListExpr describes an initializer list, which can be used to
diff --git a/clang/include/clang/AST/RecursiveASTVisitor.h b/clang/include/clang/AST/RecursiveASTVisitor.h
index 3dd23eb38eeabfc..6b7211bb0a0d3f1 100644
--- a/clang/include/clang/AST/RecursiveASTVisitor.h
+++ b/clang/include/clang/AST/RecursiveASTVisitor.h
@@ -2809,6 +2809,7 @@ DEF_TRAVERSE_STMT(ShuffleVectorExpr, {})
DEF_TRAVERSE_STMT(ConvertVectorExpr, {})
DEF_TRAVERSE_STMT(StmtExpr, {})
DEF_TRAVERSE_STMT(SourceLocExpr, {})
+DEF_TRAVERSE_STMT(PPEmbedExpr, {})
DEF_TRAVERSE_STMT(UnresolvedLookupExpr, {
TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
diff --git a/clang/include/clang/Basic/Builtins.def b/clang/include/clang/Basic/Builtins.def
index 6ea8484606cfd5d..0dfc6456daf059a 100644
--- a/clang/include/clang/Basic/Builtins.def
+++ b/clang/include/clang/Basic/Builtins.def
@@ -1766,6 +1766,9 @@ BUILTIN(__builtin_ms_va_copy, "vc*&c*&", "n")
// Arithmetic Fence: to prevent FP reordering and reassociation optimizations
LANGBUILTIN(__arithmetic_fence, "v.", "tE", ALL_LANGUAGES)
+// preprocessor embed builtin
+LANGBUILTIN(__builtin_pp_embed, "v.", "tE", ALL_LANGUAGES)
+
#undef BUILTIN
#undef LIBBUILTIN
#undef LANGBUILTIN
diff --git a/clang/include/clang/Basic/DiagnosticCommonKinds.td b/clang/include/clang/Basic/DiagnosticCommonKinds.td
index f2df283c74829f6..4df86e35eebde38 100644
--- a/clang/include/clang/Basic/DiagnosticCommonKinds.td
+++ b/clang/include/clang/Basic/DiagnosticCommonKinds.td
@@ -59,6 +59,9 @@ def err_expected_string_literal : Error<"expected string literal "
"'external_source_symbol' attribute|"
"as argument of '%1' attribute}0">;
+def err_builtin_pp_embed_invalid_argument : Error<
+ "invalid argument to '__builtin_pp_embed': %0">;
+
def err_invalid_string_udl : Error<
"string literal with user-defined suffix cannot be used here">;
def err_invalid_character_udl : Error<
@@ -80,6 +83,9 @@ def err_expected : Error<"expected %0">;
def err_expected_either : Error<"expected %0 or %1">;
def err_expected_after : Error<"expected %1 after %0">;
+def err_builtin_pp_embed_invalid_location : Error<
+ "'__builtin_pp_embed' in invalid location: %0%select{|%2}1">;
+
def err_param_redefinition : Error<"redefinition of parameter %0">;
def warn_method_param_redefinition : Warning<"redefinition of method parameter %0">;
def warn_method_param_declaration : Warning<"redeclaration of method parameter %0">,
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 0b09c002191848a..7ebea56891d4654 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -708,6 +708,12 @@ def ReservedIdAsMacro : DiagGroup<"reserved-macro-identifier">;
def ReservedIdAsMacroAlias : DiagGroup<"reserved-id-macro", [ReservedIdAsMacro]>;
def RestrictExpansionMacro : DiagGroup<"restrict-expansion">;
def FinalMacro : DiagGroup<"final-macro">;
+// Warnings about unknown preprocessor parameters (e.g. `#embed` and extensions)
+def UnsupportedDirective : DiagGroup<"unsupported-directive">;
+def UnknownDirectiveParameters : DiagGroup<"unknown-directive-parameters">;
+def IgnoredDirectiveParameters : DiagGroup<"ignored-directive-parameters">;
+def DirectiveParameters : DiagGroup<"directive-parameters",
+ [UnknownDirectiveParameters, IgnoredDirectiveParameters]>;
// Just silence warnings about -Wstrict-aliasing for now.
def : DiagGroup<"strict-aliasing=0">;
@@ -715,6 +721,7 @@ def : DiagGroup<"strict-aliasing=1">;
def : DiagGroup<"strict-aliasing=2">;
def : DiagGroup<"strict-aliasing">;
+
// Just silence warnings about -Wstrict-overflow for now.
def : DiagGroup<"strict-overflow=0">;
def : DiagGroup<"strict-overflow=1">;
diff --git a/clang/include/clang/Basic/DiagnosticLexKinds.td b/clang/include/clang/Basic/DiagnosticLexKinds.td
index 940cca67368492f..4490f40806b0345 100644
--- a/clang/include/clang/Basic/DiagnosticLexKinds.td
+++ b/clang/include/clang/Basic/DiagnosticLexKinds.td
@@ -422,6 +422,22 @@ def warn_cxx23_compat_warning_directive : Warning<
def warn_c23_compat_warning_directive : Warning<
"#warning is incompatible with C standards before C23">,
InGroup<CPre23Compat>, DefaultIgnore;
+def warn_c23_pp_embed : Warning<
+ "'__has_embed' is a C23 extension">,
+ InGroup<CPre23Compat>,
+ DefaultIgnore;
+def warn_c23_pp_has_embed : Warning<
+ "'__has_embed' is a C23 extension">,
+ InGroup<CPre23Compat>,
+ DefaultIgnore;
+def warn_cxx26_pp_embed : Warning<
+ "'__has_embed' is a C++26 extension">,
+ InGroup<CXXPre26Compat>,
+ DefaultIgnore;
+def warn_cxx26_pp_has_embed : Warning<
+ "'__has_embed' is a C++26 extension">,
+ InGroup<CXXPre26Compat>,
+ DefaultIgnore;
def ext_pp_extra_tokens_at_eol : ExtWarn<
"extra tokens at end of #%0 directive">, InGroup<ExtraTokens>;
@@ -483,7 +499,13 @@ def ext_pp_gnu_line_directive : Extension<
def err_pp_invalid_directive : Error<
"invalid preprocessing directive%select{|, did you mean '#%1'?}0">;
def warn_pp_invalid_directive : Warning<
- err_pp_invalid_directive.Summary>, InGroup<DiagGroup<"unknown-directives">>;
+ err_pp_invalid_directive.Summary>,
+ InGroup<UnsupportedDirective>;
+def warn_pp_unknown_parameter_ignored : Warning<
+ "unknown%select{ | embed}0 preprocessor parameter '%1' ignored">,
+ InGroup<UnknownDirectiveParameters>;
+def err_pp_unsupported_directive : Error<
+ "unsupported%select{ | embed}0 directive: %1">;
def err_pp_directive_required : Error<
"%0 must be used within a preprocessing directive">;
def err_pp_file_not_found : Error<"'%0' file not found">, DefaultFatal;
diff --git a/clang/include/clang/Basic/FileManager.h b/clang/include/clang/Basic/FileManager.h
index 56cb093dd8c376f..c757f8775b425e9 100644
--- a/clang/include/clang/Basic/FileManager.h
+++ b/clang/include/clang/Basic/FileManager.h
@@ -276,11 +276,13 @@ 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,
+ std::optional<int64_t> MaybeLimit = std::nullopt);
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(StringRef Filename, bool isVolatile = false,
- bool RequiresNullTerminator = true) {
- return getBufferForFileImpl(Filename, /*FileSize=*/-1, isVolatile,
+ bool RequiresNullTerminator = true,
+ std::optional<int64_t> MaybeLimit = std::nullopt) {
+ return getBufferForFileImpl(Filename, /*FileSize=*/(MaybeLimit ? *MaybeLimit : -1), isVolatile,
RequiresNullTerminator);
}
diff --git a/clang/include/clang/Basic/StmtNodes.td b/clang/include/clang/Basic/StmtNodes.td
index cec301dfca2817b..e3be997dd1c86e0 100644
--- a/clang/include/clang/Basic/StmtNodes.td
+++ b/clang/include/clang/Basic/StmtNodes.td
@@ -203,6 +203,7 @@ def OpaqueValueExpr : StmtNode<Expr>;
def TypoExpr : StmtNode<Expr>;
def RecoveryExpr : StmtNode<Expr>;
def BuiltinBitCastExpr : StmtNode<ExplicitCastExpr>;
+def PPEmbedExpr : StmtNode<Expr>;
// Microsoft Extensions.
def MSPropertyRefExpr : StmtNode<Expr>;
diff --git a/clang/include/clang/Basic/TokenKinds.def b/clang/include/clang/Basic/TokenKinds.def
index 94db56a9fd5d78c..167bd614efe7bd9 100644
--- a/clang/include/clang/Basic/TokenKinds.def
+++ b/clang/include/clang/Basic/TokenKinds.def
@@ -126,6 +126,9 @@ PPKEYWORD(error)
// C99 6.10.6 - Pragma Directive.
PPKEYWORD(pragma)
+// C23 & C++26 #embed
+PPKEYWORD(embed)
+
// GNU Extensions.
PPKEYWORD(import)
PPKEYWORD(include_next)
@@ -751,6 +754,7 @@ ALIAS("__char32_t" , char32_t , KEYCXX)
KEYWORD(__builtin_bit_cast , KEYALL)
KEYWORD(__builtin_available , KEYALL)
KEYWORD(__builtin_sycl_unique_stable_name, KEYSYCL)
+KEYWORD(__builtin_pp_embed , KEYALL)
// Keywords defined by Attr.td.
#ifndef KEYWORD_ATTRIBUTE
@@ -986,6 +990,7 @@ ANNOTATION(repl_input_end)
#undef CXX11_KEYWORD
#undef KEYWORD
#undef PUNCTUATOR
+#undef BUILTINOK
#undef TOK
#undef C99_KEYWORD
#undef C23_KEYWORD
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 5415b18d3f406df..bfc4b15d5411cde 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -114,6 +114,11 @@ def IncludePath_Group : OptionGroup<"<I/i group>">, Group<Preprocessor_Group>,
DocBrief<[{
Flags controlling how ``#include``\s are resolved to files.}]>;
+def EmbedPath_Group : OptionGroup<"<Embed group>">, Group<Preprocessor_Group>,
+ DocName<"Embed path management">,
+ DocBrief<[{
+Flags controlling how ``#embed``\s and similar are resolved to files.}]>;
+
def I_Group : OptionGroup<"<I group>">, Group<IncludePath_Group>, DocFlatten;
def i_Group : OptionGroup<"<i group>">, Group<IncludePath_Group>, DocFlatten;
def clang_i_Group : OptionGroup<"<clang i group>">, Group<i_Group>, DocFlatten;
@@ -816,6 +821,14 @@ will be ignored}]>;
def L : JoinedOrSeparate<["-"], "L">, Flags<[RenderJoined]>, Group<Link_Group>,
Visibility<[ClangOption, FlangOption]>,
MetaVarName<"<dir>">, HelpText<"Add directory to library search path">;
+def embed_dir : JoinedOrSeparate<["-"], "embed-dir">,
+ Flags<[RenderJoined]>, Group<EmbedPath_Group>,
+ Visibility<[ClangOption, CC1Option, CC1AsOption, FlangOption, FC1Option]>,
+ MetaVarName<"<dir>">, HelpText<"Add directory to embed search path">;
+def embed_dir_EQ : JoinedOrSeparate<["-"], "embed-dir=">,
+ Flags<[RenderJoined]>, Group<EmbedPath_Group>,
+ Visibility<[ClangOption, CC1Option, CC1AsOption, FlangOption, FC1Option]>,
+ MetaVarName<"<dir>">, HelpText<"Add directory to embed search path">;
def MD : Flag<["-"], "MD">, Group<M_Group>,
HelpText<"Write a depfile containing user and system headers">;
def MMD : Flag<["-"], "MMD">, Group<M_Group>,
@@ -1353,6 +1366,9 @@ def dD : Flag<["-"], "dD">, Group<d_Group>, Visibility<[ClangOption, CC1Option]>
def dI : Flag<["-"], "dI">, Group<d_Group>, Visibility<[ClangOption, CC1Option]>,
HelpText<"Print include directives in -E mode in addition to normal output">,
MarshallingInfoFlag<PreprocessorOutputOpts<"ShowIncludeDirectives">>;
+def dE : Flag<["-"], "dE">, Group<d_Group>, Visibility<[ClangOption, CC1Option]>,
+ HelpText<"Print embed directives in -E mode in addition to normal output">,
+ MarshallingInfoFlag<PreprocessorOutputOpts<"ShowEmbedDirectives">>;
def dM : Flag<["-"], "dM">, Group<d_Group>, Visibility<[ClangOption, CC1Option]>,
HelpText<"Print macro definitions in -E mode instead of normal output">;
def dead__strip : Flag<["-"], "dead_strip">;
diff --git a/clang/include/clang/Frontend/PreprocessorOutputOptions.h b/clang/include/clang/Frontend/PreprocessorOutputOptions.h
index db2ec9f2ae20698..3e36db3f8ce46ea 100644
--- a/clang/include/clang/Frontend/PreprocessorOutputOptions.h
+++ b/clang/include/clang/Frontend/PreprocessorOutputOptions.h
@@ -22,6 +22,7 @@ class PreprocessorOutputOptions {
unsigned ShowMacroComments : 1; ///< Show comments, even in macros.
unsigned ShowMacros : 1; ///< Print macro definitions.
unsigned ShowIncludeDirectives : 1; ///< Print includes, imports etc. within preprocessed output.
+ unsigned ShowEmbedDirectives : 1; ///< Print embeds, etc. within preprocessed output.
unsigned RewriteIncludes : 1; ///< Preprocess include directives only.
unsigned RewriteImports : 1; ///< Include contents of transitively-imported modules.
unsigned MinimizeWhitespace : 1; ///< Ignore whitespace from input.
@@ -37,6 +38,7 @@ class PreprocessorOutputOptions {
ShowMacroComments = 0;
ShowMacros = 0;
ShowIncludeDirectives = 0;
+ ShowEmbedDirectives = 0;
RewriteIncludes = 0;
RewriteImports = 0;
MinimizeWhitespace = 0;
diff --git a/clang/include/clang/Lex/PPCallbacks.h b/clang/include/clang/Lex/PPCallbacks.h
index 94f96cf9c512541..7028c81dbc84aac 100644
--- a/clang/include/clang/Lex/PPCallbacks.h
+++ b/clang/include/clang/Lex/PPCallbacks.h
@@ -22,11 +22,11 @@
#include "llvm/ADT/StringRef.h"
namespace clang {
- class Token;
- class IdentifierInfo;
- class MacroDefinition;
- class MacroDirective;
- class MacroArgs;
+class Token;
+class IdentifierInfo;
+class MacroDefinition;
+class MacroDirective;
+class MacroArgs;
/// This interface provides a way to observe the actions of the
/// preprocessor as it does its thing.
@@ -36,9 +36,7 @@ class PPCallbacks {
public:
virtual ~PPCallbacks();
- enum FileChangeReason {
- EnterFile, ExitFile, SystemHeaderPragma, RenameFile
- };
+ enum FileChangeReason { EnterFile, ExitFile, SystemHeaderPragma, RenameFile };
/// Callback invoked whenever a source file is entered or exited.
///
@@ -47,8 +45,7 @@ class PPCallbacks {
/// the file before the new one entered for \p Reason EnterFile.
virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
SrcMgr::CharacteristicKind FileType,
- FileID PrevFID = FileID()) {
- }
+ FileID PrevFID = FileID()) {}
enum class LexedFileChangeReason { EnterFile, ExitFile };
@@ -83,6 +80,47 @@ class PPCallbacks {
const Token &FilenameTok,
SrcMgr::CharacteristicKind FileType) {}
+ /// Callback invoked whenever the preprocessor cannot find a file for an
+ /// embed directive.
+ ///
+ /// \param FileName The name of the file being included, as written in the
+ /// source code.
+ ///
+ /// \returns true to indicate that the preprocessor should skip this file
+ /// and not issue any diagnostic.
+ virtual bool EmbedFileNotFound(StringRef FileName) { return false; }
+
+ /// Callback invoked whenever an embed directive has been processed,
+ /// regardless of whether the embed will actually find a file.
+ ///
+ /// \param HashLoc The location of the '#' that starts the embed directive.
+ ///
+ /// \param FileName The name of the file being included, as written in the
+ /// source code.
+ ///
+ /// \param IsAngled Whether the file name was enclosed in angle brackets;
+ /// otherwise, it was enclosed in quotes.
+ ///
+ /// \param FilenameRange The character range of the quotes or angle brackets
+ /// for the written file name.
+ ///
+ /// \param ParametersRange The character range of the embed parameters. An
+ /// empty range if there were no parameters.
+ ///
+ /// \param File The actual file that may be included by this embed directive.
+ ///
+ /// \param SearchPath Contains the search path which was used to find the file
+ /// in the file system. If the file was found via an absolute path,
+ /// SearchPath will be empty.
+ ///
+ /// \param RelativePath The path relative to SearchPath, at which the resource
+ /// file was found. This is equal to FileName.
+ virtual void EmbedDirective(SourceLocation HashLoc, StringRef FileName,
+ bool IsAngled, CharSourceRange FilenameRange,
+ CharSourceRange ParametersRange,
+ OptionalFileEntryRef File, StringRef SearchPath,
+ StringRef RelativePath) {}
+
/// Callback invoked whenever the preprocessor cannot find a file for an
/// inclusion directive.
///
@@ -151,7 +189,7 @@ class PPCallbacks {
/// \param ForPragma If entering from pragma directive.
///
virtual void EnteredSubmodule(Module *M, SourceLocation ImportLoc,
- bool ForPragma) { }
+ bool ForPragma) {}
/// Callback invoked whenever a submodule was left.
///
@@ -162,7 +200,7 @@ class PPCallbacks {
/// \param ForPragma If entering from pragma directive.
///
virtual void LeftSubmodule(Module *M, SourceLocation ImportLoc,
- bool ForPragma) { }
+ bool ForPragma) {}
/// Callback invoked whenever there was an explicit module-import
/// syntax.
@@ -174,49 +212,40 @@ class PPCallbacks {
///
/// \param Imported The imported module; can be null if importing failed.
///
- virtual void moduleImport(SourceLocation ImportLoc,
- ModuleIdPath Path,
- const Module *Imported) {
- }
+ virtual void moduleImport(SourceLocation ImportLoc, ModuleIdPath Path,
+ const Module *Imported) {}
/// Callback invoked when the end of the main file is reached.
///
/// No subsequent callbacks will be made.
- virtual void EndOfMainFile() {
- }
+ virtual void EndOfMainFile() {}
/// Callback invoked when a \#ident or \#sccs directive is read.
/// \param Loc The location of the directive.
/// \param str The text of the directive.
///
- virtual void Ident(SourceLocation Loc, StringRef str) {
- }
+ virtual void Ident(SourceLocation Loc, StringRef str) {}
/// Callback invoked when start reading any pragma directive.
virtual void PragmaDirective(SourceLocation Loc,
- PragmaIntroducerKind Introducer) {
- }
+ PragmaIntroducerKind Introducer) {}
/// Callback invoked when a \#p...
[truncated]
|
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
|
FWIW, I spoke offline with the original author of the PR and he said that he's fine with me picking up the changes and carrying the review forward. Because I don't know of any better way to commandeer a patch in GitHub, I'll probably grab the changes, get them into my own fork, and then recreate the PR to get the review started. Whenever we get ready to land the PR, @ThePhD will be credited as a co-author. |
As a maintainer, you can push into this branch (unless @ThePhD unchecked the default setting when creating the PR), including forcefully. For example (you could also use the github CLI, but I'm using vanilla git to demo): |
Amazing! I had started to think about looking into getting this implemented recently, so it's really nice to see an implementation uploaded now!
I'm very sorry to hear that, but thank you for the contribution regardless! |
So just to clarify, we should wait till you post a follow-up review before commenting, to avoid fragmenting the discussion. |
I had reached out to @ThePhD with an offer to help on this before they opened this PR, and I now have push access to their fork, which means I could change the state of this PR. To be clear, I cannot offer to defend the content (semantically) in the face of review, but - if desired - I'd be happy to help with some more routine operations like rebasing, formatting, or chopping off pieces into separate PRs (all while keeping @ThePhD's authorship, of course). |
Oh, that's excellent! @ThePhD also gave me push access to his repo. If we're going to tag-team efforts on this and we both have access, it probably makes sense to just leave it in his repo and work from there. If he finds the notifications too distracting, we can always move the work elsewhere at that point. @h-vetinari -- would you mind doing some initial cleanup on the patch for things like rebasing, removing spurious formatting changes, naming, and the likes? I have WG14 meetings coming up next week (they should hopefully go quickly though), so it is likely going to be ~a week before I have the chance to work on this more heavily.
Given the above, I'd say we can keep the review going here. |
I'll try to do that! |
…+26. 🛠 [Frontend] Ensure commas inserted by #embed are properly serialized to output
|
OK, I've got a first rebase going. However, because iterating on a diff with 1000s of lines is extremely hard to review and bound to lead to mistakes and iterations (making it harder still to follow what's going on), I've tried to follow a more structured approach. Basically, I've pushed tags for intermediate milestones during the rebase to my fork, and am documenting below what I've done. That should make it easier to:
I've used a simple tag scheme The table is probably busted visually on mobile (sorry...), but I hope it reads alright on a desktop. Where used, equality (
Since the rebase from v3 to v4 went cleanly, I haven't run the compilation tests. I will push Footnotes
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⚡ [Lex] Better reservations for improved performance/memory usage. 🛠 [Lex, Frontend] Remove comma hardcoding since we are servicing a full file apply suggestions from git-clang-format
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changed the title
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JeanHeyd wrote up a blog post about this implementation, which is probably helpful as background material for any prospective reviewers. :) |
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@AaronBallman, hope the WG14 meeting went well? I've essentially done what I planned to do here, so I was wondering if you're ready to take it from here? I can try to incorporate the review feedback myself, but it's quite likely I'd make a mess of it (not familiar with the clang code base at all). 😅 |
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@vitalybuka @rorth thanks for the reports. |
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Note, the version of clang with the above changes I've tried still crashes on the embed-1.c test I'm writing for GCC test coverage, has some I believe incorrect parsing issues and if all the problematic stuff is commented out, fails at runtime |
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Also wonder (for GCC the implementation is doing that too right now) if #embed on non-existent file needs to be a fatal error, for missing #include that is certainly the right thing, but perhaps #embed on non-existent/non-readable etc. file could be just treated as empty file after normal errors. |
#if __has_embed("")
#endif
#if __has_embed(<>)
#endif
#embed ""
#embed <>crashes as well in all 4 cases, but this is different from the earlier crash, incorrect parsing errors or runtime failures. |
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Also, _Static_assert(sizeof(
#embed <single_byte.txt>
) ==
sizeof(unsigned char)
, ""
);looks wrong to me. It also fails with clang -save-temps. I'd think sizeof ( |
Huh, well that's interesting. I thought there was a standard requirement that the values be in a type matching that of the embed resource element width, so because our element width is The choice here matters for things like @ThePhD -- do you have any input here as the feature author? |
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The preprocessor has no notion of types and there are no integer literal suffixes for unsigned char constants, so if the intent was to make the constants have unsigned char, the preprocessor (unless doing magic, including -E preprocessing) would need to replace |
Yeah, at one point I was doing exactly that. :-D But I think we should probably go with straight integer literal values instead of casted integer constant expressions; we can add a custom embed parameter if we want to give users more control over the type of the elements. So I think the correct fix here is to change: to use |
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https://godbolt.org/z/WhjhPrYns |
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Thank you for all the excellent help @jakubjelinek, this has been really great feedback! @Fznamznon -- I think the next steps for this should be to get the patch back to the point of passing CI without leaks, land the changes knowing there are still some issues to be worked out (as listed here and in #95222), and then start tackling those issues once the changes have landed. |
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Hi @AaronBallman! As Jakub pointed out, the casting bit was something I did to give a consistent type to the literals. I dropped this wording for C in the specification but kept it in for C++ because they have more cases where they care deeply about what comes out (initializer lists, template argument deduction, constructors/conversions, etc.). For the implementation I would recommend not casting for C as that is what the spec says right now. I can change that with a follow up paper I plan to do for #embed anyways for the C wording. This is not much of a material problem in C because, thankfully, there is nothing that can manifest this as a real problem, only test suite issues on precise semantics. |
Chiming in here, embed on a non-existent file should be an error. This is the intent. Because we provide a way to check if the file exists with |
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I'm not arguing about the error, just about whether it is a fatal error (in the sense that compilation stops immediately and no errors later on in the file are reported) vs. just a normal error (where it would diagnose it, then pretend the file is empty and so copy over if_empty tokens if any) and continue preprocessing and compilation, obviously with a non-zero error code from the compilation at the end. Yes, some extra errors might be reported because e.g. the source code syntactically wouldn't be able to deal with empty file, but perhaps in the common case it could help to users to find more issues in the same compilation. |
This makes sense. My initial thought was that a missing embed-file would be like a missing header. But a missing header is treated as fatal because the lack of declarations provided by a header would lead to cascading errors (i.e., noise) against subsequent code that uses those declarations. In contrast, it's not clear (to me) that the well-formedness of code following an ill-formed Having said that... Does the question of error category need to be resolved before |
I think my opinion on this depends on what this actually means; forgive me for not understanding your distinction here. The idea that this is a warning that will not stop compilation and my code which handles and empty file but was not expecting one just finishes building is bad. If you're referring to architecture that differentiates between "error that stops now" and "error that stops eventually", then sure. If this is "a casual warning versus an actual error", then please don't do this. |
Pretty sure this is just a question of whether the compiler should:
It makes zero difference at this point I think. It's an error either way since builds always fail, so the precise length of the resulting diagnostic output can be freely changed on a whim post-merge, as and when the compiler developers change their mind about how helpful said diagnostics are. |
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My original thinking was that this should behave like a missing where the follow-on error will be about invalid initialization of a constexpr variable if So I think I'd be fine making it a non-fatal error (but still an error; a warning would be problematic). |
I don't think it's acceptable for C and C++ to have different behavior here: where Given that the conceptual model for IMO, if users need fine-grained control over the element type, that should be handled via an explicitly written embed parameter; the preprocessor should remain as generally type agnostic as it is today. |
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I agree. If you want unsigned char constants, start with standardizing some integer literal suffix like UC for unsigned char (or whatever else), then add a new #embed parameter which allows e.g. to supply a suffix for all the constant literals, |
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I'll bring this up when this paper is discussed, probably at end-of-year or start-of-next-year, whichever meeting I can attend. Though, FWIW, this was an explicit user request at-the-time, given But sure; for C++ implement it as naked literals and use the force of implementation as a reason to help me justify the way you want it when this comes up for discussion in the C++ Committee, as I'm sure it inevitably will. |
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Whether void* f() __attribute__((availability(macos,introduced=
#embed "digit.txt"
)));and struct S {
virtual void f() =
#embed "zero.txt"
;
};And that needs to behave similarly in C and C++, such that if the say wording says that embed produces integer literal tokens (with no suffixes) (making the above nonsense well formed), C++ needs to follow suite |
Can't you attend it just remotely next week? Or does the paper author need to be physically present in CWG for the discussion of the paper? |
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OT, more complete analysis of the bugs on the clang side (at least IMHO) and implementation differences between this branch and GCC patch and the branch on godbolt are in the description of my gcc patch: |
The following patch implements the C23 N3017 "#embed - a scannable,
tooling-friendly binary resource inclusion mechanism" paper.
The implementation is intentionally dumb, in that it doesn't significantly
speed up compilation of larger initializers and doesn't make it possible
to use huge #embeds (like several gigabytes large, that is compile time
and memory still infeasible).
There are 2 reasons for this. One is that I think like it is implemented
now in the patch is how we should use it for the smaller #embed sizes,
dunno with which boundary, whether 32 bytes or 64 or something like that,
certainly handling the single byte cases which is something that can appear
anywhere in the source where constant integer literal can appear is
desirable and I think for a few bytes it isn't worth it to come up with
something smarter and users would like to e.g. see it in -E readably as
well (perhaps the slow vs. fast boundary should be determined by command
line option). And the other one is to be able to more easily find
regressions in behavior caused by the optimizations, so we have something
to get back in git to compare against.
I'm definitely willing to work on the optimizations (likely introduce a new
CPP_* token type to refer to a range of libcpp owned memory (start + size)
and similarly some tree which can do the same, and can be at any time e.g.
split into 2 subparts + say INTEGER_CST in between if needed say for
const unsigned char d[] = {
#embed "2GB.dat" prefix (0, 0, ) suffix (, [0x40000000] = 42)
}; still without having to copy around huge amounts of data; STRING_CST
owns the memory it points to and can be only 2GB in size), but would
like to do that incrementally.
And would like to first include some extensions also not included in
this patch, like gnu::offset (off) parameter to allow to skip certain
constant amount of bytes at the start of the files, plus
gnu::base64 ("base64_encoded_data") parameter to add something which can
store more efficiently large amounts of the #embed data in preprocessed
source.
I've been cross-checking all the tests also against the LLVM implementation
llvm/llvm-project#68620
which has been for a few hours even committed to LLVM trunk but reverted
afterwards. LLVM now has the support committed and I admit I haven't
rechecked whether the behavior on the below mentioned spots have been fixed
in it already or not yet.
The patch uses --embed-dir= option that clang plans to add above and doesn't
use other variants on the search directories yet, plus there are no
default directories at least for the time being where to search for embed
files. So, #embed "..." works if it is found in the same directory (or
relative to the current file's directory) and #embed "/..." or #embed </...>
work always, but relative #embed <...> doesn't unless at least one
--embed-dir= is specified. There is no reason to differentiate between
system and non-system directories, so we don't need -isystem like
counterpart, perhaps -iquote like counterpart could be useful in the future,
dunno what else. It has --embed-directory=dir and --embed-directory dir
as aliases.
There are some differences beyond clang ICEs, so I'd like to point them out
to make sure there is agreement on the choices in the patch. They are also
mentioned in the comments of the llvm pull request.
The most important is that the GCC patch (as well as the original thephd.dev
LLVM branch on godbolt) expands #embed (or acts as if it is expanded) into
a mere sequence of numbers like 123,2,35,26 rather then what clang
effectively treats as (unsigned char)123,(unsigned char)2,(unsigned
char)35,(unsigned char)26 but only does that when using integrated
preprocessor, not when using -save-temps where it acts as GCC.
JeanHeyd as the original author agrees that is how it is currently worded in
C23.
Another difference (not tested in the testsuite, not sure how to check for
effective target /dev/urandom nor am sure it is desirable to check that
during testsuite) is how to treat character devices, named pipes etc.
(block devices are errored on). The original paper uses /dev/urandom
in various examples and seems to assume that unlike regular files the
devices aren't really cached, so
#embed </dev/urandom> limit(1) prefix(int a = ) suffix(;)
#embed </dev/urandom> limit(1) prefix(int b = ) suffix(;)
usually results in a != b. That is what the godbolt thephd.dev branch
implements too and what this patch does as well, but clang actually seems
to just go from st.st_size == 0, ergo it must be zero-sized resource and
so just copies over if_empty if present. It is really questionable
what to do about the character devices/named pipes with __has_embed, for
regular files the patch doesn't read anything from them, relies on
st.st_size + limit for whether it is empty or non-empty. But I don't know
of a way to check if read on say a character device would read anything
or not (the </dev/null> limit (1) vs. </dev/zero> limit (1) cases), and
if we read something, that would be better cached for later because
#embed later if it reads again could read no further data even when it
first read something. So, the patch currently for __has_embed just
always returns 2 on the non-regular files, like the thephd.dev
branch does as well and like the clang pull request as well.
A question is also what to do for gnu::offset on the non-regular files
even for #embed, those aren't seekable and do we want to just read and throw
away the offset bytes each time we see it used?
clang also chokes on the
#if __has_embed (__FILE__ __limit__ (1) __prefix__ () suffix (1 / 0) \
__if_empty__ ((({{[0[0{0{0(0(0)1)1}1}]]}})))) != __STDC_EMBED_FOUND__
#error "__has_embed fail"
#endif
in embed-1.c, but thephd.dev branch accepts it and I don't see why
it shouldn't, (({{[0[0{0{0(0(0)1)1}1}]]}}))) is a balanced token
sequence and the file isn't empty, so it should just be parsed and
discarded.
clang also IMHO mishandles
const unsigned char w[] = {
#embed __FILE__ prefix([0] = 42, [15] =) limit(32)
};
but again only without -save-temps, seems like it
treats it as
[0] = 42, [15] = (99,111,110,115,116,32,117,110,115,105,103,110,101,100,
32,99,104,97,114,32,119,91,93,32,61,32,123,10,35,101,109,98)
rather than
[0] = 42, [15] = 99,111,110,115,116,32,117,110,115,105,103,110,101,100,
32,99,104,97,114,32,119,91,93,32,61,32,123,10,35,101,109,98
and warns on it for -Wunused-value and just compiles it as
[0] = 42, [15] = 98
And also
void foo (int, int, int, int);
void bar (void) { foo (
#embed __FILE__ limit (4) prefix (172 + ) suffix (+ 2)
); }
is treated as
172 + (118, 111, 105, 100) + 2
rather than
172 + 118, 111, 105, 100 + 2
which clang -save-temps or GCC treats it like, so results
in just one argument passed rather than 4.
if (!strstr ((const char *) magna_carta, "imprisonétur")) abort ();
in the testcase fails as well, but in that case calling it in gdb succeeds:
p ((char *(*)(char *, char *))__strstr_sse2) (magna_carta, "imprisonétur")
$2 = 0x555555558d3c <magna_carta+11564> "imprisonétur aut disseisiátur"...
so I guess they are just trying to constant evaluate strstr and do it
incorrectly.
They started with making the optimizations together in the initial patch
set, so they don't have the luxury to compare if it is just because of
the optimization they are trying to do or because that is how the
feature works for them. At least unless they use -save-temps for now.
There is also different behavior between clang and gcc on -M or other
dependency generating options. Seems clang includes the __has_embed
searched files in dependencies, while my patch doesn't. But so does
clang for __has_include and GCC doesn't. Emitting a hard dependency
on some header just because there was __has_include/__has_embed for it
seems wrong to me, because (at least when properly written) the source
likely doesn't mind if the file is missing, it will do something else,
so a hard error from make because of it doesn't seem right. Does
make have some weaker dependencies, such that if some file can be remade
it is but if it doesn't exist, it isn't fatal?
I wonder whether #embed <non-existent-file> really needs to be fatal
or whether we could simply after diagnosing it pretend the file exists
and is empty. For #include I think fatal errors make tons of sense,
but perhaps for #embed which is more localized we'd get better error
reporting if we didn't bail out immediately. Note, both GCC and clang
currently treat those as fatal errors.
clang also added -dE option which with -E instead of preprocessing
the #embed directives keeps them as is, but the preprocessed source
then isn't self-contained. That option looks more harmful than useful to
me.
Also, it isn't clear to me from C23 whether it is possible to have
__has_include/__has_c_attribute/__has_embed expressions inside of
the limit #embed/__has_embed argument.
6.10.3.2/2 says that defined should not appear there (and the patch
diagnoses it and testsuite tests), but for __has_include/__has_embed
etc. 6.10.1/11 says:
"The identifiers __has_include, __has_embed, and __has_c_attribute
shall not appear in any context not mentioned in this subclause."
If that subclause in that case means 6.10.1, then it presumably shouldn't
appear in #embed in 6.10.3, but __has_embed is in 6.10.1...
But 6.10.3.2/3 says that it should be parsed according to the 6.10.1
rules. Haven't included tests like
#if __has_embed (__FILE__ limit (__has_embed (__FILE__ limit (1))))
or
#embed __FILE__ limit (__has_include (__FILE__))
into the testsuite because of the doubts but I think the patch should
handle those right now.
The reason I've used Magna Carta text in some of the testcases is that
I hope it shouldn't be copyrighted after the centuries and I'd strongly
prefer not to have binary blobs in git after the xz backdoor lesson
and wanted something larger which doesn't change all the time.
Oh, BTW, I see in C23 draft 6.10.3.2 in Example 4
if (f_source == NULL);
return 1;
(note the spurious semicolon after closing paren), has that been fixed
already?
Like the thephd.dev and clang implementations, the patch always macro
expands the whole #embed and __has_embed directives except for the
embed keyword. That is most likely not what C23 says, my limited
understanding right now is that in #embed one needs to parse the whole
directive line with macro expansion disabled and check if it satisfies the
grammar, if not, the whole directive is macro expanded, if yes, only
the limit parameter argument is macro expanded and the prefix/suffix/if_empty
arguments are maybe macro expanded when actually used (and not at all if
unused). And I think __has_embed macro expansion has conflicting rules.
2024-09-12 Jakub Jelinek <jakub@redhat.com>
PR c/105863
libcpp/
* include/cpplib.h: Implement C23 N3017 #embed - a scannable,
tooling-friendly binary resource inclusion mechanism paper.
(struct cpp_options): Add embed member.
(enum cpp_builtin_type): Add BT_HAS_EMBED.
(cpp_set_include_chains): Add another cpp_dir * argument to
the declaration.
* internal.h (enum include_type): Add IT_EMBED.
(struct cpp_reader): Add embed_include member.
(struct cpp_embed_params_tokens): New type.
(struct cpp_embed_params): New type.
(_cpp_get_token_no_padding): Declare.
(enum _cpp_find_file_kind): Add _cpp_FFK_EMBED and _cpp_FFK_HAS_EMBED.
(_cpp_stack_embed): Declare.
(_cpp_parse_expr): Change return type to cpp_num_part instead of
bool, change second argument from bool to const char * and add third
argument.
(_cpp_parse_embed_params): Declare.
* directives.cc (DIRECTIVE_TABLE): Add embed entry.
(end_directive): Don't call skip_rest_of_line for T_EMBED directive.
(_cpp_handle_directive): Return 2 rather than 1 for T_EMBED in
directives-only mode.
(parse_include): Don't Call check_eol for T_EMBED directive.
(skip_balanced_token_seq): New function.
(EMBED_PARAMS): Define.
(enum embed_param_kind): New type.
(embed_params): New variable.
(_cpp_parse_embed_params): New function.
(do_embed): New function.
(do_if): Adjust _cpp_parse_expr caller.
(do_elif): Likewise.
* expr.cc (parse_defined): Diagnose defined in #embed or __has_embed
parameters.
(_cpp_parse_expr): Change return type to cpp_num_part instead of
bool, change second argument from bool to const char * and add third
argument. Adjust function comment. For #embed/__has_embed parameters
add an artificial CPP_OPEN_PAREN. Use the second argument DIR
directly instead of string literals conditional on IS_IF.
For #embed/__has_embed parameter, stop on reaching CPP_CLOSE_PAREN
matching the artificial one. Diagnose negative or too large embed
parameter operands.
(num_binary_op): Use #embed instead of #if for diagnostics if inside
#embed/__has_embed parameter.
(num_div_op): Likewise.
* files.cc (struct _cpp_file): Add limit member and embed bitfield.
(search_cache): Add IS_EMBED argument, formatting fix. Skip over
files with different file->embed from the argument.
(find_file_in_dir): Don't call pch_open_file if file->embed.
(_cpp_find_file): Handle _cpp_FFK_EMBED and _cpp_FFK_HAS_EMBED.
(read_file_guts): Formatting fix.
(has_unique_contents): Ignore file->embed files.
(search_path_head): Handle IT_EMBED type.
(_cpp_stack_embed): New function.
(_cpp_get_file_stat): Formatting fix.
(cpp_set_include_chains): Add embed argument, save it to
pfile->embed_include and compute lens for the chain.
* init.cc (struct lang_flags): Add embed member.
(lang_defaults): Add embed initializers.
(cpp_set_lang): Initialize CPP_OPTION (pfile, embed).
(builtin_array): Add __has_embed entry.
(cpp_init_builtins): Predefine __STDC_EMBED_NOT_FOUND__,
__STDC_EMBED_FOUND__ and __STDC_EMBED_EMPTY__.
* lex.cc (cpp_directive_only_process): Handle #embed.
* macro.cc (cpp_get_token_no_padding): Rename to ...
(_cpp_get_token_no_padding): ... this. No longer static.
(builtin_has_include_1): New function.
(builtin_has_include): Use it. Use _cpp_get_token_no_padding
instead of cpp_get_token_no_padding.
(builtin_has_embed): New function.
(_cpp_builtin_macro_text): Handle BT_HAS_EMBED.
gcc/
* doc/cppdiropts.texi (--embed-dir=): Document.
* doc/cpp.texi (Binary Resource Inclusion): New chapter.
(__has_embed): Document.
* doc/invoke.texi (Directory Options): Mention --embed-dir=.
* gcc.cc (cpp_unique_options): Add %{-embed*}.
* genmatch.cc (main): Adjust cpp_set_include_chains caller.
* incpath.h (enum incpath_kind): Add INC_EMBED.
* incpath.cc (merge_include_chains): Handle INC_EMBED.
(register_include_chains): Adjust cpp_set_include_chains caller.
gcc/c-family/
* c.opt (-embed-dir=): New option.
(-embed-directory): New alias.
(-embed-directory=): New alias.
* c-opts.cc (c_common_handle_option): Handle OPT__embed_dir_.
gcc/testsuite/
* c-c++-common/cpp/embed-1.c: New test.
* c-c++-common/cpp/embed-2.c: New test.
* c-c++-common/cpp/embed-3.c: New test.
* c-c++-common/cpp/embed-4.c: New test.
* c-c++-common/cpp/embed-5.c: New test.
* c-c++-common/cpp/embed-6.c: New test.
* c-c++-common/cpp/embed-7.c: New test.
* c-c++-common/cpp/embed-8.c: New test.
* c-c++-common/cpp/embed-9.c: New test.
* c-c++-common/cpp/embed-10.c: New test.
* c-c++-common/cpp/embed-11.c: New test.
* c-c++-common/cpp/embed-12.c: New test.
* c-c++-common/cpp/embed-13.c: New test.
* c-c++-common/cpp/embed-14.c: New test.
* c-c++-common/cpp/embed-25.c: New test.
* c-c++-common/cpp/embed-26.c: New test.
* c-c++-common/cpp/embed-dir/embed-1.inc: New test.
* c-c++-common/cpp/embed-dir/embed-3.c: New test.
* c-c++-common/cpp/embed-dir/embed-4.c: New test.
* c-c++-common/cpp/embed-dir/magna-carta.txt: New test.
* gcc.dg/cpp/embed-1.c: New test.
* gcc.dg/cpp/embed-2.c: New test.
* gcc.dg/cpp/embed-3.c: New test.
* gcc.dg/cpp/embed-4.c: New test.
* g++.dg/cpp/embed-1.C: New test.
* g++.dg/cpp/embed-2.C: New test.
* g++.dg/cpp/embed-3.C: New test.
This pull request implements the entirety of the now-accepted N3017 - Preprocessor Embed and its sister C++ paper p1967. It implements everything in the specification, and includes an implementation that drastically improves the time it takes to embed data in specific scenarios (the initialization of character type arrays). The mechanisms used to do this are used under the "as-if" rule, and in general when the system cannot detect it is initializing an array object in a variable declaration, will simply expand the list out to a sequence of numbers.
There are likely places where the
__builtin_pp_embedintrinsic fails to compile properly and triggers ICEs. However, we have covered what we feel are the vast majority of cases where users would want or need the speedup.Images are a dry run of a recently built clang and LLVM on Release mode (not RelWithDebInfo) on Windows, under the following properties:
OS Name: Microsoft Windows 10 Pro
Version: 10.0.19045 Build 19045
System Type: x64-based PC
Processor: AMD Ryzen 9 5950X 16-Core Processor, 3401 Mhz, 16 Core(s), 32 Logical Processor(s)
Installed Physical Memory (RAM): 32.0 GB
Total Physical Memory: 31.9 GB
Total Virtual Memory: 36.7 GB
All of the added tests pass under the above machine properties.
I have no intention of following up on this PR. I am too tired to carry it to fruition. Pick this apart, take from it what you want, or reimplement it entirely. (I will be unsubscribing from this immediately after posting.)
Good luck ✌!