Commit a9dd8d75431357a59238da3fd949aa1f11eead84 | zig

author	Evan Haas <evan@lagerdata.com> 2021-06-01 20:00:46-07:00
committer	Veikka Tuominen <git@vexu.eu> 2021-06-02 09:12:45+03:00
log	a9dd8d75431357a59238da3fd949aa1f11eead84
tree	d9074122fe12aa0a7ec2855216418743ea36b1f8
parent	c6a0a4e7282d746ebf2b54df16161c5993ea5aa8

translate-c: Fix performance hazard in transPreprocessorEntities

Fixes O(N^2) behavior of `transPreprocessorEntities` due to repeated calls to
`mem.len`

Closes #8959

4 files changed, 20 insertions(+), 1 deletions(-)

src/clang.zig+7

...	@@ -607,6 +607,13 @@ pub const IntegerLiteral = opaque {	...	@@ -607,6 +607,13 @@ pub const IntegerLiteral = opaque {
607	extern fn ZigClangIntegerLiteral_isZero(const IntegerLiteral, bool, *const ASTContext) bool;	607	extern fn ZigClangIntegerLiteral_isZero(const IntegerLiteral, bool, *const ASTContext) bool;
608	};	608	};
609		609
		610	/// This is just used as a namespace for a static method on clang's Lexer class; we don't directly
		611	/// deal with Lexer objects
		612	pub const Lexer = struct {
		613	pub const getLocForEndOfToken = ZigClangLexer_getLocForEndOfToken;
		614	extern fn ZigClangLexer_getLocForEndOfToken(SourceLocation, const SourceManager, const ASTUnit) SourceLocation;
		615	};
		616
610	pub const MacroDefinitionRecord = opaque {	617	pub const MacroDefinitionRecord = opaque {
611	pub const getName_getNameStart = ZigClangMacroDefinitionRecord_getName_getNameStart;	618	pub const getName_getNameStart = ZigClangMacroDefinitionRecord_getName_getNameStart;
612	extern fn ZigClangMacroDefinitionRecord_getName_getNameStart(const MacroDefinitionRecord) [:0]const u8;	619	extern fn ZigClangMacroDefinitionRecord_getName_getNameStart(const MacroDefinitionRecord) [:0]const u8;

src/translate_c.zig+4-1

...	@@ -4688,6 +4688,7 @@ fn transPreprocessorEntities(c: Context, unit: clang.ASTUnit) Error!void {	...	@@ -4688,6 +4688,7 @@ fn transPreprocessorEntities(c: Context, unit: clang.ASTUnit) Error!void {
4688	const macro = @ptrCast(*clang.MacroDefinitionRecord, entity);	4688	const macro = @ptrCast(*clang.MacroDefinitionRecord, entity);
4689	const raw_name = macro.getName_getNameStart();	4689	const raw_name = macro.getName_getNameStart();
4690	const begin_loc = macro.getSourceRange_getBegin();	4690	const begin_loc = macro.getSourceRange_getBegin();
		4691	const end_loc = clang.Lexer.getLocForEndOfToken(macro.getSourceRange_getEnd(), c.source_manager, unit);
4691		4692
4692	const name = try c.str(raw_name);	4693	const name = try c.str(raw_name);
4693	// TODO https://github.com/ziglang/zig/issues/3756	4694	// TODO https://github.com/ziglang/zig/issues/3756
...	@@ -4698,7 +4699,9 @@ fn transPreprocessorEntities(c: Context, unit: clang.ASTUnit) Error!void {	...	@@ -4698,7 +4699,9 @@ fn transPreprocessorEntities(c: Context, unit: clang.ASTUnit) Error!void {
4698	}	4699	}
4699		4700
4700	const begin_c = c.source_manager.getCharacterData(begin_loc);	4701	const begin_c = c.source_manager.getCharacterData(begin_loc);
4701	const slice = begin_c[0..mem.len(begin_c)];	4702	const end_c = c.source_manager.getCharacterData(end_loc);
		4703	const slice_len = @ptrToInt(end_c) - @ptrToInt(begin_c);
		4704	const slice = begin_c[0..slice_len];
4702		4705
4703	var tokenizer = std.c.Tokenizer{	4706	var tokenizer = std.c.Tokenizer{
4704	.buffer = slice,	4707	.buffer = slice,

src/zig_clang.cpp+7

...	@@ -3100,6 +3100,13 @@ struct ZigClangSourceLocation ZigClangMacroDefinitionRecord_getSourceRange_getEn	...	@@ -3100,6 +3100,13 @@ struct ZigClangSourceLocation ZigClangMacroDefinitionRecord_getSourceRange_getEn
3100	return bitcast(casted->getSourceRange().getEnd());	3100	return bitcast(casted->getSourceRange().getEnd());
3101	}	3101	}
3102		3102
		3103	struct ZigClangSourceLocation ZigClangLexer_getLocForEndOfToken(ZigClangSourceLocation loc, const ZigClangSourceManager sm, const ZigClangASTUnit unit) {
		3104	const clang::SourceManager casted_sm = reinterpret_cast<const clang::SourceManager >(sm);
		3105	const clang::ASTUnit casted_unit = reinterpret_cast<const clang::ASTUnit >(unit);
		3106	clang::SourceLocation endloc = clang::Lexer::getLocForEndOfToken(bitcast(loc), 0, *casted_sm, casted_unit->getLangOpts());
		3107	return bitcast(endloc);
		3108	}
		3109
3103	ZigClangRecordDecl_field_iterator ZigClangRecordDecl_field_begin(const struct ZigClangRecordDecl *self) {	3110	ZigClangRecordDecl_field_iterator ZigClangRecordDecl_field_begin(const struct ZigClangRecordDecl *self) {
3104	auto casted = reinterpret_cast<const clang::RecordDecl *>(self);	3111	auto casted = reinterpret_cast<const clang::RecordDecl *>(self);
3105	return bitcast(casted->field_begin());	3112	return bitcast(casted->field_begin());

src/zig_clang.h+2

...	@@ -966,6 +966,8 @@ ZIG_EXTERN_C const char* ZigClangSourceManager_getCharacterData(const struct Zig	...	@@ -966,6 +966,8 @@ ZIG_EXTERN_C const char* ZigClangSourceManager_getCharacterData(const struct Zig
966		966
967	ZIG_EXTERN_C struct ZigClangQualType ZigClangASTContext_getPointerType(const struct ZigClangASTContext*, struct ZigClangQualType T);	967	ZIG_EXTERN_C struct ZigClangQualType ZigClangASTContext_getPointerType(const struct ZigClangASTContext*, struct ZigClangQualType T);
968		968
		969	ZIG_EXTERN_C struct ZigClangSourceLocation ZigClangLexer_getLocForEndOfToken(struct ZigClangSourceLocation,
		970	const ZigClangSourceManager , const ZigClangASTUnit );
969		971
970	// Can return null.	972	// Can return null.
971	ZIG_EXTERN_C struct ZigClangASTUnit ZigClangLoadFromCommandLine(const char args_begin, const char *args_end,	973	ZIG_EXTERN_C struct ZigClangASTUnit ZigClangLoadFromCommandLine(const char args_begin, const char *args_end,