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Differential D125257

[demangler] Avoid special-subst code duplication
ClosedPublic

Authored by urnathan on May 9 2022, 12:13 PM.

Details

Reviewers
MaskRay
dblaikie
Group Reviewers
Restricted Project
Commits
rG562ce1592456: [demangler] Avoid special-subst code duplication
Summary

We need to expand special substitutions names in four different ways, and were doing it with 4 different switch blocks. This refactors the demangler to only have one conversion from enum to string, and derive the other 3 needs off that.

If we base the SpecialSubstitution node from the ExpandedSpecialSubstitution, this reuse becomes simpler. While this may seem the wrong derivation, it works out quite well, as the SpecialSubstitution can then use the later's getBaseName and remove an unneeded 'basic_' prefix, for those substitutions that are instantiations (to known typedef).

Similarly all those instantiations use the same set of template arguments (with 'basic_string', getting an additional 'allocator' arg). There's no need to write each one separately.

Expansion tests were added in D123134, and remain unchanged.

Diff Detail

Event Timeline

urnathan created this revision.May 9 2022, 12:13 PM
Herald added a project: Restricted Project. · View Herald TranscriptMay 9 2022, 12:13 PM
Herald added a subscriber: StephenFan. · View Herald Transcript
urnathan requested review of this revision.May 9 2022, 12:13 PM
Herald added a project: Restricted Project. · View Herald TranscriptMay 9 2022, 12:13 PM
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Harbormaster completed remote builds in B163537: Diff 428154.May 9 2022, 2:24 PM
urnathan updated this revision to Diff 428909.May 12 2022, 5:18 AM

Address CI issue

Harbormaster completed remote builds in B164080: Diff 428909.May 12 2022, 6:59 AM
dblaikie accepted this revision.May 12 2022, 3:04 PM

Looks about right at a glance - thanks!

This revision is now accepted and ready to land.May 12 2022, 3:04 PM
MaskRay accepted this revision.May 12 2022, 3:37 PM
This revision was landed with ongoing or failed builds.May 13 2022, 4:35 AM
Closed by commit rG562ce1592456: [demangler] Avoid special-subst code duplication (authored by urnathan). · Explain Why
This revision was automatically updated to reflect the committed changes.
urnathan added a commit: rG562ce1592456: [demangler] Avoid special-subst code duplication.
Herald added a project: Restricted Project. · View Herald TranscriptMay 13 2022, 4:35 AM
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Revision Contents

PathSize
libcxxabi/
src/
demangle/
110 lines
llvm/
include/
llvm/
Demangle/
110 lines

Diff 429201

libcxxabi/src/demangle/ItaniumDemangle.h

Show First 20 Lines • Show All 1,500 Lines • ▼ Show 20 Linesenum class SpecialSubKind {
allocator, allocator,
basic_string, basic_string,
string, string,
istream, istream,
ostream, ostream,
iostream, iostream,
}; };
class ExpandedSpecialSubstitution final : public Node { class SpecialSubstitution;
class ExpandedSpecialSubstitution : public Node {
protected:
SpecialSubKind SSK; SpecialSubKind SSK;
ExpandedSpecialSubstitution(SpecialSubKind SSK_, Kind K_)
: Node(K_), SSK(SSK_) {}
public: public:
ExpandedSpecialSubstitution(SpecialSubKind SSK_) ExpandedSpecialSubstitution(SpecialSubKind SSK_)
: Node(KExpandedSpecialSubstitution), SSK(SSK_) {} : ExpandedSpecialSubstitution(SSK_, KExpandedSpecialSubstitution) {}
inline ExpandedSpecialSubstitution(SpecialSubstitution const *);
template<typename Fn> void match(Fn F) const { F(SSK); } template<typename Fn> void match(Fn F) const { F(SSK); }
protected:
bool isInstantiation() const {
return unsigned(SSK) >= unsigned(SpecialSubKind::string);
}
StringView getBaseName() const override { StringView getBaseName() const override {
switch (SSK) { switch (SSK) {
case SpecialSubKind::allocator: case SpecialSubKind::allocator:
return StringView("allocator"); return StringView("allocator");
case SpecialSubKind::basic_string: case SpecialSubKind::basic_string:
return StringView("basic_string"); return StringView("basic_string");
case SpecialSubKind::string: case SpecialSubKind::string:
return StringView("basic_string"); return StringView("basic_string");
case SpecialSubKind::istream: case SpecialSubKind::istream:
return StringView("basic_istream"); return StringView("basic_istream");
case SpecialSubKind::ostream: case SpecialSubKind::ostream:
return StringView("basic_ostream"); return StringView("basic_ostream");
case SpecialSubKind::iostream: case SpecialSubKind::iostream:
return StringView("basic_iostream"); return StringView("basic_iostream");
} }
DEMANGLE_UNREACHABLE; DEMANGLE_UNREACHABLE;
} }
private:
void printLeft(OutputBuffer &OB) const override { void printLeft(OutputBuffer &OB) const override {
switch (SSK) { OB << "std::" << getBaseName();
case SpecialSubKind::allocator: if (isInstantiation()) {
OB += "std::allocator"; OB << "<char, std::char_traits<char>";
break; if (SSK == SpecialSubKind::string)
case SpecialSubKind::basic_string: OB << ", std::allocator<char>";
OB += "std::basic_string"; OB << ">";
break;
case SpecialSubKind::string:
OB += "std::basic_string<char, std::char_traits<char>, "
"std::allocator<char>>";
break;
case SpecialSubKind::istream:
OB += "std::basic_istream<char, std::char_traits<char>>";
break;
case SpecialSubKind::ostream:
OB += "std::basic_ostream<char, std::char_traits<char>>";
break;
case SpecialSubKind::iostream:
OB += "std::basic_iostream<char, std::char_traits<char>>";
break;
} }
} }
}; };
class SpecialSubstitution final : public Node { class SpecialSubstitution final : public ExpandedSpecialSubstitution {
public: public:
SpecialSubKind SSK;
SpecialSubstitution(SpecialSubKind SSK_) SpecialSubstitution(SpecialSubKind SSK_)
: Node(KSpecialSubstitution), SSK(SSK_) {} : ExpandedSpecialSubstitution(SSK_, KSpecialSubstitution) {}
template<typename Fn> void match(Fn F) const { F(SSK); } template<typename Fn> void match(Fn F) const { F(SSK); }
StringView getBaseName() const override { StringView getBaseName() const override {
switch (SSK) { auto SV = ExpandedSpecialSubstitution::getBaseName ();
case SpecialSubKind::allocator: if (isInstantiation()) {
return StringView("allocator"); // The instantiations are typedefs that drop the "basic_" prefix.
case SpecialSubKind::basic_string: assert(SV.startsWith("basic_"));
return StringView("basic_string"); SV = SV.dropFront(sizeof("basic_") - 1);
case SpecialSubKind::string:
return StringView("string");
case SpecialSubKind::istream:
return StringView("istream");
case SpecialSubKind::ostream:
return StringView("ostream");
case SpecialSubKind::iostream:
return StringView("iostream");
} }
DEMANGLE_UNREACHABLE; return SV;
} }
void printLeft(OutputBuffer &OB) const override { void printLeft(OutputBuffer &OB) const override {
switch (SSK) { OB << "std::" << getBaseName();
case SpecialSubKind::allocator:
OB += "std::allocator";
break;
case SpecialSubKind::basic_string:
OB += "std::basic_string";
break;
case SpecialSubKind::string:
OB += "std::string";
break;
case SpecialSubKind::istream:
OB += "std::istream";
break;
case SpecialSubKind::ostream:
OB += "std::ostream";
break;
case SpecialSubKind::iostream:
OB += "std::iostream";
break;
}
} }
}; };
inline ExpandedSpecialSubstitution::ExpandedSpecialSubstitution(
SpecialSubstitution const *SS)
: ExpandedSpecialSubstitution(SS->SSK) {}
class CtorDtorName final : public Node { class CtorDtorName final : public Node {
const Node *Basename; const Node *Basename;
const bool IsDtor; const bool IsDtor;
const int Variant; const int Variant;
public: public:
CtorDtorName(const Node *Basename_, bool IsDtor_, int Variant_) CtorDtorName(const Node *Basename_, bool IsDtor_, int Variant_)
: Node(KCtorDtorName), Basename(Basename_), IsDtor(IsDtor_), : Node(KCtorDtorName), Basename(Basename_), IsDtor(IsDtor_),
▲ Show 20 Lines • Show All 1,503 Lines • ▼ Show 20 Lines
// ::= D2 # base object destructor // ::= D2 # base object destructor
// extension ::= D4 # gcc old-style "[unified]" destructor // extension ::= D4 # gcc old-style "[unified]" destructor
// extension ::= D5 # the COMDAT used for dtors // extension ::= D5 # the COMDAT used for dtors
template <typename Derived, typename Alloc> template <typename Derived, typename Alloc>
Node * Node *
AbstractManglingParser<Derived, Alloc>::parseCtorDtorName(Node *&SoFar, AbstractManglingParser<Derived, Alloc>::parseCtorDtorName(Node *&SoFar,
NameState *State) { NameState *State) {
if (SoFar->getKind() == Node::KSpecialSubstitution) { if (SoFar->getKind() == Node::KSpecialSubstitution) {
auto SSK = static_cast<SpecialSubstitution *>(SoFar)->SSK; // Expand the special substitution.
switch (SSK) { SoFar = make<ExpandedSpecialSubstitution>(
case SpecialSubKind::string: static_cast<SpecialSubstitution *>(SoFar));
case SpecialSubKind::istream:
case SpecialSubKind::ostream:
case SpecialSubKind::iostream:
SoFar = make<ExpandedSpecialSubstitution>(SSK);
if (!SoFar) if (!SoFar)
return nullptr; return nullptr;
break;
default:
break;
}
} }
if (consumeIf('C')) { if (consumeIf('C')) {
bool IsInherited = consumeIf('I'); bool IsInherited = consumeIf('I');
if (look() != '1' && look() != '2' && look() != '3' && look() != '4' && if (look() != '1' && look() != '2' && look() != '3' && look() != '4' &&
look() != '5') look() != '5')
return nullptr; return nullptr;
int Variant = look() - '0'; int Variant = look() - '0';
▲ Show 20 Lines • Show All 2,365 Lines • Show Last 20 Lines

llvm/include/llvm/Demangle/ItaniumDemangle.h

Show First 20 Lines • Show All 1,500 Lines • ▼ Show 20 Linesenum class SpecialSubKind {
allocator, allocator,
basic_string, basic_string,
string, string,
istream, istream,
ostream, ostream,
iostream, iostream,
}; };
class ExpandedSpecialSubstitution final : public Node { class SpecialSubstitution;
class ExpandedSpecialSubstitution : public Node {
protected:
SpecialSubKind SSK; SpecialSubKind SSK;
ExpandedSpecialSubstitution(SpecialSubKind SSK_, Kind K_)
: Node(K_), SSK(SSK_) {}
public: public:
ExpandedSpecialSubstitution(SpecialSubKind SSK_) ExpandedSpecialSubstitution(SpecialSubKind SSK_)
: Node(KExpandedSpecialSubstitution), SSK(SSK_) {} : ExpandedSpecialSubstitution(SSK_, KExpandedSpecialSubstitution) {}
inline ExpandedSpecialSubstitution(SpecialSubstitution const *);
template<typename Fn> void match(Fn F) const { F(SSK); } template<typename Fn> void match(Fn F) const { F(SSK); }
protected:
bool isInstantiation() const {
return unsigned(SSK) >= unsigned(SpecialSubKind::string);
}
StringView getBaseName() const override { StringView getBaseName() const override {
switch (SSK) { switch (SSK) {
case SpecialSubKind::allocator: case SpecialSubKind::allocator:
return StringView("allocator"); return StringView("allocator");
case SpecialSubKind::basic_string: case SpecialSubKind::basic_string:
return StringView("basic_string"); return StringView("basic_string");
case SpecialSubKind::string: case SpecialSubKind::string:
return StringView("basic_string"); return StringView("basic_string");
case SpecialSubKind::istream: case SpecialSubKind::istream:
return StringView("basic_istream"); return StringView("basic_istream");
case SpecialSubKind::ostream: case SpecialSubKind::ostream:
return StringView("basic_ostream"); return StringView("basic_ostream");
case SpecialSubKind::iostream: case SpecialSubKind::iostream:
return StringView("basic_iostream"); return StringView("basic_iostream");
} }
DEMANGLE_UNREACHABLE; DEMANGLE_UNREACHABLE;
} }
private:
void printLeft(OutputBuffer &OB) const override { void printLeft(OutputBuffer &OB) const override {
switch (SSK) { OB << "std::" << getBaseName();
case SpecialSubKind::allocator: if (isInstantiation()) {
OB += "std::allocator"; OB << "<char, std::char_traits<char>";
break; if (SSK == SpecialSubKind::string)
case SpecialSubKind::basic_string: OB << ", std::allocator<char>";
OB += "std::basic_string"; OB << ">";
break;
case SpecialSubKind::string:
OB += "std::basic_string<char, std::char_traits<char>, "
"std::allocator<char>>";
break;
case SpecialSubKind::istream:
OB += "std::basic_istream<char, std::char_traits<char>>";
break;
case SpecialSubKind::ostream:
OB += "std::basic_ostream<char, std::char_traits<char>>";
break;
case SpecialSubKind::iostream:
OB += "std::basic_iostream<char, std::char_traits<char>>";
break;
} }
} }
}; };
class SpecialSubstitution final : public Node { class SpecialSubstitution final : public ExpandedSpecialSubstitution {
public: public:
SpecialSubKind SSK;
SpecialSubstitution(SpecialSubKind SSK_) SpecialSubstitution(SpecialSubKind SSK_)
: Node(KSpecialSubstitution), SSK(SSK_) {} : ExpandedSpecialSubstitution(SSK_, KSpecialSubstitution) {}
template<typename Fn> void match(Fn F) const { F(SSK); } template<typename Fn> void match(Fn F) const { F(SSK); }
StringView getBaseName() const override { StringView getBaseName() const override {
switch (SSK) { auto SV = ExpandedSpecialSubstitution::getBaseName ();
case SpecialSubKind::allocator: if (isInstantiation()) {
return StringView("allocator"); // The instantiations are typedefs that drop the "basic_" prefix.
case SpecialSubKind::basic_string: assert(SV.startsWith("basic_"));
return StringView("basic_string"); SV = SV.dropFront(sizeof("basic_") - 1);
case SpecialSubKind::string:
return StringView("string");
case SpecialSubKind::istream:
return StringView("istream");
case SpecialSubKind::ostream:
return StringView("ostream");
case SpecialSubKind::iostream:
return StringView("iostream");
} }
DEMANGLE_UNREACHABLE; return SV;
} }
void printLeft(OutputBuffer &OB) const override { void printLeft(OutputBuffer &OB) const override {
switch (SSK) { OB << "std::" << getBaseName();
case SpecialSubKind::allocator:
OB += "std::allocator";
break;
case SpecialSubKind::basic_string:
OB += "std::basic_string";
break;
case SpecialSubKind::string:
OB += "std::string";
break;
case SpecialSubKind::istream:
OB += "std::istream";
break;
case SpecialSubKind::ostream:
OB += "std::ostream";
break;
case SpecialSubKind::iostream:
OB += "std::iostream";
break;
}
} }
}; };
inline ExpandedSpecialSubstitution::ExpandedSpecialSubstitution(
SpecialSubstitution const *SS)
: ExpandedSpecialSubstitution(SS->SSK) {}
class CtorDtorName final : public Node { class CtorDtorName final : public Node {
const Node *Basename; const Node *Basename;
const bool IsDtor; const bool IsDtor;
const int Variant; const int Variant;
public: public:
CtorDtorName(const Node *Basename_, bool IsDtor_, int Variant_) CtorDtorName(const Node *Basename_, bool IsDtor_, int Variant_)
: Node(KCtorDtorName), Basename(Basename_), IsDtor(IsDtor_), : Node(KCtorDtorName), Basename(Basename_), IsDtor(IsDtor_),
▲ Show 20 Lines • Show All 1,503 Lines • ▼ Show 20 Lines
// ::= D2 # base object destructor // ::= D2 # base object destructor
// extension ::= D4 # gcc old-style "[unified]" destructor // extension ::= D4 # gcc old-style "[unified]" destructor
// extension ::= D5 # the COMDAT used for dtors // extension ::= D5 # the COMDAT used for dtors
template <typename Derived, typename Alloc> template <typename Derived, typename Alloc>
Node * Node *
AbstractManglingParser<Derived, Alloc>::parseCtorDtorName(Node *&SoFar, AbstractManglingParser<Derived, Alloc>::parseCtorDtorName(Node *&SoFar,
NameState *State) { NameState *State) {
if (SoFar->getKind() == Node::KSpecialSubstitution) { if (SoFar->getKind() == Node::KSpecialSubstitution) {
auto SSK = static_cast<SpecialSubstitution *>(SoFar)->SSK; // Expand the special substitution.
switch (SSK) { SoFar = make<ExpandedSpecialSubstitution>(
case SpecialSubKind::string: static_cast<SpecialSubstitution *>(SoFar));
case SpecialSubKind::istream:
case SpecialSubKind::ostream:
case SpecialSubKind::iostream:
SoFar = make<ExpandedSpecialSubstitution>(SSK);
if (!SoFar) if (!SoFar)
return nullptr; return nullptr;
break;
default:
break;
}
} }
if (consumeIf('C')) { if (consumeIf('C')) {
bool IsInherited = consumeIf('I'); bool IsInherited = consumeIf('I');
if (look() != '1' && look() != '2' && look() != '3' && look() != '4' && if (look() != '1' && look() != '2' && look() != '3' && look() != '4' &&
look() != '5') look() != '5')
return nullptr; return nullptr;
int Variant = look() - '0'; int Variant = look() - '0';
▲ Show 20 Lines • Show All 2,365 Lines • Show Last 20 Lines