maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

msabi: Fix exponential mangling time for even more contrived inputs 

This is a follow-up to r362293 which fixed exponential time needed
for mangling certain templates. This fixes the same issue if that
template pattern happens in template arguments > 10: The first
ten template arguments can use back references, and r362293 added
caching for back references. For latter arguments, we have to add
a cache for the mangling itself instead.

Fixes PR42091 even more.

Differential Revision: https://reviews.llvm.org/D62780

llvm-svn: 362560
This commit is contained in:
Nico Weber 2019-06-04 23:27:40 +00:00
parent 5e312be0fa
commit 487077698c
2 changed files with 55 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
clang/lib/AST/MicrosoftMangle.cpp
View File

@ -31,6 +31,7 @@
#include "llvm/Support/xxhash.h"
#include "llvm/Support/MD5.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/StringSaver.h"
using namespace clang;
@ -268,6 +269,11 @@ class MicrosoftCXXNameMangler {
ArgBackRefMap FunArgBackReferences;
ArgBackRefMap TemplateArgBackReferences;
typedef llvm::DenseMap<const void *, StringRef> TemplateArgStringMap;
TemplateArgStringMap TemplateArgStrings;
llvm::StringSaver TemplateArgStringStorage;
llvm::BumpPtrAllocator TemplateArgStringStorageAlloc;
typedef std::set<std::pair<int, bool>> PassObjectSizeArgsSet;
PassObjectSizeArgsSet PassObjectSizeArgs;
@ -282,18 +288,21 @@ public:
MicrosoftCXXNameMangler(MicrosoftMangleContextImpl &C, raw_ostream &Out_)
: Context(C), Out(Out_), Structor(nullptr), StructorType(-1),
TemplateArgStringStorage(TemplateArgStringStorageAlloc),
PointersAre64Bit(C.getASTContext().getTargetInfo().getPointerWidth(0) ==
64) {}
MicrosoftCXXNameMangler(MicrosoftMangleContextImpl &C, raw_ostream &Out_,
const CXXConstructorDecl *D, CXXCtorType Type)
: Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
TemplateArgStringStorage(TemplateArgStringStorageAlloc),
PointersAre64Bit(C.getASTContext().getTargetInfo().getPointerWidth(0) ==
64) {}
MicrosoftCXXNameMangler(MicrosoftMangleContextImpl &C, raw_ostream &Out_,
const CXXDestructorDecl *D, CXXDtorType Type)
: Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
TemplateArgStringStorage(TemplateArgStringStorageAlloc),
PointersAre64Bit(C.getASTContext().getTargetInfo().getPointerWidth(0) ==
64) {}
@ -809,24 +818,34 @@ void MicrosoftCXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
// TD / TemplateArg pairs.
ArgBackRefMap::iterator Found = TemplateArgBackReferences.find(ND);
if (Found == TemplateArgBackReferences.end()) {
// Mangle full template name into temporary buffer.
llvm::SmallString<64> TemplateMangling;
llvm::raw_svector_ostream Stream(TemplateMangling);
MicrosoftCXXNameMangler Extra(Context, Stream);
Extra.mangleTemplateInstantiationName(TD, *TemplateArgs);
// Use the string backref vector to possibly get a back reference.
mangleSourceName(TemplateMangling);
TemplateArgStringMap::iterator Found = TemplateArgStrings.find(ND);
if (Found == TemplateArgStrings.end()) {
// Mangle full template name into temporary buffer.
llvm::SmallString<64> TemplateMangling;
llvm::raw_svector_ostream Stream(TemplateMangling);
MicrosoftCXXNameMangler Extra(Context, Stream);
Extra.mangleTemplateInstantiationName(TD, *TemplateArgs);
// Memoize back reference for this type.
BackRefVec::iterator StringFound =
llvm::find(NameBackReferences, TemplateMangling);
if (StringFound != NameBackReferences.end()) {
TemplateArgBackReferences[ND] =
StringFound - NameBackReferences.begin();
// Use the string backref vector to possibly get a back reference.
mangleSourceName(TemplateMangling);
// Memoize back reference for this type if one exist, else memoize
// the mangling itself.
BackRefVec::iterator StringFound =
llvm::find(NameBackReferences, TemplateMangling);
if (StringFound != NameBackReferences.end()) {
TemplateArgBackReferences[ND] =
StringFound - NameBackReferences.begin();
} else {
TemplateArgStrings[ND] =
TemplateArgStringStorage.save(TemplateMangling.str());
}
} else {
Out << Found->second; // Outputs a StringRef.
}
} else {
Out << Found->second;
Out << Found->second; // Outputs a back reference (an int).
}
return;
}

22
clang/test/CodeGenCXX/mangle-ms-back-references-pr13207.cpp
View File

@ -232,3 +232,25 @@ using B6 = Food<B5, B4, B3, B2, B1, B0, B0, B0, B0, B0, B5, B5, B5, B5, B5, B5,
void f(B6 a) {}
// CHECK: "?f@@YAXU?$Food@U?$Food@U?$Food@U?$Food@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U3@U3@U3@U3@U3@U3@U3@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U4@U4@U4@U4@U4@U4@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U3@U3@U3@U3@U3@U3@U3@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U5@U5@U5@U5@U5@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U3@U3@U3@U3@U3@U3@U3@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U4@U4@U4@U4@U4@U4@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U3@U3@U3@U3@U3@U3@U3@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U2@U2@U2@U2@U2@U2@U2@U2@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@U?$Food@HHHHHHHHHHHHHHHHHHHH@@U6@U6@U6@U6@U1@U1@U1@U1@U1@U1@U1@U1@U1@U1@@@@Z"
// Similar to the previous case, except that the later arguments aren't
// present in the earlier ones and hence aren't in the backref cache.
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7,
class T8, class T9, class T10, class T11, class T12, class T13,
class T14, class T15, class T16, class T17, class T18, class T19,
class T20>
struct Fooe {};
using C0 = Fooe<int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, int>;
using C1 = Fooe<C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0>;
using C2 = Fooe<C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1>;
using C3 = Fooe<C1, C1, C0, C0, C0, C0, C0, C0, C0, C0, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2>;
using C4 = Fooe<C2, C2, C1, C0, C0, C0, C0, C0, C0, C0, C3, C3, C3, C3, C3, C3, C3, C3, C3, C3>;
using C5 = Fooe<C3, C3, C2, C1, C0, C0, C0, C0, C0, C0, C4, C4, C4, C4, C4, C4, C4, C4, C4, C4>;
using C6 = Fooe<C4, C4, C3, C2, C1, C0, C0, C0, C0, C0, C5, C5, C5, C5, C5, C5, C5, C5, C5, C5>;
using C7 = Fooe<C5, C4, C3, C2, C1, C0, C0, C0, C0, C0, C6, C6, C6, C6, C6, C6, C6, C6, C6, C6>;
// This too should take milliseconds, not minutes.
void f(C7 a) {}
// CHECK: "??@f23afdfb44276eaa53a5575352cf0ebc@"