Implement Microsoft-compatible mangling for decomposition declarations.

Match cl.exe's mangling for decomposition declarations.

Decomposition declarations are considered to be anonymous structs,
and use the same convention as for anonymous struct/union declarations.

Naming confirmed to match https://godbolt.org/z/K2osJa

Patch from Eric Astor <epastor@google.com>!

Differential Revision: https://reviews.llvm.org/D67202

llvm-svn: 371124
This commit is contained in:
Nico Weber 2019-09-05 21:08:50 +00:00
parent 36b0571d21
commit a47dc841cd
3 changed files with 30 additions and 14 deletions

View File

@ -56,7 +56,7 @@ private:
llvm::DenseMap<const BlockDecl*, unsigned> GlobalBlockIds;
llvm::DenseMap<const BlockDecl*, unsigned> LocalBlockIds;
llvm::DenseMap<const TagDecl*, uint64_t> AnonStructIds;
llvm::DenseMap<const NamedDecl*, uint64_t> AnonStructIds;
public:
ManglerKind getKind() const { return Kind; }
@ -82,9 +82,9 @@ public:
return Result.first->second;
}
uint64_t getAnonymousStructId(const TagDecl *TD) {
std::pair<llvm::DenseMap<const TagDecl *, uint64_t>::iterator, bool>
Result = AnonStructIds.insert(std::make_pair(TD, AnonStructIds.size()));
uint64_t getAnonymousStructId(const NamedDecl *D) {
std::pair<llvm::DenseMap<const NamedDecl *, uint64_t>::iterator, bool>
Result = AnonStructIds.insert(std::make_pair(D, AnonStructIds.size()));
return Result.first->second;
}

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@ -868,16 +868,11 @@ void MicrosoftCXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
}
if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(ND)) {
// FIXME: Invented mangling for decomposition declarations:
// [X,Y,Z]
// where X,Y,Z are the names of the bindings.
llvm::SmallString<128> Name("[");
for (auto *BD : DD->bindings()) {
if (Name.size() > 1)
Name += ',';
Name += BD->getDeclName().getAsIdentifierInfo()->getName();
}
Name += ']';
// Decomposition declarations are considered anonymous, and get
// numbered with a $S prefix.
llvm::SmallString<64> Name("$S");
// Get a unique id for the anonymous struct.
Name += llvm::utostr(Context.getAnonymousStructId(DD) + 1);
mangleSourceName(Name);
break;
}

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@ -0,0 +1,21 @@
// RUN: %clang_cc1 -std=c++1z -fms-extensions -emit-llvm %s -o - -triple=i386-pc-win32 -fms-compatibility-version=19.10 | FileCheck -allow-deprecated-dag-overlap %s --check-prefix=CHECK --check-prefix=MSVC2017
// RUN: %clang_cc1 -std=c++1z -fms-extensions -emit-llvm %s -o - -triple=i386-pc-win32 -fms-compatibility-version=19.00 | FileCheck -allow-deprecated-dag-overlap %s --check-prefix=CHECK --check-prefix=MSVC2015
struct S {
int x;
double y;
};
S f();
// CHECK-DAG: "?$S1@@3US@@B"
const auto [x0, y0] = f();
// CHECK-DAG: "?$S2@@3US@@B"
const auto [x1, y1] = f();
static union {
int a;
double b;
};
// CHECK-DAG: "?$S4@@3US@@B"
const auto [x2, y2] = f();