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
diff --git a/clang/include/clang/AST/Mangle.h b/clang/include/clang/AST/Mangle.h
index e3c95dd..5db5c5b 100644
--- a/clang/include/clang/AST/Mangle.h
+++ b/clang/include/clang/AST/Mangle.h
@@ -56,7 +56,7 @@
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 @@
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;
}
diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index f7a456e..7ad8b52 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -868,16 +868,11 @@
}
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;
}
diff --git a/clang/test/CodeGenCXX/mangle-ms-cxx17.cpp b/clang/test/CodeGenCXX/mangle-ms-cxx17.cpp
new file mode 100644
index 0000000..897f0d6
--- /dev/null
+++ b/clang/test/CodeGenCXX/mangle-ms-cxx17.cpp
@@ -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();