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-rw-r--r--clang/lib/AST/MicrosoftMangle.cpp174
1 files changed, 174 insertions, 0 deletions
diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index d982df04fe9..9dfd2af8bb6 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -20,6 +20,7 @@
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
+#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/VTableBuilder.h"
#include "clang/Basic/ABI.h"
@@ -27,6 +28,7 @@
#include "clang/Basic/TargetInfo.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
+#include "llvm/Support/MathExtras.h"
using namespace clang;
@@ -93,6 +95,7 @@ public:
MicrosoftMangleContextImpl(ASTContext &Context, DiagnosticsEngine &Diags)
: MicrosoftMangleContext(Context, Diags) {}
bool shouldMangleCXXName(const NamedDecl *D) override;
+ bool shouldMangleStringLiteral(const StringLiteral *SL) override;
void mangleCXXName(const NamedDecl *D, raw_ostream &Out) override;
void mangleVirtualMemPtrThunk(const CXXMethodDecl *MD, raw_ostream &) override;
void mangleThunk(const CXXMethodDecl *MD, const ThunkInfo &Thunk,
@@ -118,6 +121,7 @@ public:
void mangleDynamicInitializer(const VarDecl *D, raw_ostream &Out) override;
void mangleDynamicAtExitDestructor(const VarDecl *D,
raw_ostream &Out) override;
+ void mangleStringLiteral(const StringLiteral *SL, raw_ostream &Out) override;
bool getNextDiscriminator(const NamedDecl *ND, unsigned &disc) {
// Lambda closure types are already numbered.
if (isLambda(ND))
@@ -321,6 +325,13 @@ bool MicrosoftMangleContextImpl::shouldMangleCXXName(const NamedDecl *D) {
return true;
}
+bool
+MicrosoftMangleContextImpl::shouldMangleStringLiteral(const StringLiteral *SL) {
+ return SL->isAscii() || SL->isWide();
+ // TODO: This needs to be updated when MSVC gains support for Unicode
+ // literals.
+}
+
void MicrosoftCXXNameMangler::mangle(const NamedDecl *D,
StringRef Prefix) {
// MSVC doesn't mangle C++ names the same way it mangles extern "C" names.
@@ -2315,6 +2326,169 @@ MicrosoftMangleContextImpl::mangleDynamicAtExitDestructor(const VarDecl *D,
mangleInitFiniStub(D, Out, 'F');
}
+void MicrosoftMangleContextImpl::mangleStringLiteral(const StringLiteral *SL,
+ raw_ostream &Out) {
+ // <char-type> ::= 0 # char
+ // ::= 1 # wchar_t
+ // ::= ??? # char16_t/char32_t will need a mangling too...
+ //
+ // <literal-length> ::= <non-negative integer> # the length of the literal
+ //
+ // <encoded-crc> ::= <hex digit>+ @ # crc of the literal including
+ // # null-terminator
+ //
+ // <encoded-string> ::= <simple character> # uninteresting character
+ // ::= '?$' <hex digit> <hex digit> # these two nibbles
+ // # encode the byte for the
+ // # character
+ // ::= '?' [a-z] # \xe1 - \xfa
+ // ::= '?' [A-Z] # \xc1 - \xda
+ // ::= '?' [0-9] # [,/\:. \n\t'-]
+ //
+ // <literal> ::= '??_C@_' <char-type> <literal-length> <encoded-crc>
+ // <encoded-string> '@'
+ MicrosoftCXXNameMangler Mangler(*this, Out);
+ Mangler.getStream() << "\01??_C@_";
+
+ // <char-type>: The "kind" of string literal is encoded into the mangled name.
+ // TODO: This needs to be updated when MSVC gains support for unicode
+ // literals.
+ if (SL->isAscii())
+ Mangler.getStream() << '0';
+ else if (SL->isWide())
+ Mangler.getStream() << '1';
+ else
+ llvm_unreachable("unexpected string literal kind!");
+
+ // <literal-length>: The next part of the mangled name consists of the length
+ // of the string.
+ // The StringLiteral does not consider the NUL terminator byte(s) but the
+ // mangling does.
+ // N.B. The length is in terms of bytes, not characters.
+ Mangler.mangleNumber(SL->getByteLength() + SL->getCharByteWidth());
+
+ // We will use the "Rocksoft^tm Model CRC Algorithm" to describe the
+ // properties of our CRC:
+ // Width : 32
+ // Poly : 04C11DB7
+ // Init : FFFFFFFF
+ // RefIn : True
+ // RefOut : True
+ // XorOut : 00000000
+ // Check : 340BC6D9
+ uint32_t CRC = 0xFFFFFFFFU;
+
+ auto UpdateCRC = [&CRC](char Byte) {
+ for (unsigned i = 0; i < 8; ++i) {
+ bool Bit = CRC & 0x80000000U;
+ if (Byte & (1U << i))
+ Bit = !Bit;
+ CRC <<= 1;
+ if (Bit)
+ CRC ^= 0x04C11DB7U;
+ }
+ };
+
+ // CRC all the bytes of the StringLiteral.
+ for (char Byte : SL->getBytes())
+ UpdateCRC(Byte);
+
+ // The NUL terminator byte(s) were not present earlier,
+ // we need to manually process those bytes into the CRC.
+ for (unsigned NullTerminator = 0; NullTerminator < SL->getCharByteWidth();
+ ++NullTerminator)
+ UpdateCRC('\x00');
+
+ // The literature refers to the process of reversing the bits in the final CRC
+ // output as "reflection".
+ CRC = llvm::reverseBits(CRC);
+
+ // <encoded-crc>: The CRC is encoded utilizing the standard number mangling
+ // scheme.
+ Mangler.mangleNumber(CRC);
+
+ // <encoded-crc>: The mangled name also contains the first 32 _characters_
+ // (including null-terminator bytes) of the StringLiteral.
+ // Each character is encoded by splitting them into bytes and then encoding
+ // the constituent bytes.
+ auto MangleByte = [&Mangler](char Byte) {
+ // There are five different manglings for characters:
+ // - [a-zA-Z0-9_$]: A one-to-one mapping.
+ // - ?[a-z]: The range from \xe1 to \xfa.
+ // - ?[A-Z]: The range from \xc1 to \xda.
+ // - ?[0-9]: The set of [,/\:. \n\t'-].
+ // - ?$XX: A fallback which maps nibbles.
+ if ((Byte >= 'a' && Byte <= 'z') || (Byte >= 'A' && Byte <= 'Z') ||
+ (Byte >= '0' && Byte <= '9') || Byte == '_' || Byte == '$') {
+ Mangler.getStream() << Byte;
+ } else if (Byte >= '\xe1' && Byte <= '\xfa') {
+ Mangler.getStream() << '?' << static_cast<char>('a' + (Byte - '\xe1'));
+ } else if (Byte >= '\xc1' && Byte <= '\xda') {
+ Mangler.getStream() << '?' << static_cast<char>('A' + (Byte - '\xc1'));
+ } else {
+ switch (Byte) {
+ case ',':
+ Mangler.getStream() << "?0";
+ break;
+ case '/':
+ Mangler.getStream() << "?1";
+ break;
+ case '\\':
+ Mangler.getStream() << "?2";
+ break;
+ case ':':
+ Mangler.getStream() << "?3";
+ break;
+ case '.':
+ Mangler.getStream() << "?4";
+ break;
+ case ' ':
+ Mangler.getStream() << "?5";
+ break;
+ case '\n':
+ Mangler.getStream() << "?6";
+ break;
+ case '\t':
+ Mangler.getStream() << "?7";
+ break;
+ case '\'':
+ Mangler.getStream() << "?8";
+ break;
+ case '-':
+ Mangler.getStream() << "?9";
+ break;
+ default:
+ Mangler.getStream() << "?$";
+ Mangler.getStream() << static_cast<char>('A' + ((Byte >> 4) & 0xf));
+ Mangler.getStream() << static_cast<char>('A' + (Byte & 0xf));
+ break;
+ }
+ }
+ };
+
+ auto MangleChar = [&Mangler, &MangleByte, &SL](uint32_t CodeUnit) {
+ if (SL->getCharByteWidth() == 1) {
+ MangleByte(static_cast<char>(CodeUnit));
+ } else if (SL->getCharByteWidth() == 2) {
+ MangleByte(static_cast<char>((CodeUnit >> 16) & 0xff));
+ MangleByte(static_cast<char>(CodeUnit & 0xff));
+ } else {
+ llvm_unreachable("unsupported CharByteWidth");
+ }
+ };
+
+ // Enforce our 32 character max.
+ unsigned NumCharsToMangle = std::min(32U, SL->getLength());
+ for (unsigned i = 0; i < NumCharsToMangle; ++i)
+ MangleChar(SL->getCodeUnit(i));
+
+ // Encode the NUL terminator if there is room.
+ if (NumCharsToMangle < 32)
+ MangleChar(0);
+
+ Mangler.getStream() << '@';
+}
+
MicrosoftMangleContext *
MicrosoftMangleContext::create(ASTContext &Context, DiagnosticsEngine &Diags) {
return new MicrosoftMangleContextImpl(Context, Diags);
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