[WebAssembly] Make __attribute__((used)) not imply export.
Add an WASM_SYMBOL_NO_STRIP flag, so that __attribute__((used)) doesn't
need to imply exporting. When targeting Emscripten, have
WASM_SYMBOL_NO_STRIP imply exporting.
Differential Revision: https://reviews.llvm.org/D62542
llvm-svn: 370415
diff --git a/llvm/lib/MC/MCWasmObjectTargetWriter.cpp b/llvm/lib/MC/MCWasmObjectTargetWriter.cpp
index e462578..1ccb3a5 100644
--- a/llvm/lib/MC/MCWasmObjectTargetWriter.cpp
+++ b/llvm/lib/MC/MCWasmObjectTargetWriter.cpp
@@ -10,8 +10,9 @@
using namespace llvm;
-MCWasmObjectTargetWriter::MCWasmObjectTargetWriter(bool Is64Bit)
- : Is64Bit(Is64Bit) {}
+MCWasmObjectTargetWriter::MCWasmObjectTargetWriter(bool Is64Bit,
+ bool IsEmscripten)
+ : Is64Bit(Is64Bit), IsEmscripten(IsEmscripten) {}
// Pin the vtable to this object file
MCWasmObjectTargetWriter::~MCWasmObjectTargetWriter() = default;
diff --git a/llvm/lib/MC/MCWasmStreamer.cpp b/llvm/lib/MC/MCWasmStreamer.cpp
index 86fa721..e7e96ec 100644
--- a/llvm/lib/MC/MCWasmStreamer.cpp
+++ b/llvm/lib/MC/MCWasmStreamer.cpp
@@ -122,7 +122,7 @@
break;
case MCSA_NoDeadStrip:
- Symbol->setExported();
+ Symbol->setNoStrip();
break;
default:
diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp
index cb00241..5361888 100644
--- a/llvm/lib/MC/WasmObjectWriter.cpp
+++ b/llvm/lib/MC/WasmObjectWriter.cpp
@@ -258,6 +258,7 @@
// TargetObjectWriter wrappers.
bool is64Bit() const { return TargetObjectWriter->is64Bit(); }
+ bool isEmscripten() const { return TargetObjectWriter->isEmscripten(); }
void startSection(SectionBookkeeping &Section, unsigned SectionId);
void startCustomSection(SectionBookkeeping &Section, StringRef Name);
@@ -1443,8 +1444,12 @@
Flags |= wasm::WASM_SYMBOL_BINDING_LOCAL;
if (WS.isUndefined())
Flags |= wasm::WASM_SYMBOL_UNDEFINED;
- if (WS.isExported())
- Flags |= wasm::WASM_SYMBOL_EXPORTED;
+ if (WS.isNoStrip()) {
+ Flags |= wasm::WASM_SYMBOL_NO_STRIP;
+ if (isEmscripten()) {
+ Flags |= wasm::WASM_SYMBOL_EXPORTED;
+ }
+ }
if (WS.getName() != WS.getImportName())
Flags |= wasm::WASM_SYMBOL_EXPLICIT_NAME;
diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp
index 88491d9..04f5694 100644
--- a/llvm/lib/ObjectYAML/WasmYAML.cpp
+++ b/llvm/lib/ObjectYAML/WasmYAML.cpp
@@ -535,6 +535,7 @@
BCaseMask(UNDEFINED, UNDEFINED);
BCaseMask(EXPORTED, EXPORTED);
BCaseMask(EXPLICIT_NAME, EXPLICIT_NAME);
+ BCaseMask(NO_STRIP, NO_STRIP);
#undef BCaseMask
}
diff --git a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp
index 70b409c..8314de4 100644
--- a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp
+++ b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp
@@ -31,10 +31,12 @@
class WebAssemblyAsmBackend final : public MCAsmBackend {
bool Is64Bit;
+ bool IsEmscripten;
public:
- explicit WebAssemblyAsmBackend(bool Is64Bit)
- : MCAsmBackend(support::little), Is64Bit(Is64Bit) {}
+ explicit WebAssemblyAsmBackend(bool Is64Bit, bool IsEmscripten)
+ : MCAsmBackend(support::little), Is64Bit(Is64Bit),
+ IsEmscripten(IsEmscripten) {}
unsigned getNumFixupKinds() const override {
return WebAssembly::NumTargetFixupKinds;
@@ -123,11 +125,11 @@
std::unique_ptr<MCObjectTargetWriter>
WebAssemblyAsmBackend::createObjectTargetWriter() const {
- return createWebAssemblyWasmObjectWriter(Is64Bit);
+ return createWebAssemblyWasmObjectWriter(Is64Bit, IsEmscripten);
}
} // end anonymous namespace
MCAsmBackend *llvm::createWebAssemblyAsmBackend(const Triple &TT) {
- return new WebAssemblyAsmBackend(TT.isArch64Bit());
+ return new WebAssemblyAsmBackend(TT.isArch64Bit(), TT.isOSEmscripten());
}
diff --git a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h
index 7a9f59b..f2f3d20 100644
--- a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h
+++ b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h
@@ -38,7 +38,7 @@
MCAsmBackend *createWebAssemblyAsmBackend(const Triple &TT);
std::unique_ptr<MCObjectTargetWriter>
-createWebAssemblyWasmObjectWriter(bool Is64Bit);
+createWebAssemblyWasmObjectWriter(bool Is64Bit, bool IsEmscripten);
namespace WebAssembly {
enum OperandType {
diff --git a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyWasmObjectWriter.cpp b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyWasmObjectWriter.cpp
index f424b72..e7a599e 100644
--- a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyWasmObjectWriter.cpp
+++ b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyWasmObjectWriter.cpp
@@ -31,7 +31,7 @@
namespace {
class WebAssemblyWasmObjectWriter final : public MCWasmObjectTargetWriter {
public:
- explicit WebAssemblyWasmObjectWriter(bool Is64Bit);
+ explicit WebAssemblyWasmObjectWriter(bool Is64Bit, bool IsEmscripten);
private:
unsigned getRelocType(const MCValue &Target,
@@ -39,8 +39,9 @@
};
} // end anonymous namespace
-WebAssemblyWasmObjectWriter::WebAssemblyWasmObjectWriter(bool Is64Bit)
- : MCWasmObjectTargetWriter(Is64Bit) {}
+WebAssemblyWasmObjectWriter::WebAssemblyWasmObjectWriter(bool Is64Bit,
+ bool IsEmscripten)
+ : MCWasmObjectTargetWriter(Is64Bit, IsEmscripten) {}
static const MCSection *getFixupSection(const MCExpr *Expr) {
if (auto SyExp = dyn_cast<MCSymbolRefExpr>(Expr)) {
@@ -116,6 +117,6 @@
}
std::unique_ptr<MCObjectTargetWriter>
-llvm::createWebAssemblyWasmObjectWriter(bool Is64Bit) {
- return std::make_unique<WebAssemblyWasmObjectWriter>(Is64Bit);
+llvm::createWebAssemblyWasmObjectWriter(bool Is64Bit, bool IsEmscripten) {
+ return std::make_unique<WebAssemblyWasmObjectWriter>(Is64Bit, IsEmscripten);
}