Add code to the target lowering object file module to handle module flags.
The MachO back-end needs to emit the garbage collection flags specified in the
module flags. This is a WIP, so the front-end hasn't been modified to emit these
flags just yet. Documentation and front-end switching to occur soon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150507 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 241f200..80d90d6 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -857,6 +857,10 @@
EmitVisibility(Name, V, false);
}
+ // Emit module flags.
+ if (NamedMDNode *ModFlags = M.getModuleFlagsMetadata())
+ getObjFileLowering().emitModuleFlags(OutStreamer, ModFlags, Mang, TM);
+
// Finalize debug and EH information.
if (DE) {
{
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 3a71f4f..1b62419 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -17,6 +17,7 @@
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
+#include "llvm/Module.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
@@ -370,6 +371,65 @@
// MachO
//===----------------------------------------------------------------------===//
+/// emitModuleFlags - Emit the module flags that specify the garbage collection
+/// information.
+void TargetLoweringObjectFileMachO::
+emitModuleFlags(MCStreamer &Streamer, NamedMDNode *ModFlags,
+ Mangler *Mang, const TargetMachine &TM) const {
+ StringRef Version("Objective-C Image Info Version");
+ StringRef SectionSpec("Objective-C Image Info Section");
+ StringRef GC("Objective-C Garbage Collection");
+ StringRef GCOnly("Objective-C GC Only");
+
+ unsigned VersionVal = 0;
+ unsigned GCFlags = 0;
+ StringRef Section;
+
+ for (unsigned i = 0, e = ModFlags->getNumOperands(); i != e; ++i) {
+ MDNode *Flag = ModFlags->getOperand(i);
+ Value *Behavior = Flag->getOperand(0);
+
+ // Ignore flags with 'Require' behavior.
+ if (cast<ConstantInt>(Behavior)->getZExtValue() == Module::Require)
+ continue;
+
+ Value *Key = Flag->getOperand(1);
+ Value *Val = Flag->getOperand(2);
+
+ StringRef KeyStr = cast<MDString>(Key)->getString();
+
+ if (KeyStr == Version)
+ VersionVal = cast<ConstantInt>(Val)->getZExtValue();
+ else if (KeyStr == GC || KeyStr == GCOnly)
+ GCFlags |= cast<ConstantInt>(Val)->getZExtValue();
+ else if (KeyStr == SectionSpec)
+ Section = cast<MDString>(Val)->getString();
+ }
+
+ // The section is mandatory. If we don't have it, then we don't have image
+ // info information.
+ if (Section.empty()) return;
+
+ uint32_t Values[2] = { VersionVal, GCFlags };
+ Module *M = ModFlags->getParent();
+ Constant *Init = ConstantDataArray::get(M->getContext(), Values);
+ GlobalVariable *GV = new GlobalVariable(*M, Init->getType(), false,
+ GlobalValue::InternalLinkage, Init,
+ "\01L_OBJC_IMAGE_INFO");
+ GV->setSection(Section);
+
+ MCSymbol *GVSym = Mang->getSymbol(GV);
+ SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
+ const MCSection *TheSection = SectionForGlobal(GV, GVKind, Mang, TM);
+
+ Streamer.SwitchSection(TheSection);
+ Streamer.EmitLabel(GVSym);
+
+ Streamer.EmitIntValue(VersionVal, 4);
+ Streamer.EmitIntValue(GCFlags, 4);
+ Streamer.AddBlankLine();
+}
+
const MCSection *TargetLoweringObjectFileMachO::
getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler *Mang, const TargetMachine &TM) const {