MC/Mach-O: Mark absolute variable's appropriately, and add Mach-O support for

writing them.
 - <rdar://problem/7885351> integrated assembler broken for i386 objc code

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103112 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 6 insertions, 4 deletions

diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index 1d231bb..22b1a37 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -239,7 +239,6 @@ void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
   EmitEOL();
 
   // FIXME: Lift context changes into super class.
-  // FIXME: Set associated section.
   Symbol->setVariableValue(Value);
 }
 
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index b4bd557..5ca3194 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -193,7 +193,6 @@ void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
 
 void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
   // FIXME: Lift context changes into super class.
-  // FIXME: Set associated section.
   Symbol->setVariableValue(AddValueSymbols(Value));
 }
 
diff --git a/lib/MC/MCSymbol.cpp b/lib/MC/MCSymbol.cpp
index 82d72a3..07751f7 100644
--- a/lib/MC/MCSymbol.cpp
+++ b/lib/MC/MCSymbol.cpp
@@ -44,6 +44,10 @@ void MCSymbol::setVariableValue(const MCExpr *Value) {
   assert((isUndefined() || (isAbsolute() && isa<MCConstantExpr>(Value))) &&
          "Invalid redefinition!");
   this->Value = Value;
+
+  // Mark the variable as absolute as appropriate.
+  if (isa<MCConstantExpr>(Value))
+    setAbsolute();
 }
 
 void MCSymbol::print(raw_ostream &OS) const {
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index f4aef96..bb8eb10 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -404,7 +404,7 @@ public:
     // Compute the symbol address.
     if (Symbol.isDefined()) {
       if (Symbol.isAbsolute()) {
-        llvm_unreachable("FIXME: Not yet implemented!");
+        Address = cast<MCConstantExpr>(Symbol.getVariableValue())->getValue();
       } else {
         Address = Layout.getSymbolAddress(&Data);
       }
@@ -552,7 +552,7 @@ public:
       // possible. This seems to be done because the debugger doesn't fully
       // understand x86_64 relocation entries, and expects to find values that
       // have already been fixed up.
-      if (Symbol->isDefined()) {
+      if (Symbol->isInSection()) {
         const MCSectionMachO &Section = static_cast<const MCSectionMachO&>(
           Fragment->getParent()->getSection());
         if (Section.hasAttribute(MCSectionMachO::S_ATTR_DEBUG))