X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FX86%2FX86TargetObjectFile.cpp;h=b62cc257697d186cf98b7bbf7a6e55cb2b55c1b8;hb=eda7f44b27690d050bae738552f9e1f08e72133f;hp=709fc972560d9a8a2b0464454c3411fe113dab66;hpb=9f20a4c6cea7315af0e01ac58e5fdbb9c0eb8006;p=oota-llvm.git

diff --git a/lib/Target/X86/X86TargetObjectFile.cpp b/lib/Target/X86/X86TargetObjectFile.cpp
index 709fc972560..b62cc257697 100644
--- a/lib/Target/X86/X86TargetObjectFile.cpp
+++ b/lib/Target/X86/X86TargetObjectFile.cpp
@@ -9,37 +9,39 @@
 
 #include "X86TargetObjectFile.h"
 #include "llvm/IR/Mangler.h"
+#include "llvm/IR/Operator.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCSectionELF.h"
 #include "llvm/Support/Dwarf.h"
+#include "llvm/Target/TargetLowering.h"
 
 using namespace llvm;
 using namespace dwarf;
 
-const MCExpr *X86_64MachoTargetObjectFile::
-getTTypeGlobalReference(const GlobalValue *GV, Mangler *Mang,
-                        MachineModuleInfo *MMI, unsigned Encoding,
-                        MCStreamer &Streamer) const {
+const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
+    const GlobalValue *GV, unsigned Encoding, Mangler &Mang,
+    const TargetMachine &TM, MachineModuleInfo *MMI,
+    MCStreamer &Streamer) const {
 
   // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
   // is an indirect pc-relative reference.
   if (Encoding & (DW_EH_PE_indirect | DW_EH_PE_pcrel)) {
-    const MCSymbol *Sym = getSymbol(*Mang, GV);
+    const MCSymbol *Sym = TM.getSymbol(GV, Mang);
     const MCExpr *Res =
       MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
     const MCExpr *Four = MCConstantExpr::Create(4, getContext());
     return MCBinaryExpr::CreateAdd(Res, Four, getContext());
   }
 
-  return TargetLoweringObjectFileMachO::
-    getTTypeGlobalReference(GV, Mang, MMI, Encoding, Streamer);
+  return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
+      GV, Encoding, Mang, TM, MMI, Streamer);
 }
 
-MCSymbol *X86_64MachoTargetObjectFile::
-getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
-                        MachineModuleInfo *MMI) const {
-  return getSymbol(*Mang, GV);
+MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol(
+    const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM,
+    MachineModuleInfo *MMI) const {
+  return TM.getSymbol(GV, Mang);
 }
 
 void
@@ -53,3 +55,54 @@ X86LinuxTargetObjectFile::getDebugThreadLocalSymbol(
     const MCSymbol *Sym) const {
   return MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
 }
+
+const MCExpr *X86WindowsTargetObjectFile::getExecutableRelativeSymbol(
+    const ConstantExpr *CE, Mangler &Mang, const TargetMachine &TM) const {
+  // We are looking for the difference of two symbols, need a subtraction
+  // operation.
+  const SubOperator *Sub = dyn_cast<SubOperator>(CE);
+  if (!Sub)
+    return nullptr;
+
+  // Symbols must first be numbers before we can subtract them, we need to see a
+  // ptrtoint on both subtraction operands.
+  const PtrToIntOperator *SubLHS =
+      dyn_cast<PtrToIntOperator>(Sub->getOperand(0));
+  const PtrToIntOperator *SubRHS =
+      dyn_cast<PtrToIntOperator>(Sub->getOperand(1));
+  if (!SubLHS || !SubRHS)
+    return nullptr;
+
+  // Our symbols should exist in address space zero, cowardly no-op if
+  // otherwise.
+  if (SubLHS->getPointerAddressSpace() != 0 ||
+      SubRHS->getPointerAddressSpace() != 0)
+    return nullptr;
+
+  // Both ptrtoint instructions must wrap global variables:
+  // - Only global variables are eligible for image relative relocations.
+  // - The subtrahend refers to the special symbol __ImageBase, a global.
+  const GlobalVariable *GVLHS =
+      dyn_cast<GlobalVariable>(SubLHS->getPointerOperand());
+  const GlobalVariable *GVRHS =
+      dyn_cast<GlobalVariable>(SubRHS->getPointerOperand());
+  if (!GVLHS || !GVRHS)
+    return nullptr;
+
+  // We expect __ImageBase to be a global variable without a section, externally
+  // defined.
+  //
+  // It should look something like this: @__ImageBase = external constant i8
+  if (GVRHS->isThreadLocal() || GVRHS->getName() != "__ImageBase" ||
+      !GVRHS->hasExternalLinkage() || GVRHS->hasInitializer() ||
+      GVRHS->hasSection())
+    return nullptr;
+
+  // An image-relative, thread-local, symbol makes no sense.
+  if (GVLHS->isThreadLocal())
+    return nullptr;
+
+  return MCSymbolRefExpr::Create(TM.getSymbol(GVLHS, Mang),
+                                 MCSymbolRefExpr::VK_COFF_IMGREL32,
+                                 getContext());
+}