1 files changed, 141 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/X86/MCTargetDesc/X86ELFRelocationInfo.cpp b/contrib/llvm/lib/Target/X86/MCTargetDesc/X86ELFRelocationInfo.cpp
new file mode 100644
index 0000000..ddb764f
--- /dev/null
+++ b/contrib/llvm/lib/Target/X86/MCTargetDesc/X86ELFRelocationInfo.cpp
@@ -0,0 +1,141 @@
+//===-- X86ELFRelocationInfo.cpp ----------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/X86MCTargetDesc.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCRelocationInfo.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Support/ELF.h"
+
+using namespace llvm;
+using namespace object;
+using namespace ELF;
+
+namespace {
+class X86_64ELFRelocationInfo : public MCRelocationInfo {
+public:
+  X86_64ELFRelocationInfo(MCContext &Ctx) : MCRelocationInfo(Ctx) {}
+
+  const MCExpr *createExprForRelocation(RelocationRef Rel) override {
+    uint64_t RelType = Rel.getType();
+    elf_symbol_iterator SymI = Rel.getSymbol();
+
+    ErrorOr<StringRef> SymNameOrErr = SymI->getName();
+    if (std::error_code EC = SymNameOrErr.getError())
+      report_fatal_error(EC.message());
+    StringRef SymName = *SymNameOrErr;
+
+    ErrorOr<uint64_t> SymAddr = SymI->getAddress();
+    if (std::error_code EC = SymAddr.getError())
+      report_fatal_error(EC.message());
+    uint64_t SymSize = SymI->getSize();
+    int64_t Addend = *ELFRelocationRef(Rel).getAddend();
+
+    MCSymbol *Sym = Ctx.getOrCreateSymbol(SymName);
+    // FIXME: check that the value is actually the same.
+    if (!Sym->isVariable())
+      Sym->setVariableValue(MCConstantExpr::create(*SymAddr, Ctx));
+
+    const MCExpr *Expr = nullptr;
+    // If hasAddend is true, then we need to add Addend (r_addend) to Expr.
+    bool hasAddend = false;
+
+    // The AMD64 SysV ABI says:
+    // A: the addend used to compute the value of the relocatable field.
+    // B: the base address at which a shared object has been loaded into memory
+    //    during execution. Generally, a shared object is built with a 0 base
+    //    virtual address, but the execution address will be different.
+    // G: the offset into the global offset table at which the relocation
+    //    entry's symbol will reside during execution.
+    // GOT: the address of the global offset table.
+    // L: the place (section offset or address) of the Procedure Linkage Table
+    //    entry for a symbol.
+    // P: the place (section offset or address) of the storage unit being
+    //    relocated (computed using r_offset).
+    // S: the value of the symbol whose index resides in the relocation entry.
+    // Z: the size of the symbol whose index resides in the relocation entry.
+
+    switch(RelType) {
+    case R_X86_64_NONE:
+    case R_X86_64_COPY:
+      // none
+      break;
+    case R_X86_64_64:
+    case R_X86_64_16:
+    case R_X86_64_8:
+      // S + A
+    case R_X86_64_32:
+    case R_X86_64_32S:
+      // S + A (We don't care about the result not fitting in 32 bits.)
+    case R_X86_64_PC32:
+    case R_X86_64_PC16:
+    case R_X86_64_PC8:
+    case R_X86_64_PC64:
+      // S + A - P (P/pcrel is implicit)
+      hasAddend = true;
+      Expr = MCSymbolRefExpr::create(Sym, Ctx);
+      break;
+    case R_X86_64_GOT32:
+    case R_X86_64_GOT64:
+    case R_X86_64_GOTPC32:
+    case R_X86_64_GOTPC64:
+    case R_X86_64_GOTPLT64:
+      // G + A
+      hasAddend = true;
+      Expr = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOT, Ctx);
+      break;
+    case R_X86_64_PLT32:
+      // L + A - P -> S@PLT + A
+      hasAddend = true;
+      Expr = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_PLT, Ctx);
+      break;
+    case R_X86_64_GLOB_DAT:
+    case R_X86_64_JUMP_SLOT:
+      // S
+      Expr = MCSymbolRefExpr::create(Sym, Ctx);
+      break;
+    case R_X86_64_GOTPCREL:
+    case R_X86_64_GOTPCREL64:
+      // G + GOT + A - P -> S@GOTPCREL + A
+      hasAddend = true;
+      Expr = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, Ctx);
+      break;
+    case R_X86_64_GOTOFF64:
+      // S + A - GOT
+      Expr = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTOFF, Ctx);
+      break;
+    case R_X86_64_PLTOFF64:
+      // L + A - GOT
+      break;
+    case R_X86_64_SIZE32:
+    case R_X86_64_SIZE64:
+      // Z + A
+      Expr = MCConstantExpr::create(SymSize, Ctx);
+      break;
+    default:
+      Expr = MCSymbolRefExpr::create(Sym, Ctx);
+      break;
+    }
+    if (Expr && hasAddend && Addend != 0)
+      Expr = MCBinaryExpr::createAdd(Expr,
+                                     MCConstantExpr::create(Addend, Ctx),
+                                     Ctx);
+    return Expr;
+  }
+};
+} // End unnamed namespace
+
+/// createX86ELFRelocationInfo - Construct an X86 Mach-O RelocationInfo.
+MCRelocationInfo *llvm::createX86_64ELFRelocationInfo(MCContext &Ctx) {
+  // We only handle x86-64 for now.
+  return new X86_64ELFRelocationInfo(Ctx);
+}