lib/Target/ARM/MCTargetDesc/ARMWinCOFFObjectWriter.cpp

   1 //===-- ARMWinCOFFObjectWriter.cpp - ARM Windows COFF Object Writer -- C++ -==//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "MCTargetDesc/ARMFixupKinds.h"
  11 #include "llvm/MC/MCFixup.h"
  12 #include "llvm/MC/MCValue.h"
  13 #include "llvm/MC/MCWinCOFFObjectWriter.h"
  14 #include "llvm/Support/COFF.h"
  15 #include "llvm/Support/Debug.h"
  16
  17 using namespace llvm;
  18
  19 namespace {
  20 class ARMWinCOFFObjectWriter : public MCWinCOFFObjectTargetWriter {
  21 public:
  22   ARMWinCOFFObjectWriter(bool Is64Bit)
  23     : MCWinCOFFObjectTargetWriter(COFF::IMAGE_FILE_MACHINE_ARMNT) {
  24     assert(!Is64Bit && "AArch64 support not yet implemented");
  25   }
  26   virtual ~ARMWinCOFFObjectWriter() = default;
  27
  28   unsigned getRelocType(const MCValue &Target, const MCFixup &Fixup,
  29                         bool IsCrossSection) const override;
  30 };
  31
  32 unsigned ARMWinCOFFObjectWriter::getRelocType(const MCValue &Target,
  33                                               const MCFixup &Fixup,
  34                                               bool IsCrossSection) const {
  35   assert(getMachine() == COFF::IMAGE_FILE_MACHINE_ARMNT &&
  36          "AArch64 support not yet implemented");
  37
  38   MCSymbolRefExpr::VariantKind Modifier =
  39     Target.isAbsolute() ? MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
  40
  41   switch (static_cast<unsigned>(Fixup.getKind())) {
  42   default: llvm_unreachable("unsupported relocation type");
  43   case FK_Data_4:
  44     switch (Modifier) {
  45     case MCSymbolRefExpr::VK_COFF_IMGREL32:
  46       return COFF::IMAGE_REL_ARM_ADDR32NB;
  47     case MCSymbolRefExpr::VK_SECREL:
  48       return COFF::IMAGE_REL_ARM_SECREL;
  49     default:
  50       return COFF::IMAGE_REL_ARM_ADDR32;
  51     }
  52   case ARM::fixup_t2_condbranch:
  53     return COFF::IMAGE_REL_ARM_BRANCH20T;
  54   case ARM::fixup_t2_uncondbranch:
  55     return COFF::IMAGE_REL_ARM_BRANCH24T;
  56   case ARM::fixup_arm_thumb_bl:
  57   case ARM::fixup_arm_thumb_blx:
  58     return COFF::IMAGE_REL_ARM_BLX23T;
  59   case ARM::fixup_t2_movw_lo16:
  60     return COFF::IMAGE_REL_ARM_MOV32T;
  61   case ARM::fixup_t2_movt_hi16:
  62     llvm_unreachable("High-word for pair-wise relocations are contiguously "
  63                      "addressed as an IMAGE_REL_ARM_MOV32T relocation");
  64   }
  65 }
  66 }
  67
  68 namespace llvm {
  69 MCObjectWriter *createARMWinCOFFObjectWriter(raw_ostream &OS, bool Is64Bit) {
  70   MCWinCOFFObjectTargetWriter *MOTW = new ARMWinCOFFObjectWriter(Is64Bit);
  71   return createWinCOFFObjectWriter(MOTW, OS);
  72 }
  73 }
  74