lib/Target/X86/MCTargetDesc/X86MCExpr.h

   1 //=--- X86MCExpr.h - X86 specific MC expression classes ---*- C++ -*-=//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file describes X86-specific MCExprs, i.e, registers used for
  10 // extended variable assignments.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_LIB_TARGET_X86_MCTARGETDESC_X86MCEXPR_H
  15 #define LLVM_LIB_TARGET_X86_MCTARGETDESC_X86MCEXPR_H
  16
  17 #include "X86ATTInstPrinter.h"
  18 #include "llvm/MC/MCAsmInfo.h"
  19 #include "llvm/MC/MCContext.h"
  20 #include "llvm/MC/MCExpr.h"
  21 #include "llvm/Support/ErrorHandling.h"
  22
  23 namespace llvm {
  24
  25 class X86MCExpr : public MCTargetExpr {
  26
  27 private:
  28   const int64_t RegNo; // All
  29
  30   explicit X86MCExpr(int64_t R) : RegNo(R) {}
  31
  32 public:
  33   /// @name Construction
  34   /// @{
  35
  36   static const X86MCExpr *create(int64_t RegNo, MCContext &Ctx) {
  37     return new (Ctx) X86MCExpr(RegNo);
  38   }
  39
  40   /// @}
  41   /// @name Accessors
  42   /// @{
  43
  44   /// getSubExpr - Get the child of this expression.
  45   int64_t getRegNo() const { return RegNo; }
  46
  47   /// @}
  48
  49   void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override {
  50     if (!MAI || MAI->getAssemblerDialect() == 0)
  51       OS << '%';
  52     OS << X86ATTInstPrinter::getRegisterName(RegNo);
  53   }
  54
  55   bool evaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout,
  56                                  const MCFixup *Fixup) const override {
  57     return false;
  58   }
  59   // Register values should be inlined as they are not valid .set expressions.
  60   bool inlineAssignedExpr() const override { return true; }
  61   bool isEqualTo(const MCExpr *X) const override {
  62     if (auto *E = dyn_cast<X86MCExpr>(X))
  63       return getRegNo() == E->getRegNo();
  64     return false;
  65   }
  66   void visitUsedExpr(MCStreamer &Streamer) const override{};
  67   MCFragment *findAssociatedFragment() const override { return nullptr; }
  68
  69   // There are no TLS X86MCExprs at the moment.
  70   void fixELFSymbolsInTLSFixups(MCAssembler &Asm) const override {}
  71
  72   static bool classof(const MCExpr *E) {
  73     return E->getKind() == MCExpr::Target;
  74   }
  75 };
  76
  77 } // end namespace llvm
  78
  79 #endif