Adds the x86-64 assembler.

src/IceTargetLoweringX8664Traits.h

+//===- subzero/src/IceTargetLoweringX8664Traits.h - x86-64 traits -*- C++ -*-=//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file declares the X8664 Target Lowering Traits.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_SRC_ICETARGETLOWERINGX8664TRAITS_H
+#define SUBZERO_SRC_ICETARGETLOWERINGX8664TRAITS_H
+
+#include "IceAssembler.h"
+#include "IceConditionCodesX8664.h"
+#include "IceDefs.h"
+#include "IceInst.h"
+#include "IceInstX8664.def"
+#include "IceOperand.h"
+#include "IceRegistersX8664.h"
+#include "IceTargetLowering.h"
+
+namespace Ice {
+
+class TargetX8664;
+
+namespace X8664 {
+class AssemblerX8664;
+} // end of namespace X8664
+
+namespace X86Internal {
+
+template <class Machine> struct Insts;
+template <class Machine> struct MachineTraits;
+
+template <> struct MachineTraits<TargetX8664> {
+  //----------------------------------------------------------------------------
+  //     ______  ______  __    __
+  //    /\  __ \/\  ___\/\ "-./  \
+  //    \ \  __ \ \___  \ \ \-./\ \
+  //     \ \_\ \_\/\_____\ \_\ \ \_\
+  //      \/_/\/_/\/_____/\/_/  \/_/
+  //
+  //----------------------------------------------------------------------------
+  static constexpr bool Is64Bit = true;
+  static constexpr bool HasPopa = false;
+  static constexpr bool HasPusha = false;
+  static constexpr bool UsesX87 = false;
+  static constexpr ::Ice::RegX8664::GPRRegister Last8BitGPR =
+      ::Ice::RegX8664::GPRRegister::Encoded_Reg_r15d;
+
+  enum ScaleFactor { TIMES_1 = 0, TIMES_2 = 1, TIMES_4 = 2, TIMES_8 = 3 };
+
+  using GPRRegister = ::Ice::RegX8664::GPRRegister;
+  using XmmRegister = ::Ice::RegX8664::XmmRegister;
+  using ByteRegister = ::Ice::RegX8664::ByteRegister;
+
+  using Cond = ::Ice::CondX8664;
+
+  using RegisterSet = ::Ice::RegX8664;
+  static const GPRRegister Encoded_Reg_Accumulator = RegX8664::Encoded_Reg_eax;
+  static const GPRRegister Encoded_Reg_Counter = RegX8664::Encoded_Reg_ecx;
+  static const FixupKind PcRelFixup = llvm::ELF::R_386_PC32; // TODO(jpp): ???
+
+  class Operand {
+  public:
+    enum RexBits {
+      RexNone = 0x00,
+      RexBase = 0x40,
+      RexW = RexBase | (1 << 3),
+      RexR = RexBase | (1 << 2),
+      RexX = RexBase | (1 << 1),
+      RexB = RexBase | (1 << 0),
+    };
+
+    Operand(const Operand &other)
+        : fixup_(other.fixup_), rex_(other.rex_), length_(other.length_) {
+      memmove(&encoding_[0], &other.encoding_[0], other.length_);
+    }
+
+    Operand &operator=(const Operand &other) {
+      length_ = other.length_;
+      fixup_ = other.fixup_;
+      rex_ = other.rex_;
+      memmove(&encoding_[0], &other.encoding_[0], other.length_);
+      return *this;
+    }
+
+    uint8_t mod() const { return (encoding_at(0) >> 6) & 3; }
+
+    uint8_t rexX() const { return (rex_ & RexX) != RexX ? RexNone : RexX; }
+    uint8_t rexB() const { return (rex_ & RexB) != RexB ? RexNone : RexB; }
+
+    GPRRegister rm() const {
+      return static_cast<GPRRegister>((rexB() != 0 ? 0x08 : 0) |
+                                      (encoding_at(0) & 7));
+    }
+
+    ScaleFactor scale() const {
+      return static_cast<ScaleFactor>((encoding_at(1) >> 6) & 3);
+    }
+
+    GPRRegister index() const {
+      return static_cast<GPRRegister>((rexX() != 0 ? 0x08 : 0) |
+                                      ((encoding_at(1) >> 3) & 7));
+    }
+
+    GPRRegister base() const {
+      return static_cast<GPRRegister>((rexB() != 0 ? 0x08 : 0) |
+                                      (encoding_at(1) & 7));
+    }
+
+    int8_t disp8() const {
+      assert(length_ >= 2);
+      return static_cast<int8_t>(encoding_[length_ - 1]);
+    }
+
+    int32_t disp32() const {
+      assert(length_ >= 5);
+      return bit_copy<int32_t>(encoding_[length_ - 4]);
+    }
+
+    AssemblerFixup *fixup() const { return fixup_; }
+
+  protected:
+    Operand() : fixup_(nullptr), length_(0) {} // Needed by subclass Address.
+
+    void SetModRM(int mod, GPRRegister rm) {
+      assert((mod & ~3) == 0);
+      encoding_[0] = (mod << 6) | (rm & 0x07);
+      rex_ = (rm & 0x08) ? RexB : RexNone;
+      length_ = 1;
+    }
+
+    void SetSIB(ScaleFactor scale, GPRRegister index, GPRRegister base) {
+      assert(length_ == 1);
+      assert((scale & ~3) == 0);
+      encoding_[1] = (scale << 6) | ((index & 0x07) << 3) | (base & 0x07);
+      rex_ =
+          ((base & 0x08) ? RexB : RexNone) | ((index & 0x08) ? RexX : RexNone);
+      length_ = 2;
+    }
+
+    void SetDisp8(int8_t disp) {
+      assert(length_ == 1 || length_ == 2);
+      encoding_[length_++] = static_cast<uint8_t>(disp);
+    }
+
+    void SetDisp32(int32_t disp) {
+      assert(length_ == 1 || length_ == 2);
+      intptr_t disp_size = sizeof(disp);
+      memmove(&encoding_[length_], &disp, disp_size);
+      length_ += disp_size;
+    }
+
+    void SetFixup(AssemblerFixup *fixup) { fixup_ = fixup; }
+
+  private:
+    AssemblerFixup *fixup_;
+    uint8_t rex_ = 0;
+    uint8_t encoding_[6];
+    uint8_t length_;
+
+    explicit Operand(GPRRegister reg) : fixup_(nullptr) { SetModRM(3, reg); }
+
+    /// Get the operand encoding byte at the given index.
+    uint8_t encoding_at(intptr_t index) const {
+      assert(index >= 0 && index < length_);
+      return encoding_[index];
+    }
+
+    /// Returns whether or not this operand is really the given register in
+    /// disguise. Used from the assembler to generate better encodings.
+    bool IsRegister(GPRRegister reg) const {
+      return ((encoding_[0] & 0xF8) ==
+              0xC0) // Addressing mode is register only.
+             &&
+             (rm() == reg); // Register codes match.
+    }
+
+    template <class> friend class AssemblerX86Base;
+  };
+
+  class Address : public Operand {
+    Address() = delete;
+
+  public:
+    Address(const Address &other) : Operand(other) {}
+
+    Address &operator=(const Address &other) {
+      Operand::operator=(other);
+      return *this;
+    }
+
+    Address(GPRRegister base, int32_t disp) {
+      if (disp == 0 && (base & 7) != RegX8664::Encoded_Reg_ebp) {
+        SetModRM(0, base);
+        if ((base & 7) == RegX8664::Encoded_Reg_esp)
+          SetSIB(TIMES_1, RegX8664::Encoded_Reg_esp, base);
+      } else if (Utils::IsInt(8, disp)) {
+        SetModRM(1, base);
+        if ((base & 7) == RegX8664::Encoded_Reg_esp)
+          SetSIB(TIMES_1, RegX8664::Encoded_Reg_esp, base);
+        SetDisp8(disp);
+      } else {
+        SetModRM(2, base);
+        if ((base & 7) == RegX8664::Encoded_Reg_esp)
+          SetSIB(TIMES_1, RegX8664::Encoded_Reg_esp, base);
+        SetDisp32(disp);
+      }
+    }
+
+    Address(GPRRegister index, ScaleFactor scale, int32_t disp) {
+      assert(index != RegX8664::Encoded_Reg_esp); // Illegal addressing mode.
+      SetModRM(0, RegX8664::Encoded_Reg_esp);
+      SetSIB(scale, index, RegX8664::Encoded_Reg_ebp);
+      SetDisp32(disp);
+    }
+
+    Address(GPRRegister base, GPRRegister index, ScaleFactor scale,
+            int32_t disp) {
+      assert(index != RegX8664::Encoded_Reg_esp); // Illegal addressing mode.
+      if (disp == 0 && (base & 7) != RegX8664::Encoded_Reg_ebp) {
+        SetModRM(0, RegX8664::Encoded_Reg_esp);
+        SetSIB(scale, index, base);
+      } else if (Utils::IsInt(8, disp)) {
+        SetModRM(1, RegX8664::Encoded_Reg_esp);
+        SetSIB(scale, index, base);
+        SetDisp8(disp);
+      } else {
+        SetModRM(2, RegX8664::Encoded_Reg_esp);
+        SetSIB(scale, index, base);
+        SetDisp32(disp);
+      }
+    }
+
+    // PcRelTag is a special tag for requesting rip-relative addressing in
+    // X86-64.
+    // TODO(jpp): this is bogus. remove.
+    enum AbsoluteTag { ABSOLUTE };
+
+    Address(AbsoluteTag, const uintptr_t Addr) {
+      SetModRM(0, RegX8664::Encoded_Reg_ebp);
+      SetDisp32(Addr);
+    }
+
+    // TODO(jpp): remove this.
+    static Address Absolute(const uintptr_t Addr) {
+      return Address(ABSOLUTE, Addr);
+    }
+
+    Address(AbsoluteTag, RelocOffsetT Offset, AssemblerFixup *Fixup) {
+      SetModRM(0, RegX8664::Encoded_Reg_ebp);
+      // Use the Offset in the displacement for now. If we decide to process
+      // fixups later, we'll need to patch up the emitted displacement.
+      SetDisp32(Offset);
+      SetFixup(Fixup);
+    }
+
+    // TODO(jpp): remove this.
+    static Address Absolute(RelocOffsetT Offset, AssemblerFixup *Fixup) {
+      return Address(ABSOLUTE, Offset, Fixup);
+    }
+
+    static Address ofConstPool(Assembler *Asm, const Constant *Imm) {
+      // TODO(jpp): ???
+      AssemblerFixup *Fixup = Asm->createFixup(llvm::ELF::R_386_32, Imm);
+      const RelocOffsetT Offset = 0;
+      return Address(ABSOLUTE, Offset, Fixup);
+    }
+  };
+
+  //----------------------------------------------------------------------------
+  //     __      ______  __     __  ______  ______  __  __   __  ______
+  //    /\ \    /\  __ \/\ \  _ \ \/\  ___\/\  == \/\ \/\ "-.\ \/\  ___\
+  //    \ \ \___\ \ \/\ \ \ \/ ".\ \ \  __\\ \  __<\ \ \ \ \-.  \ \ \__ \
+  //     \ \_____\ \_____\ \__/".~\_\ \_____\ \_\ \_\ \_\ \_\\"\_\ \_____\
+  //      \/_____/\/_____/\/_/   \/_/\/_____/\/_/ /_/\/_/\/_/ \/_/\/_____/
+  //
+  //----------------------------------------------------------------------------
+  using Assembler = X8664::AssemblerX8664;
+};
+
+} // end of namespace X86Internal
+
+namespace X8664 {
+using Traits = ::Ice::X86Internal::MachineTraits<TargetX8664>;
+} // end of namespace X8664
+
+} // end of namespace Ice
+
+#endif // SUBZERO_SRC_ICETARGETLOWERINGX8664TRAITS_H