Enhance address mode recovery

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
@@ skipping 183 matching lines @@
     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);
+    Address(GPRRegister Base, int32_t Disp, AssemblerFixup *Fixup) {
+      if (Fixup == nullptr && 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 (Fixup == nullptr && 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);
+        SetModRM(2, Base);
+        if ((Base & 7) == RegX8664::Encoded_Reg_esp)
+          SetSIB(TIMES_1, RegX8664::Encoded_Reg_esp, Base);
+        SetDisp32(Disp);
+        if (Fixup)
+          SetFixup(Fixup);
       }
     }
 
-    Address(GPRRegister index, ScaleFactor scale, int32_t disp) {
-      assert(index != RegX8664::Encoded_Reg_esp); // Illegal addressing mode.
+    Address(GPRRegister Index, ScaleFactor Scale, int32_t Disp,
+            AssemblerFixup *Fixup) {
+      assert(Index != RegX8664::Encoded_Reg_esp); // Illegal addressing mode.
       SetModRM(0, RegX8664::Encoded_Reg_esp);
-      SetSIB(scale, index, RegX8664::Encoded_Reg_ebp);
-      SetDisp32(disp);
+      SetSIB(Scale, Index, RegX8664::Encoded_Reg_ebp);
+      SetDisp32(Disp);
+      if (Fixup)
+        SetFixup(Fixup);
     }
 
-    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) {
+    Address(GPRRegister Base, GPRRegister Index, ScaleFactor Scale,
+            int32_t Disp, AssemblerFixup *Fixup) {
+      assert(Index != RegX8664::Encoded_Reg_esp); // Illegal addressing mode.
+      if (Fixup == nullptr && Disp == 0 &&
+          (Base & 7) != RegX8664::Encoded_Reg_ebp) {
         SetModRM(0, RegX8664::Encoded_Reg_esp);
-        SetSIB(scale, index, base);
-      } else if (Utils::IsInt(8, disp)) {
+        SetSIB(Scale, Index, Base);
+      } else if (Fixup == nullptr && Utils::IsInt(8, Disp)) {
         SetModRM(1, RegX8664::Encoded_Reg_esp);
-        SetSIB(scale, index, base);
-        SetDisp8(disp);
+        SetSIB(Scale, Index, Base);
+        SetDisp8(Disp);
       } else {
         SetModRM(2, RegX8664::Encoded_Reg_esp);
-        SetSIB(scale, index, base);
-        SetDisp32(disp);
+        SetSIB(Scale, Index, Base);
+        SetDisp32(Disp);
+        if (Fixup)
+          SetFixup(Fixup);
       }
     }
 
-    // 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) {
+    /// Generate a RIP-relative address expression on x86-64.
+    Address(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);
+      if (Fixup)
+        SetFixup(Fixup);
     }
 
     static Address ofConstPool(Assembler *Asm, const Constant *Imm) {
       // TODO(jpp): ???
       AssemblerFixup *Fixup = Asm->createFixup(RelFixup, Imm);
       const RelocOffsetT Offset = 4;
-      return Address(ABSOLUTE, Offset, Fixup);
+      return Address(Offset, Fixup);
     }
   };
 
   //----------------------------------------------------------------------------
   //     __      ______  __     __  ______  ______  __  __   __  ______
   //    /\ \    /\  __ \/\ \  _ \ \/\  ___\/\  == \/\ \/\ "-.\ \/\  ___\
   //    \ \ \___\ \ \/\ \ \ \/ ".\ \ \  __\\ \  __<\ \ \ \ \-.  \ \ \__ \
   //     \ \_____\ \_____\ \__/".~\_\ \_____\ \_\ \_\ \_\ \_\\"\_\ \_____\
   //      \/_____/\/_____/\/_/   \/_/\/_____/\/_/ /_/\/_/\/_/ \/_/\/_____/
   //
@@ skipping 459 matching lines @@
 
 } // 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