Subzero: Refactor x86 register definitions to use the alias mechanism.

src/IceRegList.h

+//===- subzero/src/IceRegList.h - Register list macro defs  -----*- C++ -*-===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the REGLIST*() macros used in the IceInst*.def files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_SRC_ICEINSTREGLIST_H
+#define SUBZERO_SRC_ICEINSTREGLIST_H
+
+// REGLISTn is a family of macros that we use to define register aliasing.  "n"
+// indicates how many register aliases are being provided to the macro.  It
+// assumes the parameters are register names declared in the "ns"
+// namespace/class, but with the common "Reg_" prefix removed for brevity.
+#define REGLIST1(ns, r0)                                                       \
+  { ns::Reg_##r0 }
+#define REGLIST2(ns, r0, r1)                                                   \
+  { ns::Reg_##r0, ns::Reg_##r1 }
+#define REGLIST3(ns, r0, r1, r2)                                               \
+  { ns::Reg_##r0, ns::Reg_##r1, ns::Reg_##r2 }
+#define REGLIST4(ns, r0, r1, r2, r3)                                           \
+  { ns::Reg_##r0, ns::Reg_##r1, ns::Reg_##r2, ns::Reg_##r3 }
+#define REGLIST6(ns, r0, r1, r2, r3, r4, r5)                                   \
+  {                                                                            \
+    ns::Reg_##r0, ns::Reg_##r1, ns::Reg_##r2, ns::Reg_##r3, ns::Reg_##r4,      \
+        ns::Reg_##r5                                                           \
+  }
+
+#endif // SUBZERO_SRC_ICEINSTREGLIST_H