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

src/IceAssemblerARM32.h

Index: src/IceAssemblerARM32.h
diff --git a/src/IceAssemblerARM32.h b/src/IceAssemblerARM32.h
index 20b4e67da28ee3f7596688728a9378cdf3a6dec5..fffbd97fe2c9157c88c0dcb9cdda7d720aec2938 100644
--- a/src/IceAssemblerARM32.h
+++ b/src/IceAssemblerARM32.h
@@ -43,8 +43,8 @@ class AssemblerARM32 : public Assembler {
   AssemblerARM32 &operator=(const AssemblerARM32 &) = delete;
 
 public:
-  explicit AssemblerARM32(GlobalContext *Ctx, bool use_far_branches = false)
-      : Assembler(Asm_ARM32, Ctx) {
+  explicit AssemblerARM32(bool use_far_branches = false)
+      : Assembler(Asm_ARM32) {
     // TODO(kschimpf): Add mode if needed when branches are handled.
     (void)use_far_branches;
   }