diff --git a/spec/lib/rex/arch/x86_spec.rb b/spec/lib/rex/arch/x86_spec.rb
index ac40e94..edac06d 100644
--- a/spec/lib/rex/arch/x86_spec.rb
+++ b/spec/lib/rex/arch/x86_spec.rb
@@ -1039,4 +1039,45 @@
     end
   end
 
+  describe ".register_names_to_ids" do
+    subject { described_class.register_names_to_ids(registers) }
+
+    context "when registers are not provided" do
+      let(:registers) { nil }
+
+      it "returns an empty Array" do
+        is_expected.to be_an Array
+        is_expected.to be_empty
+      end
+    end
+
+    context "when registers are invalid" do
+      let(:registers) { "not-a-register" }
+
+      it "raises an error" do
+        expect { subject }.to raise_error(NameError)
+      end
+    end
+
+    context "when registers are valid" do
+      let(:registers) { " eax, ecx, edx, ebx, esp, ebp, esi, edi " }
+
+      it "returns an Array" do
+        is_expected.to be_an Array
+      end
+
+      it "returns an Integer for each register" do
+        expect(subject.length).to eq(8)
+        expect(subject[0]).to be_an Integer
+        expect(subject[1]).to be_an Integer
+        expect(subject[2]).to be_an Integer
+        expect(subject[3]).to be_an Integer
+        expect(subject[4]).to be_an Integer
+        expect(subject[5]).to be_an Integer
+        expect(subject[6]).to be_an Integer
+        expect(subject[7]).to be_an Integer
+      end
+    end
+  end
+
 end
diff --git a/spec/lib/rex/arch_spec.rb b/spec/lib/rex/arch_spec.rb
index cccf235..461e7eb 100644
--- a/spec/lib/rex/arch_spec.rb
+++ b/spec/lib/rex/arch_spec.rb
@@ -118,6 +118,14 @@
       end
     end
 
+    context "when arch is ARCH_PPCE500V2" do
+      let(:arch) { Rex::Arch::ARCH_PPCE500V2 }
+      let(:addr) { 0x41424344 }
+      it "packs addr as 32-bit unsigned, big-endian" do
+        is_expected.to eq("ABCD")
+      end
+    end
+
     context "when arch is ARCH_SPARC" do
       let(:arch) { Rex::Arch::ARCH_SPARC }
       let(:addr) { 0x41424344 }
@@ -230,13 +238,17 @@
       {
         Rex::Arch::ARCH_X86 => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_X86_64 => Rex::Arch::ENDIAN_LITTLE,
+        Rex::Arch::ARCH_X64 => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_MIPS => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_MIPSLE => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_MIPSBE => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_MIPS64 => Rex::Arch::ENDIAN_BIG,
+        Rex::Arch::ARCH_MIPS64LE => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_PPC => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_PPC64LE => Rex::Arch::ENDIAN_LITTLE,
+        Rex::Arch::ARCH_PPCE500V2 => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_SPARC => Rex::Arch::ENDIAN_BIG,
+        Rex::Arch::ARCH_SPARC64 => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_ARMLE => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_ARMBE => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_AARCH64 => Rex::Arch::ENDIAN_LITTLE,
@@ -245,6 +257,7 @@
         Rex::Arch::ARCH_RISCV64BE => Rex::Arch::ENDIAN_BIG,
         Rex::Arch::ARCH_RISCV64LE => Rex::Arch::ENDIAN_LITTLE,
         Rex::Arch::ARCH_LOONGARCH64 => Rex::Arch::ENDIAN_LITTLE,
+        Rex::Arch::ARCH_ZARCH => Rex::Arch::ENDIAN_BIG,
       }
     end
     subject { described_class.endian(arch) }