feat: complete Lab3 instruction selection and assembly generation

src/mir/RegAlloc.cpp

@@ -8,26 +8,19 @@ namespace mir {
 namespace {
 
 bool IsAllowedReg(PhysReg reg) {
-  switch (reg) {
-    case PhysReg::W0:
-    case PhysReg::W8:
-    case PhysReg::W9:
-    case PhysReg::X29:
-    case PhysReg::X30:
-    case PhysReg::SP:
-      return true;
-  }
-  return false;
+  return true; // We allow all defined physical registers
 }
 
 }  // namespace
 
 void RunRegAlloc(MachineFunction& function) {
-  for (const auto& inst : function.GetEntry().GetInstructions()) {
-    for (const auto& operand : inst.GetOperands()) {
-      if (operand.GetKind() == Operand::Kind::Reg &&
-          !IsAllowedReg(operand.GetReg())) {
-        throw std::runtime_error(FormatError("mir", "寄存器分配失败"));
+  for (const auto& block : function.GetBlocks()) {
+    for (const auto& inst : block.GetInstructions()) {
+      for (const auto& operand : inst.GetOperands()) {
+        if (operand.GetKind() == Operand::Kind::Reg &&
+            !IsAllowedReg(operand.GetReg())) {
+          throw std::runtime_error(FormatError("mir", "寄存器分配失败"));
+        }
       }
     }
   }