make vscale symbolic

Author: zhengyangliuTT

ir/type.cpp

@@ -1090,6 +1090,11 @@ void ArrayType::print(ostream &os) const {
 }
 
 
+expr VectorType::vscale() const {
+  return defined ? expr::mkUInt(vscale_value, var_vector_elements) :
+                   var("vscale", var_vector_elements);
+}
+
 VectorType::VectorType(string &&name, unsigned elems, Type &elTy, bool scal)
   : AggregateType(std::move(name), false), scalable(scal), min_elements(elems) {
   assert(elems != 0);

ir/type.h

@@ -338,9 +338,10 @@ class ArrayType final : public AggregateType {
 class VectorType final : public AggregateType {
 private:
   bool scalable = false;
-  unsigned min_elements;
+  unsigned min_elements, vscale_value;
 
 public:
+  smt::expr vscale() const;
   VectorType(std::string &&name) : AggregateType(std::move(name)) {}
   VectorType(std::string &&name, unsigned elems, Type &elemTy, bool scalable);