AIA: add null pointer check to VS get_csrmap(1)

Author: i2h2

riscv/csr_init.cc

@@ -498,9 +498,12 @@ void state_t::csr_init(processor_t* const proc, reg_t max_isa)
     if (proc->extension_enabled_const(EXT_SSAIA)) {
       auto aia_vsireg = std::make_shared<aia_ireg_proxy_csr_t>(proc, CSR_VSIREG, vsiselect);
       // csrmaps of vs files are the same as vgein = 1
-      for (auto &csr : *aia_vsireg->get_csrmap(1))
-        vsireg->add_ireg_proxy(csr.first, aia_vsireg);
-      add_ireg_proxy(vsireg, aia_vsireg);
+      auto *csrmap = aia_vsireg->get_csrmap(1);
+      if (csrmap) {
+        for (auto &csr : *csrmap)
+          vsireg->add_ireg_proxy(csr.first, aia_vsireg);
+        add_ireg_proxy(vsireg, aia_vsireg);
+      }
 
       auto aia_sireg = std::make_shared<aia_ireg_proxy_csr_t>(proc, CSR_SIREG, siselect);
       for (auto &csr : *aia_sireg->get_csrmap())