Move processor.isa to state.misa, since it really belongs there.

riscv/processor.cc

@@ -64,10 +64,10 @@ void processor_t::parse_isa_string(const char* str)
   const char* all_subsets = "imafdqc";
 
   max_xlen = 64;
-  isa = reg_t(2) << 62;
+  state.misa = reg_t(2) << 62;
 
   if (strncmp(p, "rv32", 4) == 0)
-    max_xlen = 32, isa = reg_t(1) << 30, p += 4;
+    max_xlen = 32, state.misa = reg_t(1) << 30, p += 4;
   else if (strncmp(p, "rv64", 4) == 0)
     p += 4;
   else if (strncmp(p, "rv", 2) == 0)
@@ -83,11 +83,11 @@ void processor_t::parse_isa_string(const char* str)
   }
 
   isa_string = "rv" + std::to_string(max_xlen) + p;
-  isa |= 1L << ('s' - 'a'); // advertise support for supervisor mode
-  isa |= 1L << ('u' - 'a'); // advertise support for user mode
+  state.misa |= 1L << ('s' - 'a'); // advertise support for supervisor mode
+  state.misa |= 1L << ('u' - 'a'); // advertise support for user mode
 
   while (*p) {
-    isa |= 1L << (*p - 'a');
+    state.misa |= 1L << (*p - 'a');
 
     if (auto next = strchr(all_subsets, *p)) {
       all_subsets = next + 1;
@@ -112,7 +112,7 @@ void processor_t::parse_isa_string(const char* str)
   if (supports_extension('Q') && max_xlen < 64)
     bad_isa_string(str);
 
-  max_isa = isa;
+  max_isa = state.misa;
 }
 
 void state_t::reset()
@@ -458,7 +458,7 @@ void processor_t::set_csr(int which, reg_t val)
       mask |= 1L << ('C' - 'A');
       mask &= max_isa;
 
-      isa = (val & mask) | (isa & ~mask);
+      state.misa = (val & mask) | (state.misa & ~mask);
       break;
     }
     case CSR_TSELECT:
@@ -607,7 +607,7 @@ reg_t processor_t::get_csr(int which)
     case CSR_MSCRATCH: return state.mscratch;
     case CSR_MCAUSE: return state.mcause;
     case CSR_MTVAL: return state.mtval;
-    case CSR_MISA: return isa;
+    case CSR_MISA: return state.misa;
     case CSR_MARCHID: return 0;
     case CSR_MIMPID: return 0;
     case CSR_MVENDORID: return 0;

riscv/processor.h

@@ -96,6 +96,7 @@ struct state_t
 
   // control and status registers
   reg_t prv;    // TODO: Can this be an enum instead?
+  reg_t misa;
   reg_t mstatus;
   reg_t mepc;
   reg_t mtval;
@@ -185,7 +186,7 @@ public:
   extension_t* get_extension() { return ext; }
   bool supports_extension(unsigned char ext) {
     if (ext >= 'a' && ext <= 'z') ext += 'A' - 'a';
-    return ext >= 'A' && ext <= 'Z' && ((isa >> (ext - 'A')) & 1);
+    return ext >= 'A' && ext <= 'Z' && ((state.misa >> (ext - 'A')) & 1);
   }
   void check_pc_alignment(reg_t pc) {
     if (unlikely(pc & 2) && !supports_extension('C'))
@@ -302,7 +303,6 @@ private:
   uint32_t id;
   unsigned max_xlen;
   unsigned xlen;
-  reg_t isa;
   reg_t max_isa;
   std::string isa_string;
   bool histogram_enabled;