Difftest: compare fp regs when difftest as reference

include/isa/riscv64.h

@@ -18,6 +18,10 @@ typedef struct {
     uint64_t _64;
   } gpr[32];
 
+  union {
+    uint64_t _64;
+  } fpr[32];
+
   uint64_t pc;
   uint64_t mstatus, mcause, mepc;
   uint64_t sstatus, scause, sepc;

src/isa/riscv64/difftest/difftest.h

 #ifndef __RISCV64_DIFF_TEST_H__
 #define __RISCV64_DIFF_TEST_H__
 
-#define DIFFTEST_REG_SIZE (sizeof(uint64_t) * (32 + 1 + 6)) // GRPs + pc + [m|s][status|cause|epc]
+#define DIFFTEST_REG_SIZE (sizeof(uint64_t) * (32 + 32 + 1 + 6)) // GRPs + FPRs + pc + [m|s][status|cause|epc]
 
 void isa_difftest_getregs_hook(void);
 void isa_difftest_setregs_hook(void);

tools/qemu-diff/include/isa/riscv64.h

@@ -9,10 +9,11 @@
 union isa_gdb_regs {
   struct {
     uint64_t gpr[32];
+    uint64_t fpr[32];
     uint64_t pc;
   };
   struct {
-    uint32_t array[77];
+    uint32_t array[DIFFTEST_REG_SIZE/sizeof(uint32_t)];
   };
 };