[PATCH v3] RISC-V: Elimilate warning in class vcreate

[Li Xu <xuli1@eswincomputing.com>]

From: xuli <xuli1@eswincomputing.com>

The following is the content of class vcreate:
class vcreate : public function_base
{
public:
  gimple *fold (gimple_folder &f) const override
  {
    ....
  }

  rtx expand (function_expander &e) const override
  {
    return NULL_RTX;
  }
};

The warning caused is:
./riscv-gcc/gcc/config/riscv/riscv-vector-builtins-bases.cc:1719:34:
  warning: unused parameter 'e' [-Wunused-parameter]
  rtx expand (function_expander &e) const override
                                 ^

gcc/ChangeLog:

        * config/riscv/riscv-vector-builtins-bases.cc: remove unused parameter e and replace NULL_RTX with gcc_unreachable.
---
 gcc/config/riscv/riscv-vector-builtins-bases.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gcc/config/riscv/riscv-vector-builtins-bases.cc b/gcc/config/riscv/riscv-vector-builtins-bases.cc
index be3df2c1ea2..ee218a03017 100644
--- a/gcc/config/riscv/riscv-vector-builtins-bases.cc
+++ b/gcc/config/riscv/riscv-vector-builtins-bases.cc
@@ -1856,9 +1856,9 @@ public:
     return clobber;
   }
 
-  rtx expand (function_expander &e) const override
+  rtx expand (function_expander &) const override
   {
-    return NULL_RTX;
+    gcc_unreachable ();
   }
 };
 
-- 
2.17.1