target/mips: Remove unused register from MSA 2R/2RF instruction format

Commits cbe50b9 ("target-mips: add MSA VEC/2R format instructions")
and 3bdeb68 ("target-mips: add MSA 2RF format instructions") added
the MSA 2R/2RF instructions. However these instructions don't use any
target vector register, so remove the unused TCG temporaries.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211003175743.3738710-2-f4bug@amsat.org>

target/mips/tcg/msa_translate.c

@@ -1942,13 +1942,11 @@ static void gen_msa_2r(DisasContext *ctx)
 {
 #define MASK_MSA_2R(op)     (MASK_MSA_MINOR(op) | (op & (0x1f << 21)) | \
                             (op & (0x7 << 18)))
-    uint8_t wt = (ctx->opcode >> 16) & 0x1f;
     uint8_t ws = (ctx->opcode >> 11) & 0x1f;
     uint8_t wd = (ctx->opcode >> 6) & 0x1f;
     uint8_t df = (ctx->opcode >> 16) & 0x3;
     TCGv_i32 twd = tcg_const_i32(wd);
     TCGv_i32 tws = tcg_const_i32(ws);
-    TCGv_i32 twt = tcg_const_i32(wt);
     TCGv_i32 tdf = tcg_const_i32(df);
 
     switch (MASK_MSA_2R(ctx->opcode)) {
@@ -2018,21 +2016,18 @@ static void gen_msa_2r(DisasContext *ctx)
 
     tcg_temp_free_i32(twd);
     tcg_temp_free_i32(tws);
-    tcg_temp_free_i32(twt);
     tcg_temp_free_i32(tdf);
 }
 
 static void gen_msa_2rf(DisasContext *ctx)
 {
 #define MASK_MSA_2RF(op)    (MASK_MSA_MINOR(op) | (op & (0x1f << 21)) | \
                             (op & (0xf << 17)))
-    uint8_t wt = (ctx->opcode >> 16) & 0x1f;
     uint8_t ws = (ctx->opcode >> 11) & 0x1f;
     uint8_t wd = (ctx->opcode >> 6) & 0x1f;
     uint8_t df = (ctx->opcode >> 16) & 0x1;
     TCGv_i32 twd = tcg_const_i32(wd);
     TCGv_i32 tws = tcg_const_i32(ws);
-    TCGv_i32 twt = tcg_const_i32(wt);
     /* adjust df value for floating-point instruction */
     TCGv_i32 tdf = tcg_const_i32(df + 2);
 
@@ -2089,7 +2084,6 @@ static void gen_msa_2rf(DisasContext *ctx)
 
     tcg_temp_free_i32(twd);
     tcg_temp_free_i32(tws);
-    tcg_temp_free_i32(twt);
     tcg_temp_free_i32(tdf);
 }