target/riscv: rvb: count bits set

Signed-off-by: Kito Cheng <kito.cheng@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Message-id: 20210505160620.15723-4-frank.chang@sifive.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/insn32.decode

@@ -662,7 +662,9 @@ vamomaxud_v     11100 . . ..... ..... 111 ..... 0101111 @r_wdvm
 # *** RV32B Standard Extension ***
 clz        011000 000000 ..... 001 ..... 0010011 @r2
 ctz        011000 000001 ..... 001 ..... 0010011 @r2
+cpop       011000 000010 ..... 001 ..... 0010011 @r2
 
 # *** RV64B Standard Extension (in addition to RV32B) ***
 clzw       0110000 00000 ..... 001 ..... 0011011 @r2
 ctzw       0110000 00001 ..... 001 ..... 0011011 @r2
+cpopw      0110000 00010 ..... 001 ..... 0011011 @r2

target/riscv/insn_trans/trans_rvb.c.inc

@@ -29,6 +29,12 @@ static bool trans_ctz(DisasContext *ctx, arg_ctz *a)
     return gen_unary(ctx, a, gen_ctz);
 }
 
+static bool trans_cpop(DisasContext *ctx, arg_cpop *a)
+{
+    REQUIRE_EXT(ctx, RVB);
+    return gen_unary(ctx, a, tcg_gen_ctpop_tl);
+}
+
 static bool trans_clzw(DisasContext *ctx, arg_clzw *a)
 {
     REQUIRE_64BIT(ctx);
@@ -42,3 +48,10 @@ static bool trans_ctzw(DisasContext *ctx, arg_ctzw *a)
     REQUIRE_EXT(ctx, RVB);
     return gen_unary(ctx, a, gen_ctzw);
 }
+
+static bool trans_cpopw(DisasContext *ctx, arg_cpopw *a)
+{
+    REQUIRE_64BIT(ctx);
+    REQUIRE_EXT(ctx, RVB);
+    return gen_unary(ctx, a, gen_cpopw);
+}

target/riscv/translate.c

@@ -561,6 +561,12 @@ static void gen_clzw(TCGv ret, TCGv arg1)
     tcg_gen_subi_tl(ret, ret, 32);
 }
 
+static void gen_cpopw(TCGv ret, TCGv arg1)
+{
+    tcg_gen_ext32u_tl(arg1, arg1);
+    tcg_gen_ctpop_tl(ret, arg1);
+}
+
 static bool gen_arith(DisasContext *ctx, arg_r *a,
                       void(*func)(TCGv, TCGv, TCGv))
 {