diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
index 287920ee9b..f09f8d5faf 100644
--- a/target/riscv/insn32.decode
+++ b/target/riscv/insn32.decode
@@ -720,6 +720,7 @@ gorcw      0010100 .......... 101 ..... 0111011 @r
 sh1add_uw  0010000 .......... 010 ..... 0111011 @r
 sh2add_uw  0010000 .......... 100 ..... 0111011 @r
 sh3add_uw  0010000 .......... 110 ..... 0111011 @r
+add_uw     0000100 .......... 000 ..... 0111011 @r
 
 bsetiw     0010100 .......... 001 ..... 0011011 @sh5
 bclriw     0100100 .......... 001 ..... 0011011 @sh5
@@ -729,3 +730,5 @@ sroiw      0010000 .......... 101 ..... 0011011 @sh5
 roriw      0110000 .......... 101 ..... 0011011 @sh5
 greviw     0110100 .......... 101 ..... 0011011 @sh5
 gorciw     0010100 .......... 101 ..... 0011011 @sh5
+
+slli_uw    00001. ........... 001 ..... 0011011 @sh
diff --git a/target/riscv/insn_trans/trans_rvb.c.inc b/target/riscv/insn_trans/trans_rvb.c.inc
index b27114a068..9e81f6e3de 100644
--- a/target/riscv/insn_trans/trans_rvb.c.inc
+++ b/target/riscv/insn_trans/trans_rvb.c.inc
@@ -410,3 +410,29 @@ static bool trans_sh##SHAMT##add_uw(DisasContext *ctx,        \
 GEN_TRANS_SHADD_UW(1)
 GEN_TRANS_SHADD_UW(2)
 GEN_TRANS_SHADD_UW(3)
+
+static bool trans_add_uw(DisasContext *ctx, arg_add_uw *a)
+{
+    REQUIRE_64BIT(ctx);
+    REQUIRE_EXT(ctx, RVB);
+    return gen_arith(ctx, a, gen_add_uw);
+}
+
+static bool trans_slli_uw(DisasContext *ctx, arg_slli_uw *a)
+{
+    REQUIRE_64BIT(ctx);
+    REQUIRE_EXT(ctx, RVB);
+
+    TCGv source1 = tcg_temp_new();
+    gen_get_gpr(source1, a->rs1);
+
+    if (a->shamt < 32) {
+        tcg_gen_deposit_z_tl(source1, source1, a->shamt, 32);
+    } else {
+        tcg_gen_shli_tl(source1, source1, a->shamt);
+    }
+
+    gen_set_gpr(a->rd, source1);
+    tcg_temp_free(source1);
+    return true;
+}
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index ae9b5f7a2e..c6e8739614 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -765,6 +765,12 @@ GEN_SHADD_UW(1)
 GEN_SHADD_UW(2)
 GEN_SHADD_UW(3)
 
+static void gen_add_uw(TCGv ret, TCGv arg1, TCGv arg2)
+{
+    tcg_gen_ext32u_tl(arg1, arg1);
+    tcg_gen_add_tl(ret, arg1, arg2);
+}
+
 static bool gen_arith(DisasContext *ctx, arg_r *a,
                       void(*func)(TCGv, TCGv, TCGv))
 {