diff --git a/target-alpha/helper.h b/target-alpha/helper.h
index a545c5c..4eb3b6f 100644
--- a/target-alpha/helper.h
+++ b/target-alpha/helper.h
@@ -19,9 +19,6 @@ DEF_HELPER_1(cttz, i64, i64)
 
 DEF_HELPER_2(zap, i64, i64, i64)
 DEF_HELPER_2(zapnot, i64, i64, i64)
-DEF_HELPER_2(inswh, i64, i64, i64)
-DEF_HELPER_2(inslh, i64, i64, i64)
-DEF_HELPER_2(insqh, i64, i64, i64)
 
 DEF_HELPER_2(cmpbge, i64, i64, i64)
 
diff --git a/target-alpha/op_helper.c b/target-alpha/op_helper.c
index b6ec0e8..d7f4fb2 100644
--- a/target-alpha/op_helper.c
+++ b/target-alpha/op_helper.c
@@ -185,24 +185,6 @@ uint64_t helper_zapnot(uint64_t val, uint64_t mask)
     return byte_zap(val, ~mask);
 }
 
-uint64_t helper_inswh(uint64_t val, uint64_t mask)
-{
-    val >>= 64 - ((mask & 7) * 8);
-    return byte_zap(val, ~((0x03 << (mask & 7)) >> 8));
-}
-
-uint64_t helper_inslh(uint64_t val, uint64_t mask)
-{
-    val >>= 64 - ((mask & 7) * 8);
-    return byte_zap(val, ~((0x0F << (mask & 7)) >> 8));
-}
-
-uint64_t helper_insqh(uint64_t val, uint64_t mask)
-{
-    val >>= 64 - ((mask & 7) * 8);
-    return byte_zap(val, ~((0xFF << (mask & 7)) >> 8));
-}
-
 uint64_t helper_cmpbge (uint64_t op1, uint64_t op2)
 {
     uint8_t opa, opb, res;
diff --git a/target-alpha/translate.c b/target-alpha/translate.c
index 92d001d..d361ffe 100644
--- a/target-alpha/translate.c
+++ b/target-alpha/translate.c
@@ -625,6 +625,48 @@ static void gen_ext_l(int ra, int rb, int rc, int islit,
     }
 }
 
+/* INSWH, INSLH, INSQH */
+static void gen_ins_h(int ra, int rb, int rc, int islit,
+                      uint8_t lit, uint8_t byte_mask)
+{
+    if (unlikely(rc == 31))
+        return;
+    else if (unlikely(ra == 31) || (islit && (lit & 7) == 0))
+        tcg_gen_movi_i64(cpu_ir[rc], 0);
+    else {
+        TCGv tmp = tcg_temp_new();
+
+        /* The instruction description has us left-shift the byte mask
+           and extract bits <15:8> and apply that zap at the end.  This
+           is equivalent to simply performing the zap first and shifting
+           afterward.  */
+        gen_zapnoti (tmp, cpu_ir[ra], byte_mask);
+
+        if (islit) {
+            /* Note that we have handled the lit==0 case above.  */
+            tcg_gen_shri_i64 (cpu_ir[rc], tmp, 64 - (lit & 7) * 8);
+        } else {
+            TCGv shift = tcg_temp_new();
+
+            /* If (B & 7) == 0, we need to shift by 64 and leave a zero.
+               Do this portably by splitting the shift into two parts:
+               shift_count-1 and 1.  Arrange for the -1 by using
+               ones-complement instead of twos-complement in the negation:
+               ~((B & 7) * 8) & 63.  */
+
+            tcg_gen_andi_i64(shift, cpu_ir[rb], 7);
+            tcg_gen_shli_i64(shift, shift, 3);
+            tcg_gen_not_i64(shift, shift);
+            tcg_gen_andi_i64(shift, shift, 0x3f);
+
+            tcg_gen_shr_i64(cpu_ir[rc], tmp, shift);
+            tcg_gen_shri_i64(cpu_ir[rc], cpu_ir[rc], 1);
+            tcg_temp_free(shift);
+        }
+        tcg_temp_free(tmp);
+    }
+}
+
 /* INSBL, INSWL, INSLL, INSQL */
 static void gen_ins_l(int ra, int rb, int rc, int islit,
                       uint8_t lit, uint8_t byte_mask)
@@ -750,9 +792,6 @@ ARITH3(addlv)
 ARITH3(sublv)
 ARITH3(addqv)
 ARITH3(subqv)
-ARITH3(inswh)
-ARITH3(inslh)
-ARITH3(insqh)
 ARITH3(umulh)
 ARITH3(mullv)
 ARITH3(mulqv)
@@ -1479,7 +1518,7 @@ static inline int translate_one(DisasContext *ctx, uint32_t insn)
             break;
         case 0x57:
             /* INSWH */
-            gen_inswh(ra, rb, rc, islit, lit);
+            gen_ins_h(ra, rb, rc, islit, lit, 0x03);
             break;
         case 0x5A:
             /* EXTWH */
@@ -1491,7 +1530,7 @@ static inline int translate_one(DisasContext *ctx, uint32_t insn)
             break;
         case 0x67:
             /* INSLH */
-            gen_inslh(ra, rb, rc, islit, lit);
+            gen_ins_h(ra, rb, rc, islit, lit, 0x0f);
             break;
         case 0x6A:
             /* EXTLH */
@@ -1503,7 +1542,7 @@ static inline int translate_one(DisasContext *ctx, uint32_t insn)
             break;
         case 0x77:
             /* INSQH */
-            gen_insqh(ra, rb, rc, islit, lit);
+            gen_ins_h(ra, rb, rc, islit, lit, 0xff);
             break;
         case 0x7A:
             /* EXTQH */
