diff --git a/OpenCL/inc_rp.cl b/OpenCL/inc_rp.cl
index 3ad05b350..12ae46933 100644
--- a/OpenCL/inc_rp.cl
+++ b/OpenCL/inc_rp.cl
@@ -1799,17 +1799,16 @@ inline u32 rule_op_mangle_dupechar_last (const u32 p0, const u32 p1, u32 buf0[4]
 
   u32 tmp = 0;
 
-  switch (in_len1 / 4)
-  {
-    case  0:  tmp = (buf0[0] >> sh) & 0xff; break;
-    case  1:  tmp = (buf0[1] >> sh) & 0xff; break;
-    case  2:  tmp = (buf0[2] >> sh) & 0xff; break;
-    case  3:  tmp = (buf0[3] >> sh) & 0xff; break;
-    case  4:  tmp = (buf1[0] >> sh) & 0xff; break;
-    case  5:  tmp = (buf1[1] >> sh) & 0xff; break;
-    case  6:  tmp = (buf1[2] >> sh) & 0xff; break;
-    case  7:  tmp = (buf1[3] >> sh) & 0xff; break;
-  }
+  tmp |=                     (in_len1 <  4)  ? buf0[0] : 0;
+  tmp |= ((in_len1 >=  4) && (in_len1 <  8)) ? buf0[1] : 0;
+  tmp |= ((in_len1 >=  8) && (in_len1 < 12)) ? buf0[2] : 0;
+  tmp |= ((in_len1 >= 12) && (in_len1 < 16)) ? buf0[3] : 0;
+  tmp |= ((in_len1 >= 16) && (in_len1 < 20)) ? buf1[0] : 0;
+  tmp |= ((in_len1 >= 20) && (in_len1 < 24)) ? buf1[1] : 0;
+  tmp |= ((in_len1 >= 24) && (in_len1 < 28)) ? buf1[2] : 0;
+  tmp |=  (in_len1 >= 28)                    ? buf1[3] : 0;
+
+  tmp = (tmp >> sh) & 0xff;
 
   u32 out_len = in_len;
 
diff --git a/src/rp_kernel_on_cpu.c b/src/rp_kernel_on_cpu.c
index 9311c5e54..b26565fed 100644
--- a/src/rp_kernel_on_cpu.c
+++ b/src/rp_kernel_on_cpu.c
@@ -1881,17 +1881,16 @@ static u32 rule_op_mangle_dupechar_last (MAYBE_UNUSED const u32 p0, MAYBE_UNUSED
 
   u32 tmp = 0;
 
-  switch (in_len1 / 4)
-  {
-    case  0:  tmp = (buf0[0] >> sh) & 0xff; break;
-    case  1:  tmp = (buf0[1] >> sh) & 0xff; break;
-    case  2:  tmp = (buf0[2] >> sh) & 0xff; break;
-    case  3:  tmp = (buf0[3] >> sh) & 0xff; break;
-    case  4:  tmp = (buf1[0] >> sh) & 0xff; break;
-    case  5:  tmp = (buf1[1] >> sh) & 0xff; break;
-    case  6:  tmp = (buf1[2] >> sh) & 0xff; break;
-    case  7:  tmp = (buf1[3] >> sh) & 0xff; break;
-  }
+  tmp |=                     (in_len1 <  4)  ? buf0[0] : 0;
+  tmp |= ((in_len1 >=  4) && (in_len1 <  8)) ? buf0[1] : 0;
+  tmp |= ((in_len1 >=  8) && (in_len1 < 12)) ? buf0[2] : 0;
+  tmp |= ((in_len1 >= 12) && (in_len1 < 16)) ? buf0[3] : 0;
+  tmp |= ((in_len1 >= 16) && (in_len1 < 20)) ? buf1[0] : 0;
+  tmp |= ((in_len1 >= 20) && (in_len1 < 24)) ? buf1[1] : 0;
+  tmp |= ((in_len1 >= 24) && (in_len1 < 28)) ? buf1[2] : 0;
+  tmp |=  (in_len1 >= 28)                    ? buf1[3] : 0;
+
+  tmp = (tmp >> sh) & 0xff;
 
   u32 out_len = in_len;