clip area shader

First of all, I don't have any idea about shader programming but I need it for my game so I found a clip area shader on the internet then I was trying to modify it and add some features to it ! I added shader to my sprite and checked it on my PC and some android devices but after that I've checked it on HTC One (My friend mobile) but weird problem was happening !

As you see the left side is not clipping visually.

The first shader I found just had width and length for clipping sprite then I added width from left and width from right and color tint to the shader.

There is a code :

 Shader "Sprites/ClipAreaWithAlpha"
 {
     Properties
     {
         _Color ("Color Tint", Color) = (1,1,1,1)
         _MainTex ("Base (RGB), Alpha (A)", 2D) = "white" {}
         _Length ("Length", Range(0.0, 1.0)) = 1.0
         _WidthR("Width from right", Range(0.0, 1.0)) = 1.0
         _WidthL ("Width from left", Range(0.0, 1.0)) = 0.0
      }
 
     SubShader
     {
         LOD 200
 
         Tags
         {
             "Queue" = "Transparent"
             "IgnoreProjector" = "True"
             "RenderType" = "Transparent"
         }
 
         Pass
         {
             Cull Off
             Lighting Off
             ZWrite Off
             Offset -1, -1
             Fog { Mode Off }
             ColorMask RGB
             Blend SrcAlpha OneMinusSrcAlpha
 
             CGPROGRAM
             #pragma vertex vert
             #pragma fragment frag
 
             #include "UnityCG.cginc"
 
             sampler2D _MainTex;
             float4 _MainTex_ST;
             float _Length;
             float _WidthR;
             float _WidthL;
             half4 _Color;
 
             struct appdata_t
             {
                 float4 vertex : POSITION;
                 float2 texcoord : TEXCOORD0;
             };
 
             struct v2f
             {
                 float4 vertex : POSITION;
                 float2 texcoord : TEXCOORD0;
                 half4 color : COLOR;
             };
 
             v2f vert (appdata_t v)
             {
                 v2f o;
                 o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
                 o.texcoord = v.texcoord;
                 o.color = _Color;
                 return o;
             }
 
             half4 frag (v2f IN) : COLOR
             {
                 if ((IN.texcoord.x<_WidthL) || (IN.texcoord.x>_WidthR) || (IN.texcoord.y<0) || (IN.texcoord.y>_Length))
                 {
                     half4 colorTransparent = half4(0,0,0,0) ;
                     return colorTransparent;
                 }
                 else
                 {
                     half4 tex = tex2D(_MainTex, IN.texcoord);
                     tex.a = IN.color.a;
                     return tex;
                 }
             }
             ENDCG
         }
     }
 }

As I said before this shader is ok on another android devices that I checked but on HTC One it doesn't work nicely and correctly. I don't know where the problem is! I'm thankful for solution.

And this shader has this warning : MaterialPropertyBlock is used to modify these values