HLSL shader语法有问题，无法编译通过

Question

struct VSIn
{
float3 Pos : POSITION;
float3 Inf : INFORM;
};

struct GSIn
{
float3 Pos : POSITION;
float3 Inf : INFORM;
};

struct PSIn
{
float4 Pos : SV_POSITION;
float3 Tex : TEXCOORD0;
float3 Inf : INFORM;
};

cbuffer cbm : register(b0)
{
matrix g_mWorldViewProj;
matrix g_mInvView;
};

Texture3D g_txParitcle : register(t0);

float3 g_positions[4] =
{
float3(-1, 1, 0),
float3(1, 1, 0),
float3(-1, -1, 0),
float3(1, -1, 0),
};
float2 g_texcoords[4] =
{
float2(0, 0),
float2(1, 0),
float2(0, 1),
float2(1, 1),
};

GSIn VSmain(VSIn input)
{
GSIn output;

output.Pos = input.Pos;
output.Inf = input.Inf;
return output;
}

[maxvertexcount(4)]
void GSmain(point GSIn input[1], inout TriangleStream SpriteStream)
{
PSIn output;

//if (input[0].Life > -1)
if (input[0].Inf.x > -1)
{
[unroll] for (int i = 0; i<4; i++)
{
float3 position = g_positions[i] * input[0].Inf.y;
position = mul(position, (float3x3)g_mInvView) + input[0].Pos;
output.Pos = mul(float4(position, 1.0), g_mWorldViewProj);

output.Tex = float3(g_texcoords[i], input[0].Inf.x);

output.Inf = input[0].Inf;

SpriteStream.Append(output);
}
SpriteStream.RestartStrip();
}
}

float4 PSmain(PSIn input) : SV_TARGET
{
float4 particleSample = g_txParitcle.Sample(g_samPoint, input.Tex);
//particleSample.a *= input.Alpha;
particleSample.a *= input.Inf.z;

return particleSample;
}

弹出的错误框写的是对于geometry shader有：
warning X3554:unknown attribute maxvertexcount, or attribute invalid for this statement, valid attribute are: clipplanes
error X3514: 'GSmain':input parameter 'input' can not have a geometry specifier
对于ps shader，信息是：
error X4502:invalid vs_4_0 output semantic 'SV_TARGET'