[LLM]Fix Arc falcon abnormal output issue (intel#9096)

* update

* update

* fix error & style

* fix style

* update train

* to input_seq_size

Author: cyita

python/llm/src/bigdl/llm/transformers/low_bit_linear.py

@@ -288,10 +288,10 @@ def ggml_matmul_src1_x_src0_t(src0: torch.Tensor,
 class MatMulLowBit(torch.autograd.Function):
 
     @staticmethod
-    def forward(ctx, A, weight):
+    def forward(ctx, A, weight, input_seq_size):
         ctx.is_empty = False
         import linear_q4_0
-        result = linear_q4_0.forward_new(A, weight.data, weight.qtype)
+        result = linear_q4_0.forward_new(A, weight.data, weight.qtype, input_seq_size)
         if any(ctx.needs_input_grad[:2]):
             ctx.tensors = (A, weight)
         else:
@@ -304,14 +304,14 @@ def backward(ctx, grad_output):
         if ctx.is_empty:
             bias_grad = None if ctx.bias is None else torch.zeros_like(ctx.bias)
             return torch.zeros_like(ctx.A), torch.zeros_like(ctx.B), None, bias_grad, None
-        req_gradA, _ = ctx.needs_input_grad
+        req_gradA, _, _ = ctx.needs_input_grad
         A, weight = ctx.tensors
         grad_A, grad_weight = None, None
         if req_gradA:
             dequant_weight = linear_q4_0.dequant(A, weight.data, weight.qtype)
             grad_A = torch.matmul(grad_output, dequant_weight.reshape(weight._shape))
 
-        return grad_A, grad_weight
+        return grad_A, grad_weight, None
 
 
 class LowBitLinear(nn.Linear):
@@ -353,10 +353,12 @@ def forward(self, x: torch.Tensor):
             # disable the conversion when training
             if self.conver_to_half and x_2d.shape[0] > 1 and x_2d.dtype == torch.float32:
                 x_2d = x_2d.half()
+            input_seq_size = x_shape[1]
             if self.training and x_2d.requires_grad:
-                result = MatMulLowBit.apply(x_2d, self.weight)
+                result = MatMulLowBit.apply(x_2d, self.weight, input_seq_size)
             else:
-                result = linear_q4_0.forward_new(x_2d, self.weight.data, self.weight.qtype)
+                result = linear_q4_0.forward_new(x_2d, self.weight.data, self.weight.qtype,
+                                                 input_seq_size)
             new_shape = x_shape[:-1] + (self.out_len,)
             result = result.view(new_shape)
             if self.bias is not None: