vcmp

Description

Compares lhs with rhs element-wise based on operation. The operations specified by operation are selected from eq, ne, lt, gt, le, and ge, which indicate ==, !=, <, >, <=, and >=, respectively. If the expression is true, True is returned when the mode is bool, and 1 is returned when the mode is bit. If the expression is false, False is returned when the mode is bool, and 0 is returned when the mode is bit.

The following describes the operations by using expressions. x indicates an element in lhs, y indicates an element in rhs, z indicates an element of the result tensor, and n (a value ranging from 0 to 7) indicates the index of the bit dimension of the result tensor. The expressions are as follows:

• mode=='bool':
  • lt: z = True (x < y) or False (x >= y)
  • gt: z = True (x > y) or False (x <= y)
  • le: z = True (x <= y) or False (x > y)
  • ge: z = True (x >= y) or False (x < y)
  • eq: z = True (x == y) or False (x != y)
  • ne: z = True (x != y) or False (x == y)

• mode=='bit':
  • lt: z[n] = 1 (x < y) or 0 (x >= y)
  • gt: z[n] = 1 (x > y) or 0 (x <= y)
  • le: z[n] = 1 (x <= y) or 0 (x > y)
  • ge: z[n] = 1 (x >= y) or 0 (x < y)
  • eq: z[n] = 1 (x == y) or 0 (x != y)
  • ne: z[n] = 1 (x != y) or 0 (x == y)

Prototype

vcmp(lhs, rhs, operation='lt', mode='bool')

Parameters

• lhs: a tvm.tensor for the left operand.
• rhs: a tvm.tensor or scalar for the right operand.
• operation: operation type selected from eq, ne, lt, gt, ge, or le. Defaults to lt.
• mode: mode selected from bool or bit. Defaults to bool.

The left and right operands for comparison must have the same data type.

• Atlas 200/300/500 Inference Product: supports float16.
• Atlas Training Series Product: supports float16, float32, and int64.

Returns

res_tensor: a tvm.tensor for the result tensor If mode is set to bool, the data type is bool. If mode is set to bit, the data type is uint8.

Restrictions

• When mode is set to bool and the tbe.dsl.build API is called for build, bool_storage_as_1bit in the passed configuration parameter must be set to False. Otherwise, unexpected output shape will be obtained.

  bool_storage_as_1bit is set to True by default, indicating that it is stored as 1-bit data.

  The following gives a build configuration file template.

  with tvm.target.cce():
      schedule = tbe.dsl.auto_schedule(res)
  config = {"name": kernel_name,
            "tensor_list": [data_x, data_y, res],
            "bool_storage_as_1bit": False}
  tbe.dsl.build(schedule, config)

• When mode is set to bit, the last dimension of the shape of the left operand must be divisible by 8.
• If the right operand is also a tensor, the two tensors must have the same shape.

Applicability

Atlas 200/300/500 Inference Product

Atlas Training Series Product

Example

from tbe import tvm
from tbe import dsl
shape = (1024,1024)
input_dtype = "float16"
data1 = tvm.placeholder(shape, name="data1", dtype=input_dtype)
data2 = tvm.placeholder(shape, name="data2", dtype=input_dtype)
res = dsl.vcmp(data1, data2, 'lt', 'bit')