elif_scope

Description

Specifies the current elif_scope code block to be executed if previous if_scope and elif_scope are not true and the current elif_scope is true.

The pseudocode is as follows:

# When cond1 is true, execute the if_scope code block.
if_scope(cond1)

# Execute the elif_scope code block if if_scope is not true while cond2 in this statement is true.
# The first elif_scope statement must be after the if_scope function.
elif_scope(cond2)

# Execute the elif_scope code block when the preceding if_scope and elif_scope statements are not true while cond3 in this statement is true.
elif_scope(cond3)

Prototype

elif_scope(cond)

Parameters

Table 1 Parameter description

Parameter

Input/Output

Description

cond

Input

It supports the InputScalar, Scalar, immediate (int and float), Expr, and bool data types, and any, all, and negate functions.

Specifically,
  • Arguments of the Scalar and InputScalar types are automatically converted into Exprs. For example, if the argument name is a, it is converted into a!=0.
  • Arguments of the Expr type are automatically converted into Exprs with !=0. For example, if the argument is scalar // 2, it is converted to scalar // 2!=0.
NOTICE:

The Expr supports the following operators:

  • Comparison operators: >, <, !=, ==, >=, <=
  • Arithmetic operators: +, , *, /, //, %
  • Bitwise operators: &, |, <<, >>

You can use supported operators to form a complex expression. However, the comparison operators cannot be used together. For example, if you want to express n > 1 and n < 4:

  • The following is not supported:

    1 < n < 4

  • The recommended expression is:

    tik.all((1 < n) , (n < 4))

Applicability

Atlas 200/300/500 Inference Product

Atlas Training Series Product

Restrictions

  • Use this conditional statement after the if_scope or elif_scope function.
  • The number of elif_scope and else_scope statements following if_scope must not exceed 400.
  • The Scalar in Expr does not support the following data types:

    For the Atlas 200/300/500 Inference Product, the Expr must not contain Scalars of type float16 or float32.

    For the Atlas Training Series Product, the Expr must not contain Scalars of type float16.

Returns

A TikWithScope object.

It is inherited from WithScope of TVM.

Example

tik_instance = tik.Tik()

cond = tik_instance.InputScalar(dtype="int16", name="cond")
src_gm = tik_instance.Tensor(dtype="int64", shape=(16, ),
                             scope=tik.scope_gm, name="src_gm")
dst_ub = tik_instance.Tensor(dtype="int64", shape=(4, ),
                             scope=tik.scope_ubuf, name="dst_ub")
dst_gm = tik_instance.Tensor(dtype="int64", shape=(4, ),
                             scope=tik.scope_gm, name="dst_gm")
# Initialize dst to src_gm[0:3].
tik_instance.data_move(dst_ub, src_gm[0:3,], 0, 1, 1, 0, 0)

# Move slices of src to dst based on cond's value.
# When cond==1 is true, execute the if_scope code block.
with tik_instance.if_scope(cond == 1):
    tik_instance.data_move(dst_ub, src_gm[4:7,], 0, 1, 1, 0, 0)
# When cond==1 is false and cond==2 is true, execute the elif_scope code block.
with tik_instance.elif_scope(cond == 2):
    tik_instance.data_move(dst_ub, src_gm[8:11,], 0, 1, 1, 0, 0)
# When cond==1 and cond==2 are false while cond==3 is true, execute the elif_scope code block.
with tik_instance.elif_scope(cond == 3):
    tik_instance.data_move(dst_ub, src_gm[12:15,], 0, 1, 1, 0, 0)

# Move dst to the Global Memory for output.
tik_instance.data_move(dst_gm, dst_ub, 0, 1, 1, 0, 0)

tik_instance.BuildCCE(kernel_name="if_scope", inputs=[src_gm, cond], outputs=[dst_gm])

Result example

Input (src_gm):
[0, 1, 2,..., 15]

Input (cond):
3

Output (dst_gm):
[12, 13, 14, 15]