virtual_field.emb

# Copyright 2019 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

-- Tests for virtual fields:
--
-- *   `let` constructs
-- *   TODO(bolms@): `transform` annotations
-- *   TODO(bolms@): `read` and `write` annotations

[$default byte_order: "LittleEndian"]
[(cpp) namespace: "emboss::test"]


struct StructureWithConstants:
  let ten = 10
  let twenty = 20
  let four_billion = 4_000_000_000
  let ten_billion = 10_000_000_000
  let minus_ten_billion = -10_000_000_000
  0 [+4]  UInt  value
  let alias_of_value = value
  let alias_of_alias_of_value = alias_of_value
  let alias_of_ten = ten
  let alias_of_alias_of_ten = alias_of_ten


struct StructureWithComputedValues:
  0 [+4]  UInt  value
  let doubled  = value * 2
  let plus_ten = value + 10
  let signed_doubled  = value2 * 2
  let signed_plus_ten = value2 + 10
  let product = value * value2
  4 [+4]  Int  value2


struct StructureWithConditionalValue:
  0 [+4]  UInt  x
  if x < 0x8000_0000:
    let two_x = x * 2
  let x_plus_one = x + 1


struct StructureWithValueInCondition:
  let two_x = x * 2
  0 [+4]    UInt  x
  if two_x < 100:
    4 [+4]  UInt  if_two_x_lt_100


struct StructureWithValuesInLocation:
  let two_x = x * 2
  0     [+4]      UInt     x
  two_x [+4]      UInt     offset_two_x
  4     [+two_x]  UInt:32  size_two_x


struct StructureWithBoolValue:
  let x_is_ten = x == 10
  0 [+4]  UInt  x


struct StructureWithEnumValue:
  enum Category:
    SMALL = 1
    LARGE = 2
  let x_size = x < 100 ? Category.SMALL : Category.LARGE
  0 [+4]  UInt  x


struct StructureWithBitsWithValue:
  0 [+4]  BitsWithValue  b
  let alias_of_b_sum = b.sum
  let alias_of_b_a = b.a


bits BitsWithValue:
  0  [+16]  UInt  a
  16 [+16]  UInt  b
  let sum = a + b


struct StructureUsingForeignConstants:
  StructureWithConstants.ten [+4]  UInt  x
  let one_hundred = StructureWithConstants.twenty * 5


struct SubfieldOfAlias:
  0 [+4]    struct  header:
    0 [+2]  UInt    size
    2 [+2]  UInt    message_id
  let h = header
  let size = h.size


struct RestrictedAlias:
  0 [+4]  BitsWithValue  a_b
  4 [+1]  UInt  alias_switch
  if alias_switch > 10:
    let a_b_alias = a_b


struct HasField:
  0 [+1]  UInt  z
  if $present(x.y):
    let y = x.y
  if z > 10:
    1 [+2]  struct  x:
      0 [+1]  UInt  v
      if v > 10:
        1 [+1]  UInt  y
  if $present(x):
    let x_has_y = $present(x.y)


struct VirtualUnconditionallyUsesConditional:
  0 [+1]  UInt  x
  if x == 0:
    1 [+1]  UInt  xc

  let x_nor_xc = x == 0 && xc == 0


struct UsesSize:
  0 [+1]  bits  r:
    0 [+8]  UInt  q
    let q_plus_bit_size = q + $size_in_bits
  let r_q_plus_byte_size = r.q + $size_in_bytes


struct UsesExternalSize:
  0                [+4]                                      StructureWithConstants  x
  x.$size_in_bytes [+StructureWithConstants.$size_in_bytes]  StructureWithConstants  y


struct ImplicitWriteBack:
  0 [+1]  UInt  x
  let x_plus_ten = x + 10
  let ten_plus_x = 10 + x
  let x_minus_ten = x - 10
  let ten_minus_x = 10 - x
  let ten_minus_x_plus_ten = (10 - x) + 10