blob: e817571aab3ad5e11b55d7b4f6468cc044074d96 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
// SPDX-License-Identifier: Apache-2.0
package firrtl
package transforms
import firrtl.annotations._
import firrtl.passes.PassException
/** Indicate that DCE should not be run */
case object NoDCEAnnotation extends NoTargetAnnotation
/** Indicate that ConstantPropagation should not be run */
case object NoConstantPropagationAnnotation extends NoTargetAnnotation
/** Lets an annotation mark its ReferenceTarget members as DontTouch
*
* This permits a transform to run and remove its associated annotations,
* thus making their ReferenceTargets new candidates for optimization. This
* removes the need for the pass writer to reason about pre-existing
* DontTouchAnnotations that may touch the same node.
*/
trait HasDontTouches { self: Annotation =>
def dontTouches: Iterable[ReferenceTarget]
}
/**
* A globalized form of HasDontTouches which applies to all ReferenceTargets
* provided with the annotation
*/
trait DontTouchAllTargets extends HasDontTouches { self: Annotation =>
def dontTouches: Iterable[ReferenceTarget] = getTargets.collect {
case rT: ReferenceTarget => rT
}
}
/** A component that should be preserved
*
* DCE treats the component as a top-level sink of the circuit
*/
case class DontTouchAnnotation(target: ReferenceTarget)
extends SingleTargetAnnotation[ReferenceTarget]
with DontTouchAllTargets {
def targets = Seq(target)
def duplicate(n: ReferenceTarget) = this.copy(n)
}
object DontTouchAnnotation {
class DontTouchNotFoundException(module: String, component: String)
extends PassException(
s"""|Target marked dontTouch ($module.$component) not found!
|It was probably accidentally deleted. Please check that your custom transforms are not responsible and then
|file an issue on GitHub: https://github.com/freechipsproject/firrtl/issues/new""".stripMargin
)
def errorNotFound(module: String, component: String) =
throw new DontTouchNotFoundException(module, component)
}
/** An [[firrtl.ir.ExtModule]] that can be optimized
*
* Firrtl does not know the semantics of an external module. This annotation provides some
* "greybox" information that the external module does not have any side effects. In particular,
* this means that the external module can be Dead Code Eliminated.
*
* @note Unlike [[DontTouchAnnotation]], we don't care if the annotation is deleted
*/
case class OptimizableExtModuleAnnotation(target: ModuleName) extends SingleTargetAnnotation[ModuleName] {
def duplicate(n: ModuleName) = this.copy(n)
}
|
