diff options
| author | Jim Lawson | 2016-07-06 10:01:23 -0700 |
|---|---|---|
| committer | Jim Lawson | 2016-07-18 15:17:56 -0700 |
| commit | c5f9ea3133ef363ff8944e17d94fea79767b6bed (patch) | |
| tree | cc80a6df1eb58f0feaf9f138eb7fe261ccda4ea2 /chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala | |
| parent | 53813f61b7dfe246d214ab966739d01c65c8ecb0 (diff) | |
Rename "Chisel" to "chisel3" (only git mv).
Diffstat (limited to 'chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala')
| -rw-r--r-- | chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala b/chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala new file mode 100644 index 00000000..42d85bfb --- /dev/null +++ b/chiselFrontend/src/main/scala/chisel3/core/BiConnect.scala @@ -0,0 +1,190 @@ +package Chisel + +import internal.Builder.pushCommand +import internal.firrtl.Connect +import scala.language.experimental.macros +import internal.sourceinfo.{SourceInfo, DeprecatedSourceInfo, UnlocatableSourceInfo, WireTransform, SourceInfoTransform} + +/** +* BiConnect.connect executes a bidirectional connection element-wise. +* +* Note that the arguments are left and right (not source and sink) so the +* intent is for the operation to be commutative. +* +* The connect operation will recurse down the left Data (with the right Data). +* An exception will be thrown if a movement through the left cannot be matched +* in the right (or if the right side has extra fields). +* +* See elemConnect for details on how the root connections are issued. +* +*/ + +object BiConnect { + // These are all the possible exceptions that can be thrown. + case class BiConnectException(message: String) extends Exception(message) + // These are from element-level connection + def BothDriversException = + BiConnectException(": Both Left and Right are drivers") + def NeitherDriverException = + BiConnectException(": Neither Left nor Right is a driver") + def UnknownDriverException = + BiConnectException(": Locally unclear whether Left or Right (both internal)") + def UnknownRelationException = + BiConnectException(": Left or Right unavailable to current module.") + // These are when recursing down aggregate types + def MismatchedVecException = + BiConnectException(": Left and Right are different length Vecs.") + def MissingLeftFieldException(field: String) = + BiConnectException(s".$field: Left Bundle missing field ($field).") + def MissingRightFieldException(field: String) = + BiConnectException(s": Right Bundle missing field ($field).") + def MismatchedException(left: String, right: String) = + BiConnectException(s": Left ($left) and Right ($right) have different types.") + + /** This function is what recursively tries to connect a left and right together + * + * There is some cleverness in the use of internal try-catch to catch exceptions + * during the recursive decent and then rethrow them with extra information added. + * This gives the user a 'path' to where in the connections things went wrong. + */ + def connect(sourceInfo: SourceInfo, left: Data, right: Data, context_mod: Module): Unit = + (left, right) match { + // Handle element case (root case) + case (left_e: Element, right_e: Element) => { + elemConnect(sourceInfo, left_e, right_e, context_mod) + // TODO(twigg): Verify the element-level classes are connectable + } + // Handle Vec case + case (left_v: Vec[Data @unchecked], right_v: Vec[Data @unchecked]) => { + if(left_v.length != right_v.length) { throw MismatchedVecException } + for(idx <- 0 until left_v.length) { + try { + connect(sourceInfo, left_v(idx), right_v(idx), context_mod) + } catch { + case BiConnectException(message) => throw BiConnectException(s"($idx)$message") + } + } + } + // Handle Bundle case + case (left_b: Bundle, right_b: Bundle) => { + // Verify right has no extra fields that left doesn't have + for((field, right_sub) <- right_b.elements) { + if(!left_b.elements.isDefinedAt(field)) throw MissingLeftFieldException(field) + } + // For each field in left, descend with right + for((field, left_sub) <- left_b.elements) { + try { + right_b.elements.get(field) match { + case Some(right_sub) => connect(sourceInfo, left_sub, right_sub, context_mod) + case None => throw MissingRightFieldException(field) + } + } catch { + case BiConnectException(message) => throw BiConnectException(s".$field$message") + } + } + } + // Left and right are different subtypes of Data so fail + case (left, right) => throw MismatchedException(left.toString, right.toString) + } + + // These functions (finally) issue the connection operation + // Issue with right as sink, left as source + private def issueConnectL2R(left: Element, right: Element)(implicit sourceInfo: SourceInfo): Unit = { + pushCommand(Connect(sourceInfo, right.lref, left.ref)) + } + // Issue with left as sink, right as source + private def issueConnectR2L(left: Element, right: Element)(implicit sourceInfo: SourceInfo): Unit = { + pushCommand(Connect(sourceInfo, left.lref, right.ref)) + } + + // This function checks if element-level connection operation allowed. + // Then it either issues it or throws the appropriate exception. + def elemConnect(implicit sourceInfo: SourceInfo, left: Element, right: Element, context_mod: Module): Unit = { + import Direction.{Input, Output} // Using extensively so import these + // If left or right have no location, assume in context module + // This can occur if one of them is a literal, unbound will error previously + val left_mod: Module = left.binding.location.getOrElse(context_mod) + val right_mod: Module = right.binding.location.getOrElse(context_mod) + + val left_direction: Option[Direction] = left.binding.direction + val right_direction: Option[Direction] = right.binding.direction + // None means internal + + // CASE: Context is same module as left node and right node is in a child module + if( (left_mod == context_mod) && + (right_mod._parent.map(_ == context_mod).getOrElse(false)) ) { + // Thus, right node better be a port node and thus have a direction hint + (left_direction, right_direction) match { + // CURRENT MOD CHILD MOD + case (Some(Input), Some(Input)) => issueConnectL2R(left, right) + case (None, Some(Input)) => issueConnectL2R(left, right) + + case (Some(Output), Some(Output)) => issueConnectR2L(left, right) + case (None, Some(Output)) => issueConnectR2L(left, right) + + case (Some(Input), Some(Output)) => throw BothDriversException + case (Some(Output), Some(Input)) => throw NeitherDriverException + case (_, None) => throw UnknownRelationException + } + } + + // CASE: Context is same module as right node and left node is in child module + else if( (right_mod == context_mod) && + (left_mod._parent.map(_ == context_mod).getOrElse(false)) ) { + // Thus, left node better be a port node and thus have a direction hint + (left_direction, right_direction) match { + // CHILD MOD CURRENT MOD + case (Some(Input), Some(Input)) => issueConnectR2L(left, right) + case (Some(Input), None) => issueConnectR2L(left, right) + + case (Some(Output), Some(Output)) => issueConnectL2R(left, right) + case (Some(Output), None) => issueConnectL2R(left, right) + + case (Some(Input), Some(Output)) => throw NeitherDriverException + case (Some(Output), Some(Input)) => throw BothDriversException + case (None, _) => throw UnknownRelationException + } + } + + // CASE: Context is same module that both left node and right node are in + else if( (context_mod == left_mod) && (context_mod == right_mod) ) { + (left_direction, right_direction) match { + // CURRENT MOD CURRENT MOD + case (Some(Input), Some(Output)) => issueConnectL2R(left, right) + case (Some(Input), None) => issueConnectL2R(left, right) + case (None, Some(Output)) => issueConnectL2R(left, right) + + case (Some(Output), Some(Input)) => issueConnectR2L(left, right) + case (Some(Output), None) => issueConnectR2L(left, right) + case (None, Some(Input)) => issueConnectR2L(left, right) + + case (Some(Input), Some(Input)) => throw BothDriversException + case (Some(Output), Some(Output)) => throw NeitherDriverException + case (None, None) => throw UnknownDriverException + } + } + + // CASE: Context is the parent module of both the module containing left node + // and the module containing right node + // Note: This includes case when left and right in same module but in parent + else if( (left_mod._parent.map(_ == context_mod).getOrElse(false)) && + (right_mod._parent.map(_ == context_mod).getOrElse(false)) + ) { + // Thus both nodes must be ports and have a direction hint + (left_direction, right_direction) match { + // CHILD MOD CHILD MOD + case (Some(Input), Some(Output)) => issueConnectR2L(left, right) + case (Some(Output), Some(Input)) => issueConnectL2R(left, right) + + case (Some(Input), Some(Input)) => throw NeitherDriverException + case (Some(Output), Some(Output)) => throw BothDriversException + case (_, None) => throw UnknownRelationException + case (None, _) => throw UnknownRelationException + } + } + + // Not quite sure where left and right are compared to current module + // so just error out + else throw UnknownRelationException + } +} |
