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tilelink2 Fuzzer: work around for firrtl/verilator performance issue

Big Vec()s cause very slow compilation.
This commit is contained in:
Wesley W. Terpstra 2016-09-22 11:33:40 -07:00
parent 1e7480b6fc
commit ed038678ef
2 changed files with 16 additions and 11 deletions

View File

@ -14,23 +14,22 @@ class IDMapGenerator(numIds: Int) extends Module {
} }
// True indicates that the id is available // True indicates that the id is available
val bitmap = RegInit(Vec.fill(numIds){Bool(true)}) val bitmap = RegInit(UInt((BigInt(1) << numIds) - 1, width = numIds))
io.free.ready := Bool(true) io.free.ready := Bool(true)
assert (!io.free.valid || !bitmap(io.free.bits)) // No double freeing assert (!io.free.valid || !bitmap(io.free.bits)) // No double freeing
val mask = bitmap.scanLeft(Bool(false))(_||_).init val select = ~(highOR(bitmap) << 1) & bitmap
val select = mask zip bitmap map { case(m,b) => !m && b }
io.alloc.bits := OHToUInt(select) io.alloc.bits := OHToUInt(select)
io.alloc.valid := bitmap.reduce(_||_) io.alloc.valid := bitmap.orR()
when (io.alloc.fire()) { val clr = Wire(init = UInt(0, width = numIds))
bitmap(io.alloc.bits) := Bool(false) when (io.alloc.fire()) { clr := UIntToOH(io.alloc.bits) }
}
when (io.free.fire()) { val set = Wire(init = UInt(0, width = numIds))
bitmap(io.free.bits) := Bool(true) when (io.free.fire()) { set := UIntToOH(io.free.bits) }
}
bitmap := (bitmap & ~clr) | set
} }
object LFSR64 object LFSR64

View File

@ -10,6 +10,12 @@ package object tilelink2
def OH1ToUInt(x: UInt) = OHToUInt((x << 1 | UInt(1)) ^ x) def OH1ToUInt(x: UInt) = OHToUInt((x << 1 | UInt(1)) ^ x)
def UIntToOH1(x: UInt, width: Int) = ~(SInt(-1, width=width).asUInt << x)(width-1, 0) def UIntToOH1(x: UInt, width: Int) = ~(SInt(-1, width=width).asUInt << x)(width-1, 0)
def trailingZeros(x: Int) = if (x > 0) Some(log2Ceil(x & -x)) else None def trailingZeros(x: Int) = if (x > 0) Some(log2Ceil(x & -x)) else None
def highOR(x: UInt) = {
val w = x.getWidth
def helper(s: Int, x: UInt): UInt =
if (s >= w) x else helper(s+s, x | x << s)
helper(1, x)
}
def sourceLine(sourceInfo: SourceInfo, prefix: String = " (", suffix: String = ")") = sourceInfo match { def sourceLine(sourceInfo: SourceInfo, prefix: String = " (", suffix: String = ")") = sourceInfo match {
case SourceLine(filename, line, col) => s"$prefix$filename:$line:$col$suffix" case SourceLine(filename, line, col) => s"$prefix$filename:$line:$col$suffix"