From b76612f357eba107f654b4bfc41497be0584ed8c Mon Sep 17 00:00:00 2001
From: Yunsup Lee <yunsup@eecs.berkeley.edu>
Date: Tue, 6 Sep 2016 21:53:55 -0700
Subject: [PATCH] relax contraint on adding AddrMapEntry to AddrMap (#248)

now you can add them in any order.  there's an explicit check at the end to figure out whether there are overlapping regions.
---
 src/main/scala/junctions/addrmap.scala | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/main/scala/junctions/addrmap.scala b/src/main/scala/junctions/addrmap.scala
index 095c2da9..aa1ceac7 100644
--- a/src/main/scala/junctions/addrmap.scala
+++ b/src/main/scala/junctions/addrmap.scala
@@ -77,8 +77,6 @@ class AddrMap(
     var cacheable = true
     for (AddrMapEntry(name, r) <- entriesIn) {
       if (r.start != 0) {
-        val align = BigInt(1) << log2Ceil(r.size)
-        require(r.start >= base, s"region $name base address 0x${r.start.toString(16)} overlaps previous base 0x${base.toString(16)}")
         base = r.start
       } else {
         base = (base + r.size - 1) / r.size * r.size
@@ -121,6 +119,16 @@ class AddrMap(
     }.flatten.sortBy(_.region.start)
   }
 
+  // checks to see whether any MemRange overlaps within this AddrMap
+  flatten.combinations(2) foreach {
+    case (Seq(AddrMapEntry(an, ar), AddrMapEntry(bn, br))) =>
+      val arEnd = ar.start + ar.size
+      val brEnd = br.start + br.size
+      val abOverlaps = ar.start < brEnd && br.start < arEnd
+      require(!abOverlaps,
+        "region $an@0x${ar.start.toString(16)} overlaps region $bn@0x${br.start.toString(16)}")
+  }
+
   def toRange: MemRange = MemRange(start, size, attr)
   def apply(name: String): MemRegion = mapping(name)
   def contains(name: String): Boolean = mapping.contains(name)