Recommit r231168: unique_ptrify LiveRange::segmentSet

GCC 4.7's libstdc++ doesn't have std::map::emplace, but it does have
std::unordered_map::emplace, and the use case here doesn't appear to
need ordering. The container has been changed in a separate/precursor
patch, and now this patch should hopefully build cleanly even with
GCC 4.7.

& then I realized the order of the container did matter, so extra
handling of ordering was added in r231189.

Original commit message:
This makes LiveRange non-copyable, and LiveInterval is already
non-movable (due to the explicit dtor), so now it's non-copyable and
non-movable.

Fix the one case where we were relying on the (deprecated in C++11)
implicit copy ctor of LiveInterval (which happened to work because the
ctor created an object with a null segmentSet, so double-deleting the
null pointer was fine).

llvm-svn: 231192

1 files changed, 4 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/LiveStackAnalysis.cpp b/llvm/lib/CodeGen/LiveStackAnalysis.cpp
index 8a6ac251ab2..5c9c679e97b 100644
--- a/llvm/lib/CodeGen/LiveStackAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveStackAnalysis.cpp
@@ -61,8 +61,10 @@ LiveStacks::getOrCreateInterval(int Slot, const TargetRegisterClass *RC) {
   assert(Slot >= 0 && "Spill slot indice must be >= 0");
   SS2IntervalMap::iterator I = S2IMap.find(Slot);
   if (I == S2IMap.end()) {
-    I = S2IMap.insert(I, std::make_pair(Slot,
-            LiveInterval(TargetRegisterInfo::index2StackSlot(Slot), 0.0F)));
+    I = S2IMap.emplace(std::piecewise_construct, std::forward_as_tuple(Slot),
+                       std::forward_as_tuple(
+                           TargetRegisterInfo::index2StackSlot(Slot), 0.0F))
+            .first;
     S2RCMap.insert(std::make_pair(Slot, RC));
   } else {
     // Use the largest common subclass register class.