LiveRange: Replace a creative vector erase loop with std::remove_if.

I didn't see this so far because it scans backwards, but that doesn't
make it any less quadratic. NFC.

llvm-svn: 230863

1 files changed, 3 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/LiveInterval.cpp b/llvm/lib/CodeGen/LiveInterval.cpp
index fd7516dfd47..d60b0b1a504 100644
--- a/llvm/lib/CodeGen/LiveInterval.cpp
+++ b/llvm/lib/CodeGen/LiveInterval.cpp
@@ -567,13 +567,9 @@ void LiveRange::removeSegment(SlotIndex Start, SlotIndex End,
 /// Also remove the value# from value# list.
 void LiveRange::removeValNo(VNInfo *ValNo) {
   if (empty()) return;
-  iterator I = end();
-  iterator E = begin();
-  do {
-    --I;
-    if (I->valno == ValNo)
-      segments.erase(I);
-  } while (I != E);
+  segments.erase(std::remove_if(begin(), end(), [ValNo](const Segment &S) {
+    return S.valno == ValNo;
+  }), end());
   // Now that ValNo is dead, remove it.
   markValNoForDeletion(ValNo);
 }