[BFI] Fix missed BFI updates in MachineSink.

Summary:
This prevents BFI queries on new blocks (from
MachineSinking::GetAllSortedSuccessors) and fixes a bunch of assert failures
under -check-bfi-unknown-block-queries=true.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74511
diff --git a/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp b/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
index d8ea3e0..1168b01 100644
--- a/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
+++ b/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
@@ -247,6 +247,12 @@
   return MBFI->isIrrLoopHeader(MBB);
 }
 
+void MachineBlockFrequencyInfo::setBlockFreq(const MachineBasicBlock *MBB,
+                                             uint64_t Freq) {
+  assert(MBFI && "Expected analysis to be available");
+  MBFI->setBlockFreq(MBB, Freq);
+}
+
 const MachineFunction *MachineBlockFrequencyInfo::getFunction() const {
   return MBFI ? MBFI->getFunction() : nullptr;
 }