commit 0e3e242209c7f84009c9d88fe52982f8ba21c68b
author Hiroshi Yamauchi <yamauchi@google.com> Wed Feb 12 14:55:53 2020 -0800
committer Hiroshi Yamauchi <yamauchi@google.com> Fri Feb 21 09:50:54 2020 -0800
tree 41c55e690ecb5052b34f4da79c4424be646ff031
parent e4df934ca7b408cfb52531016198545a8d50f41a

[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

llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp

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;
 }

llvm/lib/CodeGen/MachineSink.cpp

diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
index ab9a713..ac342ba 100644
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -91,7 +91,7 @@
     MachineDominatorTree *DT;      // Machine dominator tree
     MachinePostDominatorTree *PDT; // Machine post dominator tree
     MachineLoopInfo *LI;
-    const MachineBlockFrequencyInfo *MBFI;
+    MachineBlockFrequencyInfo *MBFI;
     const MachineBranchProbabilityInfo *MBPI;
     AliasAnalysis *AA;
 
@@ -351,6 +351,11 @@
                           << printMBBReference(*Pair.first) << " -- "
                           << printMBBReference(*NewSucc) << " -- "
                           << printMBBReference(*Pair.second) << '\n');
+        if (MBFI) {
+          auto NewSuccFreq = MBFI->getBlockFreq(Pair.first) *
+                             MBPI->getEdgeProbability(Pair.first, NewSucc);
+          MBFI->setBlockFreq(NewSucc, NewSuccFreq.getFrequency());
+        }
         MadeChange = true;
         ++NumSplit;
       } else