[PATCH] D101067: [X86][AMX] Try to hoist AMX shapes' def

[Xiang Zhang via Phabricator via llvm-commits]

xiangzhangllvm added inline comments.


================
Comment at: llvm/lib/Target/X86/X86PreTileConfig.cpp:264
+    if (BBVisitedInfo[&MBB].FirstAMX || BBVisitedInfo[&MBB].HasAMXRegLiveIn)
+      for (auto *Succ : MBB.successors())
+        if (!isLoopBackEdge(Succ, &MBB))
----------------
Looks strange here: All BB followed a AMX BB will be mark HasAMXRegLiveIn, Even BBs after the last BB of using AMX?


================
Comment at: llvm/lib/Target/X86/X86PreTileConfig.cpp:292
+  for (auto &I : ShapeBBs) {
+    // TODO: We can hoist shapes across BBs here.
+    if (BBVisitedInfo[I.first].HasAMXRegLiveIn)
----------------
I think "across BBs" is most common case:

AMX BB0  --> shape def  --> AMX BB1


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D101067/new/

https://reviews.llvm.org/D101067