[llvm] [CodeLayout] Size-aware machine block placement (PR #109711)

[Kyungwoo Lee via llvm-commits]

================
@@ -3604,24 +3624,48 @@ void MachineBlockPlacement::applyExtTsp() {
     // not see a perf improvement with the exact block sizes.
     auto NonDbgInsts =
         instructionsWithoutDebug(MBB.instr_begin(), MBB.instr_end());
-    int NumInsts = std::distance(NonDbgInsts.begin(), NonDbgInsts.end());
+    size_t NumInsts = std::distance(NonDbgInsts.begin(), NonDbgInsts.end());
     BlockSizes[BlockIndex[&MBB]] = 4 * NumInsts;
     // Getting jump frequencies.
-    for (MachineBasicBlock *Succ : MBB.successors()) {
-      auto EP = MBPI->getEdgeProbability(&MBB, Succ);
-      BlockFrequency JumpFreq = BlockFreq * EP;
-      JumpCounts.push_back(
-          {BlockIndex[&MBB], BlockIndex[Succ], JumpFreq.getFrequency()});
+
+    if (!OptForSize) {
----------------
kyulee-com wrote:

Could we swap the conditions in the if/else statement?
```suggestion
    if (OptForSize) {
...
```

https://github.com/llvm/llvm-project/pull/109711