[PATCH] D11662: Filter cold blocks off the loop chain when profile data is available.

[Cong Hou]

congh added inline comments.

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Comment at: lib/CodeGen/MachineBlockPlacement.cpp:826
@@ +825,3 @@
+    // We use the threshold 20% here to filter cold blocks.
+    const unsigned LoopToColdBBRatio = 5;
+    for (MachineBasicBlock *LoopBB : L.getBlocks()) {
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davidxl wrote:
> Try to avoid hard-coding parameter like this.
Should I make it a global constant variable or an option? The other 20% probability used in selectBestSuccessor() is also hard-coded and we could use the same variable to replace them.


http://reviews.llvm.org/D11662