[llvm] [NewPM] Port MachineCombiner to the new pass manager (PR #217279)

[Aiden Grossman via llvm-commits]

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@@ -38,10 +41,11 @@ using namespace llvm;
 
 STATISTIC(NumInstCombined, "Number of machineinst combined");
 
-static cl::opt<unsigned>
-inc_threshold("machine-combiner-inc-threshold", cl::Hidden,
-              cl::desc("Incremental depth computation will be used for basic "
-                       "blocks with more instructions."), cl::init(500));
+static cl::opt<unsigned> inc_threshold(
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boomanaiden154 wrote:

Unrelated formatting hunk?

https://github.com/llvm/llvm-project/pull/217279