[llvm] [MachineSink] Add option for aggressive loop sinking (PR #117247)

[Jeffrey Byrnes via llvm-commits]

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@@ -100,6 +100,12 @@ static cl::opt<bool>
                                 "register spills"),
                        cl::init(false), cl::Hidden);
 
+static cl::opt<bool> AggressivelySinkInstsIntoCycle(
+    "aggressively-sink-insts-to-avoid-spills",
+    cl::desc("Aggressively sink instructions into cycles to avoid "
+             "register spills"),
+    cl::init(false), cl::Hidden);
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jrbyrnes wrote:

The alternative being introducing a transparent optimization? I think this is a useful debug mechanism nonetheless.

https://github.com/llvm/llvm-project/pull/117247