[clang] [llvm] [InstrPGO] Instrument sampling profile based cold function (PR #109837)

[via cfe-commits]

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@@ -319,6 +319,29 @@ static cl::opt<unsigned> PGOFunctionCriticalEdgeThreshold(
     cl::desc("Do not instrument functions with the number of critical edges "
              " greater than this threshold."));
 
+static cl::opt<uint64_t> ColdFuncCoverageMaxEntryCount(
+    "cold-function-coverage-max-entry-count", cl::init(0), cl::Hidden,
+    cl::desc("When enabling cold function coverage instrumentation, skip "
+             "instrumenting the function whose entry count is above the given "
+             "value"));
+
+static cl::opt<InstrColdFuncCovMode> InstrumentColdFunctionCoverageMode(
+    "instrument-cold-function-coverage-mode",
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WenleiHe wrote:

Practically do you think we will end up using more than two modes? If not, how about simplify this with `pgo-treat-unknown-as-cold`/`pgo-treat-unprofiled-as-cold`?

https://github.com/llvm/llvm-project/pull/109837