SIL/IRGen: analysis of runtime effects for an instruction

Define the possible runtime effects of an instruction in an enum `RuntimeEffect`.
Add a new utility `swift:getRuntimeEffect` to estimate the runtime effects of an instruction.

Also, add a mechanism to validate the correctness of the analysis in IRGen: annotate all runtime functions in RuntimeFunctions.def with the actual effect what the runtime function has or can have. Then check if the effects of emitted runtime functions for an instruction match what `getRuntimeEffect` predicts.
This check is only enabled on demand by defining the CHECK_RUNTIME_EFFECT_ANALYSIS macro in RuntimeEffect.h

Author: eeckstein

include/swift/Runtime/RuntimeFnWrappersGen.h

@@ -16,6 +16,7 @@
 #ifndef SWIFT_RUNTIME_RUNTIMEFNWRAPPERSGEN_H
 #define SWIFT_RUNTIME_RUNTIMEFNWRAPPERSGEN_H
 
+#include "swift/SIL/RuntimeEffect.h"
 #include "llvm/IR/Module.h"
 #include "llvm/ADT/ArrayRef.h"