Refactoring lib/IR/AutoUpgrade.cpp file.

[aymanmusa]

Bugzilla Link	31034
Version	trunk
OS	All
CC	@aymanmusa,@topperc,@RKSimon,@rotateright,@ZviRackover

Extended Description

llvm::UpgradeIntrinsicCall() function in lib/IR/AutoUpgrade.cpp source file checks if the IR includes an old intrinsic and replaces it with the upgraded IR.

The checks are implemented by a long "if else" sequence which some compilers complain about when it gets too long (For example, Microsoft C++ compiler will accept up to 127 if-else statements).

A refactoring to this "structure" should be considered as an effort to reduce the use of llvm x86 specific intrinsics is being initiated, and as a result many new cases will be added to the same control flow in the future.

[xgupta]

Hi @aymanmusa,
what is your suggestion to refractor this file? Create a lookup table with struct and then iterate over the lookup table with a for loop?

[nikic]

Going to close this as a non-goal. The intrinsic auto-upgrade has already been split up into various helper functions over time, and can be split further as needed. There is no need to change anything about the general approach.