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7d81062352
Combiners that use C++ code in their "apply" pattern only use that. They never mix it with MIR patterns as that has little added value. This patch restricts C++ apply code so that if C++ is used, we cannot use MIR patterns or builtins with it. Adding this restriction allows us to merge calls to match and apply C++ code together, which in turns makes it so we can just have MatchData variables on the stack. So before, we would have ``` GIM_CheckCxxInsnPredicate // match GIM_CheckCxxInsnPredicate // apply GIR_Done ``` Alongside a massive C++ struct holding the MatchData of all rules possible (which was a big space/perf issue). Now we just have ``` GIR_DoneWithCustomAction ``` And the function being ran just does ``` unsigned SomeMatchData; if (match(SomeMatchData)) apply(SomeMatchData) ``` This approach solves multiple issues in one: - MatchData handling is greatly simplified and more efficient, "don't pay for what you don't use" - We reduce the size of the match table - Calling C++ code has a certain overhead (we need a switch), and this overhead is only paid once now. Handling of C++ code inside PatFrags is unchanged though, that still emits a `GIM_CheckCxxInsnPredicate`. This is completely fine as they can't use MatchDatas.
