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The previous branch hint instrumentation logic would introduce a scratch local to hold the condition so it could be passed into both the logging function and the original branching instruction. The de-instrumentation pass would then need to find this local and attempt to undo the data flow change. Simplify all of this by having the logging function return the condition value so it can interpose between the condition and the branch without any new locals. De-instrumentation can now just replace the call to the log function with its condition parameter. To allow further simplification, also change the order of parameters to the logging function so the condition value is the first parameter. This ensures that we don't need to introduce a scratch local even when the condition is a `pop`, because the pop will remain the leftmost leaf expression in the catch body.
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The previous branch hint instrumentation logic would introduce a scratch local to hold the condition so it could be passed into both the logging function and the original branching instruction. The de-instrumentation pass would then need to find this local and attempt to undo the data flow change. Simplify all of this by having the logging function return the condition value so it can interpose between the condition and the branch without any new locals. De-instrumentation can now just replace the call to the log function with its condition parameter.
To allow further simplification, also change the order of parameters to the logging function so the condition value is the first parameter. This ensures that we don't need to introduce a scratch local even when the condition is a
pop, because the pop will remain the leftmost leaf expression in the catch body.