Fix handling of the llvm.eh.typeid.for intrinsic #177
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We use IntrinsicLowering to turn a number of supported intrinsics into code or library calls that we can instrument. This transformation is expected to preserve code semantics. However, IntrinsicLowering handles llvm.eh.typeid.for by inserting a dummy value of constant 1, which changes code semantics in many cases (except when 1 happens to be the expected type ID). This commit makes the compiler stop using IntrinsicLowering for llvm.eh.typeid.for; instead, we treat the intrinsic's result as a constant. Fixes eng/das/fuzz/symcc#23.
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We use
IntrinsicLoweringto turn a number of supported intrinsics into code or library calls that we can instrument. This transformation is expected to preserve code semantics. However,IntrinsicLoweringhandlesllvm.eh.typeid.forby inserting a dummy value of constant 1, which changes code semantics in many cases (except when 1 happens to be the expected type ID).This commit makes the compiler stop using
IntrinsicLoweringforllvm.eh.typeid.for; instead, we treat the intrinsic's result as a constant.Fixes eng/das/fuzz/symcc#23.