[PATCH] D24693: [CodeGen] Don't emit lifetime intrinsics for some local variables

Richard Smith via cfe-commits cfe-commits at lists.llvm.org
Mon Sep 26 18:43:27 PDT 2016

rsmith added a comment.

Before we start with heroics here, we should consider whether the LLVM intrinsics are actually specified the right way. The current specification does the wrong thing for even trivial cases, such as a variable declared within a loop, so there's some impedance mismatch between the specification and how Clang uses the intrinsics, even with this patch applied. Can we get some clarity on how these intrinsics are *actually* supposed to work? (Is it permitted to have multiple start+end regions for the same alloca, or do we need to suppress them inside loops too? What happens if we have multiple starts but no ends?)


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