[clang] [Clang] Add fake use emission to Clang with -fextend-lifetimes (PR #110102)

[Jeremy Morse via cfe-commits]

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@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 %s -O2 -emit-llvm -fextend-lifetimes -fcxx-exceptions -fexceptions -o - | FileCheck %s
+// REQUIRES: x86-registered-target
+// This test checks that the fake_use concept works with exception handling and that we
+// can handle the __int128 data type.
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jmorse wrote:

IMO this can be more direct: "Test that fake uses of values defined in exception blocks..." etc. "... and that we emit fake uses of int128s". The future reader adding some subtle semantic shift is going to want to know the exact behaviour demanded.

https://github.com/llvm/llvm-project/pull/110102