[llvm] [RegAlloc] Fix register's live range for early-clobber (PR #152895)

[via llvm-commits]

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@@ -0,0 +1,102 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=i386-unknown-linux-gnu -start-before=twoaddressinstruction -stop-after=postrapseudos -verify-machineinstrs -o - %s | FileCheck %s
+
+# Test register live range that is split from rematerializing. The live range should
+# start with Slot_EarlyClobber instead of Slot_Register. Machineverifer can check it.
+
+--- |
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LuoYuanke wrote:

Deleting IR section would causing nounwind attribute being lost and CFI instruction is generated in the CHECK section. Is there any way to embed the nounwind information in mir? Anyway I'll delete IR section first.

https://github.com/llvm/llvm-project/pull/152895