[llvm] [CodeGen] Fix handling dead redefs in finalizeBundle (PR #157427)

[Jay Foad via llvm-commits]

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@@ -8,7 +8,7 @@
 # The arguments to the call must become implicit arguments, because the branch
 # only expects to get 1 explicit operand which is the branch target.
 
-# CHECK:    BUNDLE implicit-def $lr, implicit-def $sp, implicit $sp, implicit $x0, implicit $w1 {
+# CHECK:    BUNDLE implicit-def dead $lr, implicit-def $sp, implicit $sp, implicit $x0, implicit $w1 {
 # CHECK:      BL @_setjmp, csr_aarch64_aapcs, implicit-def $lr, implicit $sp, implicit $x0, implicit $w1, implicit-def dead $lr, implicit $sp, implicit-def $sp
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jayfoad wrote:

This was an unexpected change. I am not sure what it means for `BL` to have both `implicit-def $lr` and `implicit-def dead $lr`.

https://github.com/llvm/llvm-project/pull/157427