[llvm] [DWARF] Emit a worst-case prologue_end flag for pathological inputs (PR #107849)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -0,0 +1,134 @@
+# RUN: llc %s -start-before=livedebugvalues -o - | \
+# RUN:     FileCheck %s --implicit-check-not=prologue_end
+#
+## When picking a "backup" location of the first non-trivial instruction in
+## a function, don't select a location outside of the entry block. We have to
+## give it the functions scope-line, and installing that outside of the entry
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OCHyams wrote:

nit: functions -> function's

https://github.com/llvm/llvm-project/pull/107849