[llvm] Normalize file path to fix problems with different folder separators. (PR #215225)

[James Henderson via llvm-commits]

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@@ -27,19 +27,23 @@
 
 ; RUN: sed -e "s,SRC_COMPDIR,%/p/Inputs,g" %p/Inputs/source-interleave.ll > %t-correct-prefix.ll
 ; RUN: llc -o %t-correct-prefix.o -filetype=obj -mtriple=x86_64-pc-linux %t-correct-prefix.ll
+;; The compilation directory is written with '/' but is normalized, so the
+;; reported path is %p rather than %/p. sys::path::append does not insert a
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jh7370 wrote:

`sys::path::append` usage is an implementation detail that would be best avoided here. I'd replace it with "llvm-objdump does not ..."

https://github.com/llvm/llvm-project/pull/215225