[lld] [llvm] [LIT] Use forward slashes in substitutions when LLVM_WINDOWS_PREFER_FORWARD_SLASH is set (PR #179865)

[Aiden Grossman via llvm-commits]

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@@ -3,13 +3,13 @@
 # TODO(boomanaiden154): This sometimes fails, possibly due to buffers not being flushed.
 # ALLOW_RETRIES: 2
 
-# RUN: env LIT_USE_INTERNAL_SHELL=1  not %{lit} -v %{inputs}/shtest-readfile | FileCheck -match-full-lines -DTEMP_PATH=%S%{fs-sep}Inputs%{fs-sep}shtest-readfile%{fs-sep}Output %s
+# RUN: env LIT_USE_INTERNAL_SHELL=1  not %{lit} -v %{inputs}/shtest-readfile | FileCheck -match-full-lines %s
 
 # CHECK: -- Testing: 5 tests{{.*}}
 
 # CHECK-LABEL: FAIL: shtest-readfile :: absolute-paths.txt ({{[^)]*}})
 # CHECK: echo hello
-# CHECK: # executed command: echo '%{readfile:[[TEMP_PATH]]{{[\\\/]}}absolute-paths.txt.tmp}'
+# CHECK: # executed command: echo '%{readfile:{{.*}}absolute-paths.txt.tmp}'
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boomanaiden154 wrote:

Adjusting lit's output I think makes more sense than pessimizing the test fidelity.

https://github.com/llvm/llvm-project/pull/179865