[llvm] [Utils][update_mc_test_checks] Support updating round-trip tests. (PR #164425)

[Ivan Kosarev via llvm-commits]

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@@ -24,12 +24,24 @@
 OUTPUT_SKIPPED_RE = re.compile(r"(.text)")
 COMMENT = {"asm": "//", "dasm": "#"}
 
+SUBSTITUTIONS = {
+    "%extract-encodings": "sed -n 's/.*encoding://p'",
+}
+
 
 def invoke_tool(exe, check_rc, cmd_args, testline, verbose=False):
-    if isinstance(cmd_args, list):
-        args = [applySubstitutions(a, substitutions) for a in cmd_args]
-    else:
-        args = cmd_args
+    def apply_substitutions(cmd, exe):
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kosarev wrote:

Makes sense; this way we could also employ `common.getSubstitutions()`, once needed. Updated.

https://github.com/llvm/llvm-project/pull/164425