[lit] [Windows] Print exit codes > 255 as hex too

[mstorsjo]

Summary

891bb4872c8098f8a851a92e989af3252b46f5ad made negative exit codes
be printed as hex, which makes it easier to recognize e.g.
0xC0000005 instead of -1073741819. However, current Python versions
(at least the ones I'm using) seem to end up with positive unsigned
return codes, so that again ends up printed as 3221225477.

Print any return code over 255 as a hexadecimal number instead.

[rnk]

I agree, this would be super helpful.

llvm/utils/lit/lit/TestRunner.py

for i,result in enumerate(results):
             out += '# command stderr:\n%s\n' % (result.stderr,)
         if not result.stdout.strip() and not result.stderr.strip():
             out += "note: command had no output on stdout or stderr\n"
 
         # Show the error conditions:
         if result.exitCode != 0:
             # On Windows, a negative exit code indicates a signal, and those are
             # easier to recognize or look up if we print them in hex.
-            if litConfig.isWindows and result.exitCode < 0:
+            if litConfig.isWindows and (result.exitCode < 0 or result.exitCode > 255):
                 codeStr = hex(int(result.exitCode & 0xFFFFFFFF)).rstrip("L")
             else:
                 codeStr = str(result.exitCode)
             out += "error: command failed with exit status: %s\n" % (
                 codeStr,)
         if litConfig.maxIndividualTestTime > 0 and result.timeoutReached:
             out += 'error: command reached timeout: %s\n' % (
                 str(result.timeoutReached),)