[lld] Use lit's shell to run tests on Windows by default

It's a lot faster than bash.

Also use FileCheck instead of grep to search through a binary file.
Cygwin's grep isn't working here for unknown reasons that probably
aren't worth investigating.

llvm-svn: 237834

lld/test/lit.cfg

@@ -14,12 +14,22 @@ import lit.util
 # name: The name of this test suite.
 config.name = 'lld'
 
+# Choose between lit's internal shell pipeline runner and a real shell.  If
+# LIT_USE_INTERNAL_SHELL is in the environment, we use that as an override.
+use_lit_shell = os.environ.get("LIT_USE_INTERNAL_SHELL")
+if use_lit_shell:
+    # 0 is external, "" is default, and everything else is internal.
+    execute_external = (use_lit_shell == "0")
+else:
+    # Otherwise we default to internal on Windows and external elsewhere, as
+    # bash on Windows is usually very slow.
+    execute_external = (not sys.platform in ['win32'])
+
+
 # testFormat: The test format to use to interpret tests.
 #
 # For now we require '&&' between commands, until they get globally killed and
 # the test runner updated.
-execute_external = (platform.system() != 'Windows'
-                    or lit_config.getBashPath() not in [None, ""])
 config.test_format = lit.formats.ShTest(execute_external)
 
 # suffixes: A list of file extensions to treat as test files.

lld/test/pecoff/resource.test

@@ -6,7 +6,9 @@
 # RUN:   -- %t.obj %p/Inputs/resource.res
 
 # Check if the binary contains UTF-16LE string "Hello" copied from resource.res.
-# RUN: cat %t.exe | grep 'H.e.l.l.o'
+# RUN: FileCheck --check-prefix=EXE %s < %t.exe
+
+EXE: {{H.e.l.l.o}}
 
 # RUN: lld -flavor link /out:%t.exe /subsystem:console /entry:start /opt:noref \
 # RUN:   /manifest:embed -- %t.obj %p/Inputs/resource.res