[build-script] On buildbots, pass in the -v command into lit instead of -sv.

This enables you to know what tests actually ran instead of just the number of
tests that ran. This helps identify:

1. Tests that are not running, but /should/ be running.
2. Tests that are XFAILED or DISABLED but should not be.

Author: gottesmm

utils/build-presets.ini

@@ -26,6 +26,7 @@ tvos
 watchos
 test
 validation-test
+lit-args=-v
 
 dash-dash
 
@@ -201,6 +202,7 @@ skip-test-watchos-host
 [preset: buildbot_incremental_base]
 test
 validation-test
+lit-args=-v
 
 dash-dash
 
@@ -449,6 +451,7 @@ build-subdir=buildbot_incremental_llvmonly
 release-debug
 assertions
 test=0
+lit-args=-v
 
 dash-dash
 
@@ -613,6 +616,7 @@ test
 validation-test
 long-test
 foundation
+lit-args=-v
 
 dash-dash
 
@@ -672,6 +676,7 @@ assertions
 release
 test
 validation-test
+lit-args=-v
 
 dash-dash
 

utils/build-script

@@ -796,6 +796,9 @@ class BuildScriptInvocation(object):
         if args.dry_run:
             impl_args += ["--dry-run"]
 
+        if args.lit_args:
+            impl_args += ["--llvm-lit-args=%s" % args.lit_args]
+
         # Compute the set of host-specific variables, which we pass through to
         # the build script via environment variables.
         host_specific_variables = self.compute_host_specific_variables()
@@ -1947,6 +1950,12 @@ details of the setups of other systems or automated environments.""")
         "--skip-test-optimized",
         action=arguments.action.unavailable)
 
+    parser.add_argument(
+        "--lit-args",
+        help="lit args to use when testing",
+        metavar="LITARGS",
+        default="-sv")
+
     args = migration.parse_args(parser, sys.argv[1:])
 
     if args.build_script_impl_args:

utils/build-script-impl

@@ -225,6 +225,7 @@ KNOWN_SETTINGS=(
     # TODO: Remove this some time later.
     user-config-args            ""               "**Renamed to --extra-cmake-options**: User-supplied arguments to cmake when used to do configuration."
     only-execute                       "all"     "Only execute the named action (see implementation)"
+    llvm-lit-args                      ""        "If set, override the lit args passed to LLVM"
 )
 
 # Centralized access point for traced command invocation.
@@ -651,6 +652,15 @@ function set_build_options_for_host() {
         -DSWIFT_HOST_VARIANT_SDK="${SWIFT_HOST_VARIANT_SDK}"
         -DSWIFT_HOST_VARIANT_ARCH="${SWIFT_HOST_VARIANT_ARCH}"
     )
+
+    if [[ "${LLVM_LIT_ARGS}" ]]; then
+        llvm_cmake_options+=(
+            -DLLVM_LIT_ARGS="${LLVM_LIT_ARGS}"
+        )
+        swift_cmake_options+=(
+            -DLLVM_LIT_ARGS="${LLVM_LIT_ARGS}"
+        )
+    fi
 }
 
 function configure_default_options() {