[UpdateCCTestChecks] Implement --global-value-regex

[jdenny]

Summary

--check-globals activates checks for all global values, and
--global-value-regex filters them. For example, I'd like to use it
in OpenMP offload codegen tests to check only global variables like
.offload_maptypes*.

[jdenny]

Fix the new test for the race discussed at D104714#2841465.

[jdenny]

Ping.

[jdenny]

Ping.

[jdoerfert]

LG

clang/test/utils/update_cc_test_checks/Inputs/global-value-regex.c

+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -emit-llvm -o - %s | FileCheck %s
+
+void foo() {
+  static int i, j;
+}
+void bar() {
+  static int i, j;
+}

clang/test/utils/update_cc_test_checks/Inputs/global-value-regex.c.expected

+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --check-globals --global-value-regex "foo\.."
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -emit-llvm -o - %s | FileCheck %s
+
+//.
+// CHECK: @foo.i = internal global i32 0, align 4
+// CHECK: @foo.j = internal global i32 0, align 4
+//.
+// CHECK-LABEL: @foo(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    ret void
+//
+void foo() {
+  static int i, j;
+}
+// CHECK-LABEL: @bar(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    ret void
+//
+void bar() {
+  static int i, j;
+}

clang/test/utils/update_cc_test_checks/global-value-regex.test

+RUN: rm -rf %t && mkdir %t
+
+# Check --global-value-regex.
+RUN: cp %S/Inputs/global-value-regex.c %t/test.c
+RUN: %update_cc_test_checks %t/test.c --check-globals \
+RUN:   --global-value-regex "foo\.."
+RUN: diff -u %S/Inputs/global-value-regex.c.expected %t/test.c
+
+# Check that the generated directives actually work correctly.
+RUN: cp %S/Inputs/lit.cfg.example %t/lit.cfg
+# Show lit failures while avoiding confusing FileCheck input dump nesting.
+RUN: %lit %t
+# Lit was successful.  Sanity-check the results with deterministic test order.
+RUN: rm %t/.lit_test_times.txt
+RUN: %lit %t 2>&1 | FileCheck %s
+
+CHECK: Testing: 1 tests
+CHECK: PASS: {{.*}} test.c

llvm/utils/UpdateTestChecks/common.py

def parse_commandline_args(parser):
   parser.add_argument('--enable', action='store_true', dest='enabled', default=True,
                        help='Activate CHECK line generation from this point forward')
   parser.add_argument('--disable', action='store_false', dest='enabled',
                       help='Deactivate CHECK line generation from this point forward')
   parser.add_argument('--replace-value-regex', nargs='+', default=[],
                       help='List of regular expressions to replace matching value names')
   parser.add_argument('--prefix-filecheck-ir-name', default='',
                       help='Add a prefix to FileCheck IR value names to avoid conflicts with scripted names')
+  parser.add_argument('--global-value-regex', nargs='+', default=[],
+                      help='List of regular expressions that a global value declaration must match to generate a check (has no effect if checking globals is not enabled)')
   args = parser.parse_args()
-  global _verbose
+  global _verbose, _global_value_regex
   _verbose = args.verbose
+  _global_value_regex = args.global_value_regex
   return args
 
 
 class InputLineInfo(object):
   def __init__(self, line, line_number, args, argv):
     self.line = line
     self.line_number = line_number
     self.args = args
for p in prefix_list:
           break
         if not glob_val_dict[checkprefix]:
           continue
         if nameless_value.check_prefix not in glob_val_dict[checkprefix]:
           continue
         if not glob_val_dict[checkprefix][nameless_value.check_prefix]:
           continue
 
-        output_lines.append(comment_marker + SEPARATOR)
-
+        check_lines = []
         global_vars_seen_before = [key for key in global_vars_seen.keys()]
         for line in glob_val_dict[checkprefix][nameless_value.check_prefix]:
+          if _global_value_regex:
+            matched = False
+            for regex in _global_value_regex:
+              if re.match('^@' + regex + ' = ', line):
+                matched = True
+                break
+            if not matched:
+              continue
           tmp = generalize_check_lines([line], is_analyze, set(), global_vars_seen)
           check_line = '%s %s: %s' % (comment_marker, checkprefix, tmp[0])
+          check_lines.append(check_line)
+        if not check_lines:
+          continue
+
+        output_lines.append(comment_marker + SEPARATOR)
+        for check_line in check_lines:
           output_lines.append(check_line)
+
         printed_prefixes.add((checkprefix, nameless_value.check_prefix))
 
         # Remembe new global variables we have not seen before
         for key in global_vars_seen:
             if key not in global_vars_seen_before:
                 global_vars_seen_dict[checkprefix][key] = global_vars_seen[key]
         break