Azure & Shippable: Upgrade LDC-LLVM to v9.0.0

utils/FileCheck-9.0.cpp

@@ -0,0 +1,651 @@
+//===- FileCheck.cpp - Check that File's Contents match what is expected --===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// FileCheck does a line-by line check of a file that validates whether it
+// contains the expected content.  This is useful for regression tests etc.
+//
+// This program exits with an exit status of 2 on error, exit status of 0 if
+// the file matched the expected contents, and exit status of 1 if it did not
+// contain the expected contents.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/Process.h"
+#include "llvm/Support/WithColor.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/FileCheck.h"
+#include <cmath>
+using namespace llvm;
+
+static cl::opt<std::string>
+    CheckFilename(cl::Positional, cl::desc("<check-file>"), cl::Optional);
+
+static cl::opt<std::string>
+    InputFilename("input-file", cl::desc("File to check (defaults to stdin)"),
+                  cl::init("-"), cl::value_desc("filename"));
+
+static cl::list<std::string> CheckPrefixes(
+    "check-prefix",
+    cl::desc("Prefix to use from check file (defaults to 'CHECK')"));
+static cl::alias CheckPrefixesAlias(
+    "check-prefixes", cl::aliasopt(CheckPrefixes), cl::CommaSeparated,
+    cl::NotHidden,
+    cl::desc(
+        "Alias for -check-prefix permitting multiple comma separated values"));
+
+static cl::opt<bool> NoCanonicalizeWhiteSpace(
+    "strict-whitespace",
+    cl::desc("Do not treat all horizontal whitespace as equivalent"));
+
+static cl::list<std::string> ImplicitCheckNot(
+    "implicit-check-not",
+    cl::desc("Add an implicit negative check with this pattern to every\n"
+             "positive check. This can be used to ensure that no instances of\n"
+             "this pattern occur which are not matched by a positive pattern"),
+    cl::value_desc("pattern"));
+
+static cl::list<std::string>
+    GlobalDefines("D", cl::AlwaysPrefix,
+                  cl::desc("Define a variable to be used in capture patterns."),
+                  cl::value_desc("VAR=VALUE"));
+
+static cl::opt<bool> AllowEmptyInput(
+    "allow-empty", cl::init(false),
+    cl::desc("Allow the input file to be empty. This is useful when making\n"
+             "checks that some error message does not occur, for example."));
+
+static cl::opt<bool> MatchFullLines(
+    "match-full-lines", cl::init(false),
+    cl::desc("Require all positive matches to cover an entire input line.\n"
+             "Allows leading and trailing whitespace if --strict-whitespace\n"
+             "is not also passed."));
+
+static cl::opt<bool> EnableVarScope(
+    "enable-var-scope", cl::init(false),
+    cl::desc("Enables scope for regex variables. Variables with names that\n"
+             "do not start with '$' will be reset at the beginning of\n"
+             "each CHECK-LABEL block."));
+
+static cl::opt<bool> AllowDeprecatedDagOverlap(
+    "allow-deprecated-dag-overlap", cl::init(false),
+    cl::desc("Enable overlapping among matches in a group of consecutive\n"
+             "CHECK-DAG directives.  This option is deprecated and is only\n"
+             "provided for convenience as old tests are migrated to the new\n"
+             "non-overlapping CHECK-DAG implementation.\n"));
+
+static cl::opt<bool> Verbose(
+    "v", cl::init(false),
+    cl::desc("Print directive pattern matches, or add them to the input dump\n"
+             "if enabled.\n"));
+
+static cl::opt<bool> VerboseVerbose(
+    "vv", cl::init(false),
+    cl::desc("Print information helpful in diagnosing internal FileCheck\n"
+             "issues, or add it to the input dump if enabled.  Implies\n"
+             "-v.\n"));
+static const char * DumpInputEnv = "FILECHECK_DUMP_INPUT_ON_FAILURE";
+
+static cl::opt<bool> DumpInputOnFailure(
+    "dump-input-on-failure", cl::init(std::getenv(DumpInputEnv)),
+    cl::desc("Dump original input to stderr before failing.\n"
+             "The value can be also controlled using\n"
+             "FILECHECK_DUMP_INPUT_ON_FAILURE environment variable.\n"
+             "This option is deprecated in favor of -dump-input=fail.\n"));
+
+enum DumpInputValue {
+  DumpInputDefault,
+  DumpInputHelp,
+  DumpInputNever,
+  DumpInputFail,
+  DumpInputAlways
+};
+
+static cl::opt<DumpInputValue> DumpInput(
+    "dump-input", cl::init(DumpInputDefault),
+    cl::desc("Dump input to stderr, adding annotations representing\n"
+             " currently enabled diagnostics\n"),
+    cl::value_desc("mode"),
+    cl::values(clEnumValN(DumpInputHelp, "help",
+                          "Explain dump format and quit"),
+               clEnumValN(DumpInputNever, "never", "Never dump input"),
+               clEnumValN(DumpInputFail, "fail", "Dump input on failure"),
+               clEnumValN(DumpInputAlways, "always", "Always dump input")));
+
+typedef cl::list<std::string>::const_iterator prefix_iterator;
+
+
+
+
+
+
+
+static void DumpCommandLine(int argc, char **argv) {
+  errs() << "FileCheck command line: ";
+  for (int I = 0; I < argc; I++)
+    errs() << " " << argv[I];
+  errs() << "\n";
+}
+
+struct MarkerStyle {
+  /// The starting char (before tildes) for marking the line.
+  char Lead;
+  /// What color to use for this annotation.
+  raw_ostream::Colors Color;
+  /// A note to follow the marker, or empty string if none.
+  std::string Note;
+  MarkerStyle() {}
+  MarkerStyle(char Lead, raw_ostream::Colors Color,
+              const std::string &Note = "")
+      : Lead(Lead), Color(Color), Note(Note) {}
+};
+
+static MarkerStyle GetMarker(FileCheckDiag::MatchType MatchTy) {
+  switch (MatchTy) {
+  case FileCheckDiag::MatchFoundAndExpected:
+    return MarkerStyle('^', raw_ostream::GREEN);
+  case FileCheckDiag::MatchFoundButExcluded:
+    return MarkerStyle('!', raw_ostream::RED, "error: no match expected");
+  case FileCheckDiag::MatchFoundButWrongLine:
+    return MarkerStyle('!', raw_ostream::RED, "error: match on wrong line");
+  case FileCheckDiag::MatchFoundButDiscarded:
+    return MarkerStyle('!', raw_ostream::CYAN,
+                       "discard: overlaps earlier match");
+  case FileCheckDiag::MatchNoneAndExcluded:
+    return MarkerStyle('X', raw_ostream::GREEN);
+  case FileCheckDiag::MatchNoneButExpected:
+    return MarkerStyle('X', raw_ostream::RED, "error: no match found");
+  case FileCheckDiag::MatchFuzzy:
+    return MarkerStyle('?', raw_ostream::MAGENTA, "possible intended match");
+  }
+  llvm_unreachable_internal("unexpected match type");
+}
+
+static void DumpInputAnnotationHelp(raw_ostream &OS) {
+  OS << "The following description was requested by -dump-input=help to\n"
+     << "explain the input annotations printed by -dump-input=always and\n"
+     << "-dump-input=fail:\n\n";
+
+  // Labels for input lines.
+  OS << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "L:";
+  OS << "     labels line number L of the input file\n";
+
+  // Labels for annotation lines.
+  OS << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "T:L";
+  OS << "    labels the only match result for a pattern of type T from "
+     << "line L of\n"
+     << "           the check file\n";
+  OS << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "T:L'N";
+  OS << "  labels the Nth match result for a pattern of type T from line "
+     << "L of\n"
+     << "           the check file\n";
+
+  // Markers on annotation lines.
+  OS << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "^~~";
+  OS << "    marks good match (reported if -v)\n"
+     << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "!~~";
+  OS << "    marks bad match, such as:\n"
+     << "           - CHECK-NEXT on same line as previous match (error)\n"
+     << "           - CHECK-NOT found (error)\n"
+     << "           - CHECK-DAG overlapping match (discarded, reported if "
+     << "-vv)\n"
+     << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "X~~";
+  OS << "    marks search range when no match is found, such as:\n"
+     << "           - CHECK-NEXT not found (error)\n"
+     << "           - CHECK-NOT not found (success, reported if -vv)\n"
+     << "           - CHECK-DAG not found after discarded matches (error)\n"
+     << "  - ";
+  WithColor(OS, raw_ostream::SAVEDCOLOR, true) << "?";
+  OS << "      marks fuzzy match when no match is found\n";
+
+  // Colors.
+  OS << "  - colors ";
+  WithColor(OS, raw_ostream::GREEN, true) << "success";
+  OS << ", ";
+  WithColor(OS, raw_ostream::RED, true) << "error";
+  OS << ", ";
+  WithColor(OS, raw_ostream::MAGENTA, true) << "fuzzy match";
+  OS << ", ";
+  WithColor(OS, raw_ostream::CYAN, true, false) << "discarded match";
+  OS << ", ";
+  WithColor(OS, raw_ostream::CYAN, true, true) << "unmatched input";
+  OS << "\n\n"
+     << "If you are not seeing color above or in input dumps, try: -color\n";
+}
+
+/// An annotation for a single input line.
+struct InputAnnotation {
+  /// The check file line (one-origin indexing) where the directive that
+  /// produced this annotation is located.
+  unsigned CheckLine;
+  /// The index of the match result for this check.
+  unsigned CheckDiagIndex;
+  /// The label for this annotation.
+  std::string Label;
+  /// What input line (one-origin indexing) this annotation marks.  This might
+  /// be different from the starting line of the original diagnostic if this is
+  /// a non-initial fragment of a diagnostic that has been broken across
+  /// multiple lines.
+  unsigned InputLine;
+  /// The column range (one-origin indexing, open end) in which to to mark the
+  /// input line.  If InputEndCol is UINT_MAX, treat it as the last column
+  /// before the newline.
+  unsigned InputStartCol, InputEndCol;
+  /// The marker to use.
+  MarkerStyle Marker;
+  /// Whether this annotation represents a good match for an expected pattern.
+  bool FoundAndExpectedMatch;
+};
+
+/// Get an abbreviation for the check type.
+std::string GetCheckTypeAbbreviation(Check::FileCheckType Ty) {
+  switch (Ty) {
+  case Check::CheckPlain:
+    if (Ty.getCount() > 1)
+      return "count";
+    return "check";
+  case Check::CheckNext:
+    return "next";
+  case Check::CheckSame:
+    return "same";
+  case Check::CheckNot:
+    return "not";
+  case Check::CheckDAG:
+    return "dag";
+  case Check::CheckLabel:
+    return "label";
+  case Check::CheckEmpty:
+    return "empty";
+  case Check::CheckEOF:
+    return "eof";
+  case Check::CheckBadNot:
+    return "bad-not";
+  case Check::CheckBadCount:
+    return "bad-count";
+  case Check::CheckNone:
+    llvm_unreachable("invalid FileCheckType");
+  }
+  llvm_unreachable("unknown FileCheckType");
+}
+
+static void BuildInputAnnotations(const std::vector<FileCheckDiag> &Diags,
+                                  std::vector<InputAnnotation> &Annotations,
+                                  unsigned &LabelWidth) {
+  // How many diagnostics has the current check seen so far?
+  unsigned CheckDiagCount = 0;
+  // What's the widest label?
+  LabelWidth = 0;
+  for (auto DiagItr = Diags.begin(), DiagEnd = Diags.end(); DiagItr != DiagEnd;
+       ++DiagItr) {
+    InputAnnotation A;
+
+    // Build label, which uniquely identifies this check result.
+    A.CheckLine = DiagItr->CheckLine;
+    llvm::raw_string_ostream Label(A.Label);
+    Label << GetCheckTypeAbbreviation(DiagItr->CheckTy) << ":"
+          << DiagItr->CheckLine;
+    A.CheckDiagIndex = UINT_MAX;
+    auto DiagNext = std::next(DiagItr);
+    if (DiagNext != DiagEnd && DiagItr->CheckTy == DiagNext->CheckTy &&
+        DiagItr->CheckLine == DiagNext->CheckLine)
+      A.CheckDiagIndex = CheckDiagCount++;
+    else if (CheckDiagCount) {
+      A.CheckDiagIndex = CheckDiagCount;
+      CheckDiagCount = 0;
+    }
+    if (A.CheckDiagIndex != UINT_MAX)
+      Label << "'" << A.CheckDiagIndex;
+    else
+      A.CheckDiagIndex = 0;
+    Label.flush();
+    LabelWidth = std::max((std::string::size_type)LabelWidth, A.Label.size());
+
+    MarkerStyle Marker = GetMarker(DiagItr->MatchTy);
+    A.Marker = Marker;
+    A.FoundAndExpectedMatch =
+        DiagItr->MatchTy == FileCheckDiag::MatchFoundAndExpected;
+
+    // Compute the mark location, and break annotation into multiple
+    // annotations if it spans multiple lines.
+    A.InputLine = DiagItr->InputStartLine;
+    A.InputStartCol = DiagItr->InputStartCol;
+    if (DiagItr->InputStartLine == DiagItr->InputEndLine) {
+      // Sometimes ranges are empty in order to indicate a specific point, but
+      // that would mean nothing would be marked, so adjust the range to
+      // include the following character.
+      A.InputEndCol =
+          std::max(DiagItr->InputStartCol + 1, DiagItr->InputEndCol);
+      Annotations.push_back(A);
+    } else {
+      assert(DiagItr->InputStartLine < DiagItr->InputEndLine &&
+             "expected input range not to be inverted");
+      A.InputEndCol = UINT_MAX;
+      A.Marker.Note = "";
+      Annotations.push_back(A);
+      for (unsigned L = DiagItr->InputStartLine + 1, E = DiagItr->InputEndLine;
+           L <= E; ++L) {
+        // If a range ends before the first column on a line, then it has no
+        // characters on that line, so there's nothing to render.
+        if (DiagItr->InputEndCol == 1 && L == E) {
+          Annotations.back().Marker.Note = Marker.Note;
+          break;
+        }
+        InputAnnotation B;
+        B.CheckLine = A.CheckLine;
+        B.CheckDiagIndex = A.CheckDiagIndex;
+        B.Label = A.Label;
+        B.InputLine = L;
+        B.Marker = Marker;
+        B.Marker.Lead = '~';
+        B.InputStartCol = 1;
+        if (L != E) {
+          B.InputEndCol = UINT_MAX;
+          B.Marker.Note = "";
+        } else
+          B.InputEndCol = DiagItr->InputEndCol;
+        B.FoundAndExpectedMatch = A.FoundAndExpectedMatch;
+        Annotations.push_back(B);
+      }
+    }
+  }
+}
+
+static void DumpAnnotatedInput(raw_ostream &OS, const FileCheckRequest &Req,
+                               StringRef InputFileText,
+                               std::vector<InputAnnotation> &Annotations,
+                               unsigned LabelWidth) {
+  OS << "Full input was:\n<<<<<<\n";
+
+  // Sort annotations.
+  //
+  // First, sort in the order of input lines to make it easier to find relevant
+  // annotations while iterating input lines in the implementation below.
+  // FileCheck diagnostics are not always reported and recorded in the order of
+  // input lines due to, for example, CHECK-DAG and CHECK-NOT.
+  //
+  // Second, for annotations for the same input line, sort in the order of the
+  // FileCheck directive's line in the check file (where there's at most one
+  // directive per line) and then by the index of the match result for that
+  // directive.  The rationale of this choice is that, for any input line, this
+  // sort establishes a total order of annotations that, with respect to match
+  // results, is consistent across multiple lines, thus making match results
+  // easier to track from one line to the next when they span multiple lines.
+  std::sort(Annotations.begin(), Annotations.end(),
+            [](const InputAnnotation &A, const InputAnnotation &B) {
+              if (A.InputLine != B.InputLine)
+                return A.InputLine < B.InputLine;
+              if (A.CheckLine != B.CheckLine)
+                return A.CheckLine < B.CheckLine;
+              // FIXME: Sometimes CHECK-LABEL reports its match twice with
+              // other diagnostics in between, and then diag index incrementing
+              // fails to work properly, and then this assert fails.  We should
+              // suppress one of those diagnostics or do a better job of
+              // computing this index.  For now, we just produce a redundant
+              // CHECK-LABEL annotation.
+              // assert(A.CheckDiagIndex != B.CheckDiagIndex &&
+              //        "expected diagnostic indices to be unique within a "
+              //        " check line");
+              return A.CheckDiagIndex < B.CheckDiagIndex;
+            });
+
+  // Compute the width of the label column.
+  const unsigned char *InputFilePtr = InputFileText.bytes_begin(),
+                      *InputFileEnd = InputFileText.bytes_end();
+  unsigned LineCount = InputFileText.count('\n');
+  if (InputFileEnd[-1] != '\n')
+    ++LineCount;
+  unsigned LineNoWidth = std::log10(LineCount) + 1;
+  // +3 below adds spaces (1) to the left of the (right-aligned) line numbers
+  // on input lines and (2) to the right of the (left-aligned) labels on
+  // annotation lines so that input lines and annotation lines are more
+  // visually distinct.  For example, the spaces on the annotation lines ensure
+  // that input line numbers and check directive line numbers never align
+  // horizontally.  Those line numbers might not even be for the same file.
+  // One space would be enough to achieve that, but more makes it even easier
+  // to see.
+  LabelWidth = std::max(LabelWidth, LineNoWidth) + 3;
+
+  // Print annotated input lines.
+  auto AnnotationItr = Annotations.begin(), AnnotationEnd = Annotations.end();
+  for (unsigned Line = 1;
+       InputFilePtr != InputFileEnd || AnnotationItr != AnnotationEnd;
+       ++Line) {
+    const unsigned char *InputFileLine = InputFilePtr;
+
+    // Print right-aligned line number.
+    WithColor(OS, raw_ostream::BLACK, true)
+        << format_decimal(Line, LabelWidth) << ": ";
+
+    // For the case where -v and colors are enabled, find the annotations for
+    // good matches for expected patterns in order to highlight everything
+    // else in the line.  There are no such annotations if -v is disabled.
+    std::vector<InputAnnotation> FoundAndExpectedMatches;
+    if (Req.Verbose && WithColor(OS).colorsEnabled()) {
+      for (auto I = AnnotationItr; I != AnnotationEnd && I->InputLine == Line;
+           ++I) {
+        if (I->FoundAndExpectedMatch)
+          FoundAndExpectedMatches.push_back(*I);
+      }
+    }
+
+    // Print numbered line with highlighting where there are no matches for
+    // expected patterns.
+    bool Newline = false;
+    {
+      WithColor COS(OS);
+      bool InMatch = false;
+      if (Req.Verbose)
+        COS.changeColor(raw_ostream::CYAN, true, true);
+      for (unsigned Col = 1; InputFilePtr != InputFileEnd && !Newline; ++Col) {
+        bool WasInMatch = InMatch;
+        InMatch = false;
+        for (auto M : FoundAndExpectedMatches) {
+          if (M.InputStartCol <= Col && Col < M.InputEndCol) {
+            InMatch = true;
+            break;
+          }
+        }
+        if (!WasInMatch && InMatch)
+          COS.resetColor();
+        else if (WasInMatch && !InMatch)
+          COS.changeColor(raw_ostream::CYAN, true, true);
+        if (*InputFilePtr == '\n')
+          Newline = true;
+        else
+          COS << *InputFilePtr;
+        ++InputFilePtr;
+      }
+    }
+    OS << '\n';
+    unsigned InputLineWidth = InputFilePtr - InputFileLine - Newline;
+
+    // Print any annotations.
+    while (AnnotationItr != AnnotationEnd &&
+           AnnotationItr->InputLine == Line) {
+      WithColor COS(OS, AnnotationItr->Marker.Color, true);
+      // The two spaces below are where the ": " appears on input lines.
+      COS << left_justify(AnnotationItr->Label, LabelWidth) << "  ";
+      unsigned Col;
+      for (Col = 1; Col < AnnotationItr->InputStartCol; ++Col)
+        COS << ' ';
+      COS << AnnotationItr->Marker.Lead;
+      // If InputEndCol=UINT_MAX, stop at InputLineWidth.
+      for (++Col; Col < AnnotationItr->InputEndCol && Col <= InputLineWidth;
+           ++Col)
+        COS << '~';
+      const std::string &Note = AnnotationItr->Marker.Note;
+      if (!Note.empty()) {
+        // Put the note at the end of the input line.  If we were to instead
+        // put the note right after the marker, subsequent annotations for the
+        // same input line might appear to mark this note instead of the input
+        // line.
+        for (; Col <= InputLineWidth; ++Col)
+          COS << ' ';
+        COS << ' ' << Note;
+      }
+      COS << '\n';
+      ++AnnotationItr;
+    }
+  }
+
+  OS << ">>>>>>\n";
+}
+
+int main(int argc, char **argv) {
+  // Enable use of ANSI color codes because FileCheck is using them to
+  // highlight text.
+  llvm::sys::Process::UseANSIEscapeCodes(true);
+
+  InitLLVM X(argc, argv);
+  cl::ParseCommandLineOptions(argc, argv, /*Overview*/ "", /*Errs*/ nullptr,
+                              "FILECHECK_OPTS");
+  if (DumpInput == DumpInputHelp) {
+    DumpInputAnnotationHelp(outs());
+    return 0;
+  }
+  if (CheckFilename.empty()) {
+    errs() << "<check-file> not specified\n";
+    return 2;
+  }
+
+  FileCheckRequest Req;
+  for (auto Prefix : CheckPrefixes)
+    Req.CheckPrefixes.push_back(Prefix);
+
+  for (auto CheckNot : ImplicitCheckNot)
+    Req.ImplicitCheckNot.push_back(CheckNot);
+
+  bool GlobalDefineError = false;
+  for (auto G : GlobalDefines) {
+    size_t EqIdx = G.find('=');
+    if (EqIdx == std::string::npos) {
+      errs() << "Missing equal sign in command-line definition '-D" << G
+             << "'\n";
+      GlobalDefineError = true;
+      continue;
+    }
+    if (EqIdx == 0) {
+      errs() << "Missing variable name in command-line definition '-D" << G
+             << "'\n";
+      GlobalDefineError = true;
+      continue;
+    }
+    Req.GlobalDefines.push_back(G);
+  }
+  if (GlobalDefineError)
+    return 2;
+
+  Req.AllowEmptyInput = AllowEmptyInput;
+  Req.EnableVarScope = EnableVarScope;
+  Req.AllowDeprecatedDagOverlap = AllowDeprecatedDagOverlap;
+  Req.Verbose = Verbose;
+  Req.VerboseVerbose = VerboseVerbose;
+  Req.NoCanonicalizeWhiteSpace = NoCanonicalizeWhiteSpace;
+  Req.MatchFullLines = MatchFullLines;
+
+  if (VerboseVerbose)
+    Req.Verbose = true;
+
+  FileCheck FC(Req);
+  if (!FC.ValidateCheckPrefixes()) {
+    errs() << "Supplied check-prefix is invalid! Prefixes must be unique and "
+              "start with a letter and contain only alphanumeric characters, "
+              "hyphens and underscores\n";
+    return 2;
+  }
+
+  Regex PrefixRE = FC.buildCheckPrefixRegex();
+  std::string REError;
+  if (!PrefixRE.isValid(REError)) {
+    errs() << "Unable to combine check-prefix strings into a prefix regular "
+              "expression! This is likely a bug in FileCheck's verification of "
+              "the check-prefix strings. Regular expression parsing failed "
+              "with the following error: "
+           << REError << "\n";
+    return 2;
+  }
+
+  SourceMgr SM;
+
+  // Read the expected strings from the check file.
+  ErrorOr<std::unique_ptr<MemoryBuffer>> CheckFileOrErr =
+      MemoryBuffer::getFileOrSTDIN(CheckFilename);
+  if (std::error_code EC = CheckFileOrErr.getError()) {
+    errs() << "Could not open check file '" << CheckFilename
+           << "': " << EC.message() << '\n';
+    return 2;
+  }
+  MemoryBuffer &CheckFile = *CheckFileOrErr.get();
+
+  SmallString<4096> CheckFileBuffer;
+  StringRef CheckFileText = FC.CanonicalizeFile(CheckFile, CheckFileBuffer);
+
+  SM.AddNewSourceBuffer(MemoryBuffer::getMemBuffer(
+                            CheckFileText, CheckFile.getBufferIdentifier()),
+                        SMLoc());
+
+  std::vector<FileCheckString> CheckStrings;
+  if (FC.ReadCheckFile(SM, CheckFileText, PrefixRE, CheckStrings))
+    return 2;
+
+  // Open the file to check and add it to SourceMgr.
+  ErrorOr<std::unique_ptr<MemoryBuffer>> InputFileOrErr =
+      MemoryBuffer::getFileOrSTDIN(InputFilename);
+  if (std::error_code EC = InputFileOrErr.getError()) {
+    errs() << "Could not open input file '" << InputFilename
+           << "': " << EC.message() << '\n';
+    return 2;
+  }
+  MemoryBuffer &InputFile = *InputFileOrErr.get();
+
+  if (InputFile.getBufferSize() == 0 && !AllowEmptyInput) {
+    errs() << "FileCheck error: '" << InputFilename << "' is empty.\n";
+    DumpCommandLine(argc, argv);
+    return 2;
+  }
+
+  SmallString<4096> InputFileBuffer;
+  StringRef InputFileText = FC.CanonicalizeFile(InputFile, InputFileBuffer);
+
+  SM.AddNewSourceBuffer(MemoryBuffer::getMemBuffer(
+                            InputFileText, InputFile.getBufferIdentifier()),
+                        SMLoc());
+
+  if (DumpInput == DumpInputDefault)
+    DumpInput = DumpInputOnFailure ? DumpInputFail : DumpInputNever;
+
+  std::vector<FileCheckDiag> Diags;
+  int ExitCode = FC.CheckInput(SM, InputFileText, CheckStrings,
+                               DumpInput == DumpInputNever ? nullptr : &Diags)
+                     ? EXIT_SUCCESS
+                     : 1;
+  if (DumpInput == DumpInputAlways ||
+      (ExitCode == 1 && DumpInput == DumpInputFail)) {
+    errs() << "\n"
+           << "Input file: "
+           << (InputFilename == "-" ? "<stdin>" : InputFilename.getValue())
+           << "\n"
+           << "Check file: " << CheckFilename << "\n"
+           << "\n"
+           << "-dump-input=help describes the format of the following dump.\n"
+           << "\n";
+    std::vector<InputAnnotation> Annotations;
+    unsigned LabelWidth;
+    BuildInputAnnotations(Diags, Annotations, LabelWidth);
+    DumpAnnotatedInput(errs(), Req, InputFileText, Annotations, LabelWidth);
+  }
+
+  return ExitCode;
+}