Bug Summary

File:tools/clang/lib/Format/UnwrappedLineFormatter.cpp
Warning:line 1089, column 11
Access to field 'NewlinesBefore' results in a dereference of a null pointer (loaded from field 'First')

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name UnwrappedLineFormatter.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-eagerly-assume -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-7/lib/clang/7.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/clang/lib/Format -I /build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format -I /build/llvm-toolchain-snapshot-7~svn329677/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/include -I /build/llvm-toolchain-snapshot-7~svn329677/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0/backward -internal-isystem /usr/include/clang/7.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-7/lib/clang/7.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/clang/lib/Format -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-04-11-031539-24776-1 -x c++ /build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp
1//===--- UnwrappedLineFormatter.cpp - Format C++ code ---------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "UnwrappedLineFormatter.h"
11#include "WhitespaceManager.h"
12#include "llvm/Support/Debug.h"
13#include <queue>
14
15#define DEBUG_TYPE"format-formatter" "format-formatter"
16
17namespace clang {
18namespace format {
19
20namespace {
21
22bool startsExternCBlock(const AnnotatedLine &Line) {
23 const FormatToken *Next = Line.First->getNextNonComment();
24 const FormatToken *NextNext = Next ? Next->getNextNonComment() : nullptr;
25 return Line.startsWith(tok::kw_extern) && Next && Next->isStringLiteral() &&
26 NextNext && NextNext->is(tok::l_brace);
27}
28
29/// \brief Tracks the indent level of \c AnnotatedLines across levels.
30///
31/// \c nextLine must be called for each \c AnnotatedLine, after which \c
32/// getIndent() will return the indent for the last line \c nextLine was called
33/// with.
34/// If the line is not formatted (and thus the indent does not change), calling
35/// \c adjustToUnmodifiedLine after the call to \c nextLine will cause
36/// subsequent lines on the same level to be indented at the same level as the
37/// given line.
38class LevelIndentTracker {
39public:
40 LevelIndentTracker(const FormatStyle &Style,
41 const AdditionalKeywords &Keywords, unsigned StartLevel,
42 int AdditionalIndent)
43 : Style(Style), Keywords(Keywords), AdditionalIndent(AdditionalIndent) {
44 for (unsigned i = 0; i != StartLevel; ++i)
45 IndentForLevel.push_back(Style.IndentWidth * i + AdditionalIndent);
46 }
47
48 /// \brief Returns the indent for the current line.
49 unsigned getIndent() const { return Indent; }
50
51 /// \brief Update the indent state given that \p Line is going to be formatted
52 /// next.
53 void nextLine(const AnnotatedLine &Line) {
54 Offset = getIndentOffset(*Line.First);
55 // Update the indent level cache size so that we can rely on it
56 // having the right size in adjustToUnmodifiedline.
57 while (IndentForLevel.size() <= Line.Level)
58 IndentForLevel.push_back(-1);
59 if (Line.InPPDirective) {
60 Indent = Line.Level * Style.IndentWidth + AdditionalIndent;
61 } else {
62 IndentForLevel.resize(Line.Level + 1);
63 Indent = getIndent(IndentForLevel, Line.Level);
64 }
65 if (static_cast<int>(Indent) + Offset >= 0)
66 Indent += Offset;
67 }
68
69 /// \brief Update the indent state given that \p Line indent should be
70 /// skipped.
71 void skipLine(const AnnotatedLine &Line) {
72 while (IndentForLevel.size() <= Line.Level)
73 IndentForLevel.push_back(Indent);
74 }
75
76 /// \brief Update the level indent to adapt to the given \p Line.
77 ///
78 /// When a line is not formatted, we move the subsequent lines on the same
79 /// level to the same indent.
80 /// Note that \c nextLine must have been called before this method.
81 void adjustToUnmodifiedLine(const AnnotatedLine &Line) {
82 unsigned LevelIndent = Line.First->OriginalColumn;
83 if (static_cast<int>(LevelIndent) - Offset >= 0)
84 LevelIndent -= Offset;
85 if ((!Line.First->is(tok::comment) || IndentForLevel[Line.Level] == -1) &&
86 !Line.InPPDirective)
87 IndentForLevel[Line.Level] = LevelIndent;
88 }
89
90private:
91 /// \brief Get the offset of the line relatively to the level.
92 ///
93 /// For example, 'public:' labels in classes are offset by 1 or 2
94 /// characters to the left from their level.
95 int getIndentOffset(const FormatToken &RootToken) {
96 if (Style.Language == FormatStyle::LK_Java ||
97 Style.Language == FormatStyle::LK_JavaScript)
98 return 0;
99 if (RootToken.isAccessSpecifier(false) ||
100 RootToken.isObjCAccessSpecifier() ||
101 (RootToken.isOneOf(Keywords.kw_signals, Keywords.kw_qsignals) &&
102 RootToken.Next && RootToken.Next->is(tok::colon)))
103 return Style.AccessModifierOffset;
104 return 0;
105 }
106
107 /// \brief Get the indent of \p Level from \p IndentForLevel.
108 ///
109 /// \p IndentForLevel must contain the indent for the level \c l
110 /// at \p IndentForLevel[l], or a value < 0 if the indent for
111 /// that level is unknown.
112 unsigned getIndent(ArrayRef<int> IndentForLevel, unsigned Level) {
113 if (IndentForLevel[Level] != -1)
114 return IndentForLevel[Level];
115 if (Level == 0)
116 return 0;
117 return getIndent(IndentForLevel, Level - 1) + Style.IndentWidth;
118 }
119
120 const FormatStyle &Style;
121 const AdditionalKeywords &Keywords;
122 const unsigned AdditionalIndent;
123
124 /// \brief The indent in characters for each level.
125 std::vector<int> IndentForLevel;
126
127 /// \brief Offset of the current line relative to the indent level.
128 ///
129 /// For example, the 'public' keywords is often indented with a negative
130 /// offset.
131 int Offset = 0;
132
133 /// \brief The current line's indent.
134 unsigned Indent = 0;
135};
136
137bool isNamespaceDeclaration(const AnnotatedLine *Line) {
138 const FormatToken *NamespaceTok = Line->First;
139 return NamespaceTok && NamespaceTok->getNamespaceToken();
140}
141
142bool isEndOfNamespace(const AnnotatedLine *Line,
143 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
144 if (!Line->startsWith(tok::r_brace))
145 return false;
146 size_t StartLineIndex = Line->MatchingOpeningBlockLineIndex;
147 if (StartLineIndex == UnwrappedLine::kInvalidIndex)
148 return false;
149 assert(StartLineIndex < AnnotatedLines.size())(static_cast <bool> (StartLineIndex < AnnotatedLines
.size()) ? void (0) : __assert_fail ("StartLineIndex < AnnotatedLines.size()"
, "/build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp"
, 149, __extension__ __PRETTY_FUNCTION__));
150 return isNamespaceDeclaration(AnnotatedLines[StartLineIndex]);
151}
152
153class LineJoiner {
154public:
155 LineJoiner(const FormatStyle &Style, const AdditionalKeywords &Keywords,
156 const SmallVectorImpl<AnnotatedLine *> &Lines)
157 : Style(Style), Keywords(Keywords), End(Lines.end()), Next(Lines.begin()),
158 AnnotatedLines(Lines) {}
159
160 /// \brief Returns the next line, merging multiple lines into one if possible.
161 const AnnotatedLine *getNextMergedLine(bool DryRun,
162 LevelIndentTracker &IndentTracker) {
163 if (Next == End)
164 return nullptr;
165 const AnnotatedLine *Current = *Next;
166 IndentTracker.nextLine(*Current);
167 unsigned MergedLines = tryFitMultipleLinesInOne(IndentTracker, Next, End);
168 if (MergedLines > 0 && Style.ColumnLimit == 0)
169 // Disallow line merging if there is a break at the start of one of the
170 // input lines.
171 for (unsigned i = 0; i < MergedLines; ++i)
172 if (Next[i + 1]->First->NewlinesBefore > 0)
173 MergedLines = 0;
174 if (!DryRun)
175 for (unsigned i = 0; i < MergedLines; ++i)
176 join(*Next[0], *Next[i + 1]);
177 Next = Next + MergedLines + 1;
178 return Current;
179 }
180
181private:
182 /// \brief Calculates how many lines can be merged into 1 starting at \p I.
183 unsigned
184 tryFitMultipleLinesInOne(LevelIndentTracker &IndentTracker,
185 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
186 SmallVectorImpl<AnnotatedLine *>::const_iterator E) {
187 const unsigned Indent = IndentTracker.getIndent();
188
189 // Can't join the last line with anything.
190 if (I + 1 == E)
191 return 0;
192 // We can never merge stuff if there are trailing line comments.
193 const AnnotatedLine *TheLine = *I;
194 if (TheLine->Last->is(TT_LineComment))
195 return 0;
196 if (I[1]->Type == LT_Invalid || I[1]->First->MustBreakBefore)
197 return 0;
198 if (TheLine->InPPDirective &&
199 (!I[1]->InPPDirective || I[1]->First->HasUnescapedNewline))
200 return 0;
201
202 if (Style.ColumnLimit > 0 && Indent > Style.ColumnLimit)
203 return 0;
204
205 unsigned Limit =
206 Style.ColumnLimit == 0 ? UINT_MAX(2147483647 *2U +1U) : Style.ColumnLimit - Indent;
207 // If we already exceed the column limit, we set 'Limit' to 0. The different
208 // tryMerge..() functions can then decide whether to still do merging.
209 Limit = TheLine->Last->TotalLength > Limit
210 ? 0
211 : Limit - TheLine->Last->TotalLength;
212
213 if (TheLine->Last->is(TT_FunctionLBrace) &&
214 TheLine->First == TheLine->Last &&
215 !Style.BraceWrapping.SplitEmptyFunction &&
216 I[1]->First->is(tok::r_brace))
217 return tryMergeSimpleBlock(I, E, Limit);
218
219 // Handle empty record blocks where the brace has already been wrapped
220 if (TheLine->Last->is(tok::l_brace) && TheLine->First == TheLine->Last &&
221 I != AnnotatedLines.begin()) {
222 bool EmptyBlock = I[1]->First->is(tok::r_brace);
223
224 const FormatToken *Tok = I[-1]->First;
225 if (Tok && Tok->is(tok::comment))
226 Tok = Tok->getNextNonComment();
227
228 if (Tok && Tok->getNamespaceToken())
229 return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock
230 ? tryMergeSimpleBlock(I, E, Limit)
231 : 0;
232
233 if (Tok && Tok->is(tok::kw_typedef))
234 Tok = Tok->getNextNonComment();
235 if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
236 tok::kw_extern, Keywords.kw_interface))
237 return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
238 ? tryMergeSimpleBlock(I, E, Limit)
239 : 0;
240 }
241
242 // FIXME: TheLine->Level != 0 might or might not be the right check to do.
243 // If necessary, change to something smarter.
244 bool MergeShortFunctions =
245 Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_All ||
246 (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
247 I[1]->First->is(tok::r_brace)) ||
248 (Style.AllowShortFunctionsOnASingleLine & FormatStyle::SFS_InlineOnly &&
249 TheLine->Level != 0);
250
251 if (Style.CompactNamespaces) {
252 if (isNamespaceDeclaration(TheLine)) {
253 int i = 0;
254 unsigned closingLine = TheLine->MatchingOpeningBlockLineIndex - 1;
255 for (; I + 1 + i != E && isNamespaceDeclaration(I[i + 1]) &&
256 closingLine == I[i + 1]->MatchingOpeningBlockLineIndex &&
257 I[i + 1]->Last->TotalLength < Limit;
258 i++, closingLine--) {
259 // No extra indent for compacted namespaces
260 IndentTracker.skipLine(*I[i + 1]);
261
262 Limit -= I[i + 1]->Last->TotalLength;
263 }
264 return i;
265 }
266
267 if (isEndOfNamespace(TheLine, AnnotatedLines)) {
268 int i = 0;
269 unsigned openingLine = TheLine->MatchingOpeningBlockLineIndex - 1;
270 for (; I + 1 + i != E && isEndOfNamespace(I[i + 1], AnnotatedLines) &&
271 openingLine == I[i + 1]->MatchingOpeningBlockLineIndex;
272 i++, openingLine--) {
273 // No space between consecutive braces
274 I[i + 1]->First->SpacesRequiredBefore = !I[i]->Last->is(tok::r_brace);
275
276 // Indent like the outer-most namespace
277 IndentTracker.nextLine(*I[i + 1]);
278 }
279 return i;
280 }
281 }
282
283 // Try to merge a function block with left brace unwrapped
284 if (TheLine->Last->is(TT_FunctionLBrace) &&
285 TheLine->First != TheLine->Last) {
286 return MergeShortFunctions ? tryMergeSimpleBlock(I, E, Limit) : 0;
287 }
288 // Try to merge a control statement block with left brace unwrapped
289 if (TheLine->Last->is(tok::l_brace) && TheLine->First != TheLine->Last &&
290 TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for)) {
291 return Style.AllowShortBlocksOnASingleLine
292 ? tryMergeSimpleBlock(I, E, Limit)
293 : 0;
294 }
295 // Try to merge a control statement block with left brace wrapped
296 if (I[1]->First->is(tok::l_brace) &&
297 TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for)) {
298 return Style.BraceWrapping.AfterControlStatement
299 ? tryMergeSimpleBlock(I, E, Limit)
300 : 0;
301 }
302 // Try to merge either empty or one-line block if is precedeed by control
303 // statement token
304 if (TheLine->First->is(tok::l_brace) && TheLine->First == TheLine->Last &&
305 I != AnnotatedLines.begin() &&
306 I[-1]->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for)) {
307 unsigned MergedLines = 0;
308 if (Style.AllowShortBlocksOnASingleLine) {
309 MergedLines = tryMergeSimpleBlock(I - 1, E, Limit);
310 // If we managed to merge the block, discard the first merged line
311 // since we are merging starting from I.
312 if (MergedLines > 0)
313 --MergedLines;
314 }
315 return MergedLines;
316 }
317 // Don't merge block with left brace wrapped after ObjC special blocks
318 if (TheLine->First->is(tok::l_brace) && I != AnnotatedLines.begin() &&
319 I[-1]->First->is(tok::at) && I[-1]->First->Next) {
320 tok::ObjCKeywordKind kwId = I[-1]->First->Next->Tok.getObjCKeywordID();
321 if (kwId == clang::tok::objc_autoreleasepool ||
322 kwId == clang::tok::objc_synchronized)
323 return 0;
324 }
325 // Try to merge a block with left brace wrapped that wasn't yet covered
326 if (TheLine->Last->is(tok::l_brace)) {
327 return !Style.BraceWrapping.AfterFunction ||
328 (I[1]->First->is(tok::r_brace) &&
329 !Style.BraceWrapping.SplitEmptyRecord)
330 ? tryMergeSimpleBlock(I, E, Limit)
331 : 0;
332 }
333 // Try to merge a function block with left brace wrapped
334 if (I[1]->First->is(TT_FunctionLBrace) &&
335 Style.BraceWrapping.AfterFunction) {
336 if (I[1]->Last->is(TT_LineComment))
337 return 0;
338
339 // Check for Limit <= 2 to account for the " {".
340 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(TheLine)))
341 return 0;
342 Limit -= 2;
343
344 unsigned MergedLines = 0;
345 if (MergeShortFunctions ||
346 (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
347 I[1]->First == I[1]->Last && I + 2 != E &&
348 I[2]->First->is(tok::r_brace))) {
349 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
350 // If we managed to merge the block, count the function header, which is
351 // on a separate line.
352 if (MergedLines > 0)
353 ++MergedLines;
354 }
355 return MergedLines;
356 }
357 if (TheLine->First->is(tok::kw_if)) {
358 return Style.AllowShortIfStatementsOnASingleLine
359 ? tryMergeSimpleControlStatement(I, E, Limit)
360 : 0;
361 }
362 if (TheLine->First->isOneOf(tok::kw_for, tok::kw_while)) {
363 return Style.AllowShortLoopsOnASingleLine
364 ? tryMergeSimpleControlStatement(I, E, Limit)
365 : 0;
366 }
367 if (TheLine->First->isOneOf(tok::kw_case, tok::kw_default)) {
368 return Style.AllowShortCaseLabelsOnASingleLine
369 ? tryMergeShortCaseLabels(I, E, Limit)
370 : 0;
371 }
372 if (TheLine->InPPDirective &&
373 (TheLine->First->HasUnescapedNewline || TheLine->First->IsFirst)) {
374 return tryMergeSimplePPDirective(I, E, Limit);
375 }
376 return 0;
377 }
378
379 unsigned
380 tryMergeSimplePPDirective(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
381 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
382 unsigned Limit) {
383 if (Limit == 0)
384 return 0;
385 if (I + 2 != E && I[2]->InPPDirective && !I[2]->First->HasUnescapedNewline)
386 return 0;
387 if (1 + I[1]->Last->TotalLength > Limit)
388 return 0;
389 return 1;
390 }
391
392 unsigned tryMergeSimpleControlStatement(
393 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
394 SmallVectorImpl<AnnotatedLine *>::const_iterator E, unsigned Limit) {
395 if (Limit == 0)
396 return 0;
397 if (Style.BraceWrapping.AfterControlStatement &&
398 (I[1]->First->is(tok::l_brace) && !Style.AllowShortBlocksOnASingleLine))
399 return 0;
400 if (I[1]->InPPDirective != (*I)->InPPDirective ||
401 (I[1]->InPPDirective && I[1]->First->HasUnescapedNewline))
402 return 0;
403 Limit = limitConsideringMacros(I + 1, E, Limit);
404 AnnotatedLine &Line = **I;
405 if (Line.Last->isNot(tok::r_paren))
406 return 0;
407 if (1 + I[1]->Last->TotalLength > Limit)
408 return 0;
409 if (I[1]->First->isOneOf(tok::semi, tok::kw_if, tok::kw_for, tok::kw_while,
410 TT_LineComment))
411 return 0;
412 // Only inline simple if's (no nested if or else).
413 if (I + 2 != E && Line.startsWith(tok::kw_if) &&
414 I[2]->First->is(tok::kw_else))
415 return 0;
416 return 1;
417 }
418
419 unsigned
420 tryMergeShortCaseLabels(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
421 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
422 unsigned Limit) {
423 if (Limit == 0 || I + 1 == E ||
424 I[1]->First->isOneOf(tok::kw_case, tok::kw_default))
425 return 0;
426 unsigned NumStmts = 0;
427 unsigned Length = 0;
428 bool EndsWithComment = false;
429 bool InPPDirective = I[0]->InPPDirective;
430 const unsigned Level = I[0]->Level;
431 for (; NumStmts < 3; ++NumStmts) {
432 if (I + 1 + NumStmts == E)
433 break;
434 const AnnotatedLine *Line = I[1 + NumStmts];
435 if (Line->InPPDirective != InPPDirective)
436 break;
437 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
438 break;
439 if (Line->First->isOneOf(tok::kw_if, tok::kw_for, tok::kw_switch,
440 tok::kw_while) ||
441 EndsWithComment)
442 return 0;
443 if (Line->First->is(tok::comment)) {
444 if (Level != Line->Level)
445 return 0;
446 SmallVectorImpl<AnnotatedLine *>::const_iterator J = I + 2 + NumStmts;
447 for (; J != E; ++J) {
448 Line = *J;
449 if (Line->InPPDirective != InPPDirective)
450 break;
451 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
452 break;
453 if (Line->First->isNot(tok::comment) || Level != Line->Level)
454 return 0;
455 }
456 break;
457 }
458 if (Line->Last->is(tok::comment))
459 EndsWithComment = true;
460 Length += I[1 + NumStmts]->Last->TotalLength + 1; // 1 for the space.
461 }
462 if (NumStmts == 0 || NumStmts == 3 || Length > Limit)
463 return 0;
464 return NumStmts;
465 }
466
467 unsigned
468 tryMergeSimpleBlock(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
469 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
470 unsigned Limit) {
471 AnnotatedLine &Line = **I;
472
473 // Don't merge ObjC @ keywords and methods.
474 // FIXME: If an option to allow short exception handling clauses on a single
475 // line is added, change this to not return for @try and friends.
476 if (Style.Language != FormatStyle::LK_Java &&
477 Line.First->isOneOf(tok::at, tok::minus, tok::plus))
478 return 0;
479
480 // Check that the current line allows merging. This depends on whether we
481 // are in a control flow statements as well as several style flags.
482 if (Line.First->isOneOf(tok::kw_else, tok::kw_case) ||
483 (Line.First->Next && Line.First->Next->is(tok::kw_else)))
484 return 0;
485 if (Line.First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_do, tok::kw_try,
486 tok::kw___try, tok::kw_catch, tok::kw___finally,
487 tok::kw_for, tok::r_brace, Keywords.kw___except)) {
488 if (!Style.AllowShortBlocksOnASingleLine)
489 return 0;
490 // Don't merge when we can't except the case when
491 // the control statement block is empty
492 if (!Style.AllowShortIfStatementsOnASingleLine &&
493 Line.startsWith(tok::kw_if) &&
494 !Style.BraceWrapping.AfterControlStatement &&
495 !I[1]->First->is(tok::r_brace))
496 return 0;
497 if (!Style.AllowShortIfStatementsOnASingleLine &&
498 Line.startsWith(tok::kw_if) &&
499 Style.BraceWrapping.AfterControlStatement && I + 2 != E &&
500 !I[2]->First->is(tok::r_brace))
501 return 0;
502 if (!Style.AllowShortLoopsOnASingleLine &&
503 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
504 !Style.BraceWrapping.AfterControlStatement &&
505 !I[1]->First->is(tok::r_brace))
506 return 0;
507 if (!Style.AllowShortLoopsOnASingleLine &&
508 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
509 Style.BraceWrapping.AfterControlStatement && I + 2 != E &&
510 !I[2]->First->is(tok::r_brace))
511 return 0;
512 // FIXME: Consider an option to allow short exception handling clauses on
513 // a single line.
514 // FIXME: This isn't covered by tests.
515 // FIXME: For catch, __except, __finally the first token on the line
516 // is '}', so this isn't correct here.
517 if (Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch,
518 Keywords.kw___except, tok::kw___finally))
519 return 0;
520 }
521
522 if (Line.Last->is(tok::l_brace)) {
523 FormatToken *Tok = I[1]->First;
524 if (Tok->is(tok::r_brace) && !Tok->MustBreakBefore &&
525 (Tok->getNextNonComment() == nullptr ||
526 Tok->getNextNonComment()->is(tok::semi))) {
527 // We merge empty blocks even if the line exceeds the column limit.
528 Tok->SpacesRequiredBefore = 0;
529 Tok->CanBreakBefore = true;
530 return 1;
531 } else if (Limit != 0 && !Line.startsWith(tok::kw_namespace) &&
532 !startsExternCBlock(Line)) {
533 // We don't merge short records.
534 FormatToken *RecordTok = Line.First;
535 // Skip record modifiers.
536 while (RecordTok->Next &&
537 RecordTok->isOneOf(tok::kw_typedef, tok::kw_export,
538 Keywords.kw_declare, Keywords.kw_abstract,
539 tok::kw_default))
540 RecordTok = RecordTok->Next;
541 if (RecordTok &&
542 RecordTok->isOneOf(tok::kw_class, tok::kw_union, tok::kw_struct,
543 Keywords.kw_interface))
544 return 0;
545
546 // Check that we still have three lines and they fit into the limit.
547 if (I + 2 == E || I[2]->Type == LT_Invalid)
548 return 0;
549 Limit = limitConsideringMacros(I + 2, E, Limit);
550
551 if (!nextTwoLinesFitInto(I, Limit))
552 return 0;
553
554 // Second, check that the next line does not contain any braces - if it
555 // does, readability declines when putting it into a single line.
556 if (I[1]->Last->is(TT_LineComment))
557 return 0;
558 do {
559 if (Tok->is(tok::l_brace) && Tok->BlockKind != BK_BracedInit)
560 return 0;
561 Tok = Tok->Next;
562 } while (Tok);
563
564 // Last, check that the third line starts with a closing brace.
565 Tok = I[2]->First;
566 if (Tok->isNot(tok::r_brace))
567 return 0;
568
569 // Don't merge "if (a) { .. } else {".
570 if (Tok->Next && Tok->Next->is(tok::kw_else))
571 return 0;
572
573 return 2;
574 }
575 } else if (I[1]->First->is(tok::l_brace)) {
576 if (I[1]->Last->is(TT_LineComment))
577 return 0;
578
579 // Check for Limit <= 2 to account for the " {".
580 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(*I)))
581 return 0;
582 Limit -= 2;
583 unsigned MergedLines = 0;
584 if (Style.AllowShortBlocksOnASingleLine ||
585 (I[1]->First == I[1]->Last && I + 2 != E &&
586 I[2]->First->is(tok::r_brace))) {
587 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
588 // If we managed to merge the block, count the statement header, which
589 // is on a separate line.
590 if (MergedLines > 0)
591 ++MergedLines;
592 }
593 return MergedLines;
594 }
595 return 0;
596 }
597
598 /// Returns the modified column limit for \p I if it is inside a macro and
599 /// needs a trailing '\'.
600 unsigned
601 limitConsideringMacros(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
602 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
603 unsigned Limit) {
604 if (I[0]->InPPDirective && I + 1 != E &&
605 !I[1]->First->HasUnescapedNewline && !I[1]->First->is(tok::eof)) {
606 return Limit < 2 ? 0 : Limit - 2;
607 }
608 return Limit;
609 }
610
611 bool nextTwoLinesFitInto(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
612 unsigned Limit) {
613 if (I[1]->First->MustBreakBefore || I[2]->First->MustBreakBefore)
614 return false;
615 return 1 + I[1]->Last->TotalLength + 1 + I[2]->Last->TotalLength <= Limit;
616 }
617
618 bool containsMustBreak(const AnnotatedLine *Line) {
619 for (const FormatToken *Tok = Line->First; Tok; Tok = Tok->Next) {
620 if (Tok->MustBreakBefore)
621 return true;
622 }
623 return false;
624 }
625
626 void join(AnnotatedLine &A, const AnnotatedLine &B) {
627 assert(!A.Last->Next)(static_cast <bool> (!A.Last->Next) ? void (0) : __assert_fail
("!A.Last->Next", "/build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp"
, 627, __extension__ __PRETTY_FUNCTION__));
628 assert(!B.First->Previous)(static_cast <bool> (!B.First->Previous) ? void (0) :
__assert_fail ("!B.First->Previous", "/build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp"
, 628, __extension__ __PRETTY_FUNCTION__));
629 if (B.Affected)
630 A.Affected = true;
631 A.Last->Next = B.First;
632 B.First->Previous = A.Last;
633 B.First->CanBreakBefore = true;
634 unsigned LengthA = A.Last->TotalLength + B.First->SpacesRequiredBefore;
635 for (FormatToken *Tok = B.First; Tok; Tok = Tok->Next) {
636 Tok->TotalLength += LengthA;
637 A.Last = Tok;
638 }
639 }
640
641 const FormatStyle &Style;
642 const AdditionalKeywords &Keywords;
643 const SmallVectorImpl<AnnotatedLine *>::const_iterator End;
644
645 SmallVectorImpl<AnnotatedLine *>::const_iterator Next;
646 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines;
647};
648
649static void markFinalized(FormatToken *Tok) {
650 for (; Tok; Tok = Tok->Next) {
651 Tok->Finalized = true;
652 for (AnnotatedLine *Child : Tok->Children)
653 markFinalized(Child->First);
654 }
655}
656
657#ifndef NDEBUG
658static void printLineState(const LineState &State) {
659 llvm::dbgs() << "State: ";
660 for (const ParenState &P : State.Stack) {
661 llvm::dbgs() << P.Indent << "|" << P.LastSpace << "|" << P.NestedBlockIndent
662 << " ";
663 }
664 llvm::dbgs() << State.NextToken->TokenText << "\n";
665}
666#endif
667
668/// \brief Base class for classes that format one \c AnnotatedLine.
669class LineFormatter {
670public:
671 LineFormatter(ContinuationIndenter *Indenter, WhitespaceManager *Whitespaces,
672 const FormatStyle &Style,
673 UnwrappedLineFormatter *BlockFormatter)
674 : Indenter(Indenter), Whitespaces(Whitespaces), Style(Style),
675 BlockFormatter(BlockFormatter) {}
676 virtual ~LineFormatter() {}
677
678 /// \brief Formats an \c AnnotatedLine and returns the penalty.
679 ///
680 /// If \p DryRun is \c false, directly applies the changes.
681 virtual unsigned formatLine(const AnnotatedLine &Line,
682 unsigned FirstIndent,
683 unsigned FirstStartColumn,
684 bool DryRun) = 0;
685
686protected:
687 /// \brief If the \p State's next token is an r_brace closing a nested block,
688 /// format the nested block before it.
689 ///
690 /// Returns \c true if all children could be placed successfully and adapts
691 /// \p Penalty as well as \p State. If \p DryRun is false, also directly
692 /// creates changes using \c Whitespaces.
693 ///
694 /// The crucial idea here is that children always get formatted upon
695 /// encountering the closing brace right after the nested block. Now, if we
696 /// are currently trying to keep the "}" on the same line (i.e. \p NewLine is
697 /// \c false), the entire block has to be kept on the same line (which is only
698 /// possible if it fits on the line, only contains a single statement, etc.
699 ///
700 /// If \p NewLine is true, we format the nested block on separate lines, i.e.
701 /// break after the "{", format all lines with correct indentation and the put
702 /// the closing "}" on yet another new line.
703 ///
704 /// This enables us to keep the simple structure of the
705 /// \c UnwrappedLineFormatter, where we only have two options for each token:
706 /// break or don't break.
707 bool formatChildren(LineState &State, bool NewLine, bool DryRun,
708 unsigned &Penalty) {
709 const FormatToken *LBrace = State.NextToken->getPreviousNonComment();
710 FormatToken &Previous = *State.NextToken->Previous;
711 if (!LBrace || LBrace->isNot(tok::l_brace) ||
3
←
Taking false branch
→
712 LBrace->BlockKind != BK_Block || Previous.Children.size() == 0)
1
Assuming the condition is false
→
2
←
Assuming the condition is false
→
713 // The previous token does not open a block. Nothing to do. We don't
714 // assert so that we can simply call this function for all tokens.
715 return true;
716
717 if (NewLine) {
4
←
Assuming 'NewLine' is not equal to 0
→
5
←
Taking true branch
→
718 int AdditionalIndent = State.Stack.back().Indent -
719 Previous.Children[0]->Level * Style.IndentWidth;
720
721 Penalty +=
722 BlockFormatter->format(Previous.Children, DryRun, AdditionalIndent,
6
←
Calling 'UnwrappedLineFormatter::format'
→
723 /*FixBadIndentation=*/true);
724 return true;
725 }
726
727 if (Previous.Children[0]->First->MustBreakBefore)
728 return false;
729
730 // Cannot merge into one line if this line ends on a comment.
731 if (Previous.is(tok::comment))
732 return false;
733
734 // Cannot merge multiple statements into a single line.
735 if (Previous.Children.size() > 1)
736 return false;
737
738 const AnnotatedLine *Child = Previous.Children[0];
739 // We can't put the closing "}" on a line with a trailing comment.
740 if (Child->Last->isTrailingComment())
741 return false;
742
743 // If the child line exceeds the column limit, we wouldn't want to merge it.
744 // We add +2 for the trailing " }".
745 if (Style.ColumnLimit > 0 &&
746 Child->Last->TotalLength + State.Column + 2 > Style.ColumnLimit)
747 return false;
748
749 if (!DryRun) {
750 Whitespaces->replaceWhitespace(
751 *Child->First, /*Newlines=*/0, /*Spaces=*/1,
752 /*StartOfTokenColumn=*/State.Column, State.Line->InPPDirective);
753 }
754 Penalty +=
755 formatLine(*Child, State.Column + 1, /*FirstStartColumn=*/0, DryRun);
756
757 State.Column += 1 + Child->Last->TotalLength;
758 return true;
759 }
760
761 ContinuationIndenter *Indenter;
762
763private:
764 WhitespaceManager *Whitespaces;
765 const FormatStyle &Style;
766 UnwrappedLineFormatter *BlockFormatter;
767};
768
769/// \brief Formatter that keeps the existing line breaks.
770class NoColumnLimitLineFormatter : public LineFormatter {
771public:
772 NoColumnLimitLineFormatter(ContinuationIndenter *Indenter,
773 WhitespaceManager *Whitespaces,
774 const FormatStyle &Style,
775 UnwrappedLineFormatter *BlockFormatter)
776 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
777
778 /// \brief Formats the line, simply keeping all of the input's line breaking
779 /// decisions.
780 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
781 unsigned FirstStartColumn, bool DryRun) override {
782 assert(!DryRun)(static_cast <bool> (!DryRun) ? void (0) : __assert_fail
("!DryRun", "/build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp"
, 782, __extension__ __PRETTY_FUNCTION__));
783 LineState State = Indenter->getInitialState(FirstIndent, FirstStartColumn,
784 &Line, /*DryRun=*/false);
785 while (State.NextToken) {
786 bool Newline =
787 Indenter->mustBreak(State) ||
788 (Indenter->canBreak(State) && State.NextToken->NewlinesBefore > 0);
789 unsigned Penalty = 0;
790 formatChildren(State, Newline, /*DryRun=*/false, Penalty);
791 Indenter->addTokenToState(State, Newline, /*DryRun=*/false);
792 }
793 return 0;
794 }
795};
796
797/// \brief Formatter that puts all tokens into a single line without breaks.
798class NoLineBreakFormatter : public LineFormatter {
799public:
800 NoLineBreakFormatter(ContinuationIndenter *Indenter,
801 WhitespaceManager *Whitespaces, const FormatStyle &Style,
802 UnwrappedLineFormatter *BlockFormatter)
803 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
804
805 /// \brief Puts all tokens into a single line.
806 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
807 unsigned FirstStartColumn, bool DryRun) override {
808 unsigned Penalty = 0;
809 LineState State =
810 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
811 while (State.NextToken) {
812 formatChildren(State, /*Newline=*/false, DryRun, Penalty);
813 Indenter->addTokenToState(
814 State, /*Newline=*/State.NextToken->MustBreakBefore, DryRun);
815 }
816 return Penalty;
817 }
818};
819
820/// \brief Finds the best way to break lines.
821class OptimizingLineFormatter : public LineFormatter {
822public:
823 OptimizingLineFormatter(ContinuationIndenter *Indenter,
824 WhitespaceManager *Whitespaces,
825 const FormatStyle &Style,
826 UnwrappedLineFormatter *BlockFormatter)
827 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
828
829 /// \brief Formats the line by finding the best line breaks with line lengths
830 /// below the column limit.
831 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
832 unsigned FirstStartColumn, bool DryRun) override {
833 LineState State =
834 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
835
836 // If the ObjC method declaration does not fit on a line, we should format
837 // it with one arg per line.
838 if (State.Line->Type == LT_ObjCMethodDecl)
839 State.Stack.back().BreakBeforeParameter = true;
840
841 // Find best solution in solution space.
842 return analyzeSolutionSpace(State, DryRun);
843 }
844
845private:
846 struct CompareLineStatePointers {
847 bool operator()(LineState *obj1, LineState *obj2) const {
848 return *obj1 < *obj2;
849 }
850 };
851
852 /// \brief A pair of <penalty, count> that is used to prioritize the BFS on.
853 ///
854 /// In case of equal penalties, we want to prefer states that were inserted
855 /// first. During state generation we make sure that we insert states first
856 /// that break the line as late as possible.
857 typedef std::pair<unsigned, unsigned> OrderedPenalty;
858
859 /// \brief An edge in the solution space from \c Previous->State to \c State,
860 /// inserting a newline dependent on the \c NewLine.
861 struct StateNode {
862 StateNode(const LineState &State, bool NewLine, StateNode *Previous)
863 : State(State), NewLine(NewLine), Previous(Previous) {}
864 LineState State;
865 bool NewLine;
866 StateNode *Previous;
867 };
868
869 /// \brief An item in the prioritized BFS search queue. The \c StateNode's
870 /// \c State has the given \c OrderedPenalty.
871 typedef std::pair<OrderedPenalty, StateNode *> QueueItem;
872
873 /// \brief The BFS queue type.
874 typedef std::priority_queue<QueueItem, std::vector<QueueItem>,
875 std::greater<QueueItem>>
876 QueueType;
877
878 /// \brief Analyze the entire solution space starting from \p InitialState.
879 ///
880 /// This implements a variant of Dijkstra's algorithm on the graph that spans
881 /// the solution space (\c LineStates are the nodes). The algorithm tries to
882 /// find the shortest path (the one with lowest penalty) from \p InitialState
883 /// to a state where all tokens are placed. Returns the penalty.
884 ///
885 /// If \p DryRun is \c false, directly applies the changes.
886 unsigned analyzeSolutionSpace(LineState &InitialState, bool DryRun) {
887 std::set<LineState *, CompareLineStatePointers> Seen;
888
889 // Increasing count of \c StateNode items we have created. This is used to
890 // create a deterministic order independent of the container.
891 unsigned Count = 0;
892 QueueType Queue;
893
894 // Insert start element into queue.
895 StateNode *Node =
896 new (Allocator.Allocate()) StateNode(InitialState, false, nullptr);
897 Queue.push(QueueItem(OrderedPenalty(0, Count), Node));
898 ++Count;
899
900 unsigned Penalty = 0;
901
902 // While not empty, take first element and follow edges.
903 while (!Queue.empty()) {
904 Penalty = Queue.top().first.first;
905 StateNode *Node = Queue.top().second;
906 if (!Node->State.NextToken) {
907 DEBUG(llvm::dbgs() << "\n---\nPenalty for line: " << Penalty << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { llvm::dbgs() << "\n---\nPenalty for line: "
<< Penalty << "\n"; } } while (false);
908 break;
909 }
910 Queue.pop();
911
912 // Cut off the analysis of certain solutions if the analysis gets too
913 // complex. See description of IgnoreStackForComparison.
914 if (Count > 50000)
915 Node->State.IgnoreStackForComparison = true;
916
917 if (!Seen.insert(&Node->State).second)
918 // State already examined with lower penalty.
919 continue;
920
921 FormatDecision LastFormat = Node->State.NextToken->Decision;
922 if (LastFormat == FD_Unformatted || LastFormat == FD_Continue)
923 addNextStateToQueue(Penalty, Node, /*NewLine=*/false, &Count, &Queue);
924 if (LastFormat == FD_Unformatted || LastFormat == FD_Break)
925 addNextStateToQueue(Penalty, Node, /*NewLine=*/true, &Count, &Queue);
926 }
927
928 if (Queue.empty()) {
929 // We were unable to find a solution, do nothing.
930 // FIXME: Add diagnostic?
931 DEBUG(llvm::dbgs() << "Could not find a solution.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { llvm::dbgs() << "Could not find a solution.\n"
; } } while (false);
932 return 0;
933 }
934
935 // Reconstruct the solution.
936 if (!DryRun)
937 reconstructPath(InitialState, Queue.top().second);
938
939 DEBUG(llvm::dbgs() << "Total number of analyzed states: " << Count << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { llvm::dbgs() << "Total number of analyzed states: "
<< Count << "\n"; } } while (false);
940 DEBUG(llvm::dbgs() << "---\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { llvm::dbgs() << "---\n"; } } while
(false);
941
942 return Penalty;
943 }
944
945 /// \brief Add the following state to the analysis queue \c Queue.
946 ///
947 /// Assume the current state is \p PreviousNode and has been reached with a
948 /// penalty of \p Penalty. Insert a line break if \p NewLine is \c true.
949 void addNextStateToQueue(unsigned Penalty, StateNode *PreviousNode,
950 bool NewLine, unsigned *Count, QueueType *Queue) {
951 if (NewLine && !Indenter->canBreak(PreviousNode->State))
952 return;
953 if (!NewLine && Indenter->mustBreak(PreviousNode->State))
954 return;
955
956 StateNode *Node = new (Allocator.Allocate())
957 StateNode(PreviousNode->State, NewLine, PreviousNode);
958 if (!formatChildren(Node->State, NewLine, /*DryRun=*/true, Penalty))
959 return;
960
961 Penalty += Indenter->addTokenToState(Node->State, NewLine, true);
962
963 Queue->push(QueueItem(OrderedPenalty(Penalty, *Count), Node));
964 ++(*Count);
965 }
966
967 /// \brief Applies the best formatting by reconstructing the path in the
968 /// solution space that leads to \c Best.
969 void reconstructPath(LineState &State, StateNode *Best) {
970 std::deque<StateNode *> Path;
971 // We do not need a break before the initial token.
972 while (Best->Previous) {
973 Path.push_front(Best);
974 Best = Best->Previous;
975 }
976 for (std::deque<StateNode *>::iterator I = Path.begin(), E = Path.end();
977 I != E; ++I) {
978 unsigned Penalty = 0;
979 formatChildren(State, (*I)->NewLine, /*DryRun=*/false, Penalty);
980 Penalty += Indenter->addTokenToState(State, (*I)->NewLine, false);
981
982 DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
983 printLineState((*I)->Previous->State);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
984 if ((*I)->NewLine) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
985 llvm::dbgs() << "Penalty for placing "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
986 << (*I)->Previous->State.NextToken->Tok.getName() << ": "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
987 << Penalty << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
988 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false)
989 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("format-formatter")) { { printLineState((*I)->Previous->
State); if ((*I)->NewLine) { llvm::dbgs() << "Penalty for placing "
<< (*I)->Previous->State.NextToken->Tok.getName
() << ": " << Penalty << "\n"; } }; } } while
(false);
990 }
991 }
992
993 llvm::SpecificBumpPtrAllocator<StateNode> Allocator;
994};
995
996} // anonymous namespace
997
998unsigned
999UnwrappedLineFormatter::format(const SmallVectorImpl<AnnotatedLine *> &Lines,
1000 bool DryRun, int AdditionalIndent,
1001 bool FixBadIndentation,
1002 unsigned FirstStartColumn,
1003 unsigned NextStartColumn,
1004 unsigned LastStartColumn) {
1005 LineJoiner Joiner(Style, Keywords, Lines);
1006
1007 // Try to look up already computed penalty in DryRun-mode.
1008 std::pair<const SmallVectorImpl<AnnotatedLine *> *, unsigned> CacheKey(
1009 &Lines, AdditionalIndent);
1010 auto CacheIt = PenaltyCache.find(CacheKey);
1011 if (DryRun && CacheIt != PenaltyCache.end())
7
←
Assuming 'DryRun' is 0
→
8
←
Taking false branch
→
18
←
Taking false branch
→
27
←
Taking false branch
→
1012 return CacheIt->second;
1013
1014 assert(!Lines.empty())(static_cast <bool> (!Lines.empty()) ? void (0) : __assert_fail
("!Lines.empty()", "/build/llvm-toolchain-snapshot-7~svn329677/tools/clang/lib/Format/UnwrappedLineFormatter.cpp"
, 1014, __extension__ __PRETTY_FUNCTION__));
1015 unsigned Penalty = 0;
1016 LevelIndentTracker IndentTracker(Style, Keywords, Lines[0]->Level,
1017 AdditionalIndent);
1018 const AnnotatedLine *PreviousLine = nullptr;
1019 const AnnotatedLine *NextLine = nullptr;
1020
1021 // The minimum level of consecutive lines that have been formatted.
1022 unsigned RangeMinLevel = UINT_MAX(2147483647 *2U +1U);
1023
1024 bool FirstLine = true;
1025 for (const AnnotatedLine *Line =
9
←
Loop condition is true. Entering loop body
→
19
←
Loop condition is true. Entering loop body
→
28
←
Loop condition is true. Entering loop body
→
1026 Joiner.getNextMergedLine(DryRun, IndentTracker);
1027 Line; Line = NextLine, FirstLine = false) {
1028 const AnnotatedLine &TheLine = *Line;
1029 unsigned Indent = IndentTracker.getIndent();
1030
1031 // We continue formatting unchanged lines to adjust their indent, e.g. if a
1032 // scope was added. However, we need to carefully stop doing this when we
1033 // exit the scope of affected lines to prevent indenting a the entire
1034 // remaining file if it currently missing a closing brace.
1035 bool ContinueFormatting =
1036 TheLine.Level > RangeMinLevel ||
1037 (TheLine.Level == RangeMinLevel && !TheLine.startsWith(tok::r_brace));
10
←
Assuming the condition is false
→
20
←
Assuming the condition is false
→
29
←
Assuming the condition is false
→
1038
1039 bool FixIndentation = (FixBadIndentation || ContinueFormatting) &&
1040 Indent != TheLine.First->OriginalColumn;
1041 bool ShouldFormat = TheLine.Affected || FixIndentation;
11
←
Assuming the condition is false
→
21
←
Assuming the condition is false
→
30
←
Assuming the condition is false
→
1042 // We cannot format this line; if the reason is that the line had a
1043 // parsing error, remember that.
1044 if (ShouldFormat && TheLine.Type == LT_Invalid && Status) {
12
←
Assuming 'ShouldFormat' is 0
→
1045 Status->FormatComplete = false;
1046 Status->Line =
1047 SourceMgr.getSpellingLineNumber(TheLine.First->Tok.getLocation());
1048 }
1049
1050 if (ShouldFormat && TheLine.Type != LT_Invalid) {
1051 if (!DryRun) {
1052 bool LastLine = Line->First->is(tok::eof);
1053 formatFirstToken(TheLine, PreviousLine,
1054 Indent,
1055 LastLine ? LastStartColumn : NextStartColumn + Indent);
1056 }
1057
1058 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1059 unsigned ColumnLimit = getColumnLimit(TheLine.InPPDirective, NextLine);
1060 bool FitsIntoOneLine =
1061 TheLine.Last->TotalLength + Indent <= ColumnLimit ||
1062 (TheLine.Type == LT_ImportStatement &&
1063 (Style.Language != FormatStyle::LK_JavaScript ||
1064 !Style.JavaScriptWrapImports));
1065 if (Style.ColumnLimit == 0)
1066 NoColumnLimitLineFormatter(Indenter, Whitespaces, Style, this)
1067 .formatLine(TheLine, NextStartColumn + Indent,
1068 FirstLine ? FirstStartColumn : 0, DryRun);
1069 else if (FitsIntoOneLine)
1070 Penalty += NoLineBreakFormatter(Indenter, Whitespaces, Style, this)
1071 .formatLine(TheLine, NextStartColumn + Indent,
1072 FirstLine ? FirstStartColumn : 0, DryRun);
1073 else
1074 Penalty += OptimizingLineFormatter(Indenter, Whitespaces, Style, this)
1075 .formatLine(TheLine, NextStartColumn + Indent,
1076 FirstLine ? FirstStartColumn : 0, DryRun);
1077 RangeMinLevel = std::min(RangeMinLevel, TheLine.Level);
1078 } else {
1079 // If no token in the current line is affected, we still need to format
1080 // affected children.
1081 if (TheLine.ChildrenAffected)
13
←
Assuming the condition is true
→
14
←
Taking true branch
→
22
←
Assuming the condition is true
→
23
←
Taking true branch
→
31
←
Assuming the condition is true
→
32
←
Taking true branch
→
1082 for (const FormatToken *Tok = TheLine.First; Tok; Tok = Tok->Next)
15
←
Loop condition is true. Entering loop body
→
24
←
Loop condition is true. Entering loop body
→
33
←
Assuming pointer value is null
→
34
←
Loop condition is false. Execution continues on line 1089
→
1083 if (!Tok->Children.empty())
16
←
Taking true branch
→
25
←
Taking true branch
→
1084 format(Tok->Children, DryRun);
17
←
Calling 'UnwrappedLineFormatter::format'
→
26
←
Calling 'UnwrappedLineFormatter::format'
→
1085
1086 // Adapt following lines on the current indent level to the same level
1087 // unless the current \c AnnotatedLine is not at the beginning of a line.
1088 bool StartsNewLine =
1089 TheLine.First->NewlinesBefore > 0 || TheLine.First->IsFirst;
35
←
Access to field 'NewlinesBefore' results in a dereference of a null pointer (loaded from field 'First')
1090 if (StartsNewLine)
1091 IndentTracker.adjustToUnmodifiedLine(TheLine);
1092 if (!DryRun) {
1093 bool ReformatLeadingWhitespace =
1094 StartsNewLine && ((PreviousLine && PreviousLine->Affected) ||
1095 TheLine.LeadingEmptyLinesAffected);
1096 // Format the first token.
1097 if (ReformatLeadingWhitespace)
1098 formatFirstToken(TheLine, PreviousLine,
1099 TheLine.First->OriginalColumn,
1100 TheLine.First->OriginalColumn);
1101 else
1102 Whitespaces->addUntouchableToken(*TheLine.First,
1103 TheLine.InPPDirective);
1104
1105 // Notify the WhitespaceManager about the unchanged whitespace.
1106 for (FormatToken *Tok = TheLine.First->Next; Tok; Tok = Tok->Next)
1107 Whitespaces->addUntouchableToken(*Tok, TheLine.InPPDirective);
1108 }
1109 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1110 RangeMinLevel = UINT_MAX(2147483647 *2U +1U);
1111 }
1112 if (!DryRun)
1113 markFinalized(TheLine.First);
1114 PreviousLine = &TheLine;
1115 }
1116 PenaltyCache[CacheKey] = Penalty;
1117 return Penalty;
1118}
1119
1120void UnwrappedLineFormatter::formatFirstToken(const AnnotatedLine &Line,
1121 const AnnotatedLine *PreviousLine,
1122 unsigned Indent,
1123 unsigned NewlineIndent) {
1124 FormatToken &RootToken = *Line.First;
1125 if (RootToken.is(tok::eof)) {
1126 unsigned Newlines = std::min(RootToken.NewlinesBefore, 1u);
1127 unsigned TokenIndent = Newlines ? NewlineIndent : 0;
1128 Whitespaces->replaceWhitespace(RootToken, Newlines, TokenIndent,
1129 TokenIndent);
1130 return;
1131 }
1132 unsigned Newlines =
1133 std::min(RootToken.NewlinesBefore, Style.MaxEmptyLinesToKeep + 1);
1134 // Remove empty lines before "}" where applicable.
1135 if (RootToken.is(tok::r_brace) &&
1136 (!RootToken.Next ||
1137 (RootToken.Next->is(tok::semi) && !RootToken.Next->Next)))
1138 Newlines = std::min(Newlines, 1u);
1139 // Remove empty lines at the start of nested blocks (lambdas/arrow functions)
1140 if (PreviousLine == nullptr && Line.Level > 0)
1141 Newlines = std::min(Newlines, 1u);
1142 if (Newlines == 0 && !RootToken.IsFirst)
1143 Newlines = 1;
1144 if (RootToken.IsFirst && !RootToken.HasUnescapedNewline)
1145 Newlines = 0;
1146
1147 // Remove empty lines after "{".
1148 if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine &&
1149 PreviousLine->Last->is(tok::l_brace) &&
1150 PreviousLine->First->isNot(tok::kw_namespace) &&
1151 !startsExternCBlock(*PreviousLine))
1152 Newlines = 1;
1153
1154 // Insert extra new line before access specifiers.
1155 if (PreviousLine && PreviousLine->Last->isOneOf(tok::semi, tok::r_brace) &&
1156 RootToken.isAccessSpecifier() && RootToken.NewlinesBefore == 1)
1157 ++Newlines;
1158
1159 // Remove empty lines after access specifiers.
1160 if (PreviousLine && PreviousLine->First->isAccessSpecifier() &&
1161 (!PreviousLine->InPPDirective || !RootToken.HasUnescapedNewline))
1162 Newlines = std::min(1u, Newlines);
1163
1164 if (Newlines)
1165 Indent = NewlineIndent;
1166
1167 // Preprocessor directives get indented after the hash, if indented.
1168 if (Line.Type == LT_PreprocessorDirective || Line.Type == LT_ImportStatement)
1169 Indent = 0;
1170
1171 Whitespaces->replaceWhitespace(RootToken, Newlines, Indent, Indent,
1172 Line.InPPDirective &&
1173 !RootToken.HasUnescapedNewline);
1174}
1175
1176unsigned
1177UnwrappedLineFormatter::getColumnLimit(bool InPPDirective,
1178 const AnnotatedLine *NextLine) const {
1179 // In preprocessor directives reserve two chars for trailing " \" if the
1180 // next line continues the preprocessor directive.
1181 bool ContinuesPPDirective =
1182 InPPDirective &&
1183 // If there is no next line, this is likely a child line and the parent
1184 // continues the preprocessor directive.
1185 (!NextLine ||
1186 (NextLine->InPPDirective &&
1187 // If there is an unescaped newline between this line and the next, the
1188 // next line starts a new preprocessor directive.
1189 !NextLine->First->HasUnescapedNewline));
1190 return Style.ColumnLimit - (ContinuesPPDirective ? 2 : 0);
1191}
1192
1193} // namespace format
1194} // namespace clang