Bug Summary

File:clang/lib/Format/UnwrappedLineFormatter.cpp
Warning:line 1103, column 7
Value stored to 'Penalty' is never read

Annotated Source Code

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clang -cc1 -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-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 -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Format -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Format -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Format -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/include -D NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/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-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Format -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-09-04-040900-46481-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Format/UnwrappedLineFormatter.cpp
1//===--- UnwrappedLineFormatter.cpp - Format C++ code ---------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "UnwrappedLineFormatter.h"
10#include "NamespaceEndCommentsFixer.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/// 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 /// Returns the indent for the current line.
49 unsigned getIndent() const { return Indent; }
50
51 /// 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 unsigned IndentWidth =
61 (Style.PPIndentWidth >= 0) ? Style.PPIndentWidth : Style.IndentWidth;
62 Indent = Line.Level * IndentWidth + AdditionalIndent;
63 } else {
64 IndentForLevel.resize(Line.Level + 1);
65 Indent = getIndent(IndentForLevel, Line.Level);
66 }
67 if (static_cast<int>(Indent) + Offset >= 0)
68 Indent += Offset;
69 if (Line.First->is(TT_CSharpGenericTypeConstraint))
70 Indent = Line.Level * Style.IndentWidth + Style.ContinuationIndentWidth;
71 }
72
73 /// Update the indent state given that \p Line indent should be
74 /// skipped.
75 void skipLine(const AnnotatedLine &Line) {
76 while (IndentForLevel.size() <= Line.Level)
77 IndentForLevel.push_back(Indent);
78 }
79
80 /// Update the level indent to adapt to the given \p Line.
81 ///
82 /// When a line is not formatted, we move the subsequent lines on the same
83 /// level to the same indent.
84 /// Note that \c nextLine must have been called before this method.
85 void adjustToUnmodifiedLine(const AnnotatedLine &Line) {
86 unsigned LevelIndent = Line.First->OriginalColumn;
87 if (static_cast<int>(LevelIndent) - Offset >= 0)
88 LevelIndent -= Offset;
89 if ((!Line.First->is(tok::comment) || IndentForLevel[Line.Level] == -1) &&
90 !Line.InPPDirective)
91 IndentForLevel[Line.Level] = LevelIndent;
92 }
93
94private:
95 /// Get the offset of the line relatively to the level.
96 ///
97 /// For example, 'public:' labels in classes are offset by 1 or 2
98 /// characters to the left from their level.
99 int getIndentOffset(const FormatToken &RootToken) {
100 if (Style.Language == FormatStyle::LK_Java ||
101 Style.Language == FormatStyle::LK_JavaScript || Style.isCSharp())
102 return 0;
103 if (RootToken.isAccessSpecifier(false) ||
104 RootToken.isObjCAccessSpecifier() ||
105 (RootToken.isOneOf(Keywords.kw_signals, Keywords.kw_qsignals) &&
106 RootToken.Next && RootToken.Next->is(tok::colon))) {
107 // The AccessModifierOffset may be overriden by IndentAccessModifiers,
108 // in which case we take a negative value of the IndentWidth to simulate
109 // the upper indent level.
110 return Style.IndentAccessModifiers ? -Style.IndentWidth
111 : Style.AccessModifierOffset;
112 }
113 return 0;
114 }
115
116 /// Get the indent of \p Level from \p IndentForLevel.
117 ///
118 /// \p IndentForLevel must contain the indent for the level \c l
119 /// at \p IndentForLevel[l], or a value < 0 if the indent for
120 /// that level is unknown.
121 unsigned getIndent(ArrayRef<int> IndentForLevel, unsigned Level) {
122 if (IndentForLevel[Level] != -1)
123 return IndentForLevel[Level];
124 if (Level == 0)
125 return 0;
126 return getIndent(IndentForLevel, Level - 1) + Style.IndentWidth;
127 }
128
129 const FormatStyle &Style;
130 const AdditionalKeywords &Keywords;
131 const unsigned AdditionalIndent;
132
133 /// The indent in characters for each level.
134 std::vector<int> IndentForLevel;
135
136 /// Offset of the current line relative to the indent level.
137 ///
138 /// For example, the 'public' keywords is often indented with a negative
139 /// offset.
140 int Offset = 0;
141
142 /// The current line's indent.
143 unsigned Indent = 0;
144};
145
146const FormatToken *getMatchingNamespaceToken(
147 const AnnotatedLine *Line,
148 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
149 if (!Line->startsWith(tok::r_brace))
150 return nullptr;
151 size_t StartLineIndex = Line->MatchingOpeningBlockLineIndex;
152 if (StartLineIndex == UnwrappedLine::kInvalidIndex)
153 return nullptr;
154 assert(StartLineIndex < AnnotatedLines.size())(static_cast<void> (0));
155 return AnnotatedLines[StartLineIndex]->First->getNamespaceToken();
156}
157
158StringRef getNamespaceTokenText(const AnnotatedLine *Line) {
159 const FormatToken *NamespaceToken = Line->First->getNamespaceToken();
160 return NamespaceToken ? NamespaceToken->TokenText : StringRef();
161}
162
163StringRef getMatchingNamespaceTokenText(
164 const AnnotatedLine *Line,
165 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
166 const FormatToken *NamespaceToken =
167 getMatchingNamespaceToken(Line, AnnotatedLines);
168 return NamespaceToken ? NamespaceToken->TokenText : StringRef();
169}
170
171class LineJoiner {
172public:
173 LineJoiner(const FormatStyle &Style, const AdditionalKeywords &Keywords,
174 const SmallVectorImpl<AnnotatedLine *> &Lines)
175 : Style(Style), Keywords(Keywords), End(Lines.end()), Next(Lines.begin()),
176 AnnotatedLines(Lines) {}
177
178 /// Returns the next line, merging multiple lines into one if possible.
179 const AnnotatedLine *getNextMergedLine(bool DryRun,
180 LevelIndentTracker &IndentTracker) {
181 if (Next == End)
182 return nullptr;
183 const AnnotatedLine *Current = *Next;
184 IndentTracker.nextLine(*Current);
185 unsigned MergedLines = tryFitMultipleLinesInOne(IndentTracker, Next, End);
186 if (MergedLines > 0 && Style.ColumnLimit == 0)
187 // Disallow line merging if there is a break at the start of one of the
188 // input lines.
189 for (unsigned i = 0; i < MergedLines; ++i)
190 if (Next[i + 1]->First->NewlinesBefore > 0)
191 MergedLines = 0;
192 if (!DryRun)
193 for (unsigned i = 0; i < MergedLines; ++i)
194 join(*Next[0], *Next[i + 1]);
195 Next = Next + MergedLines + 1;
196 return Current;
197 }
198
199private:
200 /// Calculates how many lines can be merged into 1 starting at \p I.
201 unsigned
202 tryFitMultipleLinesInOne(LevelIndentTracker &IndentTracker,
203 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
204 SmallVectorImpl<AnnotatedLine *>::const_iterator E) {
205 const unsigned Indent = IndentTracker.getIndent();
206
207 // Can't join the last line with anything.
208 if (I + 1 == E)
209 return 0;
210 // We can never merge stuff if there are trailing line comments.
211 const AnnotatedLine *TheLine = *I;
212 if (TheLine->Last->is(TT_LineComment))
213 return 0;
214 if (I[1]->Type == LT_Invalid || I[1]->First->MustBreakBefore)
215 return 0;
216 if (TheLine->InPPDirective &&
217 (!I[1]->InPPDirective || I[1]->First->HasUnescapedNewline))
218 return 0;
219
220 if (Style.ColumnLimit > 0 && Indent > Style.ColumnLimit)
221 return 0;
222
223 unsigned Limit =
224 Style.ColumnLimit == 0 ? UINT_MAX(2147483647 *2U +1U) : Style.ColumnLimit - Indent;
225 // If we already exceed the column limit, we set 'Limit' to 0. The different
226 // tryMerge..() functions can then decide whether to still do merging.
227 Limit = TheLine->Last->TotalLength > Limit
228 ? 0
229 : Limit - TheLine->Last->TotalLength;
230
231 if (TheLine->Last->is(TT_FunctionLBrace) &&
232 TheLine->First == TheLine->Last &&
233 !Style.BraceWrapping.SplitEmptyFunction &&
234 I[1]->First->is(tok::r_brace))
235 return tryMergeSimpleBlock(I, E, Limit);
236
237 // Handle empty record blocks where the brace has already been wrapped
238 if (TheLine->Last->is(tok::l_brace) && TheLine->First == TheLine->Last &&
239 I != AnnotatedLines.begin()) {
240 bool EmptyBlock = I[1]->First->is(tok::r_brace);
241
242 const FormatToken *Tok = I[-1]->First;
243 if (Tok && Tok->is(tok::comment))
244 Tok = Tok->getNextNonComment();
245
246 if (Tok && Tok->getNamespaceToken())
247 return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock
248 ? tryMergeSimpleBlock(I, E, Limit)
249 : 0;
250
251 if (Tok && Tok->is(tok::kw_typedef))
252 Tok = Tok->getNextNonComment();
253 if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
254 tok::kw_extern, Keywords.kw_interface))
255 return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
256 ? tryMergeSimpleBlock(I, E, Limit)
257 : 0;
258
259 if (Tok && Tok->is(tok::kw_template) &&
260 Style.BraceWrapping.SplitEmptyRecord && EmptyBlock) {
261 return 0;
262 }
263 }
264
265 // FIXME: TheLine->Level != 0 might or might not be the right check to do.
266 // If necessary, change to something smarter.
267 bool MergeShortFunctions =
268 Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_All ||
269 (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
270 I[1]->First->is(tok::r_brace)) ||
271 (Style.AllowShortFunctionsOnASingleLine & FormatStyle::SFS_InlineOnly &&
272 TheLine->Level != 0);
273
274 if (Style.CompactNamespaces) {
275 if (auto nsToken = TheLine->First->getNamespaceToken()) {
276 int i = 0;
277 unsigned closingLine = TheLine->MatchingClosingBlockLineIndex - 1;
278 for (; I + 1 + i != E &&
279 nsToken->TokenText == getNamespaceTokenText(I[i + 1]) &&
280 closingLine == I[i + 1]->MatchingClosingBlockLineIndex &&
281 I[i + 1]->Last->TotalLength < Limit;
282 i++, closingLine--) {
283 // No extra indent for compacted namespaces
284 IndentTracker.skipLine(*I[i + 1]);
285
286 Limit -= I[i + 1]->Last->TotalLength;
287 }
288 return i;
289 }
290
291 if (auto nsToken = getMatchingNamespaceToken(TheLine, AnnotatedLines)) {
292 int i = 0;
293 unsigned openingLine = TheLine->MatchingOpeningBlockLineIndex - 1;
294 for (; I + 1 + i != E &&
295 nsToken->TokenText ==
296 getMatchingNamespaceTokenText(I[i + 1], AnnotatedLines) &&
297 openingLine == I[i + 1]->MatchingOpeningBlockLineIndex;
298 i++, openingLine--) {
299 // No space between consecutive braces
300 I[i + 1]->First->SpacesRequiredBefore = !I[i]->Last->is(tok::r_brace);
301
302 // Indent like the outer-most namespace
303 IndentTracker.nextLine(*I[i + 1]);
304 }
305 return i;
306 }
307 }
308
309 // Try to merge a function block with left brace unwrapped
310 if (TheLine->Last->is(TT_FunctionLBrace) &&
311 TheLine->First != TheLine->Last) {
312 return MergeShortFunctions ? tryMergeSimpleBlock(I, E, Limit) : 0;
313 }
314 // Try to merge a control statement block with left brace unwrapped
315 if (TheLine->Last->is(tok::l_brace) && TheLine->First != TheLine->Last &&
316 TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for)) {
317 return Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never
318 ? tryMergeSimpleBlock(I, E, Limit)
319 : 0;
320 }
321 // Try to merge a control statement block with left brace wrapped
322 if (I[1]->First->is(tok::l_brace) &&
323 (TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for,
324 tok::kw_switch, tok::kw_try, tok::kw_do,
325 TT_ForEachMacro) ||
326 (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
327 TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
328 Style.BraceWrapping.AfterControlStatement ==
329 FormatStyle::BWACS_MultiLine) {
330 // If possible, merge the next line's wrapped left brace with the current
331 // line. Otherwise, leave it on the next line, as this is a multi-line
332 // control statement.
333 return (Style.ColumnLimit == 0 ||
334 TheLine->Last->TotalLength <= Style.ColumnLimit)
335 ? 1
336 : 0;
337 } else if (I[1]->First->is(tok::l_brace) &&
338 TheLine->First->isOneOf(tok::kw_if, tok::kw_while,
339 tok::kw_for)) {
340 return (Style.BraceWrapping.AfterControlStatement ==
341 FormatStyle::BWACS_Always)
342 ? tryMergeSimpleBlock(I, E, Limit)
343 : 0;
344 } else if (I[1]->First->is(tok::l_brace) &&
345 TheLine->First->isOneOf(tok::kw_else, tok::kw_catch) &&
346 Style.BraceWrapping.AfterControlStatement ==
347 FormatStyle::BWACS_MultiLine) {
348 // This case if different from the upper BWACS_MultiLine processing
349 // in that a preceding r_brace is not on the same line as else/catch
350 // most likely because of BeforeElse/BeforeCatch set to true.
351 // If the line length doesn't fit ColumnLimit, leave l_brace on the
352 // next line to respect the BWACS_MultiLine.
353 return (Style.ColumnLimit == 0 ||
354 TheLine->Last->TotalLength <= Style.ColumnLimit)
355 ? 1
356 : 0;
357 }
358 // Don't merge block with left brace wrapped after ObjC special blocks
359 if (TheLine->First->is(tok::l_brace) && I != AnnotatedLines.begin() &&
360 I[-1]->First->is(tok::at) && I[-1]->First->Next) {
361 tok::ObjCKeywordKind kwId = I[-1]->First->Next->Tok.getObjCKeywordID();
362 if (kwId == clang::tok::objc_autoreleasepool ||
363 kwId == clang::tok::objc_synchronized)
364 return 0;
365 }
366 // Don't merge block with left brace wrapped after case labels
367 if (TheLine->First->is(tok::l_brace) && I != AnnotatedLines.begin() &&
368 I[-1]->First->isOneOf(tok::kw_case, tok::kw_default))
369 return 0;
370
371 // Don't merge an empty template class or struct if SplitEmptyRecords
372 // is defined.
373 if (Style.BraceWrapping.SplitEmptyRecord &&
374 TheLine->Last->is(tok::l_brace) && I != AnnotatedLines.begin() &&
375 I[-1]->Last) {
376 const FormatToken *Previous = I[-1]->Last;
377 if (Previous) {
378 if (Previous->is(tok::comment))
379 Previous = Previous->getPreviousNonComment();
380 if (Previous) {
381 if (Previous->is(tok::greater) && !I[-1]->InPPDirective)
382 return 0;
383 if (Previous->is(tok::identifier)) {
384 const FormatToken *PreviousPrevious =
385 Previous->getPreviousNonComment();
386 if (PreviousPrevious &&
387 PreviousPrevious->isOneOf(tok::kw_class, tok::kw_struct))
388 return 0;
389 }
390 }
391 }
392 }
393
394 // Try to merge a block with left brace wrapped that wasn't yet covered
395 if (TheLine->Last->is(tok::l_brace)) {
396 return !Style.BraceWrapping.AfterFunction ||
397 (I[1]->First->is(tok::r_brace) &&
398 !Style.BraceWrapping.SplitEmptyRecord)
399 ? tryMergeSimpleBlock(I, E, Limit)
400 : 0;
401 }
402 // Try to merge a function block with left brace wrapped
403 if (I[1]->First->is(TT_FunctionLBrace) &&
404 Style.BraceWrapping.AfterFunction) {
405 if (I[1]->Last->is(TT_LineComment))
406 return 0;
407
408 // Check for Limit <= 2 to account for the " {".
409 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(TheLine)))
410 return 0;
411 Limit -= 2;
412
413 unsigned MergedLines = 0;
414 if (MergeShortFunctions ||
415 (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
416 I[1]->First == I[1]->Last && I + 2 != E &&
417 I[2]->First->is(tok::r_brace))) {
418 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
419 // If we managed to merge the block, count the function header, which is
420 // on a separate line.
421 if (MergedLines > 0)
422 ++MergedLines;
423 }
424 return MergedLines;
425 }
426 auto IsElseLine = [&TheLine]() -> bool {
427 const FormatToken *First = TheLine->First;
428 if (First->is(tok::kw_else))
429 return true;
430
431 return First->is(tok::r_brace) && First->Next &&
432 First->Next->is(tok::kw_else);
433 };
434 if (TheLine->First->is(tok::kw_if) ||
435 (IsElseLine() && (Style.AllowShortIfStatementsOnASingleLine ==
436 FormatStyle::SIS_AllIfsAndElse))) {
437 return Style.AllowShortIfStatementsOnASingleLine
438 ? tryMergeSimpleControlStatement(I, E, Limit)
439 : 0;
440 }
441 if (TheLine->First->isOneOf(tok::kw_for, tok::kw_while, tok::kw_do)) {
442 return Style.AllowShortLoopsOnASingleLine
443 ? tryMergeSimpleControlStatement(I, E, Limit)
444 : 0;
445 }
446 if (TheLine->First->isOneOf(tok::kw_case, tok::kw_default)) {
447 return Style.AllowShortCaseLabelsOnASingleLine
448 ? tryMergeShortCaseLabels(I, E, Limit)
449 : 0;
450 }
451 if (TheLine->InPPDirective &&
452 (TheLine->First->HasUnescapedNewline || TheLine->First->IsFirst)) {
453 return tryMergeSimplePPDirective(I, E, Limit);
454 }
455 return 0;
456 }
457
458 unsigned
459 tryMergeSimplePPDirective(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
460 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
461 unsigned Limit) {
462 if (Limit == 0)
463 return 0;
464 if (I + 2 != E && I[2]->InPPDirective && !I[2]->First->HasUnescapedNewline)
465 return 0;
466 if (1 + I[1]->Last->TotalLength > Limit)
467 return 0;
468 return 1;
469 }
470
471 unsigned tryMergeSimpleControlStatement(
472 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
473 SmallVectorImpl<AnnotatedLine *>::const_iterator E, unsigned Limit) {
474 if (Limit == 0)
475 return 0;
476 if (Style.BraceWrapping.AfterControlStatement ==
477 FormatStyle::BWACS_Always &&
478 I[1]->First->is(tok::l_brace) &&
479 Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never)
480 return 0;
481 if (I[1]->InPPDirective != (*I)->InPPDirective ||
482 (I[1]->InPPDirective && I[1]->First->HasUnescapedNewline))
483 return 0;
484 Limit = limitConsideringMacros(I + 1, E, Limit);
485 AnnotatedLine &Line = **I;
486 if (!Line.First->is(tok::kw_do) && !Line.First->is(tok::kw_else) &&
487 !Line.Last->is(tok::kw_else) && Line.Last->isNot(tok::r_paren))
488 return 0;
489 // Only merge do while if do is the only statement on the line.
490 if (Line.First->is(tok::kw_do) && !Line.Last->is(tok::kw_do))
491 return 0;
492 if (1 + I[1]->Last->TotalLength > Limit)
493 return 0;
494 if (I[1]->First->isOneOf(tok::semi, tok::kw_if, tok::kw_for, tok::kw_while,
495 TT_LineComment))
496 return 0;
497 // Only inline simple if's (no nested if or else), unless specified
498 if (Style.AllowShortIfStatementsOnASingleLine ==
499 FormatStyle::SIS_WithoutElse) {
500 if (I + 2 != E && Line.startsWith(tok::kw_if) &&
501 I[2]->First->is(tok::kw_else))
502 return 0;
503 }
504 return 1;
505 }
506
507 unsigned
508 tryMergeShortCaseLabels(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
509 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
510 unsigned Limit) {
511 if (Limit == 0 || I + 1 == E ||
512 I[1]->First->isOneOf(tok::kw_case, tok::kw_default))
513 return 0;
514 if (I[0]->Last->is(tok::l_brace) || I[1]->First->is(tok::l_brace))
515 return 0;
516 unsigned NumStmts = 0;
517 unsigned Length = 0;
518 bool EndsWithComment = false;
519 bool InPPDirective = I[0]->InPPDirective;
520 const unsigned Level = I[0]->Level;
521 for (; NumStmts < 3; ++NumStmts) {
522 if (I + 1 + NumStmts == E)
523 break;
524 const AnnotatedLine *Line = I[1 + NumStmts];
525 if (Line->InPPDirective != InPPDirective)
526 break;
527 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
528 break;
529 if (Line->First->isOneOf(tok::kw_if, tok::kw_for, tok::kw_switch,
530 tok::kw_while) ||
531 EndsWithComment)
532 return 0;
533 if (Line->First->is(tok::comment)) {
534 if (Level != Line->Level)
535 return 0;
536 SmallVectorImpl<AnnotatedLine *>::const_iterator J = I + 2 + NumStmts;
537 for (; J != E; ++J) {
538 Line = *J;
539 if (Line->InPPDirective != InPPDirective)
540 break;
541 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
542 break;
543 if (Line->First->isNot(tok::comment) || Level != Line->Level)
544 return 0;
545 }
546 break;
547 }
548 if (Line->Last->is(tok::comment))
549 EndsWithComment = true;
550 Length += I[1 + NumStmts]->Last->TotalLength + 1; // 1 for the space.
551 }
552 if (NumStmts == 0 || NumStmts == 3 || Length > Limit)
553 return 0;
554 return NumStmts;
555 }
556
557 unsigned
558 tryMergeSimpleBlock(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
559 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
560 unsigned Limit) {
561 AnnotatedLine &Line = **I;
562
563 // Don't merge ObjC @ keywords and methods.
564 // FIXME: If an option to allow short exception handling clauses on a single
565 // line is added, change this to not return for @try and friends.
566 if (Style.Language != FormatStyle::LK_Java &&
567 Line.First->isOneOf(tok::at, tok::minus, tok::plus))
568 return 0;
569
570 // Check that the current line allows merging. This depends on whether we
571 // are in a control flow statements as well as several style flags.
572 if (Line.First->isOneOf(tok::kw_else, tok::kw_case) ||
573 (Line.First->Next && Line.First->Next->is(tok::kw_else)))
574 return 0;
575 // default: in switch statement
576 if (Line.First->is(tok::kw_default)) {
577 const FormatToken *Tok = Line.First->getNextNonComment();
578 if (Tok && Tok->is(tok::colon))
579 return 0;
580 }
581 if (Line.First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_do, tok::kw_try,
582 tok::kw___try, tok::kw_catch, tok::kw___finally,
583 tok::kw_for, tok::r_brace, Keywords.kw___except)) {
584 if (Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never)
585 return 0;
586 // Don't merge when we can't except the case when
587 // the control statement block is empty
588 if (!Style.AllowShortIfStatementsOnASingleLine &&
589 Line.startsWith(tok::kw_if) &&
590 !Style.BraceWrapping.AfterControlStatement &&
591 !I[1]->First->is(tok::r_brace))
592 return 0;
593 if (!Style.AllowShortIfStatementsOnASingleLine &&
594 Line.startsWith(tok::kw_if) &&
595 Style.BraceWrapping.AfterControlStatement ==
596 FormatStyle::BWACS_Always &&
597 I + 2 != E && !I[2]->First->is(tok::r_brace))
598 return 0;
599 if (!Style.AllowShortLoopsOnASingleLine &&
600 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
601 !Style.BraceWrapping.AfterControlStatement &&
602 !I[1]->First->is(tok::r_brace))
603 return 0;
604 if (!Style.AllowShortLoopsOnASingleLine &&
605 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
606 Style.BraceWrapping.AfterControlStatement ==
607 FormatStyle::BWACS_Always &&
608 I + 2 != E && !I[2]->First->is(tok::r_brace))
609 return 0;
610 // FIXME: Consider an option to allow short exception handling clauses on
611 // a single line.
612 // FIXME: This isn't covered by tests.
613 // FIXME: For catch, __except, __finally the first token on the line
614 // is '}', so this isn't correct here.
615 if (Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch,
616 Keywords.kw___except, tok::kw___finally))
617 return 0;
618 }
619
620 if (Line.Last->is(tok::l_brace)) {
621 FormatToken *Tok = I[1]->First;
622 if (Tok->is(tok::r_brace) && !Tok->MustBreakBefore &&
623 (Tok->getNextNonComment() == nullptr ||
624 Tok->getNextNonComment()->is(tok::semi))) {
625 // We merge empty blocks even if the line exceeds the column limit.
626 Tok->SpacesRequiredBefore = Style.SpaceInEmptyBlock ? 1 : 0;
627 Tok->CanBreakBefore = true;
628 return 1;
629 } else if (Limit != 0 && !Line.startsWithNamespace() &&
630 !startsExternCBlock(Line)) {
631 // We don't merge short records.
632 FormatToken *RecordTok = Line.First;
633 // Skip record modifiers.
634 while (RecordTok->Next &&
635 RecordTok->isOneOf(tok::kw_typedef, tok::kw_export,
636 Keywords.kw_declare, Keywords.kw_abstract,
637 tok::kw_default, Keywords.kw_override,
638 tok::kw_public, tok::kw_private,
639 tok::kw_protected, Keywords.kw_internal))
640 RecordTok = RecordTok->Next;
641 if (RecordTok &&
642 RecordTok->isOneOf(tok::kw_class, tok::kw_union, tok::kw_struct,
643 Keywords.kw_interface))
644 return 0;
645
646 // Check that we still have three lines and they fit into the limit.
647 if (I + 2 == E || I[2]->Type == LT_Invalid)
648 return 0;
649 Limit = limitConsideringMacros(I + 2, E, Limit);
650
651 if (!nextTwoLinesFitInto(I, Limit))
652 return 0;
653
654 // Second, check that the next line does not contain any braces - if it
655 // does, readability declines when putting it into a single line.
656 if (I[1]->Last->is(TT_LineComment))
657 return 0;
658 do {
659 if (Tok->is(tok::l_brace) && Tok->isNot(BK_BracedInit))
660 return 0;
661 Tok = Tok->Next;
662 } while (Tok);
663
664 // Last, check that the third line starts with a closing brace.
665 Tok = I[2]->First;
666 if (Tok->isNot(tok::r_brace))
667 return 0;
668
669 // Don't merge "if (a) { .. } else {".
670 if (Tok->Next && Tok->Next->is(tok::kw_else))
671 return 0;
672
673 // Don't merge a trailing multi-line control statement block like:
674 // } else if (foo &&
675 // bar)
676 // { <-- current Line
677 // baz();
678 // }
679 if (Line.First == Line.Last &&
680 Style.BraceWrapping.AfterControlStatement ==
681 FormatStyle::BWACS_MultiLine)
682 return 0;
683
684 return 2;
685 }
686 } else if (I[1]->First->is(tok::l_brace)) {
687 if (I[1]->Last->is(TT_LineComment))
688 return 0;
689
690 // Check for Limit <= 2 to account for the " {".
691 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(*I)))
692 return 0;
693 Limit -= 2;
694 unsigned MergedLines = 0;
695 if (Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never ||
696 (I[1]->First == I[1]->Last && I + 2 != E &&
697 I[2]->First->is(tok::r_brace))) {
698 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
699 // If we managed to merge the block, count the statement header, which
700 // is on a separate line.
701 if (MergedLines > 0)
702 ++MergedLines;
703 }
704 return MergedLines;
705 }
706 return 0;
707 }
708
709 /// Returns the modified column limit for \p I if it is inside a macro and
710 /// needs a trailing '\'.
711 unsigned
712 limitConsideringMacros(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
713 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
714 unsigned Limit) {
715 if (I[0]->InPPDirective && I + 1 != E &&
716 !I[1]->First->HasUnescapedNewline && !I[1]->First->is(tok::eof)) {
717 return Limit < 2 ? 0 : Limit - 2;
718 }
719 return Limit;
720 }
721
722 bool nextTwoLinesFitInto(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
723 unsigned Limit) {
724 if (I[1]->First->MustBreakBefore || I[2]->First->MustBreakBefore)
725 return false;
726 return 1 + I[1]->Last->TotalLength + 1 + I[2]->Last->TotalLength <= Limit;
727 }
728
729 bool containsMustBreak(const AnnotatedLine *Line) {
730 for (const FormatToken *Tok = Line->First; Tok; Tok = Tok->Next) {
731 if (Tok->MustBreakBefore)
732 return true;
733 }
734 return false;
735 }
736
737 void join(AnnotatedLine &A, const AnnotatedLine &B) {
738 assert(!A.Last->Next)(static_cast<void> (0));
739 assert(!B.First->Previous)(static_cast<void> (0));
740 if (B.Affected)
741 A.Affected = true;
742 A.Last->Next = B.First;
743 B.First->Previous = A.Last;
744 B.First->CanBreakBefore = true;
745 unsigned LengthA = A.Last->TotalLength + B.First->SpacesRequiredBefore;
746 for (FormatToken *Tok = B.First; Tok; Tok = Tok->Next) {
747 Tok->TotalLength += LengthA;
748 A.Last = Tok;
749 }
750 }
751
752 const FormatStyle &Style;
753 const AdditionalKeywords &Keywords;
754 const SmallVectorImpl<AnnotatedLine *>::const_iterator End;
755
756 SmallVectorImpl<AnnotatedLine *>::const_iterator Next;
757 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines;
758};
759
760static void markFinalized(FormatToken *Tok) {
761 for (; Tok; Tok = Tok->Next) {
762 Tok->Finalized = true;
763 for (AnnotatedLine *Child : Tok->Children)
764 markFinalized(Child->First);
765 }
766}
767
768#ifndef NDEBUG1
769static void printLineState(const LineState &State) {
770 llvm::dbgs() << "State: ";
771 for (const ParenState &P : State.Stack) {
772 llvm::dbgs() << (P.Tok ? P.Tok->TokenText : "F") << "|" << P.Indent << "|"
773 << P.LastSpace << "|" << P.NestedBlockIndent << " ";
774 }
775 llvm::dbgs() << State.NextToken->TokenText << "\n";
776}
777#endif
778
779/// Base class for classes that format one \c AnnotatedLine.
780class LineFormatter {
781public:
782 LineFormatter(ContinuationIndenter *Indenter, WhitespaceManager *Whitespaces,
783 const FormatStyle &Style,
784 UnwrappedLineFormatter *BlockFormatter)
785 : Indenter(Indenter), Whitespaces(Whitespaces), Style(Style),
786 BlockFormatter(BlockFormatter) {}
787 virtual ~LineFormatter() {}
788
789 /// Formats an \c AnnotatedLine and returns the penalty.
790 ///
791 /// If \p DryRun is \c false, directly applies the changes.
792 virtual unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
793 unsigned FirstStartColumn, bool DryRun) = 0;
794
795protected:
796 /// If the \p State's next token is an r_brace closing a nested block,
797 /// format the nested block before it.
798 ///
799 /// Returns \c true if all children could be placed successfully and adapts
800 /// \p Penalty as well as \p State. If \p DryRun is false, also directly
801 /// creates changes using \c Whitespaces.
802 ///
803 /// The crucial idea here is that children always get formatted upon
804 /// encountering the closing brace right after the nested block. Now, if we
805 /// are currently trying to keep the "}" on the same line (i.e. \p NewLine is
806 /// \c false), the entire block has to be kept on the same line (which is only
807 /// possible if it fits on the line, only contains a single statement, etc.
808 ///
809 /// If \p NewLine is true, we format the nested block on separate lines, i.e.
810 /// break after the "{", format all lines with correct indentation and the put
811 /// the closing "}" on yet another new line.
812 ///
813 /// This enables us to keep the simple structure of the
814 /// \c UnwrappedLineFormatter, where we only have two options for each token:
815 /// break or don't break.
816 bool formatChildren(LineState &State, bool NewLine, bool DryRun,
817 unsigned &Penalty) {
818 const FormatToken *LBrace = State.NextToken->getPreviousNonComment();
819 FormatToken &Previous = *State.NextToken->Previous;
820 if (!LBrace || LBrace->isNot(tok::l_brace) || LBrace->isNot(BK_Block) ||
821 Previous.Children.size() == 0)
822 // The previous token does not open a block. Nothing to do. We don't
823 // assert so that we can simply call this function for all tokens.
824 return true;
825
826 if (NewLine) {
827 const ParenState &P = State.Stack.back();
828
829 int AdditionalIndent =
830 P.Indent - Previous.Children[0]->Level * Style.IndentWidth;
831
832 if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
833 P.NestedBlockIndent == P.LastSpace) {
834 if (State.NextToken->MatchingParen &&
835 State.NextToken->MatchingParen->is(TT_LambdaLBrace)) {
836 State.Stack.pop_back();
837 }
838 if (LBrace->is(TT_LambdaLBrace))
839 AdditionalIndent = 0;
840 }
841
842 Penalty +=
843 BlockFormatter->format(Previous.Children, DryRun, AdditionalIndent,
844 /*FixBadIndentation=*/true);
845 return true;
846 }
847
848 if (Previous.Children[0]->First->MustBreakBefore)
849 return false;
850
851 // Cannot merge into one line if this line ends on a comment.
852 if (Previous.is(tok::comment))
853 return false;
854
855 // Cannot merge multiple statements into a single line.
856 if (Previous.Children.size() > 1)
857 return false;
858
859 const AnnotatedLine *Child = Previous.Children[0];
860 // We can't put the closing "}" on a line with a trailing comment.
861 if (Child->Last->isTrailingComment())
862 return false;
863
864 // If the child line exceeds the column limit, we wouldn't want to merge it.
865 // We add +2 for the trailing " }".
866 if (Style.ColumnLimit > 0 &&
867 Child->Last->TotalLength + State.Column + 2 > Style.ColumnLimit)
868 return false;
869
870 if (!DryRun) {
871 Whitespaces->replaceWhitespace(
872 *Child->First, /*Newlines=*/0, /*Spaces=*/1,
873 /*StartOfTokenColumn=*/State.Column, /*IsAligned=*/false,
874 State.Line->InPPDirective);
875 }
876 Penalty +=
877 formatLine(*Child, State.Column + 1, /*FirstStartColumn=*/0, DryRun);
878
879 State.Column += 1 + Child->Last->TotalLength;
880 return true;
881 }
882
883 ContinuationIndenter *Indenter;
884
885private:
886 WhitespaceManager *Whitespaces;
887 const FormatStyle &Style;
888 UnwrappedLineFormatter *BlockFormatter;
889};
890
891/// Formatter that keeps the existing line breaks.
892class NoColumnLimitLineFormatter : public LineFormatter {
893public:
894 NoColumnLimitLineFormatter(ContinuationIndenter *Indenter,
895 WhitespaceManager *Whitespaces,
896 const FormatStyle &Style,
897 UnwrappedLineFormatter *BlockFormatter)
898 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
899
900 /// Formats the line, simply keeping all of the input's line breaking
901 /// decisions.
902 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
903 unsigned FirstStartColumn, bool DryRun) override {
904 assert(!DryRun)(static_cast<void> (0));
905 LineState State = Indenter->getInitialState(FirstIndent, FirstStartColumn,
906 &Line, /*DryRun=*/false);
907 while (State.NextToken) {
908 bool Newline =
909 Indenter->mustBreak(State) ||
910 (Indenter->canBreak(State) && State.NextToken->NewlinesBefore > 0);
911 unsigned Penalty = 0;
912 formatChildren(State, Newline, /*DryRun=*/false, Penalty);
913 Indenter->addTokenToState(State, Newline, /*DryRun=*/false);
914 }
915 return 0;
916 }
917};
918
919/// Formatter that puts all tokens into a single line without breaks.
920class NoLineBreakFormatter : public LineFormatter {
921public:
922 NoLineBreakFormatter(ContinuationIndenter *Indenter,
923 WhitespaceManager *Whitespaces, const FormatStyle &Style,
924 UnwrappedLineFormatter *BlockFormatter)
925 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
926
927 /// Puts all tokens into a single line.
928 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
929 unsigned FirstStartColumn, bool DryRun) override {
930 unsigned Penalty = 0;
931 LineState State =
932 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
933 while (State.NextToken) {
934 formatChildren(State, /*NewLine=*/false, DryRun, Penalty);
935 Indenter->addTokenToState(
936 State, /*Newline=*/State.NextToken->MustBreakBefore, DryRun);
937 }
938 return Penalty;
939 }
940};
941
942/// Finds the best way to break lines.
943class OptimizingLineFormatter : public LineFormatter {
944public:
945 OptimizingLineFormatter(ContinuationIndenter *Indenter,
946 WhitespaceManager *Whitespaces,
947 const FormatStyle &Style,
948 UnwrappedLineFormatter *BlockFormatter)
949 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
950
951 /// Formats the line by finding the best line breaks with line lengths
952 /// below the column limit.
953 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
954 unsigned FirstStartColumn, bool DryRun) override {
955 LineState State =
956 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
957
958 // If the ObjC method declaration does not fit on a line, we should format
959 // it with one arg per line.
960 if (State.Line->Type == LT_ObjCMethodDecl)
961 State.Stack.back().BreakBeforeParameter = true;
962
963 // Find best solution in solution space.
964 return analyzeSolutionSpace(State, DryRun);
965 }
966
967private:
968 struct CompareLineStatePointers {
969 bool operator()(LineState *obj1, LineState *obj2) const {
970 return *obj1 < *obj2;
971 }
972 };
973
974 /// A pair of <penalty, count> that is used to prioritize the BFS on.
975 ///
976 /// In case of equal penalties, we want to prefer states that were inserted
977 /// first. During state generation we make sure that we insert states first
978 /// that break the line as late as possible.
979 typedef std::pair<unsigned, unsigned> OrderedPenalty;
980
981 /// An edge in the solution space from \c Previous->State to \c State,
982 /// inserting a newline dependent on the \c NewLine.
983 struct StateNode {
984 StateNode(const LineState &State, bool NewLine, StateNode *Previous)
985 : State(State), NewLine(NewLine), Previous(Previous) {}
986 LineState State;
987 bool NewLine;
988 StateNode *Previous;
989 };
990
991 /// An item in the prioritized BFS search queue. The \c StateNode's
992 /// \c State has the given \c OrderedPenalty.
993 typedef std::pair<OrderedPenalty, StateNode *> QueueItem;
994
995 /// The BFS queue type.
996 typedef std::priority_queue<QueueItem, std::vector<QueueItem>,
997 std::greater<QueueItem>>
998 QueueType;
999
1000 /// Analyze the entire solution space starting from \p InitialState.
1001 ///
1002 /// This implements a variant of Dijkstra's algorithm on the graph that spans
1003 /// the solution space (\c LineStates are the nodes). The algorithm tries to
1004 /// find the shortest path (the one with lowest penalty) from \p InitialState
1005 /// to a state where all tokens are placed. Returns the penalty.
1006 ///
1007 /// If \p DryRun is \c false, directly applies the changes.
1008 unsigned analyzeSolutionSpace(LineState &InitialState, bool DryRun) {
1009 std::set<LineState *, CompareLineStatePointers> Seen;
1010
1011 // Increasing count of \c StateNode items we have created. This is used to
1012 // create a deterministic order independent of the container.
1013 unsigned Count = 0;
1014 QueueType Queue;
1015
1016 // Insert start element into queue.
1017 StateNode *Node =
1018 new (Allocator.Allocate()) StateNode(InitialState, false, nullptr);
1019 Queue.push(QueueItem(OrderedPenalty(0, Count), Node));
1020 ++Count;
1021
1022 unsigned Penalty = 0;
1023
1024 // While not empty, take first element and follow edges.
1025 while (!Queue.empty()) {
1026 Penalty = Queue.top().first.first;
1027 StateNode *Node = Queue.top().second;
1028 if (!Node->State.NextToken) {
1029 LLVM_DEBUG(llvm::dbgs()do { } while (false)
1030 << "\n---\nPenalty for line: " << Penalty << "\n")do { } while (false);
1031 break;
1032 }
1033 Queue.pop();
1034
1035 // Cut off the analysis of certain solutions if the analysis gets too
1036 // complex. See description of IgnoreStackForComparison.
1037 if (Count > 50000)
1038 Node->State.IgnoreStackForComparison = true;
1039
1040 if (!Seen.insert(&Node->State).second)
1041 // State already examined with lower penalty.
1042 continue;
1043
1044 FormatDecision LastFormat = Node->State.NextToken->getDecision();
1045 if (LastFormat == FD_Unformatted || LastFormat == FD_Continue)
1046 addNextStateToQueue(Penalty, Node, /*NewLine=*/false, &Count, &Queue);
1047 if (LastFormat == FD_Unformatted || LastFormat == FD_Break)
1048 addNextStateToQueue(Penalty, Node, /*NewLine=*/true, &Count, &Queue);
1049 }
1050
1051 if (Queue.empty()) {
1052 // We were unable to find a solution, do nothing.
1053 // FIXME: Add diagnostic?
1054 LLVM_DEBUG(llvm::dbgs() << "Could not find a solution.\n")do { } while (false);
1055 return 0;
1056 }
1057
1058 // Reconstruct the solution.
1059 if (!DryRun)
1060 reconstructPath(InitialState, Queue.top().second);
1061
1062 LLVM_DEBUG(llvm::dbgs()do { } while (false)
1063 << "Total number of analyzed states: " << Count << "\n")do { } while (false);
1064 LLVM_DEBUG(llvm::dbgs() << "---\n")do { } while (false);
1065
1066 return Penalty;
1067 }
1068
1069 /// Add the following state to the analysis queue \c Queue.
1070 ///
1071 /// Assume the current state is \p PreviousNode and has been reached with a
1072 /// penalty of \p Penalty. Insert a line break if \p NewLine is \c true.
1073 void addNextStateToQueue(unsigned Penalty, StateNode *PreviousNode,
1074 bool NewLine, unsigned *Count, QueueType *Queue) {
1075 if (NewLine && !Indenter->canBreak(PreviousNode->State))
1076 return;
1077 if (!NewLine && Indenter->mustBreak(PreviousNode->State))
1078 return;
1079
1080 StateNode *Node = new (Allocator.Allocate())
1081 StateNode(PreviousNode->State, NewLine, PreviousNode);
1082 if (!formatChildren(Node->State, NewLine, /*DryRun=*/true, Penalty))
1083 return;
1084
1085 Penalty += Indenter->addTokenToState(Node->State, NewLine, true);
1086
1087 Queue->push(QueueItem(OrderedPenalty(Penalty, *Count), Node));
1088 ++(*Count);
1089 }
1090
1091 /// Applies the best formatting by reconstructing the path in the
1092 /// solution space that leads to \c Best.
1093 void reconstructPath(LineState &State, StateNode *Best) {
1094 std::deque<StateNode *> Path;
1095 // We do not need a break before the initial token.
1096 while (Best->Previous) {
1097 Path.push_front(Best);
1098 Best = Best->Previous;
1099 }
1100 for (auto I = Path.begin(), E = Path.end(); I != E; ++I) {
1101 unsigned Penalty = 0;
1102 formatChildren(State, (*I)->NewLine, /*DryRun=*/false, Penalty);
1103 Penalty += Indenter->addTokenToState(State, (*I)->NewLine, false);
Value stored to 'Penalty' is never read
1104
1105 LLVM_DEBUG({do { } while (false)
1106 printLineState((*I)->Previous->State);do { } while (false)
1107 if ((*I)->NewLine) {do { } while (false)
1108 llvm::dbgs() << "Penalty for placing "do { } while (false)
1109 << (*I)->Previous->State.NextToken->Tok.getName()do { } while (false)
1110 << " on a new line: " << Penalty << "\n";do { } while (false)
1111 }do { } while (false)
1112 })do { } while (false);
1113 }
1114 }
1115
1116 llvm::SpecificBumpPtrAllocator<StateNode> Allocator;
1117};
1118
1119} // anonymous namespace
1120
1121unsigned UnwrappedLineFormatter::format(
1122 const SmallVectorImpl<AnnotatedLine *> &Lines, bool DryRun,
1123 int AdditionalIndent, bool FixBadIndentation, unsigned FirstStartColumn,
1124 unsigned NextStartColumn, unsigned LastStartColumn) {
1125 LineJoiner Joiner(Style, Keywords, Lines);
1126
1127 // Try to look up already computed penalty in DryRun-mode.
1128 std::pair<const SmallVectorImpl<AnnotatedLine *> *, unsigned> CacheKey(
1129 &Lines, AdditionalIndent);
1130 auto CacheIt = PenaltyCache.find(CacheKey);
1131 if (DryRun && CacheIt != PenaltyCache.end())
1132 return CacheIt->second;
1133
1134 assert(!Lines.empty())(static_cast<void> (0));
1135 unsigned Penalty = 0;
1136 LevelIndentTracker IndentTracker(Style, Keywords, Lines[0]->Level,
1137 AdditionalIndent);
1138 const AnnotatedLine *PrevPrevLine = nullptr;
1139 const AnnotatedLine *PreviousLine = nullptr;
1140 const AnnotatedLine *NextLine = nullptr;
1141
1142 // The minimum level of consecutive lines that have been formatted.
1143 unsigned RangeMinLevel = UINT_MAX(2147483647 *2U +1U);
1144
1145 bool FirstLine = true;
1146 for (const AnnotatedLine *Line =
1147 Joiner.getNextMergedLine(DryRun, IndentTracker);
1148 Line; Line = NextLine, FirstLine = false) {
1149 const AnnotatedLine &TheLine = *Line;
1150 unsigned Indent = IndentTracker.getIndent();
1151
1152 // We continue formatting unchanged lines to adjust their indent, e.g. if a
1153 // scope was added. However, we need to carefully stop doing this when we
1154 // exit the scope of affected lines to prevent indenting a the entire
1155 // remaining file if it currently missing a closing brace.
1156 bool PreviousRBrace =
1157 PreviousLine && PreviousLine->startsWith(tok::r_brace);
1158 bool ContinueFormatting =
1159 TheLine.Level > RangeMinLevel ||
1160 (TheLine.Level == RangeMinLevel && !PreviousRBrace &&
1161 !TheLine.startsWith(tok::r_brace));
1162
1163 bool FixIndentation = (FixBadIndentation || ContinueFormatting) &&
1164 Indent != TheLine.First->OriginalColumn;
1165 bool ShouldFormat = TheLine.Affected || FixIndentation;
1166 // We cannot format this line; if the reason is that the line had a
1167 // parsing error, remember that.
1168 if (ShouldFormat && TheLine.Type == LT_Invalid && Status) {
1169 Status->FormatComplete = false;
1170 Status->Line =
1171 SourceMgr.getSpellingLineNumber(TheLine.First->Tok.getLocation());
1172 }
1173
1174 if (ShouldFormat && TheLine.Type != LT_Invalid) {
1175 if (!DryRun) {
1176 bool LastLine = Line->First->is(tok::eof);
1177 formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines, Indent,
1178 LastLine ? LastStartColumn : NextStartColumn + Indent);
1179 }
1180
1181 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1182 unsigned ColumnLimit = getColumnLimit(TheLine.InPPDirective, NextLine);
1183 bool FitsIntoOneLine =
1184 TheLine.Last->TotalLength + Indent <= ColumnLimit ||
1185 (TheLine.Type == LT_ImportStatement &&
1186 (Style.Language != FormatStyle::LK_JavaScript ||
1187 !Style.JavaScriptWrapImports)) ||
1188 (Style.isCSharp() &&
1189 TheLine.InPPDirective); // don't split #regions in C#
1190 if (Style.ColumnLimit == 0)
1191 NoColumnLimitLineFormatter(Indenter, Whitespaces, Style, this)
1192 .formatLine(TheLine, NextStartColumn + Indent,
1193 FirstLine ? FirstStartColumn : 0, DryRun);
1194 else if (FitsIntoOneLine)
1195 Penalty += NoLineBreakFormatter(Indenter, Whitespaces, Style, this)
1196 .formatLine(TheLine, NextStartColumn + Indent,
1197 FirstLine ? FirstStartColumn : 0, DryRun);
1198 else
1199 Penalty += OptimizingLineFormatter(Indenter, Whitespaces, Style, this)
1200 .formatLine(TheLine, NextStartColumn + Indent,
1201 FirstLine ? FirstStartColumn : 0, DryRun);
1202 RangeMinLevel = std::min(RangeMinLevel, TheLine.Level);
1203 } else {
1204 // If no token in the current line is affected, we still need to format
1205 // affected children.
1206 if (TheLine.ChildrenAffected)
1207 for (const FormatToken *Tok = TheLine.First; Tok; Tok = Tok->Next)
1208 if (!Tok->Children.empty())
1209 format(Tok->Children, DryRun);
1210
1211 // Adapt following lines on the current indent level to the same level
1212 // unless the current \c AnnotatedLine is not at the beginning of a line.
1213 bool StartsNewLine =
1214 TheLine.First->NewlinesBefore > 0 || TheLine.First->IsFirst;
1215 if (StartsNewLine)
1216 IndentTracker.adjustToUnmodifiedLine(TheLine);
1217 if (!DryRun) {
1218 bool ReformatLeadingWhitespace =
1219 StartsNewLine && ((PreviousLine && PreviousLine->Affected) ||
1220 TheLine.LeadingEmptyLinesAffected);
1221 // Format the first token.
1222 if (ReformatLeadingWhitespace)
1223 formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines,
1224 TheLine.First->OriginalColumn,
1225 TheLine.First->OriginalColumn);
1226 else
1227 Whitespaces->addUntouchableToken(*TheLine.First,
1228 TheLine.InPPDirective);
1229
1230 // Notify the WhitespaceManager about the unchanged whitespace.
1231 for (FormatToken *Tok = TheLine.First->Next; Tok; Tok = Tok->Next)
1232 Whitespaces->addUntouchableToken(*Tok, TheLine.InPPDirective);
1233 }
1234 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1235 RangeMinLevel = UINT_MAX(2147483647 *2U +1U);
1236 }
1237 if (!DryRun)
1238 markFinalized(TheLine.First);
1239 PrevPrevLine = PreviousLine;
1240 PreviousLine = &TheLine;
1241 }
1242 PenaltyCache[CacheKey] = Penalty;
1243 return Penalty;
1244}
1245
1246void UnwrappedLineFormatter::formatFirstToken(
1247 const AnnotatedLine &Line, const AnnotatedLine *PreviousLine,
1248 const AnnotatedLine *PrevPrevLine,
1249 const SmallVectorImpl<AnnotatedLine *> &Lines, unsigned Indent,
1250 unsigned NewlineIndent) {
1251 FormatToken &RootToken = *Line.First;
1252 if (RootToken.is(tok::eof)) {
1253 unsigned Newlines = std::min(RootToken.NewlinesBefore, 1u);
1254 unsigned TokenIndent = Newlines ? NewlineIndent : 0;
1255 Whitespaces->replaceWhitespace(RootToken, Newlines, TokenIndent,
1256 TokenIndent);
1257 return;
1258 }
1259 unsigned Newlines =
1260 std::min(RootToken.NewlinesBefore, Style.MaxEmptyLinesToKeep + 1);
1261 // Remove empty lines before "}" where applicable.
1262 if (RootToken.is(tok::r_brace) &&
1263 (!RootToken.Next ||
1264 (RootToken.Next->is(tok::semi) && !RootToken.Next->Next)) &&
1265 // Do not remove empty lines before namespace closing "}".
1266 !getNamespaceToken(&Line, Lines))
1267 Newlines = std::min(Newlines, 1u);
1268 // Remove empty lines at the start of nested blocks (lambdas/arrow functions)
1269 if (PreviousLine == nullptr && Line.Level > 0)
1270 Newlines = std::min(Newlines, 1u);
1271 if (Newlines == 0 && !RootToken.IsFirst)
1272 Newlines = 1;
1273 if (RootToken.IsFirst && !RootToken.HasUnescapedNewline)
1274 Newlines = 0;
1275
1276 // Remove empty lines after "{".
1277 if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine &&
1278 PreviousLine->Last->is(tok::l_brace) &&
1279 !PreviousLine->startsWithNamespace() &&
1280 !(PrevPrevLine && PrevPrevLine->startsWithNamespace() &&
1281 PreviousLine->startsWith(tok::l_brace)) &&
1282 !startsExternCBlock(*PreviousLine))
1283 Newlines = 1;
1284
1285 // Insert or remove empty line before access specifiers.
1286 if (PreviousLine && RootToken.isAccessSpecifier()) {
1287 switch (Style.EmptyLineBeforeAccessModifier) {
1288 case FormatStyle::ELBAMS_Never:
1289 if (Newlines > 1)
1290 Newlines = 1;
1291 break;
1292 case FormatStyle::ELBAMS_Leave:
1293 Newlines = std::max(RootToken.NewlinesBefore, 1u);
1294 break;
1295 case FormatStyle::ELBAMS_LogicalBlock:
1296 if (PreviousLine->Last->isOneOf(tok::semi, tok::r_brace) && Newlines <= 1)
1297 Newlines = 2;
1298 if (PreviousLine->First->isAccessSpecifier())
1299 Newlines = 1; // Previous is an access modifier remove all new lines.
1300 break;
1301 case FormatStyle::ELBAMS_Always: {
1302 const FormatToken *previousToken;
1303 if (PreviousLine->Last->is(tok::comment))
1304 previousToken = PreviousLine->Last->getPreviousNonComment();
1305 else
1306 previousToken = PreviousLine->Last;
1307 if ((!previousToken || !previousToken->is(tok::l_brace)) && Newlines <= 1)
1308 Newlines = 2;
1309 } break;
1310 }
1311 }
1312
1313 // Insert or remove empty line after access specifiers.
1314 if (PreviousLine && PreviousLine->First->isAccessSpecifier() &&
1315 (!PreviousLine->InPPDirective || !RootToken.HasUnescapedNewline)) {
1316 // EmptyLineBeforeAccessModifier is handling the case when two access
1317 // modifiers follow each other.
1318 if (!RootToken.isAccessSpecifier()) {
1319 switch (Style.EmptyLineAfterAccessModifier) {
1320 case FormatStyle::ELAAMS_Never:
1321 Newlines = 1;
1322 break;
1323 case FormatStyle::ELAAMS_Leave:
1324 Newlines = std::max(Newlines, 1u);
1325 break;
1326 case FormatStyle::ELAAMS_Always:
1327 if (RootToken.is(tok::r_brace)) // Do not add at end of class.
1328 Newlines = 1u;
1329 else
1330 Newlines = std::max(Newlines, 2u);
1331 break;
1332 }
1333 }
1334 }
1335
1336 if (Newlines)
1337 Indent = NewlineIndent;
1338
1339 // Preprocessor directives get indented before the hash only if specified
1340 if (Style.IndentPPDirectives != FormatStyle::PPDIS_BeforeHash &&
1341 (Line.Type == LT_PreprocessorDirective ||
1342 Line.Type == LT_ImportStatement))
1343 Indent = 0;
1344
1345 Whitespaces->replaceWhitespace(RootToken, Newlines, Indent, Indent,
1346 /*IsAligned=*/false,
1347 Line.InPPDirective &&
1348 !RootToken.HasUnescapedNewline);
1349}
1350
1351unsigned
1352UnwrappedLineFormatter::getColumnLimit(bool InPPDirective,
1353 const AnnotatedLine *NextLine) const {
1354 // In preprocessor directives reserve two chars for trailing " \" if the
1355 // next line continues the preprocessor directive.
1356 bool ContinuesPPDirective =
1357 InPPDirective &&
1358 // If there is no next line, this is likely a child line and the parent
1359 // continues the preprocessor directive.
1360 (!NextLine ||
1361 (NextLine->InPPDirective &&
1362 // If there is an unescaped newline between this line and the next, the
1363 // next line starts a new preprocessor directive.
1364 !NextLine->First->HasUnescapedNewline));
1365 return Style.ColumnLimit - (ContinuesPPDirective ? 2 : 0);
1366}
1367
1368} // namespace format
1369} // namespace clang