xref: /llvm-project/flang/runtime/edit-output.cpp (revision 231fae90874bae6f224dcf5cd613218bc450731a) 
1 //===-- runtime/edit-output.cpp ---------------------------------*- C++ -*-===//
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 "edit-output.h"
10 #include "flang/Common/uint128.h"
11 #include "flang/Common/unsigned-const-division.h"
12 #include <algorithm>
13 
14 namespace Fortran::runtime::io {
15 
16 template<typename INT, typename UINT>
17 bool EditIntegerOutput(IoStatementState &io, const DataEdit &edit, INT n) {
18   char buffer[130], *end = &buffer[sizeof buffer], *p = end;
19   bool isNegative{false};
20   if constexpr (std::is_same_v<INT, UINT>) {
21     isNegative = (n >> (8 * sizeof(INT) - 1)) != 0;
22   } else {
23     isNegative = n < 0;
24   }
25   UINT un{static_cast<UINT>(isNegative ? -n : n)};
26   int signChars{0};
27   switch (edit.descriptor) {
28   case DataEdit::ListDirected:
29   case 'G':
30   case 'I':
31     if (isNegative || (edit.modes.editingFlags & signPlus)) {
32       signChars = 1;  // '-' or '+'
33     }
34     while (un > 0) {
35       auto quotient{common::DivideUnsignedBy<UINT, 10>(un)};
36       *--p = '0' + static_cast<int>(un - UINT{10} * quotient);
37       un = quotient;
38     }
39     break;
40   case 'B':
41     for (; un > 0; un >>= 1) {
42       *--p = '0' + (static_cast<int>(un) & 1);
43     }
44     break;
45   case 'O':
46     for (; un > 0; un >>= 3) {
47       *--p = '0' + (static_cast<int>(un) & 7);
48     }
49     break;
50   case 'Z':
51     for (; un > 0; un >>= 4) {
52       int digit = static_cast<int>(un) & 0xf;
53       *--p = digit >= 10 ? 'A' + (digit - 10) : '0' + digit;
54     }
55     break;
56   default:
57     io.GetIoErrorHandler().Crash(
58         "Data edit descriptor '%c' may not be used with an INTEGER data item",
59         edit.descriptor);
60     return false;
61   }
62 
63   int digits = end - p;
64   int leadingZeroes{0};
65   int editWidth{edit.width.value_or(0)};
66   if (edit.digits && digits <= *edit.digits) {  // Iw.m
67     if (*edit.digits == 0 && n == 0) {
68       // Iw.0 with zero value: output field must be blank.  For I0.0
69       // and a zero value, emit one blank character.
70       signChars = 0;  // in case of SP
71       editWidth = std::max(1, editWidth);
72     } else {
73       leadingZeroes = *edit.digits - digits;
74     }
75   } else if (n == 0) {
76     leadingZeroes = 1;
77   }
78   int total{signChars + leadingZeroes + digits};
79   if (editWidth > 0 && total > editWidth) {
80     return io.EmitRepeated('*', editWidth);
81   }
82   int leadingSpaces{std::max(0, editWidth - total)};
83   if (edit.IsListDirected()) {
84     if (static_cast<std::size_t>(total) >
85             io.GetConnectionState().RemainingSpaceInRecord() &&
86         !io.AdvanceRecord()) {
87       return false;
88     }
89     leadingSpaces = 1;
90   }
91   return io.EmitRepeated(' ', leadingSpaces) &&
92       io.Emit(n < 0 ? "-" : "+", signChars) &&
93       io.EmitRepeated('0', leadingZeroes) && io.Emit(p, digits);
94 }
95 
96 // Formats the exponent (see table 13.1 for all the cases)
97 const char *RealOutputEditingBase::FormatExponent(
98     int expo, const DataEdit &edit, int &length) {
99   char *eEnd{&exponent_[sizeof exponent_]};
100   char *exponent{eEnd};
101   for (unsigned e{static_cast<unsigned>(std::abs(expo))}; e > 0;) {
102     unsigned quotient{common::DivideUnsignedBy<unsigned, 10>(e)};
103     *--exponent = '0' + e - 10 * quotient;
104     e = quotient;
105   }
106   if (edit.expoDigits) {
107     if (int ed{*edit.expoDigits}) {  // Ew.dEe with e > 0
108       while (exponent > exponent_ + 2 /*E+*/ && exponent + ed > eEnd) {
109         *--exponent = '0';
110       }
111     } else if (exponent == eEnd) {
112       *--exponent = '0';  // Ew.dE0 with zero-valued exponent
113     }
114   } else {  // ensure at least two exponent digits
115     while (exponent + 2 > eEnd) {
116       *--exponent = '0';
117     }
118   }
119   *--exponent = expo < 0 ? '-' : '+';
120   if (edit.expoDigits || exponent + 3 == eEnd) {
121     *--exponent = edit.descriptor == 'D' ? 'D' : 'E';  // not 'G'
122   }
123   length = eEnd - exponent;
124   return exponent;
125 }
126 
127 bool RealOutputEditingBase::EmitPrefix(
128     const DataEdit &edit, std::size_t length, std::size_t width) {
129   if (edit.IsListDirected()) {
130     int prefixLength{edit.descriptor == DataEdit::ListDirectedRealPart
131             ? 2
132             : edit.descriptor == DataEdit::ListDirectedImaginaryPart ? 0 : 1};
133     int suffixLength{edit.descriptor == DataEdit::ListDirectedRealPart ||
134                 edit.descriptor == DataEdit::ListDirectedImaginaryPart
135             ? 1
136             : 0};
137     length += prefixLength + suffixLength;
138     ConnectionState &connection{io_.GetConnectionState()};
139     return (connection.positionInRecord == 0 ||
140                length <= connection.RemainingSpaceInRecord() ||
141                io_.AdvanceRecord()) &&
142         io_.Emit(" (", prefixLength);
143   } else if (width > length) {
144     return io_.EmitRepeated(' ', width - length);
145   } else {
146     return true;
147   }
148 }
149 
150 bool RealOutputEditingBase::EmitSuffix(const DataEdit &edit) {
151   if (edit.descriptor == DataEdit::ListDirectedRealPart) {
152     return io_.Emit(edit.modes.editingFlags & decimalComma ? ";" : ",", 1);
153   } else if (edit.descriptor == DataEdit::ListDirectedImaginaryPart) {
154     return io_.Emit(")", 1);
155   } else {
156     return true;
157   }
158 }
159 
160 template<int binaryPrecision>
161 decimal::ConversionToDecimalResult RealOutputEditing<binaryPrecision>::Convert(
162     int significantDigits, const DataEdit &edit, int flags) {
163   if (edit.modes.editingFlags & signPlus) {
164     flags |= decimal::AlwaysSign;
165   }
166   auto converted{decimal::ConvertToDecimal<binaryPrecision>(buffer_,
167       sizeof buffer_, static_cast<enum decimal::DecimalConversionFlags>(flags),
168       significantDigits, edit.modes.round, x_)};
169   if (!converted.str) {  // overflow
170     io_.GetIoErrorHandler().Crash(
171         "RealOutputEditing::Convert : buffer size %zd was insufficient",
172         sizeof buffer_);
173   }
174   return converted;
175 }
176 
177 // 13.7.2.3.3 in F'2018
178 template<int binaryPrecision>
179 bool RealOutputEditing<binaryPrecision>::EditEorDOutput(const DataEdit &edit) {
180   int editDigits{edit.digits.value_or(0)};  // 'd' field
181   int editWidth{edit.width.value_or(0)};  // 'w' field
182   int significantDigits{editDigits};
183   int flags{0};
184   if (editWidth == 0) {  // "the processor selects the field width"
185     if (edit.digits.has_value()) {  // E0.d
186       editWidth = editDigits + 6;  // -.666E+ee
187     } else {  // E0
188       flags |= decimal::Minimize;
189       significantDigits =
190           sizeof buffer_ - 5;  // sign, NUL, + 3 extra for EN scaling
191     }
192   }
193   bool isEN{edit.variation == 'N'};
194   bool isES{edit.variation == 'S'};
195   int scale{isEN || isES ? 1 : edit.modes.scale};  // 'kP' value
196   int zeroesAfterPoint{0};
197   if (scale < 0) {
198     zeroesAfterPoint = -scale;
199     significantDigits = std::max(0, significantDigits - zeroesAfterPoint);
200   } else if (scale > 0) {
201     ++significantDigits;
202     scale = std::min(scale, significantDigits + 1);
203   }
204   // In EN editing, multiple attempts may be necessary, so it's in a loop.
205   while (true) {
206     decimal::ConversionToDecimalResult converted{
207         Convert(significantDigits, edit, flags)};
208     if (converted.length > 0 && !IsDecimalNumber(converted.str)) {  // Inf, NaN
209       return EmitPrefix(edit, converted.length, editWidth) &&
210           io_.Emit(converted.str, converted.length) && EmitSuffix(edit);
211     }
212     if (!IsZero()) {
213       converted.decimalExponent -= scale;
214     }
215     if (isEN && scale < 3 && (converted.decimalExponent % 3) != 0) {
216       // EN mode: boost the scale and significant digits, try again; need
217       // an effective exponent field that's a multiple of three.
218       ++scale;
219       ++significantDigits;
220       continue;
221     }
222     // Format the exponent (see table 13.1 for all the cases)
223     int expoLength{0};
224     const char *exponent{
225         FormatExponent(converted.decimalExponent, edit, expoLength)};
226     int signLength{*converted.str == '-' || *converted.str == '+' ? 1 : 0};
227     int convertedDigits{static_cast<int>(converted.length) - signLength};
228     int zeroesBeforePoint{std::max(0, scale - convertedDigits)};
229     int digitsBeforePoint{std::max(0, scale - zeroesBeforePoint)};
230     int digitsAfterPoint{convertedDigits - digitsBeforePoint};
231     int trailingZeroes{flags & decimal::Minimize
232             ? 0
233             : std::max(0,
234                   significantDigits - (convertedDigits + zeroesBeforePoint))};
235     int totalLength{signLength + digitsBeforePoint + zeroesBeforePoint +
236         1 /*'.'*/ + zeroesAfterPoint + digitsAfterPoint + trailingZeroes +
237         expoLength};
238     int width{editWidth > 0 ? editWidth : totalLength};
239     if (totalLength > width) {
240       return io_.EmitRepeated('*', width);
241     }
242     if (totalLength < width && digitsBeforePoint == 0 &&
243         zeroesBeforePoint == 0) {
244       zeroesBeforePoint = 1;
245       ++totalLength;
246     }
247     return EmitPrefix(edit, totalLength, width) &&
248         io_.Emit(converted.str, signLength + digitsBeforePoint) &&
249         io_.EmitRepeated('0', zeroesBeforePoint) &&
250         io_.Emit(edit.modes.editingFlags & decimalComma ? "," : ".", 1) &&
251         io_.EmitRepeated('0', zeroesAfterPoint) &&
252         io_.Emit(
253             converted.str + signLength + digitsBeforePoint, digitsAfterPoint) &&
254         io_.EmitRepeated('0', trailingZeroes) &&
255         io_.Emit(exponent, expoLength) && EmitSuffix(edit);
256   }
257 }
258 
259 // 13.7.2.3.2 in F'2018
260 template<int binaryPrecision>
261 bool RealOutputEditing<binaryPrecision>::EditFOutput(const DataEdit &edit) {
262   int fracDigits{edit.digits.value_or(0)};  // 'd' field
263   int extraDigits{0};
264   int editWidth{edit.width.value_or(0)};  // 'w' field
265   int flags{0};
266   if (editWidth == 0) {  // "the processor selects the field width"
267     if (!edit.digits.has_value()) {  // F0
268       flags |= decimal::Minimize;
269       fracDigits = sizeof buffer_ - 2;  // sign & NUL
270     }
271   }
272   // Multiple conversions may be needed to get the right number of
273   // effective rounded fractional digits.
274   while (true) {
275     decimal::ConversionToDecimalResult converted{
276         Convert(extraDigits + fracDigits, edit, flags)};
277     if (converted.length > 0 && !IsDecimalNumber(converted.str)) {  // Inf, NaN
278       return EmitPrefix(edit, converted.length, editWidth) &&
279           io_.Emit(converted.str, converted.length) && EmitSuffix(edit);
280     }
281     int scale{IsZero() ? -1 : edit.modes.scale};
282     int expo{converted.decimalExponent - scale};
283     if (expo > extraDigits) {
284       extraDigits = expo;
285       if (flags & decimal::Minimize) {
286         fracDigits = sizeof buffer_ - extraDigits - 2;  // sign & NUL
287       }
288       continue;  // try again
289     }
290     int signLength{*converted.str == '-' || *converted.str == '+' ? 1 : 0};
291     int convertedDigits{static_cast<int>(converted.length) - signLength};
292     int digitsBeforePoint{std::max(0, std::min(expo, convertedDigits))};
293     int zeroesBeforePoint{std::max(0, expo - digitsBeforePoint)};
294     int zeroesAfterPoint{std::max(0, -expo)};
295     int digitsAfterPoint{convertedDigits - digitsBeforePoint};
296     int trailingZeroes{flags & decimal::Minimize
297             ? 0
298             : std::max(0, fracDigits - (zeroesAfterPoint + digitsAfterPoint))};
299     if (digitsBeforePoint + zeroesBeforePoint + zeroesAfterPoint +
300             digitsAfterPoint + trailingZeroes ==
301         0) {
302       ++zeroesBeforePoint;  // "." -> "0."
303     }
304     int totalLength{signLength + digitsBeforePoint + zeroesBeforePoint +
305         1 /*'.'*/ + zeroesAfterPoint + digitsAfterPoint + trailingZeroes};
306     int width{editWidth > 0 ? editWidth : totalLength};
307     if (totalLength > width) {
308       return io_.EmitRepeated('*', width);
309     }
310     if (totalLength < width && digitsBeforePoint + zeroesBeforePoint == 0) {
311       zeroesBeforePoint = 1;
312       ++totalLength;
313     }
314     return EmitPrefix(edit, totalLength, width) &&
315         io_.Emit(converted.str, signLength + digitsBeforePoint) &&
316         io_.EmitRepeated('0', zeroesBeforePoint) &&
317         io_.Emit(edit.modes.editingFlags & decimalComma ? "," : ".", 1) &&
318         io_.EmitRepeated('0', zeroesAfterPoint) &&
319         io_.Emit(
320             converted.str + signLength + digitsBeforePoint, digitsAfterPoint) &&
321         io_.EmitRepeated('0', trailingZeroes) &&
322         io_.EmitRepeated(' ', trailingBlanks_) && EmitSuffix(edit);
323   }
324 }
325 
326 // 13.7.5.2.3 in F'2018
327 template<int binaryPrecision>
328 DataEdit RealOutputEditing<binaryPrecision>::EditForGOutput(DataEdit edit) {
329   edit.descriptor = 'E';
330   if (!edit.width.has_value() ||
331       (*edit.width > 0 && edit.digits.value_or(-1) == 0)) {
332     return edit;  // Gw.0 -> Ew.0 for w > 0
333   }
334   decimal::ConversionToDecimalResult converted{Convert(1, edit)};
335   if (!IsDecimalNumber(converted.str)) {  // Inf, NaN
336     return edit;
337   }
338   int expo{IsZero() ? 1 : converted.decimalExponent};  // 's'
339   int significantDigits{
340       edit.digits.value_or(BinaryFloatingPoint::decimalPrecision)};  // 'd'
341   if (expo < 0 || expo > significantDigits) {
342     return edit;  // Ew.d
343   }
344   edit.descriptor = 'F';
345   edit.modes.scale = 0;  // kP is ignored for G when no exponent field
346   trailingBlanks_ = 0;
347   int editWidth{edit.width.value_or(0)};
348   if (editWidth > 0) {
349     int expoDigits{edit.expoDigits.value_or(0)};
350     trailingBlanks_ = expoDigits > 0 ? expoDigits + 2 : 4;  // 'n'
351     *edit.width = std::max(0, editWidth - trailingBlanks_);
352   }
353   if (edit.digits.has_value()) {
354     *edit.digits = std::max(0, *edit.digits - expo);
355   }
356   return edit;
357 }
358 
359 // 13.10.4 in F'2018
360 template<int binaryPrecision>
361 bool RealOutputEditing<binaryPrecision>::EditListDirectedOutput(
362     const DataEdit &edit) {
363   decimal::ConversionToDecimalResult converted{Convert(1, edit)};
364   if (!IsDecimalNumber(converted.str)) {  // Inf, NaN
365     return EditEorDOutput(edit);
366   }
367   int expo{converted.decimalExponent};
368   if (expo < 0 || expo > BinaryFloatingPoint::decimalPrecision) {
369     DataEdit copy{edit};
370     copy.modes.scale = 1;  // 1P
371     return EditEorDOutput(copy);
372   }
373   return EditFOutput(edit);
374 }
375 
376 // 13.7.5.2.6 in F'2018
377 template<int binaryPrecision>
378 bool RealOutputEditing<binaryPrecision>::EditEXOutput(const DataEdit &) {
379   io_.GetIoErrorHandler().Crash(
380       "EX output editing is not yet implemented");  // TODO
381 }
382 
383 template<int binaryPrecision>
384 bool RealOutputEditing<binaryPrecision>::Edit(const DataEdit &edit) {
385   switch (edit.descriptor) {
386   case 'D': return EditEorDOutput(edit);
387   case 'E':
388     if (edit.variation == 'X') {
389       return EditEXOutput(edit);
390     } else {
391       return EditEorDOutput(edit);
392     }
393   case 'F': return EditFOutput(edit);
394   case 'B':
395   case 'O':
396   case 'Z':
397     return EditIntegerOutput(
398         io_, edit, decimal::BinaryFloatingPointNumber<binaryPrecision>{x_}.raw);
399   case 'G': return Edit(EditForGOutput(edit));
400   default:
401     if (edit.IsListDirected()) {
402       return EditListDirectedOutput(edit);
403     }
404     io_.GetIoErrorHandler().SignalError(IostatErrorInFormat,
405         "Data edit descriptor '%c' may not be used with a REAL data item",
406         edit.descriptor);
407     return false;
408   }
409   return false;
410 }
411 
412 bool ListDirectedLogicalOutput(IoStatementState &io,
413     ListDirectedStatementState<Direction::Output> &list, bool truth) {
414   return list.EmitLeadingSpaceOrAdvance(io, 1) && io.Emit(truth ? "T" : "F", 1);
415 }
416 
417 bool EditLogicalOutput(IoStatementState &io, const DataEdit &edit, bool truth) {
418   switch (edit.descriptor) {
419   case 'L':
420   case 'G': return io.Emit(truth ? "T" : "F", 1);
421   default:
422     io.GetIoErrorHandler().SignalError(IostatErrorInFormat,
423         "Data edit descriptor '%c' may not be used with a LOGICAL data item",
424         edit.descriptor);
425     return false;
426   }
427 }
428 
429 bool ListDirectedDefaultCharacterOutput(IoStatementState &io,
430     ListDirectedStatementState<Direction::Output> &list, const char *x,
431     std::size_t length) {
432   bool ok{list.EmitLeadingSpaceOrAdvance(io, length, true)};
433   MutableModes &modes{io.mutableModes()};
434   ConnectionState &connection{io.GetConnectionState()};
435   if (modes.delim) {
436     // Value is delimited with ' or " marks, and interior
437     // instances of that character are doubled.  When split
438     // over multiple lines, delimit each lines' part.
439     ok &= io.Emit(&modes.delim, 1);
440     for (std::size_t j{0}; j < length; ++j) {
441       if (list.NeedAdvance(connection, 2)) {
442         ok &= io.Emit(&modes.delim, 1) && io.AdvanceRecord() &&
443             io.Emit(&modes.delim, 1);
444       }
445       if (x[j] == modes.delim) {
446         ok &= io.EmitRepeated(modes.delim, 2);
447       } else {
448         ok &= io.Emit(&x[j], 1);
449       }
450     }
451     ok &= io.Emit(&modes.delim, 1);
452   } else {
453     // Undelimited list-directed output
454     std::size_t put{0};
455     while (put < length) {
456       auto chunk{std::min(length - put, connection.RemainingSpaceInRecord())};
457       ok &= io.Emit(x + put, chunk);
458       put += chunk;
459       if (put < length) {
460         ok &= io.AdvanceRecord() && io.Emit(" ", 1);
461       }
462     }
463     list.lastWasUndelimitedCharacter = true;
464   }
465   return ok;
466 }
467 
468 bool EditDefaultCharacterOutput(IoStatementState &io, const DataEdit &edit,
469     const char *x, std::size_t length) {
470   switch (edit.descriptor) {
471   case 'A':
472   case 'G': break;
473   default:
474     io.GetIoErrorHandler().SignalError(IostatErrorInFormat,
475         "Data edit descriptor '%c' may not be used with a CHARACTER data item",
476         edit.descriptor);
477     return false;
478   }
479   int len{static_cast<int>(length)};
480   int width{edit.width.value_or(len)};
481   return io.EmitRepeated(' ', std::max(0, width - len)) &&
482       io.Emit(x, std::min(width, len));
483 }
484 
485 template bool EditIntegerOutput<std::int64_t, std::uint64_t>(
486     IoStatementState &, const DataEdit &, std::int64_t);
487 template bool EditIntegerOutput<common::uint128_t, common::uint128_t>(
488     IoStatementState &, const DataEdit &, common::uint128_t);
489 
490 template class RealOutputEditing<8>;
491 template class RealOutputEditing<11>;
492 template class RealOutputEditing<24>;
493 template class RealOutputEditing<53>;
494 template class RealOutputEditing<64>;
495 template class RealOutputEditing<113>;
496 }
497