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 <algorithm>
12 
13 namespace Fortran::runtime::io {
14 
15 template <typename INT, typename UINT>
16 bool EditIntegerOutput(IoStatementState &io, const DataEdit &edit, INT n) {
17   char buffer[130], *end = &buffer[sizeof buffer], *p = end;
18   bool isNegative{false};
19   if constexpr (std::is_same_v<INT, UINT>) {
20     isNegative = (n >> (8 * sizeof(INT) - 1)) != 0;
21   } else {
22     isNegative = n < 0;
23   }
24   UINT un{static_cast<UINT>(isNegative ? -n : n)};
25   int signChars{0};
26   switch (edit.descriptor) {
27   case DataEdit::ListDirected:
28   case 'G':
29   case 'I':
30     if (isNegative || (edit.modes.editingFlags & signPlus)) {
31       signChars = 1; // '-' or '+'
32     }
33     while (un > 0) {
34       auto quotient{un / 10u};
35       *--p = '0' + static_cast<int>(un - UINT{10} * quotient);
36       un = quotient;
37     }
38     break;
39   case 'B':
40     for (; un > 0; un >>= 1) {
41       *--p = '0' + (static_cast<int>(un) & 1);
42     }
43     break;
44   case 'O':
45     for (; un > 0; un >>= 3) {
46       *--p = '0' + (static_cast<int>(un) & 7);
47     }
48     break;
49   case 'Z':
50     for (; un > 0; un >>= 4) {
51       int digit = static_cast<int>(un) & 0xf;
52       *--p = digit >= 10 ? 'A' + (digit - 10) : '0' + digit;
53     }
54     break;
55   default:
56     io.GetIoErrorHandler().Crash(
57         "Data edit descriptor '%c' may not be used with an INTEGER data item",
58         edit.descriptor);
59     return false;
60   }
61 
62   int digits = end - p;
63   int leadingZeroes{0};
64   int editWidth{edit.width.value_or(0)};
65   if (edit.digits && digits <= *edit.digits) { // Iw.m
66     if (*edit.digits == 0 && n == 0) {
67       // Iw.0 with zero value: output field must be blank.  For I0.0
68       // and a zero value, emit one blank character.
69       signChars = 0; // in case of SP
70       editWidth = std::max(1, editWidth);
71     } else {
72       leadingZeroes = *edit.digits - digits;
73     }
74   } else if (n == 0) {
75     leadingZeroes = 1;
76   }
77   int total{signChars + leadingZeroes + digits};
78   if (editWidth > 0 && total > editWidth) {
79     return io.EmitRepeated('*', editWidth);
80   }
81   int leadingSpaces{std::max(0, editWidth - total)};
82   if (edit.IsListDirected()) {
83     if (static_cast<std::size_t>(total) >
84             io.GetConnectionState().RemainingSpaceInRecord() &&
85         !io.AdvanceRecord()) {
86       return false;
87     }
88     leadingSpaces = 1;
89   }
90   return io.EmitRepeated(' ', leadingSpaces) &&
91       io.Emit(n < 0 ? "-" : "+", signChars) &&
92       io.EmitRepeated('0', leadingZeroes) && io.Emit(p, digits);
93 }
94 
95 // Formats the exponent (see table 13.1 for all the cases)
96 const char *RealOutputEditingBase::FormatExponent(
97     int expo, const DataEdit &edit, int &length) {
98   char *eEnd{&exponent_[sizeof exponent_]};
99   char *exponent{eEnd};
100   for (unsigned e{static_cast<unsigned>(std::abs(expo))}; e > 0;) {
101     unsigned quotient{e / 10u};
102     *--exponent = '0' + e - 10 * quotient;
103     e = quotient;
104   }
105   if (edit.expoDigits) {
106     if (int ed{*edit.expoDigits}) { // Ew.dEe with e > 0
107       while (exponent > exponent_ + 2 /*E+*/ && exponent + ed > eEnd) {
108         *--exponent = '0';
109       }
110     } else if (exponent == eEnd) {
111       *--exponent = '0'; // Ew.dE0 with zero-valued exponent
112     }
113   } else { // ensure at least two exponent digits
114     while (exponent + 2 > eEnd) {
115       *--exponent = '0';
116     }
117   }
118   *--exponent = expo < 0 ? '-' : '+';
119   if (edit.expoDigits || exponent + 3 == eEnd) {
120     *--exponent = edit.descriptor == 'D' ? 'D' : 'E'; // not 'G'
121   }
122   length = eEnd - exponent;
123   return exponent;
124 }
125 
126 bool RealOutputEditingBase::EmitPrefix(
127     const DataEdit &edit, std::size_t length, std::size_t width) {
128   if (edit.IsListDirected()) {
129     int prefixLength{edit.descriptor == DataEdit::ListDirectedRealPart ? 2
130             : edit.descriptor == DataEdit::ListDirectedImaginaryPart   ? 0
131                                                                        : 1};
132     int suffixLength{edit.descriptor == DataEdit::ListDirectedRealPart ||
133                 edit.descriptor == DataEdit::ListDirectedImaginaryPart
134             ? 1
135             : 0};
136     length += prefixLength + suffixLength;
137     ConnectionState &connection{io_.GetConnectionState()};
138     return (connection.positionInRecord == 0 ||
139                length <= connection.RemainingSpaceInRecord() ||
140                io_.AdvanceRecord()) &&
141         io_.Emit(" (", prefixLength);
142   } else if (width > length) {
143     return io_.EmitRepeated(' ', width - length);
144   } else {
145     return true;
146   }
147 }
148 
149 bool RealOutputEditingBase::EmitSuffix(const DataEdit &edit) {
150   if (edit.descriptor == DataEdit::ListDirectedRealPart) {
151     return io_.Emit(edit.modes.editingFlags & decimalComma ? ";" : ",", 1);
152   } else if (edit.descriptor == DataEdit::ListDirectedImaginaryPart) {
153     return io_.Emit(")", 1);
154   } else {
155     return true;
156   }
157 }
158 
159 template <int binaryPrecision>
160 decimal::ConversionToDecimalResult RealOutputEditing<binaryPrecision>::Convert(
161     int significantDigits, const DataEdit &edit, int flags) {
162   if (edit.modes.editingFlags & signPlus) {
163     flags |= decimal::AlwaysSign;
164   }
165   auto converted{decimal::ConvertToDecimal<binaryPrecision>(buffer_,
166       sizeof buffer_, static_cast<enum decimal::DecimalConversionFlags>(flags),
167       significantDigits, edit.modes.round, x_)};
168   if (!converted.str) { // overflow
169     io_.GetIoErrorHandler().Crash(
170         "RealOutputEditing::Convert : buffer size %zd was insufficient",
171         sizeof buffer_);
172   }
173   return converted;
174 }
175 
176 // 13.7.2.3.3 in F'2018
177 template <int binaryPrecision>
178 bool RealOutputEditing<binaryPrecision>::EditEorDOutput(const DataEdit &edit) {
179   int editDigits{edit.digits.value_or(0)}; // 'd' field
180   int editWidth{edit.width.value_or(0)}; // 'w' field
181   int significantDigits{editDigits};
182   int flags{0};
183   if (editWidth == 0) { // "the processor selects the field width"
184     if (edit.digits.has_value()) { // E0.d
185       editWidth = editDigits + 6; // -.666E+ee
186     } else { // E0
187       flags |= decimal::Minimize;
188       significantDigits =
189           sizeof buffer_ - 5; // sign, NUL, + 3 extra for EN scaling
190     }
191   }
192   bool isEN{edit.variation == 'N'};
193   bool isES{edit.variation == 'S'};
194   int scale{isEN || isES ? 1 : edit.modes.scale}; // 'kP' value
195   int zeroesAfterPoint{0};
196   if (scale < 0) {
197     zeroesAfterPoint = -scale;
198     significantDigits = std::max(0, significantDigits - zeroesAfterPoint);
199   } else if (scale > 0) {
200     ++significantDigits;
201     scale = std::min(scale, significantDigits + 1);
202   }
203   // In EN editing, multiple attempts may be necessary, so it's in a loop.
204   while (true) {
205     decimal::ConversionToDecimalResult converted{
206         Convert(significantDigits, edit, flags)};
207     if (IsInfOrNaN(converted)) {
208       return EmitPrefix(edit, converted.length, editWidth) &&
209           io_.Emit(converted.str, converted.length) && EmitSuffix(edit);
210     }
211     if (!IsZero()) {
212       converted.decimalExponent -= scale;
213     }
214     if (isEN && scale < 3 && (converted.decimalExponent % 3) != 0) {
215       // EN mode: boost the scale and significant digits, try again; need
216       // an effective exponent field that's a multiple of three.
217       ++scale;
218       ++significantDigits;
219       continue;
220     }
221     // Format the exponent (see table 13.1 for all the cases)
222     int expoLength{0};
223     const char *exponent{
224         FormatExponent(converted.decimalExponent, edit, expoLength)};
225     int signLength{*converted.str == '-' || *converted.str == '+' ? 1 : 0};
226     int convertedDigits{static_cast<int>(converted.length) - signLength};
227     int zeroesBeforePoint{std::max(0, scale - convertedDigits)};
228     int digitsBeforePoint{std::max(0, scale - zeroesBeforePoint)};
229     int digitsAfterPoint{convertedDigits - digitsBeforePoint};
230     int trailingZeroes{flags & decimal::Minimize
231             ? 0
232             : std::max(0,
233                   significantDigits - (convertedDigits + zeroesBeforePoint))};
234     int totalLength{signLength + digitsBeforePoint + zeroesBeforePoint +
235         1 /*'.'*/ + zeroesAfterPoint + digitsAfterPoint + trailingZeroes +
236         expoLength};
237     int width{editWidth > 0 ? editWidth : totalLength};
238     if (totalLength > width) {
239       return io_.EmitRepeated('*', width);
240     }
241     if (totalLength < width && digitsBeforePoint == 0 &&
242         zeroesBeforePoint == 0) {
243       zeroesBeforePoint = 1;
244       ++totalLength;
245     }
246     return EmitPrefix(edit, totalLength, width) &&
247         io_.Emit(converted.str, signLength + digitsBeforePoint) &&
248         io_.EmitRepeated('0', zeroesBeforePoint) &&
249         io_.Emit(edit.modes.editingFlags & decimalComma ? "," : ".", 1) &&
250         io_.EmitRepeated('0', zeroesAfterPoint) &&
251         io_.Emit(
252             converted.str + signLength + digitsBeforePoint, digitsAfterPoint) &&
253         io_.EmitRepeated('0', trailingZeroes) &&
254         io_.Emit(exponent, expoLength) && EmitSuffix(edit);
255   }
256 }
257 
258 // 13.7.2.3.2 in F'2018
259 template <int binaryPrecision>
260 bool RealOutputEditing<binaryPrecision>::EditFOutput(const DataEdit &edit) {
261   int fracDigits{edit.digits.value_or(0)}; // 'd' field
262   const int editWidth{edit.width.value_or(0)}; // 'w' field
263   int flags{0};
264   if (editWidth == 0) { // "the processor selects the field width"
265     if (!edit.digits.has_value()) { // F0
266       flags |= decimal::Minimize;
267       fracDigits = sizeof buffer_ - 2; // sign & NUL
268     }
269   }
270   // Multiple conversions may be needed to get the right number of
271   // effective rounded fractional digits.
272   int extraDigits{0};
273   while (true) {
274     decimal::ConversionToDecimalResult converted{
275         Convert(extraDigits + fracDigits, edit, flags)};
276     if (IsInfOrNaN(converted)) {
277       return EmitPrefix(edit, converted.length, editWidth) &&
278           io_.Emit(converted.str, converted.length) && EmitSuffix(edit);
279     }
280     int scale{IsZero() ? 1 : edit.modes.scale}; // kP
281     int expo{converted.decimalExponent + scale};
282     if (expo > extraDigits && extraDigits >= 0) {
283       extraDigits = expo;
284       if (!edit.digits.has_value()) { // F0
285         fracDigits = sizeof buffer_ - extraDigits - 2; // sign & NUL
286       }
287       continue;
288     } else if (expo < extraDigits && extraDigits > -fracDigits) {
289       extraDigits = std::max(expo, -fracDigits);
290       continue;
291     }
292     int signLength{*converted.str == '-' || *converted.str == '+' ? 1 : 0};
293     int convertedDigits{static_cast<int>(converted.length) - signLength};
294     int digitsBeforePoint{std::max(0, std::min(expo, convertedDigits))};
295     int zeroesBeforePoint{std::max(0, expo - digitsBeforePoint)};
296     int zeroesAfterPoint{std::min(fracDigits, std::max(0, -expo))};
297     int digitsAfterPoint{convertedDigits - digitsBeforePoint};
298     int trailingZeroes{flags & decimal::Minimize
299             ? 0
300             : std::max(0, fracDigits - (zeroesAfterPoint + digitsAfterPoint))};
301     if (digitsBeforePoint + zeroesBeforePoint + zeroesAfterPoint +
302             digitsAfterPoint + trailingZeroes ==
303         0) {
304       zeroesBeforePoint = 1; // "." -> "0."
305     }
306     int totalLength{signLength + digitsBeforePoint + zeroesBeforePoint +
307         1 /*'.'*/ + zeroesAfterPoint + digitsAfterPoint + trailingZeroes};
308     int width{editWidth > 0 ? editWidth : totalLength};
309     if (totalLength > width) {
310       return io_.EmitRepeated('*', width);
311     }
312     if (totalLength < width && digitsBeforePoint + zeroesBeforePoint == 0) {
313       zeroesBeforePoint = 1;
314       ++totalLength;
315     }
316     return EmitPrefix(edit, totalLength, width) &&
317         io_.Emit(converted.str, signLength + digitsBeforePoint) &&
318         io_.EmitRepeated('0', zeroesBeforePoint) &&
319         io_.Emit(edit.modes.editingFlags & decimalComma ? "," : ".", 1) &&
320         io_.EmitRepeated('0', zeroesAfterPoint) &&
321         io_.Emit(
322             converted.str + signLength + digitsBeforePoint, digitsAfterPoint) &&
323         io_.EmitRepeated('0', trailingZeroes) &&
324         io_.EmitRepeated(' ', trailingBlanks_) && EmitSuffix(edit);
325   }
326 }
327 
328 // 13.7.5.2.3 in F'2018
329 template <int binaryPrecision>
330 DataEdit RealOutputEditing<binaryPrecision>::EditForGOutput(DataEdit edit) {
331   edit.descriptor = 'E';
332   int significantDigits{
333       edit.digits.value_or(BinaryFloatingPoint::decimalPrecision)}; // 'd'
334   if (!edit.width.has_value() || (*edit.width > 0 && significantDigits == 0)) {
335     return edit; // Gw.0 -> Ew.0 for w > 0
336   }
337   decimal::ConversionToDecimalResult converted{
338       Convert(significantDigits, edit)};
339   if (IsInfOrNaN(converted)) {
340     return edit;
341   }
342   int expo{IsZero() ? 1 : converted.decimalExponent}; // 's'
343   if (expo < 0 || expo > significantDigits) {
344     return edit; // Ew.d
345   }
346   edit.descriptor = 'F';
347   edit.modes.scale = 0; // kP is ignored for G when no exponent field
348   trailingBlanks_ = 0;
349   int editWidth{edit.width.value_or(0)};
350   if (editWidth > 0) {
351     int expoDigits{edit.expoDigits.value_or(0)};
352     trailingBlanks_ = expoDigits > 0 ? expoDigits + 2 : 4; // 'n'
353     *edit.width = std::max(0, editWidth - trailingBlanks_);
354   }
355   if (edit.digits.has_value()) {
356     *edit.digits = std::max(0, *edit.digits - expo);
357   }
358   return edit;
359 }
360 
361 // 13.10.4 in F'2018
362 template <int binaryPrecision>
363 bool RealOutputEditing<binaryPrecision>::EditListDirectedOutput(
364     const DataEdit &edit) {
365   decimal::ConversionToDecimalResult converted{Convert(1, edit)};
366   if (IsInfOrNaN(converted)) {
367     return EditEorDOutput(edit);
368   }
369   int expo{converted.decimalExponent};
370   if (expo < 0 || expo > BinaryFloatingPoint::decimalPrecision) {
371     DataEdit copy{edit};
372     copy.modes.scale = 1; // 1P
373     return EditEorDOutput(copy);
374   }
375   return EditFOutput(edit);
376 }
377 
378 // 13.7.5.2.6 in F'2018
379 template <int binaryPrecision>
380 bool RealOutputEditing<binaryPrecision>::EditEXOutput(const DataEdit &) {
381   io_.GetIoErrorHandler().Crash(
382       "EX output editing is not yet implemented"); // TODO
383 }
384 
385 template <int binaryPrecision>
386 bool RealOutputEditing<binaryPrecision>::Edit(const DataEdit &edit) {
387   switch (edit.descriptor) {
388   case 'D':
389     return EditEorDOutput(edit);
390   case 'E':
391     if (edit.variation == 'X') {
392       return EditEXOutput(edit);
393     } else {
394       return EditEorDOutput(edit);
395     }
396   case 'F':
397     return EditFOutput(edit);
398   case 'B':
399   case 'O':
400   case 'Z':
401     return EditIntegerOutput(io_, edit,
402         decimal::BinaryFloatingPointNumber<binaryPrecision>{x_}.raw());
403   case 'G':
404     return Edit(EditForGOutput(edit));
405   default:
406     if (edit.IsListDirected()) {
407       return EditListDirectedOutput(edit);
408     }
409     io_.GetIoErrorHandler().SignalError(IostatErrorInFormat,
410         "Data edit descriptor '%c' may not be used with a REAL data item",
411         edit.descriptor);
412     return false;
413   }
414   return false;
415 }
416 
417 bool ListDirectedLogicalOutput(IoStatementState &io,
418     ListDirectedStatementState<Direction::Output> &list, bool truth) {
419   return list.EmitLeadingSpaceOrAdvance(io, 1) && io.Emit(truth ? "T" : "F", 1);
420 }
421 
422 bool EditLogicalOutput(IoStatementState &io, const DataEdit &edit, bool truth) {
423   switch (edit.descriptor) {
424   case 'L':
425   case 'G':
426     return io.EmitRepeated(' ', std::max(0, edit.width.value_or(1) - 1)) &&
427         io.Emit(truth ? "T" : "F", 1);
428   default:
429     io.GetIoErrorHandler().SignalError(IostatErrorInFormat,
430         "Data edit descriptor '%c' may not be used with a LOGICAL data item",
431         edit.descriptor);
432     return false;
433   }
434 }
435 
436 bool ListDirectedDefaultCharacterOutput(IoStatementState &io,
437     ListDirectedStatementState<Direction::Output> &list, const char *x,
438     std::size_t length) {
439   bool ok{list.EmitLeadingSpaceOrAdvance(io, length, true)};
440   MutableModes &modes{io.mutableModes()};
441   ConnectionState &connection{io.GetConnectionState()};
442   if (modes.delim) {
443     // Value is delimited with ' or " marks, and interior
444     // instances of that character are doubled.  When split
445     // over multiple lines, delimit each lines' part.
446     ok &= io.Emit(&modes.delim, 1);
447     for (std::size_t j{0}; j < length; ++j) {
448       if (list.NeedAdvance(connection, 2)) {
449         ok &= io.Emit(&modes.delim, 1) && io.AdvanceRecord() &&
450             io.Emit(&modes.delim, 1);
451       }
452       if (x[j] == modes.delim) {
453         ok &= io.EmitRepeated(modes.delim, 2);
454       } else {
455         ok &= io.Emit(&x[j], 1);
456       }
457     }
458     ok &= io.Emit(&modes.delim, 1);
459   } else {
460     // Undelimited list-directed output
461     std::size_t put{0};
462     while (put < length) {
463       auto chunk{std::min(length - put, connection.RemainingSpaceInRecord())};
464       ok &= io.Emit(x + put, chunk);
465       put += chunk;
466       if (put < length) {
467         ok &= io.AdvanceRecord() && io.Emit(" ", 1);
468       }
469     }
470     list.lastWasUndelimitedCharacter = true;
471   }
472   return ok;
473 }
474 
475 bool EditDefaultCharacterOutput(IoStatementState &io, const DataEdit &edit,
476     const char *x, std::size_t length) {
477   switch (edit.descriptor) {
478   case 'A':
479   case 'G':
480     break;
481   default:
482     io.GetIoErrorHandler().SignalError(IostatErrorInFormat,
483         "Data edit descriptor '%c' may not be used with a CHARACTER data item",
484         edit.descriptor);
485     return false;
486   }
487   int len{static_cast<int>(length)};
488   int width{edit.width.value_or(len)};
489   return io.EmitRepeated(' ', std::max(0, width - len)) &&
490       io.Emit(x, std::min(width, len));
491 }
492 
493 template bool EditIntegerOutput<std::int64_t, std::uint64_t>(
494     IoStatementState &, const DataEdit &, std::int64_t);
495 template bool EditIntegerOutput<common::uint128_t, common::uint128_t>(
496     IoStatementState &, const DataEdit &, common::uint128_t);
497 
498 template class RealOutputEditing<2>;
499 template class RealOutputEditing<3>;
500 template class RealOutputEditing<4>;
501 template class RealOutputEditing<8>;
502 template class RealOutputEditing<10>;
503 // TODO: double/double
504 template class RealOutputEditing<16>;
505 } // namespace Fortran::runtime::io
506