OptEmitter.cpp revision 360784 
1//===- OptEmitter.cpp - Helper for emitting options.----------- -----------===//
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 "OptEmitter.h"
10#include "llvm/ADT/Twine.h"
11#include "llvm/TableGen/Error.h"
12#include "llvm/TableGen/Record.h"
13#include <cctype>
14#include <cstring>
15
16namespace llvm {
17
18// Ordering on Info. The logic should match with the consumer-side function in
19// llvm/Option/OptTable.h.
20// FIXME: Make this take StringRefs instead of null terminated strings to
21// simplify callers.
22static int StrCmpOptionName(const char *A, const char *B) {
23  const char *X = A, *Y = B;
24  char a = tolower(*A), b = tolower(*B);
25  while (a == b) {
26    if (a == '\0')
27      return strcmp(A, B);
28
29    a = tolower(*++X);
30    b = tolower(*++Y);
31  }
32
33  if (a == '\0') // A is a prefix of B.
34    return 1;
35  if (b == '\0') // B is a prefix of A.
36    return -1;
37
38  // Otherwise lexicographic.
39  return (a < b) ? -1 : 1;
40}
41
42int CompareOptionRecords(Record *const *Av, Record *const *Bv) {
43  const Record *A = *Av;
44  const Record *B = *Bv;
45
46  // Sentinel options precede all others and are only ordered by precedence.
47  bool ASent = A->getValueAsDef("Kind")->getValueAsBit("Sentinel");
48  bool BSent = B->getValueAsDef("Kind")->getValueAsBit("Sentinel");
49  if (ASent != BSent)
50    return ASent ? -1 : 1;
51
52  // Compare options by name, unless they are sentinels.
53  if (!ASent)
54    if (int Cmp = StrCmpOptionName(A->getValueAsString("Name").str().c_str(),
55                                   B->getValueAsString("Name").str().c_str()))
56      return Cmp;
57
58  if (!ASent) {
59    std::vector<StringRef> APrefixes = A->getValueAsListOfStrings("Prefixes");
60    std::vector<StringRef> BPrefixes = B->getValueAsListOfStrings("Prefixes");
61
62    for (std::vector<StringRef>::const_iterator APre = APrefixes.begin(),
63                                                AEPre = APrefixes.end(),
64                                                BPre = BPrefixes.begin(),
65                                                BEPre = BPrefixes.end();
66         APre != AEPre && BPre != BEPre; ++APre, ++BPre) {
67      if (int Cmp = StrCmpOptionName(APre->str().c_str(), BPre->str().c_str()))
68        return Cmp;
69    }
70  }
71
72  // Then by the kind precedence;
73  int APrec = A->getValueAsDef("Kind")->getValueAsInt("Precedence");
74  int BPrec = B->getValueAsDef("Kind")->getValueAsInt("Precedence");
75  if (APrec == BPrec && A->getValueAsListOfStrings("Prefixes") ==
76                            B->getValueAsListOfStrings("Prefixes")) {
77    PrintError(A->getLoc(), Twine("Option is equivalent to"));
78    PrintError(B->getLoc(), Twine("Other defined here"));
79    PrintFatalError("Equivalent Options found.");
80  }
81  return APrec < BPrec ? -1 : 1;
82}
83
84} // namespace llvm
85