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-rw-r--r--contrib/llvm/lib/Support/FormatVariadic.cpp156
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diff --git a/contrib/llvm/lib/Support/FormatVariadic.cpp b/contrib/llvm/lib/Support/FormatVariadic.cpp
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+//===- FormatVariadic.cpp - Format string parsing and analysis ----*-C++-*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/FormatVariadic.h"
+
+using namespace llvm;
+
+static Optional<AlignStyle> translateLocChar(char C) {
+ switch (C) {
+ case '-':
+ return AlignStyle::Left;
+ case '=':
+ return AlignStyle::Center;
+ case '+':
+ return AlignStyle::Right;
+ default:
+ return None;
+ }
+ LLVM_BUILTIN_UNREACHABLE;
+}
+
+bool formatv_object_base::consumeFieldLayout(StringRef &Spec, AlignStyle &Where,
+ size_t &Align, char &Pad) {
+ Where = AlignStyle::Right;
+ Align = 0;
+ Pad = ' ';
+ if (Spec.empty())
+ return true;
+
+ if (Spec.size() > 1) {
+ // A maximum of 2 characters at the beginning can be used for something
+ // other
+ // than the width.
+ // If Spec[1] is a loc char, then Spec[0] is a pad char and Spec[2:...]
+ // contains the width.
+ // Otherwise, if Spec[0] is a loc char, then Spec[1:...] contains the width.
+ // Otherwise, Spec[0:...] contains the width.
+ if (auto Loc = translateLocChar(Spec[1])) {
+ Pad = Spec[0];
+ Where = *Loc;
+ Spec = Spec.drop_front(2);
+ } else if (auto Loc = translateLocChar(Spec[0])) {
+ Where = *Loc;
+ Spec = Spec.drop_front(1);
+ }
+ }
+
+ bool Failed = Spec.consumeInteger(0, Align);
+ return !Failed;
+}
+
+Optional<ReplacementItem>
+formatv_object_base::parseReplacementItem(StringRef Spec) {
+ StringRef RepString = Spec.trim("{}");
+
+ // If the replacement sequence does not start with a non-negative integer,
+ // this is an error.
+ char Pad = ' ';
+ std::size_t Align = 0;
+ AlignStyle Where = AlignStyle::Right;
+ StringRef Options;
+ size_t Index = 0;
+ RepString = RepString.trim();
+ if (RepString.consumeInteger(0, Index)) {
+ assert(false && "Invalid replacement sequence index!");
+ return ReplacementItem{};
+ }
+ RepString = RepString.trim();
+ if (!RepString.empty() && RepString.front() == ',') {
+ RepString = RepString.drop_front();
+ if (!consumeFieldLayout(RepString, Where, Align, Pad))
+ assert(false && "Invalid replacement field layout specification!");
+ }
+ RepString = RepString.trim();
+ if (!RepString.empty() && RepString.front() == ':') {
+ Options = RepString.drop_front().trim();
+ RepString = StringRef();
+ }
+ RepString = RepString.trim();
+ if (!RepString.empty()) {
+ assert(false && "Unexpected characters found in replacement string!");
+ }
+
+ return ReplacementItem{Spec, Index, Align, Where, Pad, Options};
+}
+
+std::pair<ReplacementItem, StringRef>
+formatv_object_base::splitLiteralAndReplacement(StringRef Fmt) {
+ StringRef Rep;
+ StringRef Remainder;
+ std::size_t From = 0;
+ while (From < Fmt.size() && From != StringRef::npos) {
+ std::size_t BO = Fmt.find_first_of('{', From);
+ // Everything up until the first brace is a literal.
+ if (BO != 0)
+ return std::make_pair(ReplacementItem{Fmt.substr(0, BO)}, Fmt.substr(BO));
+
+ StringRef Braces =
+ Fmt.drop_front(BO).take_while([](char C) { return C == '{'; });
+ // If there is more than one brace, then some of them are escaped. Treat
+ // these as replacements.
+ if (Braces.size() > 1) {
+ size_t NumEscapedBraces = Braces.size() / 2;
+ StringRef Middle = Fmt.substr(BO, NumEscapedBraces);
+ StringRef Right = Fmt.drop_front(BO + NumEscapedBraces * 2);
+ return std::make_pair(ReplacementItem{Middle}, Right);
+ }
+ // An unterminated open brace is undefined. We treat the rest of the string
+ // as a literal replacement, but we assert to indicate that this is
+ // undefined and that we consider it an error.
+ std::size_t BC = Fmt.find_first_of('}', BO);
+ if (BC == StringRef::npos) {
+ assert(
+ false &&
+ "Unterminated brace sequence. Escape with {{ for a literal brace.");
+ return std::make_pair(ReplacementItem{Fmt}, StringRef());
+ }
+
+ // Even if there is a closing brace, if there is another open brace before
+ // this closing brace, treat this portion as literal, and try again with the
+ // next one.
+ std::size_t BO2 = Fmt.find_first_of('{', BO + 1);
+ if (BO2 < BC)
+ return std::make_pair(ReplacementItem{Fmt.substr(0, BO2)},
+ Fmt.substr(BO2));
+
+ StringRef Spec = Fmt.slice(BO + 1, BC);
+ StringRef Right = Fmt.substr(BC + 1);
+
+ auto RI = parseReplacementItem(Spec);
+ if (RI.hasValue())
+ return std::make_pair(*RI, Right);
+
+ // If there was an error parsing the replacement item, treat it as an
+ // invalid replacement spec, and just continue.
+ From = BC + 1;
+ }
+ return std::make_pair(ReplacementItem{Fmt}, StringRef());
+}
+
+std::vector<ReplacementItem>
+formatv_object_base::parseFormatString(StringRef Fmt) {
+ std::vector<ReplacementItem> Replacements;
+ ReplacementItem I;
+ while (!Fmt.empty()) {
+ std::tie(I, Fmt) = splitLiteralAndReplacement(Fmt);
+ if (I.Type != ReplacementType::Empty)
+ Replacements.push_back(I);
+ }
+ return Replacements;
+}
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