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[NFC][TableGen] Code cleanup in StringMatcher #141118

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Merged
merged 1 commit into from
May 22, 2025
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[NFC][TableGen] Code cleanup in StringMatcher #141118

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12 changes: 6 additions & 6 deletions llvm/include/llvm/TableGen/StringMatcher.h
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Original file line number Diff line number Diff line change
Expand Up @@ -13,10 +13,10 @@
#ifndef LLVM_TABLEGEN_STRINGMATCHER_H
#define LLVM_TABLEGEN_STRINGMATCHER_H

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/StringRef.h"
#include <string>
#include <utility>
#include <vector>

namespace llvm {

Expand All @@ -33,18 +33,18 @@ class StringMatcher {

private:
StringRef StrVariableName;
const std::vector<StringPair> &Matches;
ArrayRef<StringPair> Matches;
raw_ostream &OS;

public:
StringMatcher(StringRef strVariableName,
const std::vector<StringPair> &matches, raw_ostream &os)
: StrVariableName(strVariableName), Matches(matches), OS(os) {}
StringMatcher(StringRef StrVariableName, ArrayRef<StringPair> Matches,
raw_ostream &OS)
: StrVariableName(StrVariableName), Matches(Matches), OS(OS) {}

void Emit(unsigned Indent = 0, bool IgnoreDuplicates = false) const;

private:
bool EmitStringMatcherForChar(const std::vector<const StringPair *> &Matches,
bool EmitStringMatcherForChar(ArrayRef<const StringPair *> Matches,
unsigned CharNo, unsigned IndentCount,
bool IgnoreDuplicates) const;
};
Expand Down
33 changes: 15 additions & 18 deletions llvm/lib/TableGen/StringMatcher.cpp
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Expand Up @@ -26,16 +26,13 @@ using namespace llvm;
/// string pairs that is not shared across the whole set of strings. All
/// strings are assumed to have the same length.
static unsigned
FindFirstNonCommonLetter(const std::vector<const
StringMatcher::StringPair*> &Matches) {
FindFirstNonCommonLetter(ArrayRef<const StringMatcher::StringPair *> Matches) {
assert(!Matches.empty());
for (unsigned i = 0, e = Matches[0]->first.size(); i != e; ++i) {
// Check to see if letter i is the same across the set.
char Letter = Matches[0]->first[i];

for (auto [Idx, Letter] : enumerate(Matches[0]->first)) {
// Check to see if `Letter` is the same across the set.
for (const StringMatcher::StringPair *Match : Matches)
if (Match->first[i] != Letter)
return i;
if (Match->first[Idx] != Letter)
return Idx;
}

return Matches[0]->first.size();
Expand All @@ -47,8 +44,8 @@ FindFirstNonCommonLetter(const std::vector<const
///
/// \return - True if control can leave the emitted code fragment.
bool StringMatcher::EmitStringMatcherForChar(
const std::vector<const StringPair *> &Matches, unsigned CharNo,
unsigned IndentCount, bool IgnoreDuplicates) const {
ArrayRef<const StringPair *> Matches, unsigned CharNo, unsigned IndentCount,
bool IgnoreDuplicates) const {
assert(!Matches.empty() && "Must have at least one string to match!");
std::string Indent(IndentCount * 2 + 4, ' ');

Expand Down Expand Up @@ -110,14 +107,14 @@ bool StringMatcher::EmitStringMatcherForChar(
OS << Indent << "switch (" << StrVariableName << "[" << CharNo << "]) {\n";
OS << Indent << "default: break;\n";

for (const auto &LI : MatchesByLetter) {
for (const auto &[Letter, Matches] : MatchesByLetter) {
// TODO: escape hard stuff (like \n) if we ever care about it.
OS << Indent << "case '" << LI.first << "':\t // " << LI.second.size()
OS << Indent << "case '" << Letter << "':\t // " << Matches.size()
<< " string";
if (LI.second.size() != 1)
if (Matches.size() != 1)
OS << 's';
OS << " to match.\n";
if (EmitStringMatcherForChar(LI.second, CharNo + 1, IndentCount + 1,
if (EmitStringMatcherForChar(Matches, CharNo + 1, IndentCount + 1,
IgnoreDuplicates))
OS << Indent << " break;\n";
}
Expand All @@ -143,11 +140,11 @@ void StringMatcher::Emit(unsigned Indent, bool IgnoreDuplicates) const {
OS.indent(Indent*2+2) << "switch (" << StrVariableName << ".size()) {\n";
OS.indent(Indent*2+2) << "default: break;\n";

for (const auto &LI : MatchesByLength) {
for (const auto &[Length, Matches] : MatchesByLength) {
OS.indent(Indent * 2 + 2)
<< "case " << LI.first << ":\t // " << LI.second.size() << " string"
<< (LI.second.size() == 1 ? "" : "s") << " to match.\n";
if (EmitStringMatcherForChar(LI.second, 0, Indent, IgnoreDuplicates))
<< "case " << Length << ":\t // " << Matches.size() << " string"
<< (Matches.size() == 1 ? "" : "s") << " to match.\n";
if (EmitStringMatcherForChar(Matches, 0, Indent, IgnoreDuplicates))
OS.indent(Indent*2+4) << "break;\n";
}

Expand Down