Make StringTableBuilder to cache hash values.

This change seems to speed up LLD a bit if it has a lot of mergeable
sections. The number is below. It's not too bad for a small patch.

Time to link Clang (debug build):

w/o patch 6.3696 seconds
w/patch   6.2746 seconds (-1.5%)

Differential Revision: http://reviews.llvm.org/D19933

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268698 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Rui Ueyama
2016-05-06 00:51:58 +00:00
parent 2dd0b894b1
commit ecc2a1e20c
2 changed files with 9 additions and 6 deletions
+4 -4
View File
@@ -34,11 +34,11 @@ StringTableBuilder::StringTableBuilder(Kind K, unsigned Alignment)
}
}
typedef std::pair<StringRef, size_t> StringPair;
typedef std::pair<CachedHash<StringRef>, size_t> StringPair;
// Returns the character at Pos from end of a string.
static int charTailAt(StringPair *P, size_t Pos) {
StringRef S = P->first;
StringRef S = P->first.Val;
if (Pos >= S.size())
return -1;
return (unsigned char)S[S.size() - Pos - 1];
@@ -86,7 +86,7 @@ void StringTableBuilder::finalizeInOrder() {
}
void StringTableBuilder::finalizeStringTable(bool Optimize) {
typedef std::pair<StringRef, size_t> StringOffsetPair;
typedef std::pair<CachedHash<StringRef>, size_t> StringOffsetPair;
std::vector<StringOffsetPair *> Strings;
Strings.reserve(StringIndexMap.size());
for (StringOffsetPair &P : StringIndexMap)
@@ -121,7 +121,7 @@ void StringTableBuilder::finalizeStringTable(bool Optimize) {
StringRef Previous;
for (StringOffsetPair *P : Strings) {
StringRef S = P->first;
StringRef S = P->first.Val;
if (K == WinCOFF)
assert(S.size() > COFF::NameSize && "Short string in COFF string table!");