Remove Node::maxVersion

This commit is contained in:
2024-02-23 17:27:19 -08:00
parent 921005edb3
commit adaa652d0d

View File

@@ -161,7 +161,6 @@ struct Node {
Node *parent = nullptr;
// The max write version over all keys that start with the search path up to
// this point
int64_t maxVersion;
Entry entry;
int16_t numChildren = 0;
bool entryPresent = false;
@@ -314,27 +313,7 @@ int64_t getChildMaxVersion(Node *self, uint8_t index) {
}
// Precondition - an entry for index must exist in the node
void setParentsChildMaxVersion(Node *self) {
int index = self->parentsIndex;
self = self->parent;
if (self == nullptr) {
return;
}
if (self->type <= Type::Node16) {
auto *self16 = static_cast<Node16 *>(self);
int i = getNodeIndex(self16, index);
self16->children[i].childMaxVersion = self16->children[i].child->maxVersion;
} else if (self->type == Type::Node48) {
auto *self48 = static_cast<Node48 *>(self);
assert(self48->bitSet.test(index));
self48->children[self48->index[index]].childMaxVersion =
self48->children[self48->index[index]].child->maxVersion;
} else {
auto *self256 = static_cast<Node256 *>(self);
self256->children[index].childMaxVersion =
self256->children[index].child->maxVersion;
}
}
int64_t &maxVersion(Node *n, ConflictSet::Impl *);
Node *getChild(Node *self, uint8_t index) {
if (self->type <= Type::Node16) {
@@ -875,13 +854,13 @@ std::string getSearchPathPrintable(Node *n);
// point or range version according to cmp, but this version short circuits as
// soon as it can prove that there's no conflict.
bool checkPointRead(Node *n, const std::span<const uint8_t> key,
int64_t readVersion) {
int64_t readVersion, ConflictSet::Impl *impl) {
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "Check point read: %s\n", printable(key).c_str());
#endif
auto remaining = key;
for (;;) {
if (n->maxVersion <= readVersion) {
if (maxVersion(n, impl) <= readVersion) {
return true;
}
if (remaining.size() == 0) {
@@ -1040,13 +1019,14 @@ Vector<uint8_t> getSearchPath(Arena &arena, Node *n) {
// Return true if the max version among all keys that start with key + [child],
// where begin < child < end, is <= readVersion
bool checkRangeStartsWith(Node *n, std::span<const uint8_t> key, int begin,
int end, int64_t readVersion) {
int end, int64_t readVersion,
ConflictSet::Impl *impl) {
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "%s(%02x,%02x)*\n", printable(key).c_str(), begin, end);
#endif
auto remaining = key;
for (;;) {
if (n->maxVersion <= readVersion) {
if (maxVersion(n, impl) <= readVersion) {
return true;
}
if (remaining.size() == 0) {
@@ -1090,7 +1070,7 @@ bool checkRangeStartsWith(Node *n, std::span<const uint8_t> key, int begin,
if (n->entryPresent && n->entry.rangeVersion > readVersion) {
return false;
}
return n->maxVersion <= readVersion;
return maxVersion(n, impl) <= readVersion;
}
return true;
}
@@ -1114,8 +1094,9 @@ downLeftSpine:
// that are >= key is <= readVersion
struct CheckRangeLeftSide {
CheckRangeLeftSide(Node *n, std::span<const uint8_t> key, int prefixLen,
int64_t readVersion)
: n(n), remaining(key), prefixLen(prefixLen), readVersion(readVersion) {
int64_t readVersion, ConflictSet::Impl *impl)
: n(n), remaining(key), prefixLen(prefixLen), readVersion(readVersion),
impl(impl) {
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "Check range left side from %s for keys starting with %s\n",
printable(key).c_str(),
@@ -1127,6 +1108,7 @@ struct CheckRangeLeftSide {
std::span<const uint8_t> remaining;
int prefixLen;
int64_t readVersion;
ConflictSet::Impl *impl;
int searchPathLen = 0;
bool ok;
@@ -1135,13 +1117,13 @@ struct CheckRangeLeftSide {
bool step() {
switch (phase) {
case Search: {
if (n->maxVersion <= readVersion) {
if (maxVersion(n, impl) <= readVersion) {
ok = true;
return true;
}
if (remaining.size() == 0) {
assert(searchPathLen >= prefixLen);
ok = n->maxVersion <= readVersion;
ok = maxVersion(n, impl) <= readVersion;
return true;
}
@@ -1161,7 +1143,7 @@ struct CheckRangeLeftSide {
return downLeftSpine();
}
n = getChildExists(n, c);
ok = n->maxVersion <= readVersion;
ok = maxVersion(n, impl) <= readVersion;
return true;
} else {
n = nextSibling(n);
@@ -1188,7 +1170,7 @@ struct CheckRangeLeftSide {
ok = false;
return true;
}
ok = n->maxVersion <= readVersion;
ok = maxVersion(n, impl) <= readVersion;
return true;
} else {
n = nextSibling(n);
@@ -1207,7 +1189,7 @@ struct CheckRangeLeftSide {
ok = false;
return true;
}
ok = n->maxVersion <= readVersion;
ok = maxVersion(n, impl) <= readVersion;
return true;
}
}
@@ -1240,9 +1222,9 @@ struct CheckRangeLeftSide {
// that are < key is <= readVersion
struct CheckRangeRightSide {
CheckRangeRightSide(Node *n, std::span<const uint8_t> key, int prefixLen,
int64_t readVersion)
int64_t readVersion, ConflictSet::Impl *impl)
: n(n), key(key), remaining(key), prefixLen(prefixLen),
readVersion(readVersion) {
readVersion(readVersion), impl(impl) {
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "Check range right side to %s for keys starting with %s\n",
printable(key).c_str(),
@@ -1255,6 +1237,7 @@ struct CheckRangeRightSide {
std::span<const uint8_t> remaining;
int prefixLen;
int64_t readVersion;
ConflictSet::Impl *impl;
int searchPathLen = 0;
bool ok;
@@ -1353,7 +1336,7 @@ struct CheckRangeRightSide {
bool backtrack() {
for (;;) {
if (searchPathLen > prefixLen && n->maxVersion > readVersion) {
if (searchPathLen > prefixLen && maxVersion(n, impl) > readVersion) {
ok = false;
return true;
}
@@ -1385,12 +1368,13 @@ struct CheckRangeRightSide {
};
bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
std::span<const uint8_t> end, int64_t readVersion) {
std::span<const uint8_t> end, int64_t readVersion,
ConflictSet::Impl *impl) {
int lcp = longestCommonPrefix(begin.data(), end.data(),
std::min(begin.size(), end.size()));
if (lcp == int(begin.size()) && end.size() == begin.size() + 1 &&
end.back() == 0) {
return checkPointRead(n, begin, readVersion);
return checkPointRead(n, begin, readVersion, impl);
}
SearchStepWise search{n, begin.subspan(0, lcp)};
@@ -1399,7 +1383,7 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
assert(getSearchPath(arena, search.n) <=>
begin.subspan(0, lcp - search.remaining.size()) ==
0);
if (search.n->maxVersion <= readVersion) {
if (maxVersion(search.n, impl) <= readVersion) {
return true;
}
if (search.step()) {
@@ -1419,19 +1403,19 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
lcp -= consumed;
if (lcp == int(begin.size())) {
CheckRangeRightSide checkRangeRightSide{n, end, lcp, readVersion};
CheckRangeRightSide checkRangeRightSide{n, end, lcp, readVersion, impl};
while (!checkRangeRightSide.step())
;
return checkRangeRightSide.ok;
}
if (!checkRangeStartsWith(n, begin.subspan(0, lcp), begin[lcp], end[lcp],
readVersion)) {
readVersion, impl)) {
return false;
}
CheckRangeLeftSide checkRangeLeftSide{n, begin, lcp + 1, readVersion};
CheckRangeRightSide checkRangeRightSide{n, end, lcp + 1, readVersion};
CheckRangeLeftSide checkRangeLeftSide{n, begin, lcp + 1, readVersion, impl};
CheckRangeRightSide checkRangeRightSide{n, end, lcp + 1, readVersion, impl};
for (;;) {
bool leftDone = checkRangeLeftSide.step();
@@ -1462,7 +1446,8 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
// `maxVersion` at least `writeVersion` as a postcondition.
template <bool kBegin>
[[nodiscard]] Node *insert(Node **self, std::span<const uint8_t> key,
int64_t writeVersion, NodeAllocators *allocators) {
int64_t writeVersion, NodeAllocators *allocators,
ConflictSet::Impl *impl) {
for (;;) {
@@ -1473,6 +1458,7 @@ template <bool kBegin>
(*self)->partialKey, key.data(), commonLen);
if (partialKeyIndex < (*self)->partialKeyLen) {
auto *old = *self;
int64_t oldMaxVersion = maxVersion(old, impl);
*self = allocators->node4.allocate();
@@ -1485,7 +1471,7 @@ template <bool kBegin>
old;
old->parent = *self;
old->parentsIndex = old->partialKey[partialKeyIndex];
setParentsChildMaxVersion(old);
maxVersion(old, impl) = oldMaxVersion;
memmove(old->partialKey, old->partialKey + partialKeyIndex + 1,
old->partialKeyLen - (partialKeyIndex + 1));
@@ -1505,8 +1491,8 @@ template <bool kBegin>
}
if constexpr (kBegin) {
(*self)->maxVersion = std::max((*self)->maxVersion, writeVersion);
setParentsChildMaxVersion(*self);
auto &m = maxVersion(*self, impl);
m = std::max(m, writeVersion);
}
if (key.size() == 0) {
@@ -1514,8 +1500,8 @@ template <bool kBegin>
}
if constexpr (!kBegin) {
(*self)->maxVersion = std::max((*self)->maxVersion, writeVersion);
setParentsChildMaxVersion(*self);
auto &m = maxVersion(*self, impl);
m = std::max(m, writeVersion);
}
auto &child = getOrCreateChild(*self, key.front(), allocators);
@@ -1523,9 +1509,8 @@ template <bool kBegin>
child = allocators->node4.allocate();
child->parent = *self;
child->parentsIndex = key.front();
child->maxVersion =
maxVersion(child, impl) =
kBegin ? writeVersion : std::numeric_limits<int64_t>::lowest();
setParentsChildMaxVersion(child);
}
self = &child;
@@ -1553,14 +1538,13 @@ void destroyTree(Node *root) {
void addPointWrite(Node *&root, int64_t oldestVersion,
std::span<const uint8_t> key, int64_t writeVersion,
NodeAllocators *allocators) {
auto *n = insert<true>(&root, key, writeVersion, allocators);
NodeAllocators *allocators, ConflictSet::Impl *impl) {
auto *n = insert<true>(&root, key, writeVersion, allocators, impl);
if (!n->entryPresent) {
auto *p = nextLogical(n);
n->entryPresent = true;
n->entry.pointVersion = writeVersion;
n->maxVersion = writeVersion;
setParentsChildMaxVersion(n);
maxVersion(n, impl) = writeVersion;
n->entry.rangeVersion =
p != nullptr ? p->entry.rangeVersion : oldestVersion;
} else {
@@ -1570,13 +1554,15 @@ void addPointWrite(Node *&root, int64_t oldestVersion,
void addWriteRange(Node *&root, int64_t oldestVersion,
std::span<const uint8_t> begin, std::span<const uint8_t> end,
int64_t writeVersion, NodeAllocators *allocators) {
int64_t writeVersion, NodeAllocators *allocators,
ConflictSet::Impl *impl) {
int lcp = longestCommonPrefix(begin.data(), end.data(),
std::min(begin.size(), end.size()));
if (lcp == int(begin.size()) && end.size() == begin.size() + 1 &&
end.back() == 0) {
return addPointWrite(root, oldestVersion, begin, writeVersion, allocators);
return addPointWrite(root, oldestVersion, begin, writeVersion, allocators,
impl);
}
auto remaining = begin.subspan(0, lcp);
@@ -1597,8 +1583,8 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
break;
}
n->maxVersion = std::max(n->maxVersion, writeVersion);
setParentsChildMaxVersion(n);
auto &m = maxVersion(n, impl);
m = std::max(m, writeVersion);
remaining = remaining.subspan(n->partialKeyLen + 1,
remaining.size() - (n->partialKeyLen + 1));
@@ -1614,7 +1600,8 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
begin = begin.subspan(consumed, begin.size() - consumed);
end = end.subspan(consumed, end.size() - consumed);
auto *beginNode = insert<true>(useAsRoot, begin, writeVersion, allocators);
auto *beginNode =
insert<true>(useAsRoot, begin, writeVersion, allocators, impl);
const bool insertedBegin = !std::exchange(beginNode->entryPresent, true);
@@ -1623,14 +1610,14 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
beginNode->entry.rangeVersion =
p != nullptr ? p->entry.rangeVersion : oldestVersion;
beginNode->entry.pointVersion = writeVersion;
beginNode->maxVersion = writeVersion;
maxVersion(beginNode, impl) = writeVersion;
}
beginNode->maxVersion = std::max(beginNode->maxVersion, writeVersion);
setParentsChildMaxVersion(beginNode);
auto &m = maxVersion(beginNode, impl);
m = std::max(m, writeVersion);
beginNode->entry.pointVersion =
std::max(beginNode->entry.pointVersion, writeVersion);
auto *endNode = insert<false>(useAsRoot, end, writeVersion, allocators);
auto *endNode = insert<false>(useAsRoot, end, writeVersion, allocators, impl);
const bool insertedEnd = !std::exchange(endNode->entryPresent, true);
@@ -1638,15 +1625,14 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
auto *p = nextLogical(endNode);
endNode->entry.pointVersion =
p != nullptr ? p->entry.rangeVersion : oldestVersion;
endNode->maxVersion =
std::max(endNode->maxVersion, endNode->entry.pointVersion);
setParentsChildMaxVersion(endNode);
auto &m = maxVersion(endNode, impl);
m = std::max(m, endNode->entry.pointVersion);
}
endNode->entry.rangeVersion = writeVersion;
if (insertedEnd) {
// beginNode may have been invalidated
beginNode = insert<true>(useAsRoot, begin, writeVersion, allocators);
beginNode = insert<true>(useAsRoot, begin, writeVersion, allocators, impl);
}
for (beginNode = nextLogical(beginNode); beginNode != endNode;) {
@@ -1771,7 +1757,7 @@ Iterator firstGeq(Node *n, std::string_view key) {
struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
void check(const ReadRange *reads, Result *result, int count) const {
void check(const ReadRange *reads, Result *result, int count) {
for (int i = 0; i < count; ++i) {
const auto &r = reads[i];
auto begin = std::span<const uint8_t>(r.begin.p, r.begin.len);
@@ -1779,8 +1765,8 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
result[i] =
reads[i].readVersion < oldestVersion ? TooOld
: (end.size() > 0
? checkRangeRead(root, begin, end, reads[i].readVersion)
: checkPointRead(root, begin, reads[i].readVersion))
? checkRangeRead(root, begin, end, reads[i].readVersion, this)
: checkPointRead(root, begin, reads[i].readVersion, this))
? Commit
: Conflict;
}
@@ -1794,10 +1780,11 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
if (w.end.len > 0) {
keyUpdates += 2;
addWriteRange(root, oldestVersion, begin, end, w.writeVersion,
&allocators);
&allocators, this);
} else {
keyUpdates += 1;
addPointWrite(root, oldestVersion, begin, w.writeVersion, &allocators);
addPointWrite(root, oldestVersion, begin, w.writeVersion, &allocators,
this);
}
}
}
@@ -1840,7 +1827,7 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
explicit Impl(int64_t oldestVersion) : oldestVersion(oldestVersion) {
// Insert ""
root = allocators.node4.allocate();
root->maxVersion = oldestVersion;
rootMaxVersion = oldestVersion;
root->entry.pointVersion = oldestVersion;
root->entry.rangeVersion = oldestVersion;
root->entryPresent = true;
@@ -1854,9 +1841,31 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
int64_t keyUpdates = 0;
Node *root;
int64_t rootMaxVersion;
int64_t oldestVersion;
};
// Precondition - an entry for index must exist in the node
int64_t &maxVersion(Node *n, ConflictSet::Impl *impl) {
int index = n->parentsIndex;
n = n->parent;
if (n == nullptr) {
return impl->rootMaxVersion;
}
if (n->type <= Type::Node16) {
auto *n16 = static_cast<Node16 *>(n);
int i = getNodeIndex(n16, index);
return n16->children[i].childMaxVersion;
} else if (n->type == Type::Node48) {
auto *n48 = static_cast<Node48 *>(n);
assert(n48->bitSet.test(index));
return n48->children[n48->index[index]].childMaxVersion;
} else {
auto *n256 = static_cast<Node256 *>(n);
return n256->children[index].childMaxVersion;
}
}
// ==================== END IMPLEMENTATION ====================
// GCOVR_EXCL_START
@@ -1988,13 +1997,15 @@ std::string getSearchPath(Node *n) {
return std::string((const char *)result.data(), result.size());
}
[[maybe_unused]] void debugPrintDot(FILE *file, Node *node) {
[[maybe_unused]] void debugPrintDot(FILE *file, Node *node,
ConflictSet::Impl *impl) {
constexpr int kSeparation = 3;
struct DebugDotPrinter {
explicit DebugDotPrinter(FILE *file) : file(file) {}
explicit DebugDotPrinter(FILE *file, ConflictSet::Impl *impl)
: file(file), impl(impl) {}
void print(Node *n, int y = 0) {
assert(n != nullptr);
@@ -2002,12 +2013,12 @@ std::string getSearchPath(Node *n) {
fprintf(file,
" k_%p [label=\"m=%" PRId64 " p=%" PRId64 " r=%" PRId64
"\n%s\", pos=\"%d,%d!\"];\n",
(void *)n, n->maxVersion, n->entry.pointVersion,
(void *)n, maxVersion(n, impl), n->entry.pointVersion,
n->entry.rangeVersion, getPartialKeyPrintable(n).c_str(), x, y);
} else {
fprintf(file, " k_%p [label=\"m=%" PRId64 "\n%s\", pos=\"%d,%d!\"];\n",
(void *)n, n->maxVersion, getPartialKeyPrintable(n).c_str(), x,
y);
(void *)n, maxVersion(n, impl),
getPartialKeyPrintable(n).c_str(), x, y);
}
x += kSeparation;
for (int child = getChildGeq(n, 0); child >= 0;
@@ -2019,12 +2030,13 @@ std::string getSearchPath(Node *n) {
}
int x = 0;
FILE *file;
ConflictSet::Impl *impl;
};
fprintf(file, "digraph ConflictSet {\n");
fprintf(file, " node [shape = box];\n");
assert(node != nullptr);
DebugDotPrinter printer{file};
DebugDotPrinter printer{file, impl};
printer.print(node);
fprintf(file, "}\n");
}
@@ -2043,15 +2055,16 @@ void checkParentPointers(Node *node, bool &success) {
}
[[maybe_unused]] int64_t checkMaxVersion(Node *root, Node *node,
int64_t oldestVersion, bool &success) {
int64_t oldestVersion, bool &success,
ConflictSet::Impl *impl) {
int64_t expected = std::numeric_limits<int64_t>::lowest();
if (node->entryPresent) {
expected = std::max(expected, node->entry.pointVersion);
}
for (int i = getChildGeq(node, 0); i >= 0; i = getChildGeq(node, i + 1)) {
auto *child = getChildExists(node, i);
expected = std::max(expected,
checkMaxVersion(root, child, oldestVersion, success));
expected = std::max(
expected, checkMaxVersion(root, child, oldestVersion, success, impl));
if (child->entryPresent) {
expected = std::max(expected, child->entry.rangeVersion);
}
@@ -2067,17 +2080,19 @@ void checkParentPointers(Node *node, bool &success) {
}
if (node->parent != nullptr &&
getChildMaxVersion(node->parent, node->parentsIndex) !=
node->maxVersion) {
maxVersion(node, impl)) {
fprintf(stderr,
"%s has max version %" PRId64
" . But parent has child max version %" PRId64 "\n",
getSearchPathPrintable(node).c_str(), node->maxVersion,
getSearchPathPrintable(node).c_str(), maxVersion(node, impl),
getChildMaxVersion(node->parent, node->parentsIndex));
success = false;
}
if (node->maxVersion > oldestVersion && node->maxVersion != expected) {
if (maxVersion(node, impl) > oldestVersion &&
maxVersion(node, impl) != expected) {
fprintf(stderr, "%s has max version %" PRId64 " . Expected %" PRId64 "\n",
getSearchPathPrintable(node).c_str(), node->maxVersion, expected);
getSearchPathPrintable(node).c_str(), maxVersion(node, impl),
expected);
success = false;
}
return expected;
@@ -2099,11 +2114,12 @@ void checkParentPointers(Node *node, bool &success) {
return total;
}
bool checkCorrectness(Node *node, int64_t oldestVersion) {
bool checkCorrectness(Node *node, int64_t oldestVersion,
ConflictSet::Impl *impl) {
bool success = true;
checkParentPointers(node, success);
checkMaxVersion(node, node, oldestVersion, success);
checkMaxVersion(node, node, oldestVersion, success, impl);
checkEntriesExist(node, success);
return success;
@@ -2134,7 +2150,7 @@ void printTree() {
write[i].writeVersion = ++writeVersion;
}
cs.addWrites(write, kNumKeys);
debugPrintDot(stdout, cs.root);
debugPrintDot(stdout, cs.root, &cs);
}
int main(void) {
@@ -2151,16 +2167,17 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
for (;;) {
bool done = driver.next();
if (!driver.ok) {
debugPrintDot(stdout, driver.cs.root);
debugPrintDot(stdout, driver.cs.root, &driver.cs);
fflush(stdout);
abort();
}
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "Check correctness\n");
#endif
bool success = checkCorrectness(driver.cs.root, driver.cs.oldestVersion);
bool success =
checkCorrectness(driver.cs.root, driver.cs.oldestVersion, &driver.cs);
if (!success) {
debugPrintDot(stdout, driver.cs.root);
debugPrintDot(stdout, driver.cs.root, &driver.cs);
fflush(stdout);
abort();
}