weaselab/conflict-set
2
0
Fork 0
Code Issues 4 Packages Releases 13 Activity

CheckRangeLeftSide struct

Browse Source
This commit is contained in:
Andrew Noyes
2024-02-20 11:04:12 -08:00
parent 79987a2f55
commit 33390af817
1 changed files with 113 additions and 74 deletions
Download Patch File Download Diff File Expand all files Collapse all files

187
ConflictSet.cpp
View File

@@ -950,99 +950,135 @@ downLeftSpine:
// Return true if the max version among all keys that start with key[:prefixLen]
// that are >= key is <= readVersion
bool checkRangeLeftSide(Node *n, std::span<const uint8_t> key, int prefixLen,
int64_t 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) {
#if DEBUG_VERBOSE && !defined(NDEBUG)
fprintf(stderr, "Check range left side from %s for keys starting with %s\n",
printable(key).c_str(), printable(key.subspan(0, prefixLen)).c_str());
fprintf(stderr, "Check range left side from %s for keys starting with %s\n",
printable(key).c_str(),
printable(key.subspan(0, prefixLen)).c_str());
#endif
auto remaining = key;
}
Node *n;
std::span<const uint8_t> remaining;
int prefixLen;
int64_t readVersion;
int searchPathLen = 0;
for (;;) {
if (n->maxVersion <= readVersion) {
return true;
}
if (remaining.size() == 0) {
assert(searchPathLen >= prefixLen);
return n->maxVersion <= readVersion;
}
bool ok;
if (searchPathLen >= prefixLen) {
if (maxBetweenExclusive(n, remaining[0], 256) > readVersion) {
return false;
enum Phase { Search, DownLeftSpine } phase = Search;
bool step() {
switch (phase) {
case Search: {
if (n->maxVersion <= readVersion) {
ok = true;
return true;
}
if (remaining.size() == 0) {
assert(searchPathLen >= prefixLen);
ok = n->maxVersion <= readVersion;
return true;
}
}
int c = getChildGeq(n, remaining[0]);
if (c == remaining[0]) {
n = getChildExists(n, c);
remaining = remaining.subspan(1, remaining.size() - 1);
++searchPathLen;
} else {
if (c >= 0) {
if (searchPathLen < prefixLen) {
n = getChildExists(n, c);
goto downLeftSpine;
}
if (maxBetweenExclusive(n, c, 256) > readVersion) {
return false;
if (searchPathLen >= prefixLen) {
if (maxBetweenExclusive(n, remaining[0], 256) > readVersion) {
ok = false;
return true;
}
}
int c = getChildGeq(n, remaining[0]);
if (c == remaining[0]) {
n = getChildExists(n, c);
return n->maxVersion <= readVersion;
remaining = remaining.subspan(1, remaining.size() - 1);
++searchPathLen;
} else {
n = nextSibling(n);
goto downLeftSpine;
}
}
if (n->partialKeyLen > 0) {
int commonLen = std::min<int>(n->partialKeyLen, remaining.size());
for (int i = 0; i < commonLen; ++i) {
auto c = n->partialKey[i] <=> remaining[i];
if (c == 0) {
++searchPathLen;
continue;
}
if (c > 0) {
if (c >= 0) {
if (searchPathLen < prefixLen) {
goto downLeftSpine;
}
if (n->entryPresent && n->entry.rangeVersion > readVersion) {
n = getChildExists(n, c);
phase = DownLeftSpine;
return false;
}
return n->maxVersion <= readVersion;
if (maxBetweenExclusive(n, c, 256) > readVersion) {
ok = false;
return true;
}
n = getChildExists(n, c);
ok = n->maxVersion <= readVersion;
return true;
} else {
n = nextSibling(n);
goto downLeftSpine;
}
}
if (commonLen == n->partialKeyLen) {
// partial key matches
remaining = remaining.subspan(commonLen, remaining.size() - commonLen);
} else if (n->partialKeyLen > int(remaining.size())) {
if (searchPathLen < prefixLen) {
goto downLeftSpine;
}
if (n->entryPresent && n->entry.rangeVersion > readVersion) {
phase = DownLeftSpine;
return false;
}
return n->maxVersion <= readVersion;
}
if (n->partialKeyLen > 0) {
int commonLen = std::min<int>(n->partialKeyLen, remaining.size());
for (int i = 0; i < commonLen; ++i) {
auto c = n->partialKey[i] <=> remaining[i];
if (c == 0) {
++searchPathLen;
continue;
}
if (c > 0) {
if (searchPathLen < prefixLen) {
phase = DownLeftSpine;
return false;
}
if (n->entryPresent && n->entry.rangeVersion > readVersion) {
ok = false;
return true;
}
ok = n->maxVersion <= readVersion;
return true;
} else {
n = nextSibling(n);
phase = DownLeftSpine;
return false;
}
}
if (commonLen == n->partialKeyLen) {
// partial key matches
remaining =
remaining.subspan(commonLen, remaining.size() - commonLen);
} else if (n->partialKeyLen > int(remaining.size())) {
if (searchPathLen < prefixLen) {
phase = DownLeftSpine;
return false;
}
if (n->entryPresent && n->entry.rangeVersion > readVersion) {
ok = false;
return true;
}
ok = n->maxVersion <= readVersion;
return true;
}
}
break;
}
}
downLeftSpine:
if (n == nullptr) {
return true;
}
for (;;) {
if (n->entryPresent) {
return n->entry.rangeVersion <= readVersion;
case DownLeftSpine:
if (n == nullptr) {
ok = true;
return true;
}
for (;;) {
if (n->entryPresent) {
ok = n->entry.rangeVersion <= readVersion;
return true;
}
int c = getChildGeq(n, 0);
assert(c >= 0);
n = getChildExists(n, c);
}
break;
}
int c = getChildGeq(n, 0);
assert(c >= 0);
n = getChildExists(n, c);
return false;
}
}
};
// Return true if the max version among all keys that start with key[:prefixLen]
// that are < key is <= readVersion
@@ -1190,7 +1226,10 @@ bool checkRangeRead(Node *n, std::span<const uint8_t> begin,
return true;
}
if (!checkRangeLeftSide(n, begin, lcp + 1, readVersion)) {
CheckRangeLeftSide checkRangeLeftSide{n, begin, lcp + 1, readVersion};
while (!checkRangeLeftSide.step())
;
if (!checkRangeLeftSide.ok) {
return false;
}