Add an optimization to support the most common access pattern for the
library. This speeds debug builds up significantly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3826 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/LeakDetector.cpp b/lib/Support/LeakDetector.cpp
index 3dbd2e6..ecc4868 100644
--- a/lib/Support/LeakDetector.cpp
+++ b/lib/Support/LeakDetector.cpp
@@ -12,6 +12,13 @@
static std::set<const void*> *Objects = 0;
static std::set<const Value*> *LLVMObjects = 0;
+// Because the most common usage pattern, by far, is to add a garbage object,
+// then remove it immediately, we optimize this case. When an object is added,
+// it is not added to the set immediately, it is added to the CachedValue Value.
+// If it is immediately removed, no set search need be performed.
+//
+static const Value *CachedValue;
+
void LeakDetector::addGarbageObjectImpl(void *Object) {
if (Objects == 0)
Objects = new std::set<const void*>();
@@ -25,18 +32,28 @@
}
void LeakDetector::addGarbageObjectImpl(const Value *Object) {
- if (LLVMObjects == 0)
- LLVMObjects = new std::set<const Value*>();
- assert(LLVMObjects->count(Object) == 0 && "Object already in set!");
- LLVMObjects->insert(Object);
+ if (CachedValue) {
+ if (LLVMObjects == 0)
+ LLVMObjects = new std::set<const Value*>();
+ assert(LLVMObjects->count(CachedValue) == 0 && "Object already in set!");
+ LLVMObjects->insert(CachedValue);
+ }
+ CachedValue = Object;
}
void LeakDetector::removeGarbageObjectImpl(const Value *Object) {
- if (LLVMObjects)
+ if (Object == CachedValue)
+ CachedValue = 0; // Cache hit!
+ else if (LLVMObjects)
LLVMObjects->erase(Object);
}
void LeakDetector::checkForGarbageImpl(const std::string &Message) {
+ if (CachedValue) // Flush the cache to the set...
+ addGarbageObjectImpl((Value*)0);
+
+ assert(CachedValue == 0 && "No value should be cached anymore!");
+
if ((Objects && !Objects->empty()) || (LLVMObjects && !LLVMObjects->empty())){
std::cerr << "Leaked objects found: " << Message << "\n";