From e73a57388546b86fa8cb01d833fecdd0decc5808 Mon Sep 17 00:00:00 2001
From: Vladimir Dolzhenko <vladimir.dolzhenko@jetbrains.com>
Date: Fri, 3 Apr 2020 22:02:10 +0200
Subject: [PATCH] Fetch analysis results if it is available

The general idea is to try to fetch a full analysis if it is existed in PerFileAnalysisCache instead of go to ResolveElementCache and do analysis there. Do not perform analysis if it is not in PerFileAnalysisCache.

#KT-37467 Fixed
---
 .../resolve/ModuleResolutionFacadeImpl.kt     |  9 +++++-
 .../caches/resolve/ProjectResolutionFacade.kt | 31 +++++++++++++++----
 2 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ModuleResolutionFacadeImpl.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ModuleResolutionFacadeImpl.kt
index c92227486ae..173804cac57 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ModuleResolutionFacadeImpl.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ModuleResolutionFacadeImpl.kt
@@ -57,7 +57,14 @@ internal class ModuleResolutionFacadeImpl(
     override fun analyze(elements: Collection<KtElement>, bodyResolveMode: BodyResolveMode): BindingContext {
         ResolveInDispatchThreadManager.assertNoResolveInDispatchThread()
 
-        if (elements.isEmpty()) return BindingContext.EMPTY
+        when (elements.size) {
+            0 -> return BindingContext.EMPTY
+            1 -> {
+                runWithCancellationCheck {
+                    projectFacade.fetchAnalysisResultsForElement(elements.first())?.bindingContext
+                }?.let { return it }
+            }
+        }
 
         val resolveElementCache = getFrontendService(elements.first(), ResolveElementCache::class.java)
         return runWithCancellationCheck {
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ProjectResolutionFacade.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ProjectResolutionFacade.kt
index f342e967a2d..09e936c7b88 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ProjectResolutionFacade.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ProjectResolutionFacade.kt
@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.resolve.CompositeBindingContext
 import org.jetbrains.kotlin.utils.addToStdlib.firstNotNullResult
+import java.util.concurrent.locks.ReentrantLock
 
 internal class ProjectResolutionFacade(
     private val debugString: String,
@@ -50,12 +51,34 @@ internal class ProjectResolutionFacade(
         {
             val resolverForProject = cachedResolverForProject
             val results = object : SLRUCache<KtFile, PerFileAnalysisCache>(2, 3) {
+                private val lock = ReentrantLock()
+
                 override fun createValue(file: KtFile): PerFileAnalysisCache {
                     return PerFileAnalysisCache(
                         file,
                         resolverForProject.resolverForModule(file.getModuleInfo()).componentProvider
                     )
                 }
+
+                override fun get(key: KtFile?): PerFileAnalysisCache {
+                    lock.lock()
+                    try {
+                        return super.get(key)
+                    } finally {
+                        lock.unlock()
+                    }
+                }
+
+                override fun getIfCached(key: KtFile?): PerFileAnalysisCache? {
+                    if (lock.tryLock()) {
+                        try {
+                            return super.getIfCached(key)
+                        } finally {
+                            lock.unlock()
+                        }
+                    }
+                    return null
+                }
             }
 
             val allDependencies = resolverForProjectDependencies + listOf(
@@ -121,9 +144,7 @@ internal class ProjectResolutionFacade(
             analysisResults.value!!
         }
         val results = elements.map {
-            val perFileCache = synchronized(slruCache) {
-                slruCache[it.containingKtFile]
-            }
+            val perFileCache = slruCache[it.containingKtFile]
             perFileCache.getAnalysisResults(it)
         }
         val withError = results.firstOrNull { it.isError() }
@@ -140,9 +161,7 @@ internal class ProjectResolutionFacade(
         val slruCache = synchronized(analysisResults) {
             analysisResults.upToDateOrNull?.get() ?: return null
         }
-        val perFileCache = synchronized(slruCache) {
-            slruCache.getIfCached(element.containingKtFile)
-        }
+        val perFileCache = slruCache.getIfCached(element.containingKtFile)
         return perFileCache?.fetchAnalysisResults(element)
     }