diff --git a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProvider.kt b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProvider.kt
index d5ceb1488d2..fc0e3a3a961 100644
--- a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProvider.kt
+++ b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProvider.kt
@@ -6,20 +6,20 @@
 package org.jetbrains.kotlin.analysis.low.level.api.fir.sessions
 
 import com.intellij.openapi.project.Project
+import org.jetbrains.annotations.TestOnly
 import org.jetbrains.kotlin.analysis.api.impl.barebone.annotations.Immutable
 import org.jetbrains.kotlin.analysis.low.level.api.fir.project.structure.LLFirModuleData
-import org.jetbrains.kotlin.analysis.low.level.api.fir.providers.LLFirDependentModuleProviders
 import org.jetbrains.kotlin.analysis.project.structure.KtModule
 import org.jetbrains.kotlin.analysis.utils.errors.requireIsInstance
 import org.jetbrains.kotlin.fir.FirModuleData
 import org.jetbrains.kotlin.fir.FirSessionProvider
-import org.jetbrains.kotlin.fir.resolve.providers.dependenciesSymbolProvider
+import java.lang.ref.WeakReference
 
 @Immutable
 class LLFirSessionProvider internal constructor(
     val project: Project,
     internal val rootModuleSession: LLFirResolvableModuleSession,
-    private val ktModuleToSession: Map<KtModule, LLFirSession>
+    private val ktModuleToSession: KtModuleToSessionMapping
 ) : FirSessionProvider() {
     override fun getSession(moduleData: FirModuleData): LLFirSession {
         requireIsInstance<LLFirModuleData>(moduleData)
@@ -27,11 +27,44 @@ class LLFirSessionProvider internal constructor(
     }
 
     fun getSession(module: KtModule): LLFirSession =
-        ktModuleToSession.getValue(module)
+        ktModuleToSession.getSession(module)
 
     fun getResolvableSession(module: KtModule): LLFirResolvableModuleSession =
-        ktModuleToSession.getValue(module) as LLFirResolvableModuleSession
+        ktModuleToSession.getSession(module) as LLFirResolvableModuleSession
 
+    @get:TestOnly
     val allSessions: Collection<LLFirSession>
-        get() = ktModuleToSession.values
+        get() = ktModuleToSession.getAllSessions()
 }
+
+internal abstract class KtModuleToSessionMapping {
+    abstract fun getSession(module: KtModule): LLFirSession
+
+    @TestOnly
+    abstract fun getAllSessions(): Collection<LLFirSession>
+}
+
+internal class KtModuleToSessionMappingByMapImpl(
+    private val map: Map<KtModule, LLFirSession>
+) : KtModuleToSessionMapping() {
+    override fun getSession(module: KtModule): LLFirSession =
+        map.getValue(module)
+
+    override fun getAllSessions(): Collection<LLFirSession> =
+        map.values
+}
+
+internal class KtModuleToSessionMappingByWeakValueMapImpl(
+    initialMap: Map<KtModule, LLFirSession>
+) : KtModuleToSessionMapping() {
+    private val softValuesMap = initialMap.entries.associate { (key, value) -> key to WeakReference(value) }
+
+    override fun getSession(module: KtModule): LLFirSession {
+        val softReference = softValuesMap.getValue(module)
+        return softReference.get()
+            ?: error("soft reference for $module was invalidated")
+    }
+
+    override fun getAllSessions(): Collection<LLFirSession> =
+        softValuesMap.keys.map { getSession(it) }
+}
\ No newline at end of file
diff --git a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProviderStorage.kt b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProviderStorage.kt
index f97db309bf6..3cc6465206e 100644
--- a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProviderStorage.kt
+++ b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionProviderStorage.kt
@@ -48,7 +48,7 @@ class LLFirSessionProviderStorage(val project: Project) {
             is KtNotUnderContentRootModule -> {
                 val session = LLFirNonUnderContentRootSessionFactory.getInstance(project)
                     .getNonUnderContentRootSession(useSiteKtModule)
-                LLFirSessionProvider(project, session, mapOf(useSiteKtModule to session))
+                LLFirSessionProvider(project, session, KtModuleToSessionMappingByMapImpl(mapOf(useSiteKtModule to session)))
             }
 
             else -> error("Unexpected ${useSiteKtModule::class.simpleName}")
@@ -72,7 +72,7 @@ class LLFirSessionProviderStorage(val project: Project) {
             )
             sessions to session
         }
-        return LLFirSessionProvider(project, session, sessions)
+        return LLFirSessionProvider(project, session, KtModuleToSessionMappingByWeakValueMapImpl(sessions))
     }
 
 
@@ -93,7 +93,7 @@ class LLFirSessionProviderStorage(val project: Project) {
             )
             sessions to session
         }
-        return LLFirSessionProvider(project, session, sessions)
+        return LLFirSessionProvider(project, session, KtModuleToSessionMappingByWeakValueMapImpl(sessions))
     }
 }