1 files changed, 40 insertions, 7 deletions
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index f168dd02ead..c8ba352e233 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -498,18 +498,51 @@ EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
   } else {
     switch (M->getStorageDuration()) {
     case SD_Automatic:
-    case SD_FullExpression:
       if (auto *Size = EmitLifetimeStart(
               CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
               Alloca.getPointer())) {
-        if (M->getStorageDuration() == SD_Automatic)
-          pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
-                                                    Alloca, Size);
-        else
-          pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
-                                               Size);
+        pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
+                                                  Alloca, Size);
       }
       break;
+
+    case SD_FullExpression: {
+      if (!ShouldEmitLifetimeMarkers)
+        break;
+
+      // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end
+      // marker. Instead, start the lifetime of a conditional temporary earlier
+      // so that it's unconditional. Don't do this in ASan's use-after-scope
+      // mode so that it gets the more precise lifetime marks. If the type has
+      // a non-trivial destructor, we'll have a cleanup block for it anyway,
+      // so this typically doesn't help; skip it in that case.
+      ConditionalEvaluation *OldConditional = nullptr;
+      CGBuilderTy::InsertPoint OldIP;
+      if (isInConditionalBranch() && !E->getType().isDestructedType() &&
+          !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) {
+        OldConditional = OutermostConditional;
+        OutermostConditional = nullptr;
+
+        OldIP = Builder.saveIP();
+        llvm::BasicBlock *Block = OldConditional->getStartingBlock();
+        Builder.restoreIP(CGBuilderTy::InsertPoint(
+            Block, llvm::BasicBlock::iterator(Block->back())));
+      }
+
+      if (auto *Size = EmitLifetimeStart(
+              CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
+              Alloca.getPointer())) {
+        pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
+                                             Size);
+      }
+
+      if (OldConditional) {
+        OutermostConditional = OldConditional;
+        Builder.restoreIP(OldIP);
+      }
+      break;
+    }
+
     default:
       break;
     }