[CodeGen] Don't emit lifetime.end without lifetime.start

EmitLifetimeStart returns a non-null `size` pointer if it actually
emits a lifetime.start. Later in this function, we use `tempSize`'s
nullness to determine whether or not we should emit a lifetime.end.

llvm-svn: 326844

2 files changed, 10 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index ebba2501cea..187697ee0b6 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -4010,13 +4010,11 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
         auto scalarSize = CGM.getDataLayout().getTypeAllocSize(scalarType);
         auto scalarAlign = CGM.getDataLayout().getPrefTypeAlignment(scalarType);
 
-        tempSize = llvm::ConstantInt::get(CGM.Int64Ty, scalarSize);
-
         // Materialize to a temporary.
         addr = CreateTempAlloca(RV.getScalarVal()->getType(),
                  CharUnits::fromQuantity(std::max(layout->getAlignment(),
                                                   scalarAlign)));
-        EmitLifetimeStart(scalarSize, addr.getPointer());
+        tempSize = EmitLifetimeStart(scalarSize, addr.getPointer());
 
         Builder.CreateStore(RV.getScalarVal(), addr);
       }
diff --git a/clang/test/CodeGen/64bit-swiftcall.c b/clang/test/CodeGen/64bit-swiftcall.c
index c5944b99b59..2eed2a4b290 100644
--- a/clang/test/CodeGen/64bit-swiftcall.c
+++ b/clang/test/CodeGen/64bit-swiftcall.c
@@ -1032,3 +1032,12 @@ typedef union {
 TEST(union_hom_fp_partial2)
 // X86-64-LABEL: take_union_hom_fp_partial2(i64, float)
 // ARM64-LABEL: take_union_hom_fp_partial2(i64, float)
+
+// At one point, we emitted lifetime.ends without a matching lifetime.begin for
+// CoerceAndExpanded args. Since we're not performing optimizations, neither
+// intrinsic should be emitted.
+// CHECK-LABEL: define void @no_lifetime_markers
+void no_lifetime_markers() {
+  // CHECK-NOT: call void @llvm.lifetime.
+  take_int5(return_int5());
+}