18ad9e1ecSStephen Tozer // RUN: %clang_cc1 %s -triple x86_64-unknown-linux-gnu -emit-llvm -fextend-variable-liveness -fsanitize=null -fsanitize-trap=null -o - | FileCheck --check-prefixes=CHECK,NULL --implicit-check-not=ubsantrap %s 28ad9e1ecSStephen Tozer // RUN: %clang_cc1 %s -triple x86_64-unknown-linux-gnu -emit-llvm -fextend-variable-liveness -o - | FileCheck %s 34424c44cSWolfgang Pieb 4*822f74a9SStephen Tozer // With -fextend-variable-liveness, the compiler previously generated a fake.use of any 54424c44cSWolfgang Pieb // reference variable at the end of the scope in which its alloca exists. This 64424c44cSWolfgang Pieb // caused two issues, where we would get fake uses for uninitialized variables 74424c44cSWolfgang Pieb // if that variable was declared after an early-return, and UBSan's null checks 84424c44cSWolfgang Pieb // would complain about this. 94424c44cSWolfgang Pieb // This test verifies that UBSan does not produce null-checks for arguments to 104424c44cSWolfgang Pieb // llvm.fake.use, and that fake uses are not emitted for a variable on paths 114424c44cSWolfgang Pieb // it has not been declared. 124424c44cSWolfgang Pieb 134424c44cSWolfgang Pieb struct A { short s1, s2; }; 144424c44cSWolfgang Pieb extern long& getA(); 154424c44cSWolfgang Pieb 164424c44cSWolfgang Pieb void foo() 174424c44cSWolfgang Pieb { 184424c44cSWolfgang Pieb auto& va = getA(); 194424c44cSWolfgang Pieb if (va < 5) 204424c44cSWolfgang Pieb return; 214424c44cSWolfgang Pieb 224424c44cSWolfgang Pieb auto& vb = getA(); 234424c44cSWolfgang Pieb } 244424c44cSWolfgang Pieb 254424c44cSWolfgang Pieb // CHECK-LABEL: define{{.*}}foo 264424c44cSWolfgang Pieb // CHECK: [[VA_CALL:%.+]] = call{{.*}} ptr @_Z4getAv() 274424c44cSWolfgang Pieb 284424c44cSWolfgang Pieb /// We check here for the first UBSan check for "va". 294424c44cSWolfgang Pieb // NULL: [[VA_ISNULL:%.+]] = icmp ne ptr [[VA_CALL]], null 304424c44cSWolfgang Pieb // NULL: br i1 [[VA_ISNULL]], label %{{[^,]+}}, label %[[VA_TRAP:[^,]+]] 314424c44cSWolfgang Pieb // NULL: [[VA_TRAP]]: 324424c44cSWolfgang Pieb // NULL: call void @llvm.ubsantrap( 334424c44cSWolfgang Pieb 344424c44cSWolfgang Pieb // CHECK: [[VA_PTR:%.+]] = load ptr, ptr %va 354424c44cSWolfgang Pieb // CHECK-NEXT: [[VA_CMP:%.+]] = load i64, ptr [[VA_PTR]] 364424c44cSWolfgang Pieb // CHECK-NEXT: [[VA_CMP_RES:%.+]] = icmp slt i64 [[VA_CMP]], 5 374424c44cSWolfgang Pieb // CHECK-NEXT: br i1 [[VA_CMP_RES]], label %[[EARLY_EXIT:[^,]+]], label %[[NOT_EARLY_EXIT:[^,]+]] 384424c44cSWolfgang Pieb 394424c44cSWolfgang Pieb // CHECK: [[EARLY_EXIT]]: 404424c44cSWolfgang Pieb // CHECK: br label %cleanup 414424c44cSWolfgang Pieb 424424c44cSWolfgang Pieb /// The fake use for "vb" only appears on the path where its declaration is 434424c44cSWolfgang Pieb /// reached. 444424c44cSWolfgang Pieb // CHECK: [[NOT_EARLY_EXIT]]: 454424c44cSWolfgang Pieb // CHECK: [[VB_CALL:%.+]] = call{{.*}} ptr @_Z4getAv() 464424c44cSWolfgang Pieb 474424c44cSWolfgang Pieb /// We check here for the second UBSan check for "vb". 484424c44cSWolfgang Pieb // NULL: [[VB_ISNULL:%.+]] = icmp ne ptr [[VB_CALL]], null 494424c44cSWolfgang Pieb // NULL: br i1 [[VB_ISNULL]], label %{{[^,]+}}, label %[[VB_TRAP:[^,]+]] 504424c44cSWolfgang Pieb // NULL: [[VB_TRAP]]: 514424c44cSWolfgang Pieb // NULL: call void @llvm.ubsantrap( 524424c44cSWolfgang Pieb 534424c44cSWolfgang Pieb // CHECK: [[VB_FAKE_USE:%.+]] = load ptr, ptr %vb 544424c44cSWolfgang Pieb // CHECK-NEXT: call void (...) @llvm.fake.use(ptr [[VB_FAKE_USE]]) 554424c44cSWolfgang Pieb // CHECK: br label %cleanup 564424c44cSWolfgang Pieb 574424c44cSWolfgang Pieb // CHECK: cleanup: 584424c44cSWolfgang Pieb // CHECK: [[VA_FAKE_USE:%.+]] = load ptr, ptr %va 594424c44cSWolfgang Pieb // CHECK-NEXT: call void (...) @llvm.fake.use(ptr [[VA_FAKE_USE]]) 604424c44cSWolfgang Pieb 614424c44cSWolfgang Pieb // NULL: declare void @llvm.ubsantrap 62