1 ; RUN: llc -O2 < %s | FileCheck %s 2 3 ; The call to function TestBar should be a tail call, when in C++ the string 4 ; `ret` is RVO returned. 5 ; string TestFoo() { 6 ; string ret = undef; 7 ; TestBar(&ret); // tail call optimized 8 ; return ret; 9 ; } 10 11 target triple = "powerpc64le-linux-gnu" 12 13 %class.basic_string.11.42.73 = type { %"class.__gnu_cxx::__versa_string.10.41.72" } 14 %"class.__gnu_cxx::__versa_string.10.41.72" = type { %"class.__gnu_cxx::__sso_string_base.9.40.71" } 15 %"class.__gnu_cxx::__sso_string_base.9.40.71" = type { %"struct.__gnu_cxx::__vstring_utility<char, std::char_traits<char>, std::allocator<char> >::_Alloc_hider.7.38.69", i64, %union.anon.8.39.70 } 16 %"struct.__gnu_cxx::__vstring_utility<char, std::char_traits<char>, std::allocator<char> >::_Alloc_hider.7.38.69" = type { i8* } 17 %union.anon.8.39.70 = type { i64, [8 x i8] } 18 19 declare void @TestBaz(%class.basic_string.11.42.73* noalias sret %arg) 20 21 define void @TestBar(%class.basic_string.11.42.73* noalias sret %arg) { 22 bb: 23 call void @TestBaz(%class.basic_string.11.42.73* noalias sret %arg) 24 ret void 25 } 26 27 define void @TestFoo(%class.basic_string.11.42.73* noalias sret %arg) { 28 ; CHECK-LABEL: TestFoo: 29 ; CHECK: #TC_RETURNd8 TestBar 0 30 bb: 31 %tmp = getelementptr inbounds %class.basic_string.11.42.73, %class.basic_string.11.42.73* %arg, i64 0, i32 0, i32 0, i32 2 32 %tmp1 = bitcast %class.basic_string.11.42.73* %arg to %union.anon.8.39.70** 33 store %union.anon.8.39.70* %tmp, %union.anon.8.39.70** %tmp1, align 8 34 %tmp2 = bitcast %union.anon.8.39.70* %tmp to i8* 35 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %tmp2, i8* nonnull undef, i64 13, i32 1, i1 false) 36 %tmp3 = getelementptr inbounds %class.basic_string.11.42.73, %class.basic_string.11.42.73* %arg, i64 0, i32 0, i32 0, i32 1 37 store i64 13, i64* %tmp3, align 8 38 %tmp4 = getelementptr inbounds %class.basic_string.11.42.73, %class.basic_string.11.42.73* %arg, i64 0, i32 0, i32 0, i32 2, i32 1, i64 5 39 store i8 0, i8* %tmp4, align 1 40 tail call void @TestBar(%class.basic_string.11.42.73* noalias sret %arg) 41 ret void 42 } 43 44 ; Function Attrs: argmemonly nounwind 45 declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) #0 46 47 attributes #0 = { argmemonly nounwind } 48
