Author: Weining Lu Date: 2023-07-25T09:18:06+08:00 New Revision: 983f2488326e1f8034f3b0686cd44221d8697bdc
URL: https://github.com/llvm/llvm-project/commit/983f2488326e1f8034f3b0686cd44221d8697bdc DIFF: https://github.com/llvm/llvm-project/commit/983f2488326e1f8034f3b0686cd44221d8697bdc.diff LOG: Revert "[Clang][LoongArch] Fix ABI handling of empty structs in C++ to match GCC behaviour" This reverts commit c299efbf284fae92bb8d7d29110f76912f089daf. Reason to revert: D142327 has been reverted which is depended by this change. Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/CodeGen/Targets/LoongArch.cpp clang/test/CodeGen/LoongArch/abi-lp64d-empty-structs.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 45753a651e723a..13fb95b8767c3b 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -891,8 +891,6 @@ LoongArch Support on LoongArch. - Unaligned memory accesses can be toggled by ``-m[no-]unaligned-access`` or the aliases ``-m[no-]strict-align``. -- An ABI mismatch between GCC and Clang related to the handling of empty structs - in C++ parameter passing under ``lp64d`` ABI was fixed. RISC-V Support ^^^^^^^^^^^^^^ diff --git a/clang/lib/CodeGen/Targets/LoongArch.cpp b/clang/lib/CodeGen/Targets/LoongArch.cpp index 056b3946d1b33f..6391a8aeaa67cd 100644 --- a/clang/lib/CodeGen/Targets/LoongArch.cpp +++ b/clang/lib/CodeGen/Targets/LoongArch.cpp @@ -148,13 +148,6 @@ bool LoongArchABIInfo::detectFARsEligibleStructHelper( if (const ConstantArrayType *ATy = getContext().getAsConstantArrayType(Ty)) { uint64_t ArraySize = ATy->getSize().getZExtValue(); QualType EltTy = ATy->getElementType(); - // Non-zero-length arrays of empty records make the struct ineligible to be - // passed via FARs in C++. - if (const auto *RTy = EltTy->getAs<RecordType>()) { - if (ArraySize != 0 && isa<CXXRecordDecl>(RTy->getDecl()) && - isEmptyRecord(getContext(), EltTy, true, true)) - return false; - } CharUnits EltSize = getContext().getTypeSizeInChars(EltTy); for (uint64_t i = 0; i < ArraySize; ++i) { if (!detectFARsEligibleStructHelper(EltTy, CurOff, Field1Ty, Field1Off, @@ -170,7 +163,7 @@ bool LoongArchABIInfo::detectFARsEligibleStructHelper( // copy constructor are not eligible for the FP calling convention. if (getRecordArgABI(Ty, CGT.getCXXABI())) return false; - if (isEmptyRecord(getContext(), Ty, true, true)) + if (isEmptyRecord(getContext(), Ty, true)) return true; const RecordDecl *RD = RTy->getDecl(); // Unions aren't eligible unless they're empty (which is caught above). diff --git a/clang/test/CodeGen/LoongArch/abi-lp64d-empty-structs.c b/clang/test/CodeGen/LoongArch/abi-lp64d-empty-structs.c index b5c7916f57cd99..3a65b90e48e0e0 100644 --- a/clang/test/CodeGen/LoongArch/abi-lp64d-empty-structs.c +++ b/clang/test/CodeGen/LoongArch/abi-lp64d-empty-structs.c @@ -3,6 +3,7 @@ // RUN: %clang_cc1 -triple loongarch64 -target-feature +f -target-feature +d -target-abi lp64d -emit-llvm %s -o - -x c++ | \ // RUN: FileCheck --check-prefix=CHECK-CXX %s +// FIXME: This isn't currently respected. // Fields containing empty structs or unions are ignored when flattening // structs to examine whether the structs can be passed via FARs, even in C++. // But there is an exception that non-zero-length array of empty structures are @@ -15,7 +16,7 @@ struct empty { struct { struct { } e; }; }; struct s1 { struct empty e; float f; }; // CHECK-C: define{{.*}} float @test_s1(float {{.*}}) -// CHECK-CXX: define{{.*}} float @_Z7test_s12s1(float {{.*}}) +// CHECK-CXX: define{{.*}} i64 @_Z7test_s12s1(i64 {{.*}}) struct s1 test_s1(struct s1 a) { return a; } @@ -23,7 +24,7 @@ struct s1 test_s1(struct s1 a) { struct s2 { struct empty e; int32_t i; float f; }; // CHECK-C: define{{.*}} { i32, float } @test_s2(i32 {{.*}}, float {{.*}}) -// CHECK-CXX: define{{.*}} { i32, float } @_Z7test_s22s2(i32 {{.*}}, float {{.*}}) +// CHECK-CXX: define{{.*}} [2 x i64] @_Z7test_s22s2([2 x i64] {{.*}}) struct s2 test_s2(struct s2 a) { return a; } @@ -31,7 +32,7 @@ struct s2 test_s2(struct s2 a) { struct s3 { struct empty e; float f; float g; }; // CHECK-C: define{{.*}} { float, float } @test_s3(float {{.*}}, float {{.*}}) -// CHECK-CXX: define{{.*}} { float, float } @_Z7test_s32s3(float {{.*}}, float {{.*}}) +// CHECK-CXX: define{{.*}} [2 x i64] @_Z7test_s32s3([2 x i64] {{.*}}) struct s3 test_s3(struct s3 a) { return a; } @@ -39,7 +40,7 @@ struct s3 test_s3(struct s3 a) { struct s4 { struct empty e; float __complex__ c; }; // CHECK-C: define{{.*}} { float, float } @test_s4(float {{.*}}, float {{.*}}) -// CHECK-CXX: define{{.*}} { float, float } @_Z7test_s42s4(float {{.*}}, float {{.*}}) +// CHECK-CXX: define{{.*}} [2 x i64] @_Z7test_s42s4([2 x i64] {{.*}}) struct s4 test_s4(struct s4 a) { return a; } @@ -76,7 +77,7 @@ struct empty_arr0 { struct { struct { } e[0]; }; }; struct s8 { struct empty_arr0 e; float f; }; // CHECK-C: define{{.*}} float @test_s8(float {{.*}}) -// CHECK-CXX: define{{.*}} float @_Z7test_s82s8(float {{.*}}) +// CHECK-CXX: define{{.*}} i64 @_Z7test_s82s8(i64 {{.*}}) struct s8 test_s8(struct s8 a) { return a; } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
