[clang] 983f248 - Revert "[Clang][LoongArch] Fix ABI handling of empty structs in C++ to match GCC behaviour"
Weining Lu via cfe-commits
cfe-commits at lists.llvm.org
Mon Jul 24 18:18:54 PDT 2023
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;
}
More information about the cfe-commits
mailing list