https://github.com/zmodem created https://github.com/llvm/llvm-project/pull/196505
This fixes two issues where Clang was both over- and under-aligning variables: 1) We were applying the x86_64 psABI "large array" alignment increase (default when inheriting from X86_64TargetInfo), but MSVC doesn't follow that ABI. 2) MSVC implements a similar scheme though, where it increases the alignment of large objects. This is documented for ARM64 [1] and was implemented in Clang b7c6d95af5e295c560d1445e7090e31eb9289932, but it also applies to x86_64. ([2] says "MSVC does size (total size, not element size) based alignment for global symbols on ARM64 *which is copied from AMD64*"). [1] https://learn.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions?view=msvc-170#alignment [2] https://github.com/llvm/llvm-project/issues/40851 Fixes https://github.com/llvm/llvm-project/issues/196071 Fixes https://github.com/llvm/llvm-project/issues/171855 >From 18afb6f6f9f6f25cd2d708a495a9c112aeddf708 Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 09:45:30 +0200 Subject: [PATCH 1/7] Don't apply the 'large array' alignment increase for x86_64-windows-msvc; it doesn't follow the psABI (https://github.com/llvm/llvm-project/issues/196071) --- clang/lib/Basic/Targets/X86.h | 2 ++ clang/test/CodeGen/align-x68_64.c | 9 +++++++++ 2 files changed, 11 insertions(+) diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h index c7afcc7c86053..e6f798834d11c 100644 --- a/clang/lib/Basic/Targets/X86.h +++ b/clang/lib/Basic/Targets/X86.h @@ -968,6 +968,8 @@ class LLVM_LIBRARY_VISIBILITY MicrosoftX86_64TargetInfo : WindowsX86_64TargetInfo(Triple, Opts) { LongDoubleWidth = LongDoubleAlign = 64; LongDoubleFormat = &llvm::APFloat::IEEEdouble(); + LargeArrayMinWidth = 0; + LargeArrayAlign = 0; } void getTargetDefines(const LangOptions &Opts, diff --git a/clang/test/CodeGen/align-x68_64.c b/clang/test/CodeGen/align-x68_64.c index cf128b43433ea..01a3f34e6d321 100644 --- a/clang/test/CodeGen/align-x68_64.c +++ b/clang/test/CodeGen/align-x68_64.c @@ -1,11 +1,20 @@ // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm %s -o - | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-windows-gnu -emit-llvm %s -o - | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm %s -o - | FileCheck --check-prefix=MSVC %s // PR5599 +char arr[16]; + void test1_f(void *); void test1_g(void) { float x[4]; test1_f(x); } +// CHECK: @arr = {{.*}} align 16 // CHECK: @test1_g // CHECK: alloca [4 x float], align 16 + +// MSVC: @arr = {{.*}} align 1 +// MSVC: @test1_g +// MSVC: alloca [4 x float], align 4 >From eb30e4051f22f63b54d4b5bda6c860717067fd1c Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 10:25:40 +0200 Subject: [PATCH 2/7] implement MicrosoftX86_64TargetInfo::getMinGlobalAlign --- clang/lib/Basic/Targets/X86.cpp | 21 +++++++++++++++++++ clang/lib/Basic/Targets/X86.h | 3 +++ .../CodeGen/arm64-microsoft-struct-align.cpp | 2 ++ 3 files changed, 26 insertions(+) diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp index cb941c94c84a7..f0227be035ee3 100644 --- a/clang/lib/Basic/Targets/X86.cpp +++ b/clang/lib/Basic/Targets/X86.cpp @@ -1852,3 +1852,24 @@ X86_64TargetInfo::getTargetBuiltins() const { "__builtin_ia32_"}, }; } + +unsigned +MicrosoftX86_64TargetInfo::getMinGlobalAlign(uint64_t TypeSize, + bool HasNonWeakDef) const { + // XXX: copy-pasted. can we share the code? + unsigned Align = + WindowsX86_64TargetInfo::getMinGlobalAlign(TypeSize, HasNonWeakDef); + + // MSVC does size based alignment for arm64 based on alignment section in + // below document, replicate that to keep alignment consistent with object + // files compiled by MSVC. + // https://docs.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions + if (TypeSize >= 512) { // TypeSize >= 64 bytes + Align = std::max(Align, 128u); // align type at least 16 bytes + } else if (TypeSize >= 64) { // TypeSize >= 8 bytes + Align = std::max(Align, 64u); // align type at least 8 butes + } else if (TypeSize >= 16) { // TypeSize >= 2 bytes + Align = std::max(Align, 32u); // align type at least 4 bytes + } + return Align; +} diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h index e6f798834d11c..c8c5d280754b4 100644 --- a/clang/lib/Basic/Targets/X86.h +++ b/clang/lib/Basic/Targets/X86.h @@ -983,6 +983,9 @@ class LLVM_LIBRARY_VISIBILITY MicrosoftX86_64TargetInfo getCallingConvKind(bool ClangABICompat4) const override { return CCK_MicrosoftWin64; } + + unsigned getMinGlobalAlign(uint64_t TypeSize, + bool HasNonWeakDef) const override; }; // x86-64 MinGW target diff --git a/clang/test/CodeGen/arm64-microsoft-struct-align.cpp b/clang/test/CodeGen/arm64-microsoft-struct-align.cpp index 4076c3ca34ad7..60bb9e2fc5405 100644 --- a/clang/test/CodeGen/arm64-microsoft-struct-align.cpp +++ b/clang/test/CodeGen/arm64-microsoft-struct-align.cpp @@ -1,6 +1,8 @@ // RUN: %clang_cc1 -triple aarch64-windows -ffreestanding -emit-llvm -O0 \ // RUN: -x c++ -o - %s | FileCheck %s +// FIXME: add tests here. + struct size1 { char str[1]; }; struct size2 { char str[2]; }; struct size7 { char str[4]; }; >From efa8384116d24f0f3530e0f343e226f49fb162a8 Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 10:43:22 +0200 Subject: [PATCH 3/7] remove alignment checks from clang/test/CodeGen/c-strings.c --- clang/test/CodeGen/c-strings.c | 30 ++++-------------------------- 1 file changed, 4 insertions(+), 26 deletions(-) diff --git a/clang/test/CodeGen/c-strings.c b/clang/test/CodeGen/c-strings.c index 31c438fd8ff2e..60d434f37a20d 100644 --- a/clang/test/CodeGen/c-strings.c +++ b/clang/test/CodeGen/c-strings.c @@ -4,37 +4,15 @@ // Should be 3 hello strings, two global (of different sizes), the rest are // shared. -// CHECK: @align = {{(dso_local )?}}global i8 [[ALIGN:[0-9]+]] // ITANIUM: @.str = private unnamed_addr constant [6 x i8] c"hello\00" -// MSABI: @"??_C@_05CJBACGMB@hello?$AA@" = linkonce_odr dso_local unnamed_addr constant [6 x i8] c"hello\00", comdat, align 1 +// MSABI: @"??_C@_05CJBACGMB@hello?$AA@" = linkonce_odr dso_local unnamed_addr constant [6 x i8] c"hello\00", comdat // ITANIUM: @f1.x = internal global ptr @.str // MSABI: @f1.x = internal global ptr @"??_C@_05CJBACGMB@hello?$AA@" -// CHECK: @f2.x = internal global [6 x i8] c"hello\00", align [[ALIGN]] -// CHECK: @f3.x = internal global [8 x i8] c"hello\00\00\00", align [[ALIGN]] +// CHECK: @f2.x = internal global [6 x i8] c"hello\00" +// CHECK: @f3.x = internal global [8 x i8] c"hello\00\00\00" // ITANIUM: @f4.x = internal global %struct.s { ptr @.str } // MSABI: @f4.x = internal global %struct.s { ptr @"??_C@_05CJBACGMB@hello?$AA@" } -// CHECK: @x = {{(dso_local )?}}global [3 x i8] c"ola", align [[ALIGN]] - -// XFAIL: target=aarch64-{{.*}}-windows-msvc, target=arm64ec-{{.*}}-windows-msvc -// Arm64 in MSVC mode aligns arrays to either 32-bit or 64-bit boundaries, which fails -// various checks above, since ALIGN is derived from the alignment of a single -// i8, which is still 1. - -// XFAIL: target=hexagon-{{.*}} -// Hexagon aligns arrays of size 8+ bytes to a 64-bit boundary, which -// fails the check for "@f3.x = ... align [ALIGN]", since ALIGN is derived -// from the alignment of a single i8, which is still 1. - -// XFAIL: target=csky{{.*}} -// CSKY aligns arrays of size 4+ bytes to a 32-bit boundary, which -// fails the check for "@f2.x = ... align [ALIGN]", since ALIGN is derived -// from the alignment of a single i8, which is still 1. - -#if defined(__s390x__) -unsigned char align = 2; -#else -unsigned char align = 1; -#endif +// CHECK: @x = {{(dso_local )?}}global [3 x i8] c"ola" void bar(const char *); >From 512728acf14f772099c6a6cd1fd3b08b204383cc Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 10:51:27 +0200 Subject: [PATCH 4/7] update tests --- clang/test/CodeGen/align-x68_64.c | 2 +- clang/test/CodeGen/asan-strings.c | 4 ++-- .../ms-constexpr-static-data-member.cpp | 4 ++-- clang/test/CodeGenObjC/encode-test-6.m | 2 +- .../CodeGenSYCL/kernel-caller-entry-point.cpp | 16 ++++++++-------- 5 files changed, 14 insertions(+), 14 deletions(-) diff --git a/clang/test/CodeGen/align-x68_64.c b/clang/test/CodeGen/align-x68_64.c index 01a3f34e6d321..94f967b6941d8 100644 --- a/clang/test/CodeGen/align-x68_64.c +++ b/clang/test/CodeGen/align-x68_64.c @@ -15,6 +15,6 @@ void test1_g(void) { // CHECK: @test1_g // CHECK: alloca [4 x float], align 16 -// MSVC: @arr = {{.*}} align 1 +// MSVC: @arr = {{.*}} align 8 // MSVC: @test1_g // MSVC: alloca [4 x float], align 4 diff --git a/clang/test/CodeGen/asan-strings.c b/clang/test/CodeGen/asan-strings.c index 0c7420034f89e..e71445eaf7fe4 100644 --- a/clang/test/CodeGen/asan-strings.c +++ b/clang/test/CodeGen/asan-strings.c @@ -12,6 +12,6 @@ const char *foo(void) { return "asdf"; } // LINUX: @.str = private unnamed_addr constant [5 x i8] c"asdf\00", align 1 -// WINDOWS: @"??_C@_04JIHMPGLA@asdf?$AA@" = linkonce_odr dso_local unnamed_addr constant [5 x i8] c"asdf\00", comdat, align 1 +// WINDOWS: @"??_C@_04JIHMPGLA@asdf?$AA@" = linkonce_odr dso_local unnamed_addr constant [5 x i8] c"asdf\00", comdat, align 4 -// WINWRITE: @.str = private unnamed_addr global [5 x i8] c"asdf\00", align 1 +// WINWRITE: @.str = private unnamed_addr global [5 x i8] c"asdf\00", align 4 diff --git a/clang/test/CodeGenCXX/ms-constexpr-static-data-member.cpp b/clang/test/CodeGenCXX/ms-constexpr-static-data-member.cpp index 604a49fefbacb..4b191fd472c20 100644 --- a/clang/test/CodeGenCXX/ms-constexpr-static-data-member.cpp +++ b/clang/test/CodeGenCXX/ms-constexpr-static-data-member.cpp @@ -19,8 +19,8 @@ void usethem() { useptr(&S::sdm_udt); } -// CHECK-DAG: @"?sdm_char_array@S@@2QBDB" = linkonce_odr dso_local constant [5 x i8] c"asdf\00", comdat, align 1 +// CHECK-DAG: @"?sdm_char_array@S@@2QBDB" = linkonce_odr dso_local constant [5 x i8] c"asdf\00", comdat, align 4 // CHECK-DAG: @"?sdm_char_ptr@S@@2QEBDEB" = linkonce_odr dso_local constant ptr @"??_C@_04JIHMPGLA@asdf?$AA@", comdat, align 8 -// CHECK-DAG: @"?sdm_udt@S@@2UFoo@@B" = linkonce_odr dso_local constant %struct.Foo { i32 1, i32 2 }, comdat, align 4 +// CHECK-DAG: @"?sdm_udt@S@@2UFoo@@B" = linkonce_odr dso_local constant %struct.Foo { i32 1, i32 2 }, comdat, align 8 diff --git a/clang/test/CodeGenObjC/encode-test-6.m b/clang/test/CodeGenObjC/encode-test-6.m index c32f8f24c0009..dd770f523e2f3 100644 --- a/clang/test/CodeGenObjC/encode-test-6.m +++ b/clang/test/CodeGenObjC/encode-test-6.m @@ -80,6 +80,6 @@ @implementation SCNCamera // CHECK-DWARF: define{{.*}} ptr @Test() // CHECK-DWARF: ret ptr @e -// CHECK-MSVC: @e = dso_local global [2 x i8] c"i\00", align 1 +// CHECK-MSVC: @e = dso_local global [2 x i8] c"i\00", align 4 // CHECK-MINGW: @e = dso_local global [2 x i8] c"i\00", align 1 // CHECK-ELF: @e = global [2 x i8] c"i\00", align 1 diff --git a/clang/test/CodeGenSYCL/kernel-caller-entry-point.cpp b/clang/test/CodeGenSYCL/kernel-caller-entry-point.cpp index 410988e16acdc..528d27f85e54b 100644 --- a/clang/test/CodeGenSYCL/kernel-caller-entry-point.cpp +++ b/clang/test/CodeGenSYCL/kernel-caller-entry-point.cpp @@ -148,14 +148,14 @@ int main() { // CHECK-HOST-LINUX @.str.5 = private unnamed_addr constant [30 x i8] c"_ZTS23fwd_ref_arg_kernel_name\00", align 1 // CHECK-HOST-LINUX: @.str.6 = private unnamed_addr constant [35 x i8] c"_ZTS28fwd_ref_arg_kernel_name_move\00", align 1 // CHECK-HOST-LINUX: @.str.7 = private unnamed_addr constant [33 x i8] c"_ZTS26rvalue_ref_arg_kernel_name\00", align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0CB@KFIJOMLB@_ZTS26single_purpose_kernel_name@" = linkonce_odr dso_local unnamed_addr constant [33 x i8] c"_ZTS26single_purpose_kernel_name\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0BC@NHCDOLAA@_ZTSZ4mainEUlT_E_?$AA@" = linkonce_odr dso_local unnamed_addr constant [18 x i8] c"_ZTSZ4mainEUlT_E_\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0M@BCGAEMBE@_ZTS6?N?$LE?O?$IE?O?$IH?$AA@" = linkonce_odr dso_local unnamed_addr constant [12 x i8] c"_ZTS6\CE\B4\CF\84\CF\87\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0P@DLGHPODL@_ZTSZ4mainE2KN?$AA@" = linkonce_odr dso_local unnamed_addr constant [15 x i8] c"_ZTSZ4mainE2KN\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0BK@PPDJPOBM@_ZTS19ref_arg_kernel_name?$AA@" = linkonce_odr dso_local unnamed_addr constant [26 x i8] c"_ZTS19ref_arg_kernel_name\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0BO@KEIBIHKH@_ZTS23fwd_ref_arg_kernel_name?$AA@" = linkonce_odr dso_local unnamed_addr constant [30 x i8] c"_ZTS23fwd_ref_arg_kernel_name\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0CD@FDALJLMM@_ZTS28fwd_ref_arg_kernel_name_mo@" = linkonce_odr dso_local unnamed_addr constant [35 x i8] c"_ZTS28fwd_ref_arg_kernel_name_move\00", comdat, align 1 -// CHECK-HOST-WINDOWS: @"??_C@_0CB@HCPMABHM@_ZTS26rvalue_ref_arg_kernel_name@" = linkonce_odr dso_local unnamed_addr constant [33 x i8] c"_ZTS26rvalue_ref_arg_kernel_name\00", comdat, align 1 +// CHECK-HOST-WINDOWS: @"??_C@_0CB@KFIJOMLB@_ZTS26single_purpose_kernel_name@" = linkonce_odr dso_local unnamed_addr constant [33 x i8] c"_ZTS26single_purpose_kernel_name\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0BC@NHCDOLAA@_ZTSZ4mainEUlT_E_?$AA@" = linkonce_odr dso_local unnamed_addr constant [18 x i8] c"_ZTSZ4mainEUlT_E_\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0M@BCGAEMBE@_ZTS6?N?$LE?O?$IE?O?$IH?$AA@" = linkonce_odr dso_local unnamed_addr constant [12 x i8] c"_ZTS6\CE\B4\CF\84\CF\87\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0P@DLGHPODL@_ZTSZ4mainE2KN?$AA@" = linkonce_odr dso_local unnamed_addr constant [15 x i8] c"_ZTSZ4mainE2KN\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0BK@PPDJPOBM@_ZTS19ref_arg_kernel_name?$AA@" = linkonce_odr dso_local unnamed_addr constant [26 x i8] c"_ZTS19ref_arg_kernel_name\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0BO@KEIBIHKH@_ZTS23fwd_ref_arg_kernel_name?$AA@" = linkonce_odr dso_local unnamed_addr constant [30 x i8] c"_ZTS23fwd_ref_arg_kernel_name\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0CD@FDALJLMM@_ZTS28fwd_ref_arg_kernel_name_mo@" = linkonce_odr dso_local unnamed_addr constant [35 x i8] c"_ZTS28fwd_ref_arg_kernel_name_move\00", comdat +// CHECK-HOST-WINDOWS: @"??_C@_0CB@HCPMABHM@_ZTS26rvalue_ref_arg_kernel_name@" = linkonce_odr dso_local unnamed_addr constant [33 x i8] c"_ZTS26rvalue_ref_arg_kernel_name\00", comdat // // CHECK-HOST-LINUX: define dso_local void @_Z26single_purpose_kernel_task21single_purpose_kernel() #{{[0-9]+}} { // CHECK-HOST-LINUX-NEXT: entry: >From 44e7c66cdaea9ea4fd1bb61ca90bebe74e235ac7 Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 10:52:52 +0200 Subject: [PATCH 5/7] align-x68_64.c comment --- clang/test/CodeGen/align-x68_64.c | 1 + 1 file changed, 1 insertion(+) diff --git a/clang/test/CodeGen/align-x68_64.c b/clang/test/CodeGen/align-x68_64.c index 94f967b6941d8..91f5fac199136 100644 --- a/clang/test/CodeGen/align-x68_64.c +++ b/clang/test/CodeGen/align-x68_64.c @@ -15,6 +15,7 @@ void test1_g(void) { // CHECK: @test1_g // CHECK: alloca [4 x float], align 16 +// The "large array" alignment increase does not apply on windows-msvc. // MSVC: @arr = {{.*}} align 8 // MSVC: @test1_g // MSVC: alloca [4 x float], align 4 >From 12d483afc5b8dffa2b2ec27e6fb93eee1c2ec1a6 Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 10:58:21 +0200 Subject: [PATCH 6/7] reuse microsoft-64bit-struct-align.cpp --- ...ft-struct-align.cpp => microsoft-64bit-struct-align.cpp} | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) rename clang/test/CodeGen/{arm64-microsoft-struct-align.cpp => microsoft-64bit-struct-align.cpp} (83%) diff --git a/clang/test/CodeGen/arm64-microsoft-struct-align.cpp b/clang/test/CodeGen/microsoft-64bit-struct-align.cpp similarity index 83% rename from clang/test/CodeGen/arm64-microsoft-struct-align.cpp rename to clang/test/CodeGen/microsoft-64bit-struct-align.cpp index 60bb9e2fc5405..55abcfe9910af 100644 --- a/clang/test/CodeGen/arm64-microsoft-struct-align.cpp +++ b/clang/test/CodeGen/microsoft-64bit-struct-align.cpp @@ -1,7 +1,5 @@ -// RUN: %clang_cc1 -triple aarch64-windows -ffreestanding -emit-llvm -O0 \ -// RUN: -x c++ -o - %s | FileCheck %s - -// FIXME: add tests here. +// RUN: %clang_cc1 -triple aarch64-windows-msvc -emit-llvm -o - %s | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -o - %s | FileCheck %s struct size1 { char str[1]; }; struct size2 { char str[2]; }; >From 68414eccbc6cec4de9ed062dbe2b5f26c0ea7747 Mon Sep 17 00:00:00 2001 From: Hans Wennborg <[email protected]> Date: Fri, 8 May 2026 11:24:19 +0200 Subject: [PATCH 7/7] break out Microsoft64BitMinGlobalAlign --- clang/include/clang/Basic/TargetInfo.h | 2 ++ clang/lib/Basic/TargetInfo.cpp | 17 +++++++++++++++++ clang/lib/Basic/Targets/AArch64.cpp | 13 +------------ clang/lib/Basic/Targets/X86.cpp | 14 +------------- 4 files changed, 21 insertions(+), 25 deletions(-) diff --git a/clang/include/clang/Basic/TargetInfo.h b/clang/include/clang/Basic/TargetInfo.h index 9f7d2a17a0f8a..e21155b2e4fd4 100644 --- a/clang/include/clang/Basic/TargetInfo.h +++ b/clang/include/clang/Basic/TargetInfo.h @@ -1968,6 +1968,8 @@ class TargetInfo : public TransferrableTargetInfo, void CheckFixedPointBits() const; }; +unsigned Microsoft64BitMinGlobalAlign(uint64_t TypeSize); + namespace targets { std::unique_ptr<clang::TargetInfo> AllocateTarget(const llvm::Triple &Triple, const clang::TargetOptions &Opts); diff --git a/clang/lib/Basic/TargetInfo.cpp b/clang/lib/Basic/TargetInfo.cpp index e6ae89e0948c5..d29bda889ac18 100644 --- a/clang/lib/Basic/TargetInfo.cpp +++ b/clang/lib/Basic/TargetInfo.cpp @@ -1114,3 +1114,20 @@ TargetInfo::simplifyConstraint(StringRef Constraint, } return Result; } + +unsigned clang::Microsoft64BitMinGlobalAlign(uint64_t TypeSize) { + // MSVC does size based alignment for arm64 based on alignment section in + // below document. Replicate that to keep alignment consistent with object + // files compiled by MSVC. + // https://docs.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions + // The same is done for x64, but not documented. + + if (TypeSize >= 512) // TypeSize >= 64 bytes + return 128; // align type at least 16 bytes + if (TypeSize >= 64) // TypeSize >= 8 bytes + return 64; // align type at least 8 butes + if (TypeSize >= 16) // TypeSize >= 2 bytes + return 32; // align type at least 4 bytes + + return 0; +} diff --git a/clang/lib/Basic/Targets/AArch64.cpp b/clang/lib/Basic/Targets/AArch64.cpp index 9b951e69cce33..9afe6cb10729d 100644 --- a/clang/lib/Basic/Targets/AArch64.cpp +++ b/clang/lib/Basic/Targets/AArch64.cpp @@ -1815,18 +1815,7 @@ unsigned MicrosoftARM64TargetInfo::getMinGlobalAlign(uint64_t TypeSize, unsigned Align = WindowsARM64TargetInfo::getMinGlobalAlign(TypeSize, HasNonWeakDef); - // MSVC does size based alignment for arm64 based on alignment section in - // below document, replicate that to keep alignment consistent with object - // files compiled by MSVC. - // https://docs.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions - if (TypeSize >= 512) { // TypeSize >= 64 bytes - Align = std::max(Align, 128u); // align type at least 16 bytes - } else if (TypeSize >= 64) { // TypeSize >= 8 bytes - Align = std::max(Align, 64u); // align type at least 8 butes - } else if (TypeSize >= 16) { // TypeSize >= 2 bytes - Align = std::max(Align, 32u); // align type at least 4 bytes - } - return Align; + return std::max(Align, Microsoft64BitMinGlobalAlign(TypeSize)); } MinGWARM64TargetInfo::MinGWARM64TargetInfo(const llvm::Triple &Triple, diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp index f0227be035ee3..60c001a826078 100644 --- a/clang/lib/Basic/Targets/X86.cpp +++ b/clang/lib/Basic/Targets/X86.cpp @@ -1856,20 +1856,8 @@ X86_64TargetInfo::getTargetBuiltins() const { unsigned MicrosoftX86_64TargetInfo::getMinGlobalAlign(uint64_t TypeSize, bool HasNonWeakDef) const { - // XXX: copy-pasted. can we share the code? unsigned Align = WindowsX86_64TargetInfo::getMinGlobalAlign(TypeSize, HasNonWeakDef); - // MSVC does size based alignment for arm64 based on alignment section in - // below document, replicate that to keep alignment consistent with object - // files compiled by MSVC. - // https://docs.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions - if (TypeSize >= 512) { // TypeSize >= 64 bytes - Align = std::max(Align, 128u); // align type at least 16 bytes - } else if (TypeSize >= 64) { // TypeSize >= 8 bytes - Align = std::max(Align, 64u); // align type at least 8 butes - } else if (TypeSize >= 16) { // TypeSize >= 2 bytes - Align = std::max(Align, 32u); // align type at least 4 bytes - } - return Align; + return std::max(Align, Microsoft64BitMinGlobalAlign(TypeSize)); } _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
