From: Hans Wennborg Date: Wed, 19 Jun 2019 11:34:08 +0000 (+0000) Subject: Revert r363116 "[X86] [ABI] Fix i386 ABI "__m64" type bug" X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7a5dd209e33cb6330a14bb5a076efd347c106218;p=clang Revert r363116 "[X86] [ABI] Fix i386 ABI "__m64" type bug" This introduced MMX instructions in code that wasn't previously using them, breaking programs using 64-bit vectors and x87 floating-point in the same application. See discussion on the code review for more details. > According to System V i386 ABI: the __m64 type paramater and return > value are passed by MMX registers. But current implementation treats > __m64 as i64 which results in parameter passing by stack and returning > by EDX and EAX. > > This patch fixes the bug (https://bugs.llvm.org/show_bug.cgi?id=41029) > for Linux and NetBSD. > > Patch by Wei Xiao (wxiao3) > > Differential Revision: https://reviews.llvm.org/D59744 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@363790 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp index b1ff46049f..9a991825dd 100644 --- a/lib/CodeGen/TargetInfo.cpp +++ b/lib/CodeGen/TargetInfo.cpp @@ -915,6 +915,14 @@ ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const { : ABIArgInfo::getDirect()); } +/// IsX86_MMXType - Return true if this is an MMX type. +bool IsX86_MMXType(llvm::Type *IRType) { + // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>. + return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 && + cast(IRType)->getElementType()->isIntegerTy() && + IRType->getScalarSizeInBits() != 64; +} + static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF, StringRef Constraint, llvm::Type* Ty) { @@ -1003,7 +1011,6 @@ class X86_32ABIInfo : public SwiftABIInfo { bool IsSoftFloatABI; bool IsMCUABI; unsigned DefaultNumRegisterParameters; - bool IsMMXEnabled; static bool isRegisterSize(unsigned Size) { return (Size == 8 || Size == 16 || Size == 32 || Size == 64); @@ -1063,15 +1070,13 @@ public: X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI, bool RetSmallStructInRegABI, bool Win32StructABI, - unsigned NumRegisterParameters, bool SoftFloatABI, - bool MMXEnabled) + unsigned NumRegisterParameters, bool SoftFloatABI) : SwiftABIInfo(CGT), IsDarwinVectorABI(DarwinVectorABI), IsRetSmallStructInRegABI(RetSmallStructInRegABI), IsWin32StructABI(Win32StructABI), IsSoftFloatABI(SoftFloatABI), IsMCUABI(CGT.getTarget().getTriple().isOSIAMCU()), - DefaultNumRegisterParameters(NumRegisterParameters), - IsMMXEnabled(MMXEnabled) {} + DefaultNumRegisterParameters(NumRegisterParameters) {} bool shouldPassIndirectlyForSwift(ArrayRef scalars, bool asReturnValue) const override { @@ -1086,30 +1091,16 @@ public: // x86-32 lowering does not support passing swifterror in a register. return false; } - - bool isPassInMMXRegABI() const { - // The System V i386 psABI requires __m64 to be passed in MMX registers. - // Clang historically had a bug where it failed to apply this rule, and - // some platforms (e.g. Darwin, PS4, and FreeBSD) have opted to maintain - // compatibility with the old Clang behavior, so we only apply it on - // platforms that have specifically requested it (currently just Linux and - // NetBSD). - const llvm::Triple &T = getTarget().getTriple(); - if (IsMMXEnabled && (T.isOSLinux() || T.isOSNetBSD())) - return true; - return false; - } }; class X86_32TargetCodeGenInfo : public TargetCodeGenInfo { public: X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI, bool RetSmallStructInRegABI, bool Win32StructABI, - unsigned NumRegisterParameters, bool SoftFloatABI, - bool MMXEnabled = false) + unsigned NumRegisterParameters, bool SoftFloatABI) : TargetCodeGenInfo(new X86_32ABIInfo( CGT, DarwinVectorABI, RetSmallStructInRegABI, Win32StructABI, - NumRegisterParameters, SoftFloatABI, MMXEnabled)) {} + NumRegisterParameters, SoftFloatABI)) {} static bool isStructReturnInRegABI( const llvm::Triple &Triple, const CodeGenOptions &Opts); @@ -1395,9 +1386,10 @@ ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy, } if (const VectorType *VT = RetTy->getAs()) { - uint64_t Size = getContext().getTypeSize(RetTy); // On Darwin, some vectors are returned in registers. if (IsDarwinVectorABI) { + uint64_t Size = getContext().getTypeSize(RetTy); + // 128-bit vectors are a special case; they are returned in // registers and we need to make sure to pick a type the LLVM // backend will like. @@ -1415,10 +1407,6 @@ ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy, return getIndirectReturnResult(RetTy, State); } - if (VT->getElementType()->isIntegerType() && Size == 64 && - isPassInMMXRegABI()) - return ABIArgInfo::getDirect(llvm::Type::getX86_MMXTy(getVMContext())); - return ABIArgInfo::getDirect(); } @@ -1713,26 +1701,23 @@ ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty, } if (const VectorType *VT = Ty->getAs()) { - uint64_t Size = getContext().getTypeSize(Ty); // On Darwin, some vectors are passed in memory, we handle this by passing // it as an i8/i16/i32/i64. if (IsDarwinVectorABI) { + uint64_t Size = getContext().getTypeSize(Ty); if ((Size == 8 || Size == 16 || Size == 32) || (Size == 64 && VT->getNumElements() == 1)) return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size)); } - if (VT->getElementType()->isIntegerType() && Size == 64) { - if (isPassInMMXRegABI()) - return ABIArgInfo::getDirect(llvm::Type::getX86_MMXTy(getVMContext())); - else - return ABIArgInfo::getDirect( - llvm::IntegerType::get(getVMContext(), 64)); - } + if (IsX86_MMXType(CGT.ConvertType(Ty))) + return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64)); + return ABIArgInfo::getDirect(); } + if (const EnumType *EnumTy = Ty->getAs()) Ty = EnumTy->getDecl()->getIntegerType(); @@ -9508,11 +9493,10 @@ const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() { Types, IsDarwinVectorABI, RetSmallStructInRegABI, IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters)); } else { - bool EnableMMX = getContext().getTargetInfo().getABI() != "no-mmx"; return SetCGInfo(new X86_32TargetCodeGenInfo( Types, IsDarwinVectorABI, RetSmallStructInRegABI, IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters, - CodeGenOpts.FloatABI == "soft", EnableMMX)); + CodeGenOpts.FloatABI == "soft")); } } diff --git a/test/CodeGen/x86_32-arguments-linux.c b/test/CodeGen/x86_32-arguments-linux.c index 1bdaa628eb..3c64fbcc15 100644 --- a/test/CodeGen/x86_32-arguments-linux.c +++ b/test/CodeGen/x86_32-arguments-linux.c @@ -3,7 +3,7 @@ // CHECK-LABEL: define void @f56( // CHECK: i8 signext %a0, %struct.s56_0* byval(%struct.s56_0) align 4 %a1, -// CHECK: x86_mmx %a2.coerce, %struct.s56_1* byval(%struct.s56_1) align 4, +// CHECK: i64 %a2.coerce, %struct.s56_1* byval(%struct.s56_1) align 4, // CHECK: <1 x double> %a4, %struct.s56_2* byval(%struct.s56_2) align 4, // CHECK: <4 x i32> %a6, %struct.s56_3* byval(%struct.s56_3) align 4, // CHECK: <2 x double> %a8, %struct.s56_4* byval(%struct.s56_4) align 4, @@ -12,7 +12,7 @@ // CHECK: call void (i32, ...) @f56_0(i32 1, // CHECK: i32 %{{.*}}, %struct.s56_0* byval(%struct.s56_0) align 4 %{{[^ ]*}}, -// CHECK: x86_mmx %{{[^ ]*}}, %struct.s56_1* byval(%struct.s56_1) align 4 %{{[^ ]*}}, +// CHECK: i64 %{{[^ ]*}}, %struct.s56_1* byval(%struct.s56_1) align 4 %{{[^ ]*}}, // CHECK: <1 x double> %{{[^ ]*}}, %struct.s56_2* byval(%struct.s56_2) align 4 %{{[^ ]*}}, // CHECK: <4 x i32> %{{[^ ]*}}, %struct.s56_3* byval(%struct.s56_3) align 4 %{{[^ ]*}}, // CHECK: <2 x double> %{{[^ ]*}}, %struct.s56_4* byval(%struct.s56_4) align 4 %{{[^ ]*}}, diff --git a/test/CodeGen/x86_32-m64.c b/test/CodeGen/x86_32-m64.c deleted file mode 100644 index 2be09fa17b..0000000000 --- a/test/CodeGen/x86_32-m64.c +++ /dev/null @@ -1,29 +0,0 @@ -// RUN: %clang_cc1 -w -O2 -fblocks -triple i386-pc-linux-gnu -target-cpu pentium4 -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,LINUX -// RUN: %clang_cc1 -w -O2 -fblocks -triple i386-netbsd -target-cpu pentium4 -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,NETBSD -// RUN: %clang_cc1 -w -O2 -fblocks -triple i386-apple-darwin9 -target-cpu yonah -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,DARWIN -// RUN: %clang_cc1 -w -O2 -fblocks -triple i386-pc-elfiamcu -mfloat-abi soft -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,IAMCU -// RUN: %clang_cc1 -w -O2 -fblocks -triple i386-pc-win32 -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,WIN32 - -#include -__m64 m64; -void callee(__m64 __m1, __m64 __m2); -__m64 caller(__m64 __m1, __m64 __m2) -{ -// LINUX-LABEL: define x86_mmx @caller(x86_mmx %__m1.coerce, x86_mmx %__m2.coerce) -// LINUX: tail call void @callee(x86_mmx %__m2.coerce, x86_mmx %__m1.coerce) -// LINUX: ret x86_mmx -// NETBSD-LABEL: define x86_mmx @caller(x86_mmx %__m1.coerce, x86_mmx %__m2.coerce) -// NETBSD: tail call void @callee(x86_mmx %__m2.coerce, x86_mmx %__m1.coerce) -// NETBSD: ret x86_mmx -// DARWIN-LABEL: define i64 @caller(i64 %__m1.coerce, i64 %__m2.coerce) -// DARWIN: tail call void @callee(i64 %__m2.coerce, i64 %__m1.coerce) -// DARWIN: ret i64 -// IAMCU-LABEL: define <1 x i64> @caller(i64 %__m1.coerce, i64 %__m2.coerce) -// IAMCU: tail call void @callee(i64 %__m2.coerce, i64 %__m1.coerce) -// IAMCU: ret <1 x i64> -// WIN32-LABEL: define dso_local <1 x i64> @caller(i64 %__m1.coerce, i64 %__m2.coerce) -// WIN32: call void @callee(i64 %__m2.coerce, i64 %__m1.coerce) -// WIN32: ret <1 x i64> - callee(__m2, __m1); - return m64; -}