From: Reid Kleckner Date: Thu, 14 Dec 2017 19:00:21 +0000 (+0000) Subject: [CodeGen][X86] Implement _InterlockedCompareExchange128 intrinsic X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=512570d77f25ef18315a665a625ff2d8f502dc3b;p=clang [CodeGen][X86] Implement _InterlockedCompareExchange128 intrinsic Summary: InterlockedCompareExchange128 is a bit more complicated than the other InterlockedCompareExchange functions, so it requires a bit more work. It doesn't directly refer to 128bit ints, instead it takes pointers to 64bit ints for Destination and ComparandResult, and exchange is taken as two 64bit ints (high & low). The previous value is written to ComparandResult, and success is returned. This implementation does the following in order to produce a cmpxchg instruction: 1. Cast everything to 128bit ints or int pointers, and glues together the Exchange values 2. Reads from CompareandResult to get the comparand 3. Calls cmpxchg volatile (on X86 this will produce a lock cmpxchg16b instruction) 1. Result 0 (previous value) is written back to ComparandResult 2. Result 1 (success bool) is zext'ed to a uchar and returned Resolves bug https://llvm.org/PR35251 Patch by Colden Cullen! Reviewers: rnk, agutowski Reviewed By: rnk Subscribers: majnemer, cfe-commits Differential Revision: https://reviews.llvm.org/D41032 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320730 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/clang/Basic/BuiltinsX86_64.def b/include/clang/Basic/BuiltinsX86_64.def index 3d879386f7..fe2c887c7e 100644 --- a/include/clang/Basic/BuiltinsX86_64.def +++ b/include/clang/Basic/BuiltinsX86_64.def @@ -40,6 +40,7 @@ TARGET_HEADER_BUILTIN(_InterlockedExchangeSub64, "LLiLLiD*LLi", "nh", "intrin.h" TARGET_HEADER_BUILTIN(_InterlockedIncrement64, "LLiLLiD*", "nh", "intrin.h", ALL_MS_LANGUAGES, "") TARGET_HEADER_BUILTIN(_InterlockedOr64, "LLiLLiD*LLi", "nh", "intrin.h", ALL_MS_LANGUAGES, "") TARGET_HEADER_BUILTIN(_InterlockedXor64, "LLiLLiD*LLi", "nh", "intrin.h", ALL_MS_LANGUAGES, "") +TARGET_HEADER_BUILTIN(_InterlockedCompareExchange128, "UcLLiD*LLiLLiLLi*", "nh", "intrin.h", ALL_MS_LANGUAGES, "cx16") TARGET_BUILTIN(__builtin_ia32_readeflags_u64, "ULLi", "n", "") TARGET_BUILTIN(__builtin_ia32_writeeflags_u64, "vULLi", "n", "") diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp index 527cbf2d9d..cb052ebcac 100644 --- a/lib/CodeGen/CGBuiltin.cpp +++ b/lib/CodeGen/CGBuiltin.cpp @@ -8432,6 +8432,45 @@ Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID, return EmitMSVCBuiltinExpr(MSVCIntrin::_InterlockedDecrement, E); case X86::BI_InterlockedIncrement64: return EmitMSVCBuiltinExpr(MSVCIntrin::_InterlockedIncrement, E); + case X86::BI_InterlockedCompareExchange128: { + // InterlockedCompareExchange128 doesn't directly refer to 128bit ints, + // instead it takes pointers to 64bit ints for Destination and + // ComparandResult, and exchange is taken as two 64bit ints (high & low). + // The previous value is written to ComparandResult, and success is + // returned. + + llvm::Type *Int128Ty = Builder.getInt128Ty(); + llvm::Type *Int128PtrTy = Int128Ty->getPointerTo(); + + Value *Destination = + Builder.CreateBitCast(EmitScalarExpr(E->getArg(0)), Int128PtrTy); + Value *ExchangeHigh128 = + Builder.CreateZExt(EmitScalarExpr(E->getArg(1)), Int128Ty); + Value *ExchangeLow128 = + Builder.CreateZExt(EmitScalarExpr(E->getArg(2)), Int128Ty); + Address ComparandResult( + Builder.CreateBitCast(EmitScalarExpr(E->getArg(3)), Int128PtrTy), + getContext().toCharUnitsFromBits(128)); + + Value *Exchange = Builder.CreateOr( + Builder.CreateShl(ExchangeHigh128, 64, "", false, false), + ExchangeLow128); + + Value *Comparand = Builder.CreateLoad(ComparandResult); + + AtomicCmpXchgInst *CXI = + Builder.CreateAtomicCmpXchg(Destination, Comparand, Exchange, + AtomicOrdering::SequentiallyConsistent, + AtomicOrdering::SequentiallyConsistent); + CXI->setVolatile(true); + + // Write the result back to the inout pointer. + Builder.CreateStore(Builder.CreateExtractValue(CXI, 0), ComparandResult); + + // Get the success boolean and zero extend it to i8. + Value *Success = Builder.CreateExtractValue(CXI, 1); + return Builder.CreateZExt(Success, ConvertType(E->getType())); + } case X86::BI_AddressOfReturnAddress: { Value *F = CGM.getIntrinsic(Intrinsic::addressofreturnaddress); diff --git a/test/CodeGen/ms-intrinsics.c b/test/CodeGen/ms-intrinsics.c index 818be7fd7f..38cda97850 100644 --- a/test/CodeGen/ms-intrinsics.c +++ b/test/CodeGen/ms-intrinsics.c @@ -5,7 +5,7 @@ // RUN: -triple thumbv7--windows -Oz -emit-llvm %s -o - \ // RUN: | FileCheck %s --check-prefixes CHECK,CHECK-ARM,CHECK-ARM-X64 // RUN: %clang_cc1 -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=17.00 \ -// RUN: -triple x86_64--windows -Oz -emit-llvm %s -o - \ +// RUN: -triple x86_64--windows -Oz -emit-llvm -target-feature +cx16 %s -o - \ // RUN: | FileCheck %s --check-prefixes CHECK,CHECK-X64,CHECK-ARM-X64,CHECK-INTEL // intrin.h needs size_t, but -ffreestanding prevents us from getting it from @@ -329,6 +329,27 @@ __int64 test_InterlockedCompareExchange64(__int64 volatile *Destination, __int64 // CHECK: ret i64 [[RESULT]] // CHECK: } +#if defined(__x86_64__) +unsigned char test_InterlockedCompareExchange128(__int64 volatile *Destination, __int64 ExchangeHigh, __int64 ExchangeLow, __int64* ComparandResult) { + return _InterlockedCompareExchange128(Destination, ExchangeHigh, ExchangeLow, ComparandResult); +} +// CHECK-X64: define{{.*}}i8 @test_InterlockedCompareExchange128(i64*{{[a-z_ ]*}}%Destination, i64{{[a-z_ ]*}}%ExchangeHigh, i64{{[a-z_ ]*}}%ExchangeLow, i64*{{[a-z_ ]*}}%ComparandResult){{.*}}{ +// CHECK-X64: [[DST:%[0-9]+]] = bitcast i64* %Destination to i128* +// CHECK-X64: [[EH:%[0-9]+]] = zext i64 %ExchangeHigh to i128 +// CHECK-X64: [[EL:%[0-9]+]] = zext i64 %ExchangeLow to i128 +// CHECK-X64: [[CNR:%[0-9]+]] = bitcast i64* %ComparandResult to i128* +// CHECK-X64: [[EHS:%[0-9]+]] = shl nuw i128 [[EH]], 64 +// CHECK-X64: [[EXP:%[0-9]+]] = or i128 [[EHS]], [[EL]] +// CHECK-X64: [[ORG:%[0-9]+]] = load i128, i128* [[CNR]], align 16 +// CHECK-X64: [[RES:%[0-9]+]] = cmpxchg volatile i128* [[DST]], i128 [[ORG]], i128 [[EXP]] seq_cst seq_cst +// CHECK-X64: [[OLD:%[0-9]+]] = extractvalue { i128, i1 } [[RES]], 0 +// CHECK-X64: store i128 [[OLD]], i128* [[CNR]], align 16 +// CHECK-X64: [[SUC1:%[0-9]+]] = extractvalue { i128, i1 } [[RES]], 1 +// CHECK-X64: [[SUC8:%[0-9]+]] = zext i1 [[SUC1]] to i8 +// CHECK-X64: ret i8 [[SUC8]] +// CHECK-X64: } +#endif + short test_InterlockedIncrement16(short volatile *Addend) { return _InterlockedIncrement16(Addend); }