1 //===- SPIRVTargetTransformInfo.h - SPIR-V specific TTI ---------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // \file 9 // This file contains a TargetTransformInfo::Concept conforming object specific 10 // to the SPIRV target machine. It uses the target's detailed information to 11 // provide more precise answers to certain TTI queries, while letting the 12 // target independent and default TTI implementations handle the rest. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_LIB_TARGET_SPIRV_SPIRVTARGETTRANSFORMINFO_H 17 #define LLVM_LIB_TARGET_SPIRV_SPIRVTARGETTRANSFORMINFO_H 18 19 #include "SPIRV.h" 20 #include "SPIRVTargetMachine.h" 21 #include "llvm/Analysis/TargetTransformInfo.h" 22 #include "llvm/CodeGen/BasicTTIImpl.h" 23 24 namespace llvm { 25 class SPIRVTTIImpl : public BasicTTIImplBase<SPIRVTTIImpl> { 26 using BaseT = BasicTTIImplBase<SPIRVTTIImpl>; 27 using TTI = TargetTransformInfo; 28 29 friend BaseT; 30 31 const SPIRVSubtarget *ST; 32 const SPIRVTargetLowering *TLI; 33 34 const TargetSubtargetInfo *getST() const { return ST; } 35 const SPIRVTargetLowering *getTLI() const { return TLI; } 36 37 public: 38 explicit SPIRVTTIImpl(const SPIRVTargetMachine *TM, const Function &F) 39 : BaseT(TM, F.getDataLayout()), ST(TM->getSubtargetImpl(F)), 40 TLI(ST->getTargetLowering()) {} 41 42 TTI::PopcntSupportKind getPopcntSupport(unsigned TyWidth) { 43 // SPIR-V natively supports OpBitcount, per 3.53.14 in the spec, as such it 44 // is reasonable to assume the Op is fast / preferable to the expanded loop. 45 // Furthermore, this prevents information being lost if transforms are 46 // applied to SPIR-V before lowering to a concrete target. 47 if (!isPowerOf2_32(TyWidth) || TyWidth > 64) 48 return TTI::PSK_Software; // Arbitrary bit-width INT is not core SPIR-V. 49 return TTI::PSK_FastHardware; 50 } 51 }; 52 53 } // namespace llvm 54 55 #endif // LLVM_LIB_TARGET_SPIRV_SPIRVTARGETTRANSFORMINFO_H 56