1 //===-- WebAssemblySubtarget.cpp - WebAssembly Subtarget Information ------===// 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 /// 9 /// \file 10 /// This file implements the WebAssembly-specific subclass of 11 /// TargetSubtarget. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #include "WebAssemblySubtarget.h" 16 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h" 17 #include "WebAssemblyInstrInfo.h" 18 #include "llvm/Support/TargetRegistry.h" 19 using namespace llvm; 20 21 #define DEBUG_TYPE "wasm-subtarget" 22 23 #define GET_SUBTARGETINFO_CTOR 24 #define GET_SUBTARGETINFO_TARGET_DESC 25 #include "WebAssemblyGenSubtargetInfo.inc" 26 27 WebAssemblySubtarget & 28 WebAssemblySubtarget::initializeSubtargetDependencies(StringRef CPU, 29 StringRef FS) { 30 // Determine default and user-specified characteristics 31 LLVM_DEBUG(llvm::dbgs() << "initializeSubtargetDependencies\n"); 32 33 if (CPU.empty()) 34 CPU = "generic"; 35 36 ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS); 37 return *this; 38 } 39 40 WebAssemblySubtarget::WebAssemblySubtarget(const Triple &TT, 41 const std::string &CPU, 42 const std::string &FS, 43 const TargetMachine &TM) 44 : WebAssemblyGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS), 45 TargetTriple(TT), FrameLowering(), 46 InstrInfo(initializeSubtargetDependencies(CPU, FS)), TSInfo(), 47 TLInfo(TM, *this) {} 48 49 bool WebAssemblySubtarget::enableAtomicExpand() const { 50 // If atomics are disabled, atomic ops are lowered instead of expanded 51 return hasAtomics(); 52 } 53 54 bool WebAssemblySubtarget::enableMachineScheduler() const { 55 // Disable the MachineScheduler for now. Even with ShouldTrackPressure set and 56 // enableMachineSchedDefaultSched overridden, it appears to have an overall 57 // negative effect for the kinds of register optimizations we're doing. 58 return false; 59 } 60 61 bool WebAssemblySubtarget::useAA() const { return true; } 62