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 FS) { 29 // Determine default and user-specified characteristics 30 31 if (CPUString.empty()) 32 CPUString = "generic"; 33 34 ParseSubtargetFeatures(CPUString, FS); 35 return *this; 36 } 37 38 WebAssemblySubtarget::WebAssemblySubtarget(const Triple &TT, 39 const std::string &CPU, 40 const std::string &FS, 41 const TargetMachine &TM) 42 : WebAssemblyGenSubtargetInfo(TT, CPU, FS), CPUString(CPU), 43 TargetTriple(TT), FrameLowering(), 44 InstrInfo(initializeSubtargetDependencies(FS)), TSInfo(), 45 TLInfo(TM, *this) {} 46 47 bool WebAssemblySubtarget::enableAtomicExpand() const { 48 // If atomics are disabled, atomic ops are lowered instead of expanded 49 return hasAtomics(); 50 } 51 52 bool WebAssemblySubtarget::enableMachineScheduler() const { 53 // Disable the MachineScheduler for now. Even with ShouldTrackPressure set and 54 // enableMachineSchedDefaultSched overridden, it appears to have an overall 55 // negative effect for the kinds of register optimizations we're doing. 56 return false; 57 } 58 59 bool WebAssemblySubtarget::useAA() const { return true; } 60