llvm/lib/Target/RISCV/RISCVMachineFunctionInfo.cpp

   1 //=- RISCVMachineFunctionInfo.cpp - RISC-V machine function info --*- 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 //
   9 // This file declares RISCV-specific per-machine-function information.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "RISCVMachineFunctionInfo.h"
  14 #include "llvm/IR/Module.h"
  15
  16 using namespace llvm;
  17
  18 yaml::RISCVMachineFunctionInfo::RISCVMachineFunctionInfo(
  19     const llvm::RISCVMachineFunctionInfo &MFI)
  20     : VarArgsFrameIndex(MFI.getVarArgsFrameIndex()),
  21       VarArgsSaveSize(MFI.getVarArgsSaveSize()) {}
  22
  23 MachineFunctionInfo *RISCVMachineFunctionInfo::clone(
  24     BumpPtrAllocator &Allocator, MachineFunction &DestMF,
  25     const DenseMap<MachineBasicBlock *, MachineBasicBlock *> &Src2DstMBB)
  26     const {
  27   return DestMF.cloneInfo<RISCVMachineFunctionInfo>(*this);
  28 }
  29
  30 RISCVMachineFunctionInfo::RISCVMachineFunctionInfo(const Function &F,
  31                                                    const RISCVSubtarget *STI) {
  32
  33   // The default stack probe size is 4096 if the function has no
  34   // stack-probe-size attribute. This is a safe default because it is the
  35   // smallest possible guard page size.
  36   uint64_t ProbeSize = 4096;
  37   if (F.hasFnAttribute("stack-probe-size"))
  38     ProbeSize = F.getFnAttributeAsParsedInteger("stack-probe-size");
  39   else if (const auto *PS = mdconst::extract_or_null<ConstantInt>(
  40                F.getParent()->getModuleFlag("stack-probe-size")))
  41     ProbeSize = PS->getZExtValue();
  42   assert(int64_t(ProbeSize) > 0 && "Invalid stack probe size");
  43
  44   // Round down to the stack alignment.
  45   uint64_t StackAlign =
  46       STI->getFrameLowering()->getTransientStackAlign().value();
  47   ProbeSize = std::max(StackAlign, alignDown(ProbeSize, StackAlign));
  48   StringRef ProbeKind;
  49   if (F.hasFnAttribute("probe-stack"))
  50     ProbeKind = F.getFnAttribute("probe-stack").getValueAsString();
  51   else if (const auto *PS = dyn_cast_or_null<MDString>(
  52                F.getParent()->getModuleFlag("probe-stack")))
  53     ProbeKind = PS->getString();
  54   if (ProbeKind.size()) {
  55     StackProbeSize = ProbeSize;
  56   }
  57 }
  58
  59 void yaml::RISCVMachineFunctionInfo::mappingImpl(yaml::IO &YamlIO) {
  60   MappingTraits<RISCVMachineFunctionInfo>::mapping(YamlIO, *this);
  61 }
  62
  63 void RISCVMachineFunctionInfo::initializeBaseYamlFields(
  64     const yaml::RISCVMachineFunctionInfo &YamlMFI) {
  65   VarArgsFrameIndex = YamlMFI.VarArgsFrameIndex;
  66   VarArgsSaveSize = YamlMFI.VarArgsSaveSize;
  67 }
  68
  69 void RISCVMachineFunctionInfo::addSExt32Register(Register Reg) {
  70   SExt32Registers.push_back(Reg);
  71 }
  72
  73 bool RISCVMachineFunctionInfo::isSExt32Register(Register Reg) const {
  74   return is_contained(SExt32Registers, Reg);
  75 }