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      1 //===-- TargetOptionsImpl.cpp - Options that apply to all targets ----------==//
      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 implements the methods in the TargetOptions.
     10 //
     11 //===----------------------------------------------------------------------===//
     12 
     13 #include "llvm/CodeGen/MachineFrameInfo.h"
     14 #include "llvm/CodeGen/MachineFunction.h"
     15 #include "llvm/CodeGen/TargetFrameLowering.h"
     16 #include "llvm/CodeGen/TargetSubtargetInfo.h"
     17 #include "llvm/IR/Function.h"
     18 #include "llvm/IR/Module.h"
     19 #include "llvm/Target/TargetOptions.h"
     20 using namespace llvm;
     21 
     22 /// DisableFramePointerElim - This returns true if frame pointer elimination
     23 /// optimization should be disabled for the given machine function.
     24 bool TargetOptions::DisableFramePointerElim(const MachineFunction &MF) const {
     25   // Check to see if the target want to forcably keep frame pointer.
     26   if (MF.getSubtarget().getFrameLowering()->keepFramePointer(MF))
     27     return true;
     28 
     29   const Function &F = MF.getFunction();
     30 
     31   if (!F.hasFnAttribute("frame-pointer"))
     32     return false;
     33   StringRef FP = F.getFnAttribute("frame-pointer").getValueAsString();
     34   if (FP == "all")
     35     return true;
     36   if (FP == "non-leaf")
     37     return MF.getFrameInfo().hasCalls();
     38   if (FP == "none")
     39     return false;
     40   llvm_unreachable("unknown frame pointer flag");
     41 }
     42 
     43 /// HonorSignDependentRoundingFPMath - Return true if the codegen must assume
     44 /// that the rounding mode of the FPU can change from its default.
     45 bool TargetOptions::HonorSignDependentRoundingFPMath() const {
     46   return !UnsafeFPMath && HonorSignDependentRoundingFPMathOption;
     47 }
     48 
     49 /// NOTE: There are targets that still do not support the debug entry values
     50 /// production and that is being controlled with the SupportsDebugEntryValues.
     51 /// In addition, SCE debugger does not have the feature implemented, so prefer
     52 /// not to emit the debug entry values in that case.
     53 /// The EnableDebugEntryValues can be used for the testing purposes.
     54 bool TargetOptions::ShouldEmitDebugEntryValues() const {
     55   return (SupportsDebugEntryValues && DebuggerTuning != DebuggerKind::SCE) ||
     56          EnableDebugEntryValues;
     57 }
     58