1 //===-- TargetOptionsImpl.cpp - Options that apply to all targets ----------==//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the methods in the TargetOptions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/Function.h"
15 #include "llvm/IR/Module.h"
16 #include "llvm/CodeGen/MachineFrameInfo.h"
17 #include "llvm/CodeGen/MachineFunction.h"
18 #include "llvm/Target/TargetFrameLowering.h"
19 #include "llvm/Target/TargetOptions.h"
20 #include "llvm/Target/TargetSubtargetInfo.h"
21 using namespace llvm;
22 
23 /// DisableFramePointerElim - This returns true if frame pointer elimination
24 /// optimization should be disabled for the given machine function.
DisableFramePointerElim(const MachineFunction & MF) const25 bool TargetOptions::DisableFramePointerElim(const MachineFunction &MF) const {
26   // Check to see if we should eliminate all frame pointers.
27   if (MF.getSubtarget().getFrameLowering()->noFramePointerElim(MF))
28     return true;
29 
30   // Check to see if we should eliminate non-leaf frame pointers.
31   if (MF.getFunction()->hasFnAttribute("no-frame-pointer-elim-non-leaf"))
32     return MF.getFrameInfo()->hasCalls();
33 
34   return false;
35 }
36 
37 /// LessPreciseFPMAD - This flag return true when -enable-fp-mad option
38 /// is specified on the command line.  When this flag is off(default), the
39 /// code generator is not allowed to generate mad (multiply add) if the
40 /// result is "less precise" than doing those operations individually.
LessPreciseFPMAD() const41 bool TargetOptions::LessPreciseFPMAD() const {
42   return UnsafeFPMath || LessPreciseFPMADOption;
43 }
44 
45 /// HonorSignDependentRoundingFPMath - Return true if the codegen must assume
46 /// that the rounding mode of the FPU can change from its default.
HonorSignDependentRoundingFPMath() const47 bool TargetOptions::HonorSignDependentRoundingFPMath() const {
48   return !UnsafeFPMath && HonorSignDependentRoundingFPMathOption;
49 }
50