[CodeGen][Target] Remove UnsafeFPMath uses (llvm#164549)

Remove `UnsafeFPMath` uses, next is removing the command line option.

Author: paperchalice

llvm/include/llvm/CodeGen/CommandFlags.h

@@ -58,8 +58,6 @@ LLVM_ABI CodeGenFileType getFileType();
 
 LLVM_ABI FramePointerKind getFramePointerUsage();
 
-LLVM_ABI bool getEnableUnsafeFPMath();
-
 LLVM_ABI bool getEnableNoInfsFPMath();
 
 LLVM_ABI bool getEnableNoNaNsFPMath();

llvm/include/llvm/Target/TargetOptions.h

@@ -118,9 +118,8 @@ enum CodeObjectVersionKind {
 class TargetOptions {
 public:
   TargetOptions()
-      : UnsafeFPMath(false), NoInfsFPMath(false), NoNaNsFPMath(false),
-        NoTrappingFPMath(true), NoSignedZerosFPMath(false),
-        EnableAIXExtendedAltivecABI(false),
+      : NoInfsFPMath(false), NoNaNsFPMath(false), NoTrappingFPMath(true),
+        NoSignedZerosFPMath(false), EnableAIXExtendedAltivecABI(false),
         HonorSignDependentRoundingFPMathOption(false), NoZerosInBSS(false),
         GuaranteedTailCallOpt(false), StackSymbolOrdering(true),
         EnableFastISel(false), EnableGlobalISel(false), UseInitArray(false),
@@ -156,13 +155,6 @@ class TargetOptions {
   /// MCAsmInfo::BinutilsVersion.
   std::pair<int, int> BinutilsVersion{0, 0};
 
-  /// UnsafeFPMath - This flag is enabled when the
-  /// -enable-unsafe-fp-math flag is specified on the command line.  When
-  /// this flag is off (the default), the code generator is not allowed to
-  /// produce results that are "less precise" than IEEE allows.  This includes
-  /// use of X86 instructions like FSIN and FCOS instead of libcalls.
-  unsigned UnsafeFPMath : 1;
-
   /// NoInfsFPMath - This flag is enabled when the
   /// -enable-no-infs-fp-math flag is specified on the command line. When
   /// this flag is off (the default), the code generator is not allowed to

llvm/lib/CodeGen/CommandFlags.cpp

@@ -64,7 +64,6 @@ CGOPT_EXP(uint64_t, LargeDataThreshold)
 CGOPT(ExceptionHandling, ExceptionModel)
 CGOPT_EXP(CodeGenFileType, FileType)
 CGOPT(FramePointerKind, FramePointerUsage)
-CGOPT(bool, EnableUnsafeFPMath)
 CGOPT(bool, EnableNoInfsFPMath)
 CGOPT(bool, EnableNoNaNsFPMath)
 CGOPT(bool, EnableNoSignedZerosFPMath)
@@ -219,11 +218,11 @@ codegen::RegisterCodeGenFlags::RegisterCodeGenFlags() {
                      "Enable frame pointer elimination")));
   CGBINDOPT(FramePointerUsage);
 
+  [[maybe_unused]]
   static cl::opt<bool> EnableUnsafeFPMath(
       "enable-unsafe-fp-math",
       cl::desc("Enable optimizations that may decrease FP precision"),
       cl::init(false));
-  CGBINDOPT(EnableUnsafeFPMath);
 
   static cl::opt<bool> EnableNoInfsFPMath(
       "enable-no-infs-fp-math",
@@ -552,7 +551,6 @@ TargetOptions
 codegen::InitTargetOptionsFromCodeGenFlags(const Triple &TheTriple) {
   TargetOptions Options;
   Options.AllowFPOpFusion = getFuseFPOps();
-  Options.UnsafeFPMath = getEnableUnsafeFPMath();
   Options.NoInfsFPMath = getEnableNoInfsFPMath();
   Options.NoNaNsFPMath = getEnableNoNaNsFPMath();
   Options.NoSignedZerosFPMath = getEnableNoSignedZerosFPMath();
@@ -706,7 +704,6 @@ void codegen::setFunctionAttributes(StringRef CPU, StringRef Features,
   if (getStackRealign())
     NewAttrs.addAttribute("stackrealign");
 
-  HANDLE_BOOL_ATTR(EnableUnsafeFPMathView, "unsafe-fp-math");
   HANDLE_BOOL_ATTR(EnableNoInfsFPMathView, "no-infs-fp-math");
   HANDLE_BOOL_ATTR(EnableNoNaNsFPMathView, "no-nans-fp-math");
   HANDLE_BOOL_ATTR(EnableNoSignedZerosFPMathView, "no-signed-zeros-fp-math");

llvm/lib/CodeGen/TargetOptionsImpl.cpp

@@ -51,7 +51,7 @@ bool TargetOptions::FramePointerIsReserved(const MachineFunction &MF) const {
 /// HonorSignDependentRoundingFPMath - Return true if the codegen must assume
 /// that the rounding mode of the FPU can change from its default.
 bool TargetOptions::HonorSignDependentRoundingFPMath() const {
-  return !UnsafeFPMath && HonorSignDependentRoundingFPMathOption;
+  return HonorSignDependentRoundingFPMathOption;
 }
 
 /// NOTE: There are targets that still do not support the debug entry values

llvm/lib/Target/TargetMachine.cpp

@@ -158,7 +158,6 @@ void TargetMachine::resetTargetOptions(const Function &F) const {
     Options.X = F.getFnAttribute(Y).getValueAsBool();     \
   } while (0)
 
-  RESET_OPTION(UnsafeFPMath, "unsafe-fp-math");
   RESET_OPTION(NoInfsFPMath, "no-infs-fp-math");
   RESET_OPTION(NoNaNsFPMath, "no-nans-fp-math");
   RESET_OPTION(NoSignedZerosFPMath, "no-signed-zeros-fp-math");