Added option to enable generating less precise mad (multiply addition)

for those architectures that support the instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67363 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Mon P Wang 2009-03-20 05:06:58 +00:00
parent 654c98c4f3
commit bc65ca8de5
2 changed files with 21 additions and 1 deletions

View File

@ -26,6 +26,14 @@ namespace llvm {
/// elimination optimization, this option should disable it.
extern bool NoFramePointerElim;
/// LessPreciseFPMAD - This flag is enabled when the
/// -enable-fp-mad is specified on the command line. When this flag is off
/// (the default), the code generator is not allowed to generate mad
/// (multiply add) if the result is "less precise" than doing those operations
/// individually.
extern bool LessPreciseFPMADOption;
extern bool LessPreciseFPMAD();
/// NoExcessFPPrecision - This flag is enabled when the
/// -disable-excess-fp-precision flag is specified on the command line. When
/// this flag is off (the default), the code generator is allowed to produce
@ -39,7 +47,7 @@ namespace llvm {
/// 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.
/// UnsafeFPMath implies FiniteOnlyFPMath.
/// UnsafeFPMath implies FiniteOnlyFPMath and LessPreciseFPMAD.
extern bool UnsafeFPMath;
/// FiniteOnlyFPMath - This returns true when the -enable-finite-only-fp-math

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@ -22,6 +22,7 @@ using namespace llvm;
//
namespace llvm {
bool LessPreciseFPMADOption;
bool PrintMachineCode;
bool NoFramePointerElim;
bool NoExcessFPPrecision;
@ -59,6 +60,11 @@ DisableExcessPrecision("disable-excess-fp-precision",
cl::location(NoExcessFPPrecision),
cl::init(false));
static cl::opt<bool, true>
EnableFPMAD("enable-fp-mad",
cl::desc("Enable less precise MAD instructions to be generated"),
cl::location(LessPreciseFPMADOption),
cl::init(false));
static cl::opt<bool, true>
EnableUnsafeFPMath("enable-unsafe-fp-math",
cl::desc("Enable optimizations that may decrease FP precision"),
cl::location(UnsafeFPMath),
@ -198,6 +204,12 @@ void TargetMachine::setCodeModel(CodeModel::Model Model) {
}
namespace llvm {
/// LessPreciseFPMAD - This flag return true when -enable-fp-mad option
/// is specified on the command line. When this flag is off(default), the
/// code generator is not allowed to generate mad (multiply add) if the
/// result is "less precise" than doing those operations individually.
bool LessPreciseFPMAD() { return UnsafeFPMath || LessPreciseFPMADOption; }
/// FiniteOnlyFPMath - This returns true when the -enable-finite-only-fp-math
/// option is specified on the command line. If this returns false (default),
/// the code generator is not allowed to assume that FP arithmetic arguments