[AMDGPU] Use math constants defined in MathExtras (NFC)

Use the the new math constants in `MathExtras.h`.

Differential revision: https://reviews.llvm.org/D68285

llvm-svn: 374208

llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp

@@ -12,10 +12,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define AMDGPU_LOG2E_F     1.44269504088896340735992468100189214f
-#define AMDGPU_LN2_F       0.693147180559945309417232121458176568f
-#define AMDGPU_LN10_F      2.30258509299404568401799145468436421f
-
 #include "AMDGPUISelLowering.h"
 #include "AMDGPU.h"
 #include "AMDGPUCallLowering.h"
@@ -37,6 +33,7 @@
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/Support/KnownBits.h"
+#include "llvm/Support/MathExtras.h"
 using namespace llvm;
 
 #include "AMDGPUGenCallingConv.inc"
@@ -1135,9 +1132,9 @@ SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
   case ISD::FROUND: return LowerFROUND(Op, DAG);
   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
   case ISD::FLOG:
-    return LowerFLOG(Op, DAG, 1 / AMDGPU_LOG2E_F);
+    return LowerFLOG(Op, DAG, 1.0F / numbers::log2ef);
   case ISD::FLOG10:
-    return LowerFLOG(Op, DAG, AMDGPU_LN2_F / AMDGPU_LN10_F);
+    return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
   case ISD::FEXP:
     return lowerFEXP(Op, DAG);
   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
@@ -2285,30 +2282,13 @@ SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
 }
 
-// Return M_LOG2E of appropriate type
-static SDValue getLog2EVal(SelectionDAG &DAG, const SDLoc &SL, EVT VT) {
-  switch (VT.getScalarType().getSimpleVT().SimpleTy) {
-  case MVT::f32:
-    return DAG.getConstantFP(1.44269504088896340735992468100189214f, SL, VT);
-  case MVT::f16:
-    return DAG.getConstantFP(
-      APFloat(APFloat::IEEEhalf(), "1.44269504088896340735992468100189214"),
-      SL, VT);
-  case MVT::f64:
-    return DAG.getConstantFP(
-      APFloat(APFloat::IEEEdouble(), "0x1.71547652b82fep+0"), SL, VT);
-  default:
-    llvm_unreachable("unsupported fp type");
-  }
-}
-
 // exp2(M_LOG2E_F * f);
 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
   EVT VT = Op.getValueType();
   SDLoc SL(Op);
   SDValue Src = Op.getOperand(0);
 
-  const SDValue K = getLog2EVal(DAG, SL, VT);
+  const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
 }

llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp

@@ -30,6 +30,7 @@
 #include "llvm/IR/Module.h"
 #include "llvm/IR/ValueSymbolTable.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"
@@ -48,18 +49,10 @@ static cl::list<std::string> UseNative("amdgpu-use-native",
   cl::CommaSeparated, cl::ValueOptional,
   cl::Hidden);
 
-#define MATH_PI     3.14159265358979323846264338327950288419716939937511
-#define MATH_E      2.71828182845904523536028747135266249775724709369996
-#define MATH_SQRT2  1.41421356237309504880168872420969807856967187537695
-
-#define MATH_LOG2E     1.4426950408889634073599246810018921374266459541529859
-#define MATH_LOG10E    0.4342944819032518276511289189166050822943970058036665
-// Value of log2(10)
-#define MATH_LOG2_10   3.3219280948873623478703194294893901758648313930245806
-// Value of 1 / log2(10)
-#define MATH_RLOG2_10  0.3010299956639811952137388947244930267681898814621085
-// Value of 1 / M_LOG2E_F = 1 / log2(e)
-#define MATH_RLOG2_E   0.6931471805599453094172321214581765680755001343602552
+#define MATH_PI      numbers::pi
+#define MATH_E       numbers::e
+#define MATH_SQRT2   numbers::sqrt2
+#define MATH_SQRT1_2 numbers::inv_sqrt2
 
 namespace llvm {
 
@@ -254,8 +247,8 @@ struct TableEntry {
 
 /* a list of {result, input} */
 static const TableEntry tbl_acos[] = {
-  {MATH_PI/2.0, 0.0},
-  {MATH_PI/2.0, -0.0},
+  {MATH_PI / 2.0, 0.0},
+  {MATH_PI / 2.0, -0.0},
   {0.0, 1.0},
   {MATH_PI, -1.0}
 };
@@ -271,8 +264,8 @@ static const TableEntry tbl_acospi[] = {
 static const TableEntry tbl_asin[] = {
   {0.0, 0.0},
   {-0.0, -0.0},
-  {MATH_PI/2.0, 1.0},
-  {-MATH_PI/2.0, -1.0}
+  {MATH_PI / 2.0, 1.0},
+  {-MATH_PI / 2.0, -1.0}
 };
 static const TableEntry tbl_asinh[] = {
   {0.0, 0.0},
@@ -287,8 +280,8 @@ static const TableEntry tbl_asinpi[] = {
 static const TableEntry tbl_atan[] = {
   {0.0, 0.0},
   {-0.0, -0.0},
-  {MATH_PI/4.0, 1.0},
-  {-MATH_PI/4.0, -1.0}
+  {MATH_PI / 4.0, 1.0},
+  {-MATH_PI / 4.0, -1.0}
 };
 static const TableEntry tbl_atanh[] = {
   {0.0, 0.0},
@@ -359,7 +352,7 @@ static const TableEntry tbl_log10[] = {
 };
 static const TableEntry tbl_rsqrt[] = {
   {1.0, 1.0},
-  {1.0/MATH_SQRT2, 2.0}
+  {MATH_SQRT1_2, 2.0}
 };
 static const TableEntry tbl_sin[] = {
   {0.0, 0.0},
@@ -868,7 +861,7 @@ static double log2(double V) {
 #if _XOPEN_SOURCE >= 600 || defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
   return ::log2(V);
 #else
-  return log(V) / 0.693147180559945309417;
+  return log(V) / numbers::ln2;
 #endif
 }
 }

llvm/lib/Target/AMDGPU/R600ISelLowering.cpp

@@ -41,6 +41,7 @@
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MachineValueType.h"
+#include "llvm/Support/MathExtras.h"
 #include <cassert>
 #include <cstdint>
 #include <iterator>
@@ -782,7 +783,7 @@ SDValue R600TargetLowering::LowerTrig(SDValue Op, SelectionDAG &DAG) const {
     return TrigVal;
   // On R600 hw, COS/SIN input must be between -Pi and Pi.
   return DAG.getNode(ISD::FMUL, DL, VT, TrigVal,
-      DAG.getConstantFP(3.14159265359, DL, MVT::f32));
+      DAG.getConstantFP(numbers::pif, DL, MVT::f32));
 }
 
 SDValue R600TargetLowering::LowerSHLParts(SDValue Op, SelectionDAG &DAG) const {