prefix utilities with exp10

Author: bassiounix

libc/src/__support/math/exp10.h

@@ -36,20 +36,20 @@ using Float128 = typename fputil::DyadicFloat<128>;
 using LIBC_NAMESPACE::operator""_u128;
 
 // log2(10)
-constexpr double LOG2_10 = 0x1.a934f0979a371p+1;
+static constexpr double LOG2_10 = 0x1.a934f0979a371p+1;
 
 // -2^-12 * log10(2)
 // > a = -2^-12 * log10(2);
 // > b = round(a, 32, RN);
 // > c = round(a - b, 32, RN);
 // > d = round(a - b - c, D, RN);
 // Errors < 1.5 * 2^-144
-constexpr double MLOG10_2_EXP2_M12_HI = -0x1.3441350ap-14;
-constexpr double MLOG10_2_EXP2_M12_MID = 0x1.0c0219dc1da99p-51;
+static constexpr double MLOG10_2_EXP2_M12_HI = -0x1.3441350ap-14;
+static constexpr double MLOG10_2_EXP2_M12_MID = 0x1.0c0219dc1da99p-51;
 
 #ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-constexpr double MLOG10_2_EXP2_M12_MID_32 = 0x1.0c0219dcp-51;
-constexpr double MLOG10_2_EXP2_M12_LO = 0x1.da994fd20dba2p-87;
+static constexpr double MLOG10_2_EXP2_M12_MID_32 = 0x1.0c0219dcp-51;
+static constexpr double MLOG10_2_EXP2_M12_LO = 0x1.da994fd20dba2p-87;
 #endif // LIBC_MATH_HAS_SKIP_ACCURATE_PASS
 
 // Error bounds:
@@ -58,17 +58,15 @@ constexpr double ERR_D = 0x1.8p-63;
 
 #ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
 // Errors when using double-double precision.
-constexpr double ERR_DD = 0x1.8p-99;
+static constexpr double ERR_DD = 0x1.8p-99;
 #endif // LIBC_MATH_HAS_SKIP_ACCURATE_PASS
 
-namespace {
-
 // Polynomial approximations with double precision.  Generated by Sollya with:
 // > P = fpminimax((10^x - 1)/x, 3, [|D...|], [-2^-14, 2^-14]);
 // > P;
 // Error bounds:
 //   | output - (10^dx - 1) / dx | < 2^-52.
-LIBC_INLINE static double poly_approx_d(double dx) {
+LIBC_INLINE static double exp10_poly_approx_d(double dx) {
   // dx^2
   double dx2 = dx * dx;
   double c0 =
@@ -85,7 +83,7 @@ LIBC_INLINE static double poly_approx_d(double dx) {
 // > P = fpminimax((10^x - 1)/x, 5, [|DD...|], [-2^-14, 2^-14]);
 // Error bounds:
 //   | output - 10^(dx) | < 2^-101
-static constexpr DoubleDouble poly_approx_dd(const DoubleDouble &dx) {
+static constexpr DoubleDouble exp10_poly_approx_dd(const DoubleDouble &dx) {
   // Taylor polynomial.
   constexpr DoubleDouble COEFFS[] = {
       {0, 0x1p0},
@@ -107,7 +105,7 @@ static constexpr DoubleDouble poly_approx_dd(const DoubleDouble &dx) {
 // Return exp(dx) ~ 1 + a0 * dx + a1 * dx^2 + ... + a6 * dx^7
 // For |dx| < 2^-14:
 //   | output - 10^dx | < 1.5 * 2^-124.
-static constexpr Float128 poly_approx_f128(const Float128 &dx) {
+static constexpr Float128 exp10_poly_approx_f128(const Float128 &dx) {
   constexpr Float128 COEFFS_128[]{
       {Sign::POS, -127, 0x80000000'00000000'00000000'00000000_u128}, // 1.0
       {Sign::POS, -126, 0x935d8ddd'aaa8ac16'ea56d62b'82d30a2d_u128},
@@ -149,7 +147,7 @@ static Float128 exp10_f128(double x, double kd, int idx1, int idx2) {
 
   Float128 exp_mid = fputil::quick_mul(exp_mid1, exp_mid2);
 
-  Float128 p = poly_approx_f128(dx);
+  Float128 p = exp10_poly_approx_f128(dx);
 
   Float128 r = fputil::quick_mul(exp_mid, p);
 
@@ -172,7 +170,7 @@ static DoubleDouble exp10_double_double(double x, double kd,
 
   // Degree-6 polynomial approximation in double-double precision.
   // | p - 10^x | < 2^-103.
-  DoubleDouble p = poly_approx_dd(dx);
+  DoubleDouble p = exp10_poly_approx_dd(dx);
 
   // Error bounds: 2^-102.
   DoubleDouble r = fputil::quick_mult(exp_mid, p);
@@ -204,7 +202,7 @@ static double exp10_denorm(double x) {
   double mid_lo = dx * exp_mid.hi;
 
   // Approximate (10^dx - 1)/dx ~ 1 + a0*dx + a1*dx^2 + a2*dx^3 + a3*dx^4.
-  double p = poly_approx_d(dx);
+  double p = exp10_poly_approx_d(dx);
 
   double lo = fputil::multiply_add(p, mid_lo, exp_mid.lo);
 
@@ -235,7 +233,7 @@ static double exp10_denorm(double x) {
 //  * x >= log10(2^1024)
 //  * x <= log10(2^-1022)
 //  * x is inf or nan
-static constexpr double set_exceptional(double x) {
+static constexpr double exp10_set_exceptional(double x) {
   using FPBits = typename fputil::FPBits<double>;
   FPBits xbits(x);
 
@@ -284,8 +282,6 @@ static constexpr double set_exceptional(double x) {
   return x + FPBits::inf().get_val();
 }
 
-} // namespace
-
 namespace math {
 
 static constexpr double exp10(double x) {
@@ -299,7 +295,7 @@ static constexpr double exp10(double x) {
   if (LIBC_UNLIKELY(x_u >= 0xc0733a7146f72a42 ||
                     (x_u <= 0xbc7bcb7b1526e50e && x_u >= 0x40734413509f79ff) ||
                     x_u < 0x3c8bcb7b1526e50e)) {
-    return set_exceptional(x);
+    return exp10_set_exceptional(x);
   }
 
   // Now log10(2^-1075) < x <= log10(1 - 2^-54) or
@@ -403,7 +399,7 @@ static constexpr double exp10(double x) {
   double mid_lo = dx * exp_mid.hi;
 
   // Approximate (10^dx - 1)/dx ~ 1 + a0*dx + a1*dx^2 + a2*dx^3 + a3*dx^4.
-  double p = poly_approx_d(dx);
+  double p = exp10_poly_approx_d(dx);
 
   double lo = fputil::multiply_add(p, mid_lo, exp_mid.lo);