[MathExtras] Favor using the hexadecimal FP constants (#123180)

This just fixes a TODO now that we are using C++17.

Author: jayfoad

llvm/include/llvm/Support/MathExtras.h

@@ -43,38 +43,37 @@ using common_sint =
 /// Mathematical constants.
 namespace numbers {
 // TODO: Track C++20 std::numbers.
-// TODO: Favor using the hexadecimal FP constants (requires C++17).
 // clang-format off
-constexpr double e          = 2.7182818284590452354, // (0x1.5bf0a8b145769P+1) https://oeis.org/A001113
-                 egamma     = .57721566490153286061, // (0x1.2788cfc6fb619P-1) https://oeis.org/A001620
-                 ln2        = .69314718055994530942, // (0x1.62e42fefa39efP-1) https://oeis.org/A002162
-                 ln10       = 2.3025850929940456840, // (0x1.26bb1bbb55516P+1) https://oeis.org/A002392
-                 log2e      = 1.4426950408889634074, // (0x1.71547652b82feP+0)
-                 log10e     = .43429448190325182765, // (0x1.bcb7b1526e50eP-2)
-                 pi         = 3.1415926535897932385, // (0x1.921fb54442d18P+1) https://oeis.org/A000796
-                 inv_pi     = .31830988618379067154, // (0x1.45f306dc9c883P-2) https://oeis.org/A049541
-                 sqrtpi     = 1.7724538509055160273, // (0x1.c5bf891b4ef6bP+0) https://oeis.org/A002161
-                 inv_sqrtpi = .56418958354775628695, // (0x1.20dd750429b6dP-1) https://oeis.org/A087197
-                 sqrt2      = 1.4142135623730950488, // (0x1.6a09e667f3bcdP+0) https://oeis.org/A00219
-                 inv_sqrt2  = .70710678118654752440, // (0x1.6a09e667f3bcdP-1)
-                 sqrt3      = 1.7320508075688772935, // (0x1.bb67ae8584caaP+0) https://oeis.org/A002194
-                 inv_sqrt3  = .57735026918962576451, // (0x1.279a74590331cP-1)
-                 phi        = 1.6180339887498948482; // (0x1.9e3779b97f4a8P+0) https://oeis.org/A001622
-constexpr float ef          = 2.71828183F, // (0x1.5bf0a8P+1) https://oeis.org/A001113
-                egammaf     = .577215665F, // (0x1.2788d0P-1) https://oeis.org/A001620
-                ln2f        = .693147181F, // (0x1.62e430P-1) https://oeis.org/A002162
-                ln10f       = 2.30258509F, // (0x1.26bb1cP+1) https://oeis.org/A002392
-                log2ef      = 1.44269504F, // (0x1.715476P+0)
-                log10ef     = .434294482F, // (0x1.bcb7b2P-2)
-                pif         = 3.14159265F, // (0x1.921fb6P+1) https://oeis.org/A000796
-                inv_pif     = .318309886F, // (0x1.45f306P-2) https://oeis.org/A049541
-                sqrtpif     = 1.77245385F, // (0x1.c5bf8aP+0) https://oeis.org/A002161
-                inv_sqrtpif = .564189584F, // (0x1.20dd76P-1) https://oeis.org/A087197
-                sqrt2f      = 1.41421356F, // (0x1.6a09e6P+0) https://oeis.org/A002193
-                inv_sqrt2f  = .707106781F, // (0x1.6a09e6P-1)
-                sqrt3f      = 1.73205081F, // (0x1.bb67aeP+0) https://oeis.org/A002194
-                inv_sqrt3f  = .577350269F, // (0x1.279a74P-1)
-                phif        = 1.61803399F; // (0x1.9e377aP+0) https://oeis.org/A001622
+constexpr double e          = 0x1.5bf0a8b145769P+1, // (2.7182818284590452354) https://oeis.org/A001113
+                 egamma     = 0x1.2788cfc6fb619P-1, // (.57721566490153286061) https://oeis.org/A001620
+                 ln2        = 0x1.62e42fefa39efP-1, // (.69314718055994530942) https://oeis.org/A002162
+                 ln10       = 0x1.26bb1bbb55516P+1, // (2.3025850929940456840) https://oeis.org/A002392
+                 log2e      = 0x1.71547652b82feP+0, // (1.4426950408889634074)
+                 log10e     = 0x1.bcb7b1526e50eP-2, // (.43429448190325182765)
+                 pi         = 0x1.921fb54442d18P+1, // (3.1415926535897932385) https://oeis.org/A000796
+                 inv_pi     = 0x1.45f306dc9c883P-2, // (.31830988618379067154) https://oeis.org/A049541
+                 sqrtpi     = 0x1.c5bf891b4ef6bP+0, // (1.7724538509055160273) https://oeis.org/A002161
+                 inv_sqrtpi = 0x1.20dd750429b6dP-1, // (.56418958354775628695) https://oeis.org/A087197
+                 sqrt2      = 0x1.6a09e667f3bcdP+0, // (1.4142135623730950488) https://oeis.org/A00219
+                 inv_sqrt2  = 0x1.6a09e667f3bcdP-1, // (.70710678118654752440)
+                 sqrt3      = 0x1.bb67ae8584caaP+0, // (1.7320508075688772935) https://oeis.org/A002194
+                 inv_sqrt3  = 0x1.279a74590331cP-1, // (.57735026918962576451)
+                 phi        = 0x1.9e3779b97f4a8P+0; // (1.6180339887498948482) https://oeis.org/A001622
+constexpr float ef          = 0x1.5bf0a8P+1F, // (2.71828183) https://oeis.org/A001113
+                egammaf     = 0x1.2788d0P-1F, // (.577215665) https://oeis.org/A001620
+                ln2f        = 0x1.62e430P-1F, // (.693147181) https://oeis.org/A002162
+                ln10f       = 0x1.26bb1cP+1F, // (2.30258509) https://oeis.org/A002392
+                log2ef      = 0x1.715476P+0F, // (1.44269504)
+                log10ef     = 0x1.bcb7b2P-2F, // (.434294482)
+                pif         = 0x1.921fb6P+1F, // (3.14159265) https://oeis.org/A000796
+                inv_pif     = 0x1.45f306P-2F, // (.318309886) https://oeis.org/A049541
+                sqrtpif     = 0x1.c5bf8aP+0F, // (1.77245385) https://oeis.org/A002161
+                inv_sqrtpif = 0x1.20dd76P-1F, // (.564189584) https://oeis.org/A087197
+                sqrt2f      = 0x1.6a09e6P+0F, // (1.41421356) https://oeis.org/A002193
+                inv_sqrt2f  = 0x1.6a09e6P-1F, // (.707106781)
+                sqrt3f      = 0x1.bb67aeP+0F, // (1.73205081) https://oeis.org/A002194
+                inv_sqrt3f  = 0x1.279a74P-1F, // (.577350269)
+                phif        = 0x1.9e377aP+0F; // (1.61803399) https://oeis.org/A001622
 // clang-format on
 } // namespace numbers