[llvm-branch-commits] [libc] [libc][math][c23] Add logf16 C23 math function (PR #106072)

[via llvm-branch-commits]

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@@ -287,6 +287,34 @@ template <bool IsSinh> LIBC_INLINE float16 eval_sinh_or_cosh(float16 x) {
       lo, half_p_odd * exp2_hi_mid_diff, half_p_even * exp2_hi_mid_sum));
 }
 
+// Generated by Sollya with the following commands:
+//   > display = hexadecimal;
+//   > for i from 0 to 31 do print(round(log(1 + i * 2^-5), SG, RN));
+constexpr cpp::array<float, 32> LOGF_F = {
+    0x0p+0f,        0x1.f829bp-6f,  0x1.f0a30cp-5f, 0x1.6f0d28p-4f,
+    0x1.e27076p-4f, 0x1.29553p-3f,  0x1.5ff308p-3f, 0x1.9525aap-3f,
+    0x1.c8ff7cp-3f, 0x1.fb9186p-3f, 0x1.1675cap-2f, 0x1.2e8e2cp-2f,
+    0x1.4618bcp-2f, 0x1.5d1bdcp-2f, 0x1.739d8p-2f,  0x1.89a338p-2f,
+    0x1.9f323ep-2f, 0x1.b44f78p-2f, 0x1.c8ff7cp-2f, 0x1.dd46ap-2f,
+    0x1.f128f6p-2f, 0x1.02552ap-1f, 0x1.0be72ep-1f, 0x1.154c3ep-1f,
+    0x1.1e85f6p-1f, 0x1.2795e2p-1f, 0x1.307d74p-1f, 0x1.393e0ep-1f,
+    0x1.41d8fep-1f, 0x1.4a4f86p-1f, 0x1.52a2d2p-1f, 0x1.5ad404p-1f,
+};
+
+// Generated by Sollya with the following commands:
+//   > display = hexadecimal;
+//   > for i from 0 to 31 do print(round(1 / (1 + i * 2^-5), SG, RN));
+constexpr cpp::array<float, 32> ONE_OVER_F = {
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overmighty wrote:

Maybe I shouldn't have used the same `ONE_OVER_F` name that common_constants.h uses for the `double` 1/f lookup table.

https://github.com/llvm/llvm-project/pull/106072