[libc-commits] [libc] [libc][math] Speed up log2f subnormals and log10f table access (PR #223718)

[via libc-commits]

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@@ -91,7 +92,13 @@ LIBC_INLINE float log2f(float x) {
       return x;
     }
     // Normalize denormal inputs.
-    xbits = FPBits(xbits.get_val() * 0x1.0p23f);
+    int biased_exponent = 32 - cpp::countl_zero(x_u);
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lntue wrote:

Let me try to get it tested on my Zen3 machine and I'll post the results here tomorrow.

https://github.com/llvm/llvm-project/pull/223718