[libc] [llvm] [libc][math] Improve atanf performance. (PR #85463)

[via llvm-commits]

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@@ -53,8 +53,9 @@ TEST_F(LlvmLibcAtanfTest, InFloatRange) {
 
 // For small values, tanh(x) is x.
 TEST_F(LlvmLibcAtanfTest, SpecialValues) {
-  uint32_t val_arr[] = {0x3d8d6b23U, 0x3feefcfbU, 0xbd8d6b23U,
-                        0xbfeefcfbU, 0x7F800000U, 0xFF800000U};
+  uint32_t val_arr[] = {
+      0x3d8d6b23U, 0x3feefcfbU, 0xbd8d6b23U, 0xbfeefcfbU,
+      0x7F800000U, 0xFF800000U, 0xbffe2ec1U /*-0x1.fc5d82p+0*/};
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lntue wrote:

The array elements are `uint32_t` bit patterns, and I added the corresponding float value to the comment.  Probably I should add the corresponding float values for the rest of them.

https://github.com/llvm/llvm-project/pull/85463