[libc] [llvm] [libc][math][c23] Add rsqrtf() function (PR #159615)

[Anton Shepelev via llvm-commits]

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@@ -67,6 +67,7 @@ TEST(LlvmLibcSharedMathTest, AllFloat) {
 
   ASSERT_FP_EQ(float(8 << 5), LIBC_NAMESPACE::shared::ldexpf(8.0f, 5));
   ASSERT_FP_EQ(float(-1 * (8 << 5)), LIBC_NAMESPACE::shared::ldexpf(-8.0f, 5));
+  EXPECT_FP_EQ(0x1p+0f, LIBC_NAMESPACE::shared::rsqrtf(1.0f));
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amemov wrote:

Ok, agree. I think to make it look better it would be a good idea to separate rsqrtf test from ldexpf by a new line

https://github.com/llvm/llvm-project/pull/159615