[clang] [clang] Implement __builtin_stdc_rotate_left, __builtin_stdc_rotate_right (PR #160259)

[Eli Friedman via cfe-commits]

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@@ -64,3 +64,217 @@ long long rotr64(long long x, unsigned long long y) {
   return __builtin_rotateright64(x, y);
 }
 
+// CHECK-LABEL: test_builtin_stdc_rotate_left
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efriedma-quic wrote:

The CHECK lines here seem to miss some important bits.  A lot of the patch is dedicated to converting the shift amounts into the proper form; we should have some checks showing that we generate appropriate code.

https://github.com/llvm/llvm-project/pull/160259