[compiler-rt] [compiler-rt] Add initial ARM64EC builtins support (PR #139279)

[Martin Storsjö via llvm-commits]

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@@ -31,22 +44,28 @@ int main()
 {
 #if defined(__ve__)
     unsigned char execution_buffer[128] __attribute__((__aligned__(8)));
+#elif defined(__x86_64__)
+  unsigned char execution_buffer[sizeof(func1)];
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mstorsjo wrote:

Why do we need to shrink the buffer here?

https://github.com/llvm/llvm-project/pull/139279