[clang] [Clang][LoongArch] Fixed incorrect _BitInt(N>64) alignment (PR #145297)

[Lu Weining via cfe-commits]

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@@ -0,0 +1,36 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+// RUN: %clang_cc1 -triple loongarch64 -fexperimental-max-bitint-width=1024 -emit-llvm %s -o - | FileCheck %s
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SixWeining wrote:

- It's better to add some comments explaining the testing purpose.
- Also test loongarch32.
- Test different `N` values (e.g. 1/65/129) and rename the file name from `bitint-large.c` to `bitint.c`.
- Pre-commit the test before this PR so that we can see the effect.

https://github.com/llvm/llvm-project/pull/145297