[X86] Use the unaligned vector typedefs for the lddqu intrinsics pointer arguments (PR20670)

Extension to 4390c72 - similar to the vanilla load/store intrinsics, _mm_lddqu_si128/_mm256_lddqu_si256 should take an unaligned pointer, but were using the aligned m128i/m256i types which can cause alignment warnings.

The existing sse3-builtins.c and avx-builtins.c tests in llvm-project\clang\test\CodeGen\X86 should cover this.

Differential Revision: https://reviews.llvm.org/D121815

Author: RKSimon

clang/lib/Headers/avxintrin.h

@@ -3177,7 +3177,7 @@ _mm256_loadu_si256(__m256i_u const *__p)
 ///    A pointer to a 256-bit integer vector containing integer values.
 /// \returns A 256-bit integer vector containing the moved values.
 static __inline __m256i __DEFAULT_FN_ATTRS
-_mm256_lddqu_si256(__m256i const *__p)
+_mm256_lddqu_si256(__m256i_u const *__p)
 {
   return (__m256i)__builtin_ia32_lddqu256((char const *)__p);
 }

clang/lib/Headers/pmmintrin.h

@@ -35,7 +35,7 @@
 ///    A pointer to a 128-bit integer vector containing integer values.
 /// \returns A 128-bit vector containing the moved values.
 static __inline__ __m128i __DEFAULT_FN_ATTRS
-_mm_lddqu_si128(__m128i const *__p)
+_mm_lddqu_si128(__m128i_u const *__p)
 {
   return (__m128i)__builtin_ia32_lddqu((char const *)__p);
 }