[llvm] [AArch64] Add fixed-length SVE USDOT support (PR #143730)

[Sander de Smalen via llvm-commits]

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@@ -407,6 +407,33 @@ define <4 x i32> @four_way_i8_i32_vl128(ptr %accptr, ptr %uptr, ptr %sptr) {
   ret <4 x i32> %partial.reduce
 }
 
+define <4 x i32> @four_way_i8_i32_vl128_usdot(ptr %accptr, ptr %uptr, ptr %sptr) {
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sdesmalen-arm wrote:

Could you also add a test where the zext and sext are reversed? (to ensure that we still get the usdot)
And perhaps a negative test where the element types are such that they don't result in a usdot (e.g. i8 -> i64).

https://github.com/llvm/llvm-project/pull/143730