[llvm] Add 3 way compare <=> integer intrinsics to Langref (PR #83227)

[Miguel Raz Guzmán Macedo via llvm-commits]

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@@ -0,0 +1,22 @@
+; RUN: not opt -S -passes=verify 2>&1 < %s | FileCheck %s
+
+
+define @matching_vector_lens(<4 x i32> %arg1, <4 x i32> %arg2) {
+	; CHECK-LABEL: cmp_vector_lens_match
+	; CHECK: return type and first arg type must have the same number of elements
+	%res = call <8 x i32> @llvm.scmp.v8i32.v4i32(<4 x i32> %arg1, <4 x i32> %arg2)
+}
+
+define @result_len_is_at_least_2(i32 %arg1, i32 %arg2) {
+	; CHECK-LABEL: cmp_result_len_is_at_least_2bits_wide
+	; CHECK: result type must be at least 2 bits wide
+	%res2 = call i1 @llvm.scmp.i1.i32(i32 %arg1, i32 %arg2)
+}
+
+define @both_args_are_vecs_or_neither(<4 x i32> %arg1, i32 %arg2) {
+	; CHECK-LABEL: cmp_sources_and_dest_types_ranks_match
+	; CHECK: [us]cmp source and destination must both be a vector or neither
+	@res3 = call i2 @llvm.scmp.i2.v4i32(<4 x i32> %arg1, i32 %arg2)
+	; CHECK: [us]cmp source and destination must both be a vector or neither
+	@res4 = call <4 x i32> @llvm.scmp.v4i32.i32(<4 x i32> %arg2, i32 %arg2)
+}
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miguelraz wrote:

Well, I'm part of the `portable-simd` team on the Rust compiler team (albeit on the junior side there) so I'm game to learn more about RISCV stuff as a stretch goal 🕺🏾 , but I'll defer to what @nikic thinks is in scope.

https://github.com/llvm/llvm-project/pull/83227