[llvm] [AArch64] Enable RT and partial unrolling with reductions for Apple CPUs. (PR #149699)

[Jonathan Cohen via llvm-commits]

================
@@ -603,27 +621,33 @@ define i32 @test_add_reduction_unroll_partial(ptr %a, i64 noundef %n) {
 ; OTHER-NEXT:    br label %[[LOOP:.*]]
 ; OTHER:       [[LOOP]]:
 ; OTHER-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT_3:%.*]], %[[LOOP]] ]
-; OTHER-NEXT:    [[RDX:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[RDX_NEXT_3:%.*]], %[[LOOP]] ]
+; OTHER-NEXT:    [[RDX_1:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[RDX_NEXT_1:%.*]], %[[LOOP]] ]
+; OTHER-NEXT:    [[RDX_2:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[RDX_NEXT_2:%.*]], %[[LOOP]] ]
+; OTHER-NEXT:    [[RDX_3:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[RDX_NEXT_3:%.*]], %[[LOOP]] ]
+; OTHER-NEXT:    [[RDX:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[RDX_NEXT:%.*]], %[[LOOP]] ]
 ; OTHER-NEXT:    [[GEP_A:%.*]] = getelementptr inbounds nuw i32, ptr [[A]], i64 [[IV]]
 ; OTHER-NEXT:    [[TMP0:%.*]] = load i32, ptr [[GEP_A]], align 2
-; OTHER-NEXT:    [[RDX_NEXT:%.*]] = add nuw nsw i32 [[RDX]], [[TMP0]]
+; OTHER-NEXT:    [[RDX_NEXT]] = add i32 [[RDX]], [[TMP0]]
 ; OTHER-NEXT:    [[IV_NEXT:%.*]] = add nuw nsw i64 [[IV]], 1
 ; OTHER-NEXT:    [[GEP_A_1:%.*]] = getelementptr inbounds nuw i32, ptr [[A]], i64 [[IV_NEXT]]
 ; OTHER-NEXT:    [[TMP1:%.*]] = load i32, ptr [[GEP_A_1]], align 2
-; OTHER-NEXT:    [[RDX_2:%.*]] = add nuw nsw i32 [[RDX_NEXT]], [[TMP1]]
+; OTHER-NEXT:    [[RDX_NEXT_1]] = add i32 [[RDX_1]], [[TMP1]]
 ; OTHER-NEXT:    [[IV_NEXT_1:%.*]] = add nuw nsw i64 [[IV]], 2
 ; OTHER-NEXT:    [[GEP_A_2:%.*]] = getelementptr inbounds nuw i32, ptr [[A]], i64 [[IV_NEXT_1]]
 ; OTHER-NEXT:    [[TMP2:%.*]] = load i32, ptr [[GEP_A_2]], align 2
-; OTHER-NEXT:    [[RDX_NEXT_2:%.*]] = add nuw nsw i32 [[RDX_2]], [[TMP2]]
+; OTHER-NEXT:    [[RDX_NEXT_2]] = add i32 [[RDX_2]], [[TMP2]]
 ; OTHER-NEXT:    [[IV_NEXT_2:%.*]] = add nuw nsw i64 [[IV]], 3
 ; OTHER-NEXT:    [[GEP_A_3:%.*]] = getelementptr inbounds nuw i32, ptr [[A]], i64 [[IV_NEXT_2]]
 ; OTHER-NEXT:    [[TMP3:%.*]] = load i32, ptr [[GEP_A_3]], align 2
-; OTHER-NEXT:    [[RDX_NEXT_3]] = add nuw nsw i32 [[RDX_NEXT_2]], [[TMP3]]
----------------
jcohen-apple wrote:

Are we dropping the flags here on purpose?

https://github.com/llvm/llvm-project/pull/149699