[llvm] [VPlan] Use VPlan operand order for VPBlendRecipes. (PR #139475)

[via llvm-commits]

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@@ -20,9 +20,9 @@ define void @test(ptr %p, i64 %a, i8 %b) {
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[PRED_STORE_CONTINUE8:%.*]] ]
 ; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <16 x i32> [ <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[PRED_STORE_CONTINUE8]] ]
 ; CHECK-NEXT:    [[ACTIVE_LANE_MASK:%.*]] = call <16 x i1> @llvm.get.active.lane.mask.v16i1.i32(i32 [[INDEX]], i32 9)
-; CHECK-NEXT:    [[TMP4:%.*]] = icmp slt <16 x i32> [[VEC_IND]], splat (i32 2)
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp sge <16 x i32> [[VEC_IND]], splat (i32 2)
 ; CHECK-NEXT:    [[TMP5:%.*]] = select <16 x i1> [[ACTIVE_LANE_MASK]], <16 x i1> [[TMP4]], <16 x i1> zeroinitializer
-; CHECK-NEXT:    [[PREDPHI:%.*]] = select <16 x i1> [[TMP5]], <16 x i32> [[TMP3]], <16 x i32> [[TMP2]]
+; CHECK-NEXT:    [[PREDPHI:%.*]] = select <16 x i1> [[TMP5]], <16 x i32> [[TMP2]], <16 x i32> [[TMP3]]
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ayalz wrote:

Flipping select operands along with complementing its condition - the relevant part of which is masked via TMP5.

https://github.com/llvm/llvm-project/pull/139475