[llvm] [LV] Vectorize bounded (i % 2^N) loads in read only loops w/o RT checks. (PR #207279)

[David Sherwood via llvm-commits]

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@@ -229,79 +197,91 @@ exit:
 define i16 @bounded_load_reduction_bound4_i16(ptr %A, i32 %N) {
 ; CHECK-LABEL: define i16 @bounded_load_reduction_bound4_i16(
 ; CHECK-SAME: ptr [[A:%.*]], i32 [[N:%.*]]) {
-; CHECK-NEXT:  [[ITER_CHECK:.*]]:
+; CHECK-NEXT:  [[ENTRY:.*]]:
 ; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i32 [[N]], 4
-; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[VEC_EPILOG_SCALAR_PH:.*]], label %[[VECTOR_SCEVCHECK:.*]]
-; CHECK:       [[VECTOR_SCEVCHECK]]:
-; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[N]], -1
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp ugt i32 [[TMP0]], 3
-; CHECK-NEXT:    br i1 [[TMP1]], label %[[VEC_EPILOG_SCALAR_PH]], label %[[VECTOR_MAIN_LOOP_ITER_CHECK:.*]]
-; CHECK:       [[VECTOR_MAIN_LOOP_ITER_CHECK]]:
-; CHECK-NEXT:    [[MIN_ITERS_CHECK1:%.*]] = icmp ult i32 [[N]], 16
-; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK1]], label %[[VEC_EPILOG_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
 ; CHECK:       [[VECTOR_PH]]:
-; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i32 [[N]], 16
+; CHECK-NEXT:    [[MIN_ITERS_CHECK1:%.*]] = icmp ult i32 [[N]], 16
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK1]], label %[[VEC_EPILOG_PH:.*]], label %[[VECTOR_PH1:.*]]
+; CHECK:       [[VECTOR_PH1]]:
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david-arm wrote:

Looks like the variable names need regenerating here.

https://github.com/llvm/llvm-project/pull/207279