[LV][AArch64][NFC]: Change TC in a test file.

- In sve-epilog-vscale-fixed.ll file, it tests the preference of
  fixed-width epilogue VF vs scalable when costs are equal.
  This NFC patch is changing the TC in the test case to be unknown to
  avoid folding the epilogue in future LV changes.

Author: hassnaaHamdi

llvm/test/Transforms/LoopVectorize/AArch64/sve-epilog-vscale-fixed.ll

@@ -24,20 +24,21 @@ target triple = "aarch64-linux-gnu"
 ; DEBUG-EPILOG-PREFER-SCALABLE: Create Skeleton for epilogue vectorized loop (first pass)
 ; DEBUG-EPILOG-PREFER-SCALABLE: Main Loop VF:vscale x 16, Main Loop UF:2, Epilogue Loop VF:vscale x 8, Epilogue Loop UF:1
 
-define void @main_vf_vscale_x_16(ptr %A) #0 {
+define void @main_vf_vscale_x_16(ptr %A, i64 %n) #0 {
 ; CHECK-LABEL: @main_vf_vscale_x_16(
 ; CHECK-NEXT:  iter.check:
-; CHECK-NEXT:    br i1 false, label [[VEC_EPILOG_SCALAR_PH:%.*]], label [[VECTOR_MAIN_LOOP_ITER_CHECK:%.*]]
+; CHECK-NEXT:    [[MIN_ITERS_CHECK1:%.*]] = icmp ult i64 [[N:%.*]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK1]], label [[VEC_EPILOG_SCALAR_PH:%.*]], label [[VECTOR_MAIN_LOOP_ITER_CHECK:%.*]]
 ; CHECK:       vector.main.loop.iter.check:
 ; CHECK-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-NEXT:    [[TMP1:%.*]] = shl nuw i64 [[TMP0]], 5
-; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 1024, [[TMP1]]
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], [[TMP1]]
 ; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[VEC_EPILOG_PH:%.*]], label [[VECTOR_PH:%.*]]
 ; CHECK:       vector.ph:
 ; CHECK-NEXT:    [[TMP2:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-NEXT:    [[TMP3:%.*]] = mul nuw i64 [[TMP2]], 32
-; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 1024, [[TMP3]]
-; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 1024, [[N_MOD_VF]]
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], [[TMP3]]
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
 ; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; CHECK:       vector.body:
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
@@ -51,45 +52,48 @@ define void @main_vf_vscale_x_16(ptr %A) #0 {
 ; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[TMP8]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
 ; CHECK:       middle.block:
-; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1024, [[N_VEC]]
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[VEC_EPILOG_ITER_CHECK:%.*]]
 ; CHECK:       vec.epilog.iter.check:
-; CHECK-NEXT:    [[N_VEC_REMAINING:%.*]] = sub i64 1024, [[N_VEC]]
+; CHECK-NEXT:    [[N_VEC_REMAINING:%.*]] = sub i64 [[N]], [[N_VEC]]
 ; CHECK-NEXT:    [[MIN_EPILOG_ITERS_CHECK:%.*]] = icmp ult i64 [[N_VEC_REMAINING]], 8
-; CHECK-NEXT:    br i1 [[MIN_EPILOG_ITERS_CHECK]], label [[VEC_EPILOG_SCALAR_PH]], label [[VEC_EPILOG_PH]]
+; CHECK-NEXT:    br i1 [[MIN_EPILOG_ITERS_CHECK]], label [[VEC_EPILOG_SCALAR_PH]], label [[VEC_EPILOG_PH]], !prof [[PROF3:![0-9]+]]
 ; CHECK:       vec.epilog.ph:
 ; CHECK-NEXT:    [[VEC_EPILOG_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[VECTOR_MAIN_LOOP_ITER_CHECK]] ]
+; CHECK-NEXT:    [[N_MOD_VF2:%.*]] = urem i64 [[N]], 8
+; CHECK-NEXT:    [[N_VEC3:%.*]] = sub i64 [[N]], [[N_MOD_VF2]]
 ; CHECK-NEXT:    br label [[VEC_EPILOG_VECTOR_BODY:%.*]]
 ; CHECK:       vec.epilog.vector.body:
 ; CHECK-NEXT:    [[INDEX1:%.*]] = phi i64 [ [[VEC_EPILOG_RESUME_VAL]], [[VEC_EPILOG_PH]] ], [ [[INDEX_NEXT2:%.*]], [[VEC_EPILOG_VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDEX1]]
 ; CHECK-NEXT:    store <8 x i8> splat (i8 1), ptr [[TMP9]], align 1
 ; CHECK-NEXT:    [[INDEX_NEXT2]] = add nuw i64 [[INDEX1]], 8
-; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq i64 [[INDEX_NEXT2]], 1024
-; CHECK-NEXT:    br i1 [[TMP10]], label [[VEC_EPILOG_MIDDLE_BLOCK:%.*]], label [[VEC_EPILOG_VECTOR_BODY]], !llvm.loop [[LOOP3:![0-9]+]]
+; CHECK-NEXT:    [[TMP10:%.*]] = icmp eq i64 [[INDEX_NEXT2]], [[N_VEC3]]
+; CHECK-NEXT:    br i1 [[TMP10]], label [[VEC_EPILOG_MIDDLE_BLOCK:%.*]], label [[VEC_EPILOG_VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; CHECK:       vec.epilog.middle.block:
-; CHECK-NEXT:    br i1 true, label [[EXIT]], label [[VEC_EPILOG_SCALAR_PH]]
+; CHECK-NEXT:    [[CMP_N6:%.*]] = icmp eq i64 [[N]], [[N_VEC3]]
+; CHECK-NEXT:    br i1 [[CMP_N6]], label [[EXIT]], label [[VEC_EPILOG_SCALAR_PH]]
 ; CHECK:       vec.epilog.scalar.ph:
-; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ 1024, [[VEC_EPILOG_MIDDLE_BLOCK]] ], [ [[N_VEC]], [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[ITER_CHECK:%.*]] ]
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC3]], [[VEC_EPILOG_MIDDLE_BLOCK]] ], [ [[N_VEC]], [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[ITER_CHECK:%.*]] ]
 ; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
 ; CHECK:       for.body:
 ;
 ; CHECK-EPILOG-PREFER-SCALABLE-LABEL: @main_vf_vscale_x_16(
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:  iter.check:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP1:%.*]] = shl nuw i64 [[TMP0]], 3
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 1024, [[TMP1]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N:%.*]], [[TMP1]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[VEC_EPILOG_SCALAR_PH:%.*]], label [[VECTOR_MAIN_LOOP_ITER_CHECK:%.*]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vector.main.loop.iter.check:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP2:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP3:%.*]] = shl nuw i64 [[TMP2]], 5
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[MIN_ITERS_CHECK1:%.*]] = icmp ult i64 1024, [[TMP3]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[MIN_ITERS_CHECK1:%.*]] = icmp ult i64 [[N]], [[TMP3]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[MIN_ITERS_CHECK1]], label [[VEC_EPILOG_PH:%.*]], label [[VECTOR_PH:%.*]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vector.ph:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP4:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP5:%.*]] = mul nuw i64 [[TMP4]], 32
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_MOD_VF:%.*]] = urem i64 1024, [[TMP5]]
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC:%.*]] = sub i64 1024, [[N_MOD_VF]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], [[TMP5]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vector.body:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
@@ -103,30 +107,30 @@ define void @main_vf_vscale_x_16(ptr %A) #0 {
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP10:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[TMP10]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       middle.block:
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[CMP_N:%.*]] = icmp eq i64 1024, [[N_VEC]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[VEC_EPILOG_ITER_CHECK:%.*]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vec.epilog.iter.check:
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC_REMAINING:%.*]] = sub i64 1024, [[N_VEC]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC_REMAINING:%.*]] = sub i64 [[N]], [[N_VEC]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP11:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP12:%.*]] = shl nuw i64 [[TMP11]], 3
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[MIN_EPILOG_ITERS_CHECK:%.*]] = icmp ult i64 [[N_VEC_REMAINING]], [[TMP12]]
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[MIN_EPILOG_ITERS_CHECK]], label [[VEC_EPILOG_SCALAR_PH]], label [[VEC_EPILOG_PH]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[MIN_EPILOG_ITERS_CHECK]], label [[VEC_EPILOG_SCALAR_PH]], label [[VEC_EPILOG_PH]], !prof [[PROF3:![0-9]+]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vec.epilog.ph:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[VEC_EPILOG_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[VECTOR_MAIN_LOOP_ITER_CHECK]] ]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP13:%.*]] = call i64 @llvm.vscale.i64()
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP14:%.*]] = mul nuw i64 [[TMP13]], 8
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_MOD_VF2:%.*]] = urem i64 1024, [[TMP14]]
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC3:%.*]] = sub i64 1024, [[N_MOD_VF2]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_MOD_VF2:%.*]] = urem i64 [[N]], [[TMP14]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[N_VEC3:%.*]] = sub i64 [[N]], [[N_MOD_VF2]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br label [[VEC_EPILOG_VECTOR_BODY:%.*]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vec.epilog.vector.body:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[INDEX4:%.*]] = phi i64 [ [[VEC_EPILOG_RESUME_VAL]], [[VEC_EPILOG_PH]] ], [ [[INDEX_NEXT5:%.*]], [[VEC_EPILOG_VECTOR_BODY]] ]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP15:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDEX4]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    store <vscale x 8 x i8> splat (i8 1), ptr [[TMP15]], align 1
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[INDEX_NEXT5]] = add nuw i64 [[INDEX4]], [[TMP14]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[TMP16:%.*]] = icmp eq i64 [[INDEX_NEXT5]], [[N_VEC3]]
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[TMP16]], label [[VEC_EPILOG_MIDDLE_BLOCK:%.*]], label [[VEC_EPILOG_VECTOR_BODY]], !llvm.loop [[LOOP3:![0-9]+]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[TMP16]], label [[VEC_EPILOG_MIDDLE_BLOCK:%.*]], label [[VEC_EPILOG_VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vec.epilog.middle.block:
-; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[CMP_N6:%.*]] = icmp eq i64 1024, [[N_VEC3]]
+; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[CMP_N6:%.*]] = icmp eq i64 [[N]], [[N_VEC3]]
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    br i1 [[CMP_N6]], label [[EXIT]], label [[VEC_EPILOG_SCALAR_PH]]
 ; CHECK-EPILOG-PREFER-SCALABLE:       vec.epilog.scalar.ph:
 ; CHECK-EPILOG-PREFER-SCALABLE-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC3]], [[VEC_EPILOG_MIDDLE_BLOCK]] ], [ [[N_VEC]], [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[ITER_CHECK:%.*]] ]
@@ -141,7 +145,7 @@ for.body:
   %arrayidx = getelementptr inbounds i8, ptr %A, i64 %iv
   store i8 1, ptr %arrayidx, align 1
   %iv.next = add nuw nsw i64 %iv, 1
-  %exitcond = icmp ne i64 %iv.next, 1024
+  %exitcond = icmp ne i64 %iv.next, %n
   br i1 %exitcond, label %for.body, label %exit
 
 exit: