[SCEV][LoopUnroll] Add pre-commit tests. NFC.

Author: dtcxzyw

llvm/test/Analysis/ScalarEvolution/trip-count-unknown-stride.ll

@@ -493,6 +493,27 @@ for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
+define i32 @pr131465(i1 %x) mustprogress {
+; CHECK-LABEL: 'pr131465'
+; CHECK-NEXT:  Determining loop execution counts for: @pr131465
+; CHECK-NEXT:  Loop %for.body: backedge-taken count is ((-1 * (zext i1 %x to i32))<nuw><nsw> /u (zext i1 %x to i32))
+; CHECK-NEXT:  Loop %for.body: constant max backedge-taken count is i32 -1
+; CHECK-NEXT:  Loop %for.body: symbolic max backedge-taken count is ((-1 * (zext i1 %x to i32))<nuw><nsw> /u (zext i1 %x to i32))
+; CHECK-NEXT:  Loop %for.body: Trip multiple is 1
+;
+entry:
+  %inc = zext i1 %x to i32
+  br label %for.body
+
+for.body:
+  %indvar = phi i32 [ 2, %entry ], [ %next, %for.body ]
+  %next = add nsw i32 %indvar, %inc
+  %exitcond = icmp eq i32 %next, 2
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret i32 0
+}
 
 declare void @llvm.assume(i1)
 

llvm/test/Transforms/LoopUnroll/pr131465.ll

@@ -0,0 +1,57 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -passes=loop-unroll -unroll-runtime %s | FileCheck %s
+
+define i32 @pr131465(i1 %x) mustprogress {
+; CHECK-LABEL: define i32 @pr131465(
+; CHECK-SAME: i1 [[X:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[INC:%.*]] = zext i1 [[X]] to i32
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i32 0, [[INC]]
+; CHECK-NEXT:    [[TMP1:%.*]] = udiv i32 [[TMP0]], [[INC]]
+; CHECK-NEXT:    [[TMP2:%.*]] = add i32 [[TMP1]], 1
+; CHECK-NEXT:    [[XTRAITER:%.*]] = and i32 [[TMP2]], 1
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ult i32 [[TMP1]], 1
+; CHECK-NEXT:    br i1 [[TMP3]], label %[[FOR_END_UNR_LCSSA:.*]], label %[[ENTRY_NEW:.*]]
+; CHECK:       [[ENTRY_NEW]]:
+; CHECK-NEXT:    [[UNROLL_ITER:%.*]] = sub i32 [[TMP2]], [[XTRAITER]]
+; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[INDVAR:%.*]] = phi i32 [ 2, %[[ENTRY_NEW]] ], [ [[NEXT_1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[NITER:%.*]] = phi i32 [ 0, %[[ENTRY_NEW]] ], [ [[NITER_NEXT_1:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[NEXT:%.*]] = add nsw i32 [[INDVAR]], [[INC]]
+; CHECK-NEXT:    [[NEXT_1]] = add nsw i32 [[NEXT]], [[INC]]
+; CHECK-NEXT:    [[NITER_NEXT_1]] = add i32 [[NITER]], 2
+; CHECK-NEXT:    [[NITER_NCMP_1:%.*]] = icmp eq i32 [[NITER_NEXT_1]], [[UNROLL_ITER]]
+; CHECK-NEXT:    br i1 [[NITER_NCMP_1]], label %[[FOR_END_UNR_LCSSA_LOOPEXIT:.*]], label %[[FOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[FOR_END_UNR_LCSSA_LOOPEXIT]]:
+; CHECK-NEXT:    br label %[[FOR_END_UNR_LCSSA]]
+; CHECK:       [[FOR_END_UNR_LCSSA]]:
+; CHECK-NEXT:    [[LCMP_MOD:%.*]] = icmp ne i32 [[XTRAITER]], 0
+; CHECK-NEXT:    br i1 [[LCMP_MOD]], label %[[FOR_BODY_EPIL_PREHEADER:.*]], label %[[FOR_END:.*]]
+; CHECK:       [[FOR_BODY_EPIL_PREHEADER]]:
+; CHECK-NEXT:    br label %[[FOR_BODY_EPIL:.*]]
+; CHECK:       [[FOR_BODY_EPIL]]:
+; CHECK-NEXT:    br label %[[FOR_END]]
+; CHECK:       [[FOR_END]]:
+; CHECK-NEXT:    ret i32 0
+;
+entry:
+  %inc = zext i1 %x to i32
+  br label %for.body
+
+for.body:
+  %indvar = phi i32 [ 2, %entry ], [ %next, %for.body ]
+  %next = add nsw i32 %indvar, %inc
+  %exitcond = icmp eq i32 %next, 2
+  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !0
+
+for.end:
+  ret i32 0
+}
+
+; Force runtime unrolling.
+!0 = !{!0, !{!"llvm.loop.unroll.count", i32 2}}
+;.
+; CHECK: [[LOOP0]] = distinct !{[[LOOP0]], [[META1:![0-9]+]]}
+; CHECK: [[META1]] = !{!"llvm.loop.unroll.disable"}
+;.