diff --git a/llvm/test/Transforms/InstCombine/icmp-fold-into-phi.ll b/llvm/test/Transforms/InstCombine/icmp-fold-into-phi.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/icmp-fold-into-phi.ll
@@ -0,0 +1,203 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+define i1 @SimpleTest(i32 %x, i32 %y) {
+; CHECK-LABEL: define i1 @SimpleTest
+; CHECK-SAME: (i32 [[X:%.*]], i32 [[Y:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    switch i32 [[X]], label [[BB1:%.*]] [
+; CHECK-NEXT:    i32 0, label [[BB2:%.*]]
+; CHECK-NEXT:    i32 1, label [[BB3:%.*]]
+; CHECK-NEXT:    ]
+; CHECK:       bb1:
+; CHECK-NEXT:    br label [[BB2]]
+; CHECK:       bb2:
+; CHECK-NEXT:    [[PHI1:%.*]] = phi i32 [ 1, [[ENTRY:%.*]] ], [ [[Y]], [[BB1]] ]
+; CHECK-NEXT:    br label [[BB3]]
+; CHECK:       bb3:
+; CHECK-NEXT:    [[PHI2:%.*]] = phi i32 [ [[PHI1]], [[BB2]] ], [ 0, [[ENTRY]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i32 [[PHI2]], 1
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+entry:
+  switch i32 %x, label %bb1 [
+  i32 0, label %bb2
+  i32 1, label %bb3
+  ]
+
+bb1:
+  br label %bb2
+
+bb2:
+  %phi1 = phi i32 [ 1, %entry ], [ %y, %bb1 ]
+  br label %bb3
+
+bb3:
+  %phi2 = phi i32 [ %phi1, %bb2 ], [ 0, %entry ]
+  %cmp = icmp ugt i32 %phi2, 1
+  ret i1 %cmp
+}
+
+; Test case derived from:
+; llvm-test-suite/MultiSource/Benchmarks/MiBench/consumer-typeset/z10.c
+@ObjTag  = external global i32, align 4
+@ObjVal  = external global ptr, align 8
+@RetVal1 = external global i32, align 4
+@RetVal2 = external global i32, align 4
+
+@.str   = constant [2 x i8] zeroinitializer, align 1
+@.str.1 = constant [4 x i8] c"TWO\00", align 1
+@.str.2 = constant [6 x i8] c"THREE\00", align 1
+@.str.3 = constant [5 x i8] c"FOUR\00", align 1
+
+define i32 @Compute() {
+; CHECK-LABEL: define i32 @Compute() {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr @ObjTag, align 4
+; CHECK-NEXT:    [[CALL:%.*]] = tail call zeroext i1 @CheckValue(i32 noundef [[TMP0]])
+; CHECK-NEXT:    br i1 [[CALL]], label [[SW_EPILOG:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    [[TMP1:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL1:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP1]], ptr noundef nonnull @.str)
+; CHECK-NEXT:    br i1 [[CALL1]], label [[SW_EPILOG]], label [[COND_FALSE2:%.*]]
+; CHECK:       cond.false2:
+; CHECK-NEXT:    [[TMP2:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL2:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP2]], ptr noundef nonnull @.str.1)
+; CHECK-NEXT:    br i1 [[CALL2]], label [[SW_EPILOG]], label [[COND_FALSE3:%.*]]
+; CHECK:       cond.false3:
+; CHECK-NEXT:    [[TMP3:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL3:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP3]], ptr noundef nonnull @.str.2)
+; CHECK-NEXT:    br i1 [[CALL3]], label [[SW_BB:%.*]], label [[COND_END:%.*]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[TMP4:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL4:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP4]], ptr noundef nonnull @.str.3)
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CALL4]], i32 127, i32 126
+; CHECK-NEXT:    br label [[SW_BB]]
+; CHECK:       sw.bb:
+; CHECK-NEXT:    [[COND2:%.*]] = phi i32 [ [[COND]], [[COND_END]] ], [ 128, [[COND_FALSE3]] ]
+; CHECK-NEXT:    [[CALL5:%.*]] = tail call zeroext i1 @CheckCond()
+; CHECK-NEXT:    [[NOT_CALL5:%.*]] = xor i1 [[CALL5]], true
+; CHECK-NEXT:    br label [[SW_EPILOG]]
+; CHECK:       sw.epilog:
+; CHECK-NEXT:    [[COND3:%.*]] = phi i32 [ [[COND2]], [[SW_BB]] ], [ 134, [[COND_FALSE2]] ], [ 2, [[COND_FALSE]] ], [ 1, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[TAGERROR_0:%.*]] = phi i1 [ [[NOT_CALL5]], [[SW_BB]] ], [ false, [[COND_FALSE2]] ], [ false, [[COND_FALSE]] ], [ false, [[ENTRY]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i32 [[COND3]], 2
+; CHECK-NEXT:    [[BRMERGE:%.*]] = or i1 [[CMP]], [[TAGERROR_0]]
+; CHECK-NEXT:    [[RETVAL2_VAL:%.*]] = load i32, ptr @RetVal2, align 4
+; CHECK-NEXT:    [[RETVAL1_VAL:%.*]] = load i32, ptr @RetVal1, align 4
+; CHECK-NEXT:    [[RETVAL_0:%.*]] = select i1 [[BRMERGE]], i32 [[RETVAL2_VAL]], i32 [[RETVAL1_VAL]]
+; CHECK-NEXT:    ret i32 [[RETVAL_0]]
+;
+entry:
+  %0    = load i32, ptr @ObjTag, align 4
+  %call = tail call zeroext i1 @CheckValue(i32 noundef %0)
+  br i1 %call, label %sw.epilog, label %cond.false
+
+cond.false:
+  %1     = load ptr, ptr @ObjVal, align 8
+  %call1 = tail call zeroext i1 @StrCmp(ptr noundef %1, ptr noundef nonnull @.str)
+  br i1 %call1, label %sw.epilog, label %cond.false2
+
+cond.false2:
+  %2     = load ptr, ptr @ObjVal, align 8
+  %call2 = tail call zeroext i1 @StrCmp(ptr noundef %2, ptr noundef nonnull @.str.1)
+  br i1 %call2, label %sw.epilog, label %cond.false3
+
+cond.false3:
+  %3     = load ptr, ptr @ObjVal, align 8
+  %call3 = tail call zeroext i1 @StrCmp(ptr noundef %3, ptr noundef nonnull @.str.2)
+  br i1 %call3, label %sw.bb, label %cond.end
+
+cond.end:
+  %4     = load ptr, ptr @ObjVal, align 8
+  %call4 = tail call zeroext i1 @StrCmp(ptr noundef %4, ptr noundef nonnull @.str.3)
+  %cond  = select i1 %call4, i32 127, i32 126
+  br label %sw.bb
+
+sw.bb:
+  %cond2     = phi i32 [ %cond, %cond.end ], [ 128, %cond.false3 ]
+  %call5     = tail call zeroext i1 @CheckCond()
+  %not.call5 = xor i1 %call5, true
+  br label %sw.epilog
+
+sw.epilog:
+  %cond3       = phi i32 [ %cond2, %sw.bb ], [ 134, %cond.false2 ], [ 2, %cond.false ], [ 1, %entry ]
+  %TagError.0  = phi i1 [ %not.call5, %sw.bb ], [ false, %cond.false2 ], [ false, %cond.false ], [ false, %entry ]
+  %cmp         = icmp ult i32 %cond3, 2
+  %brmerge     = or i1 %cmp, %TagError.0
+  %RetVal2.val = load i32, ptr @RetVal2, align 4
+  %RetVal1.val = load i32, ptr @RetVal1, align 4
+  %retval.0    = select i1 %brmerge, i32 %RetVal2.val, i32 %RetVal1.val
+  ret i32 %retval.0
+}
+
+define i1 @ComputeSimplified() {
+; CHECK-LABEL: define i1 @ComputeSimplified() {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr @ObjTag, align 4
+; CHECK-NEXT:    [[CALL:%.*]] = tail call zeroext i1 @CheckValue(i32 noundef [[TMP0]])
+; CHECK-NEXT:    br i1 [[CALL]], label [[SW_EPILOG:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    [[TMP1:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL1:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP1]], ptr noundef nonnull @.str)
+; CHECK-NEXT:    br i1 [[CALL1]], label [[SW_EPILOG]], label [[COND_FALSE2:%.*]]
+; CHECK:       cond.false2:
+; CHECK-NEXT:    [[TMP2:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL2:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP2]], ptr noundef nonnull @.str.1)
+; CHECK-NEXT:    br i1 [[CALL2]], label [[SW_EPILOG]], label [[COND_FALSE3:%.*]]
+; CHECK:       cond.false3:
+; CHECK-NEXT:    [[TMP3:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL3:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP3]], ptr noundef nonnull @.str.2)
+; CHECK-NEXT:    br i1 [[CALL3]], label [[SW_BB:%.*]], label [[COND_END:%.*]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[TMP4:%.*]] = load ptr, ptr @ObjVal, align 8
+; CHECK-NEXT:    [[CALL4:%.*]] = tail call zeroext i1 @StrCmp(ptr noundef [[TMP4]], ptr noundef nonnull @.str.3)
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CALL4]], i32 127, i32 126
+; CHECK-NEXT:    br label [[SW_BB]]
+; CHECK:       sw.bb:
+; CHECK-NEXT:    [[COND2:%.*]] = phi i32 [ [[COND]], [[COND_END]] ], [ 128, [[COND_FALSE3]] ]
+; CHECK-NEXT:    br label [[SW_EPILOG]]
+; CHECK:       sw.epilog:
+; CHECK-NEXT:    [[COND3:%.*]] = phi i32 [ [[COND2]], [[SW_BB]] ], [ 134, [[COND_FALSE2]] ], [ 2, [[COND_FALSE]] ], [ 1, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i32 [[COND3]], 2
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+entry:
+  %0    = load i32, ptr @ObjTag, align 4
+  %call = tail call zeroext i1 @CheckValue(i32 noundef %0)
+  br i1 %call, label %sw.epilog, label %cond.false
+
+cond.false:
+  %1     = load ptr, ptr @ObjVal, align 8
+  %call1 = tail call zeroext i1 @StrCmp(ptr noundef %1, ptr noundef nonnull @.str)
+  br i1 %call1, label %sw.epilog, label %cond.false2
+
+cond.false2:
+  %2     = load ptr, ptr @ObjVal, align 8
+  %call2 = tail call zeroext i1 @StrCmp(ptr noundef %2, ptr noundef nonnull @.str.1)
+  br i1 %call2, label %sw.epilog, label %cond.false3
+
+cond.false3:
+  %3     = load ptr, ptr @ObjVal, align 8
+  %call3 = tail call zeroext i1 @StrCmp(ptr noundef %3, ptr noundef nonnull @.str.2)
+  br i1 %call3, label %sw.bb, label %cond.end
+
+cond.end:
+  %4     = load ptr, ptr @ObjVal, align 8
+  %call4 = tail call zeroext i1 @StrCmp(ptr noundef %4, ptr noundef nonnull @.str.3)
+  %cond  = select i1 %call4, i32 127, i32 126
+  br label %sw.bb
+
+sw.bb:
+  %cond2 = phi i32 [ %cond, %cond.end ], [ 128, %cond.false3 ]
+  br label %sw.epilog
+
+sw.epilog:
+  %cond3 = phi i32 [ %cond2, %sw.bb ], [ 134, %cond.false2 ], [ 2, %cond.false ], [ 1, %entry ]
+  %cmp   = icmp ult i32 %cond3, 2
+  ret i1 %cmp
+}
+
+declare zeroext i1 @CheckValue(i32 noundef)
+declare zeroext i1 @StrCmp(ptr noundef, ptr noundef)
+declare zeroext i1 @CheckCond()