Index: llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
===================================================================
--- llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
+++ llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -261,13 +261,16 @@
   const SCEV *S = SE->getSCEVAtScope(ICmp->getOperand(IVOperIdx), ICmpLoop);
   const SCEV *X = SE->getSCEVAtScope(ICmp->getOperand(1 - IVOperIdx), ICmpLoop);
 
-  // If the condition is always true or always false, replace it with
-  // a constant value.
-  if (SE->isKnownPredicate(Pred, S, X)) {
+  // If the condition is always true or always false, in the given context,
+  // replace it witha constant value.
+  // TODO: We can sharpen the context to common dominator of all ICmp's users.
+  const Instruction *Context = ICmp;
+  if (SE->isKnownPredicateAt(Pred, S, X, Context)) {
     ICmp->replaceAllUsesWith(ConstantInt::getTrue(ICmp->getContext()));
     DeadInsts.emplace_back(ICmp);
     LLVM_DEBUG(dbgs() << "INDVARS: Eliminated comparison: " << *ICmp << '\n');
-  } else if (SE->isKnownPredicate(ICmpInst::getInversePredicate(Pred), S, X)) {
+  } else if (SE->isKnownPredicateAt(ICmpInst::getInversePredicate(Pred), S, X,
+                                    Context)) {
     ICmp->replaceAllUsesWith(ConstantInt::getFalse(ICmp->getContext()));
     DeadInsts.emplace_back(ICmp);
     LLVM_DEBUG(dbgs() << "INDVARS: Eliminated comparison: " << *ICmp << '\n');
Index: llvm/test/Transforms/IndVarSimplify/checks_against_min_value.ll
===================================================================
--- llvm/test/Transforms/IndVarSimplify/checks_against_min_value.ll
+++ llvm/test/Transforms/IndVarSimplify/checks_against_min_value.ll
@@ -15,8 +15,7 @@
 ; CHECK-NEXT:    [[CHECK:%.*]] = icmp slt i32 [[IV_NEXT]], [[IV]]
 ; CHECK-NEXT:    br i1 [[CHECK]], label [[GUARDED]], label [[FAIL:%.*]]
 ; CHECK:       guarded:
-; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ne i32 [[IV]], -2147483648
-; CHECK-NEXT:    br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
+; CHECK-NEXT:    br i1 true, label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
 ; CHECK:       exit.loopexit:
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
@@ -58,8 +57,7 @@
 ; CHECK-NEXT:    [[CHECK:%.*]] = icmp ult i32 [[IV_NEXT]], [[IV]]
 ; CHECK-NEXT:    br i1 [[CHECK]], label [[GUARDED]], label [[FAIL:%.*]]
 ; CHECK:       guarded:
-; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ne i32 [[IV]], 0
-; CHECK-NEXT:    br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
+; CHECK-NEXT:    br i1 true, label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
 ; CHECK:       exit.loopexit:
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
Index: llvm/test/Transforms/IndVarSimplify/eliminate-comparison.ll
===================================================================
--- llvm/test/Transforms/IndVarSimplify/eliminate-comparison.ll
+++ llvm/test/Transforms/IndVarSimplify/eliminate-comparison.ll
@@ -380,7 +380,7 @@
 define void @func_13(i32* %len.ptr) {
 ; CHECK-LABEL: @func_13(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, [[RNG0:!range !.*]]
+; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0:![0-9]+]]
 ; CHECK-NEXT:    [[LEN_IS_ZERO:%.*]] = icmp eq i32 [[LEN]], 0
 ; CHECK-NEXT:    br i1 [[LEN_IS_ZERO]], label [[LEAVE:%.*]], label [[LOOP_PREHEADER:%.*]]
 ; CHECK:       loop.preheader:
@@ -424,7 +424,7 @@
 define void @func_14(i32* %len.ptr) {
 ; CHECK-LABEL: @func_14(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[LEN_IS_ZERO:%.*]] = icmp eq i32 [[LEN]], 0
 ; CHECK-NEXT:    [[LEN_IS_INT_MIN:%.*]] = icmp eq i32 [[LEN]], -2147483648
 ; CHECK-NEXT:    [[NO_ENTRY:%.*]] = or i1 [[LEN_IS_ZERO]], [[LEN_IS_INT_MIN]]
@@ -472,7 +472,7 @@
 define void @func_15(i32* %len.ptr) {
 ; CHECK-LABEL: @func_15(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[LEN_ADD_1:%.*]] = add i32 [[LEN]], 1
 ; CHECK-NEXT:    [[LEN_ADD_1_IS_ZERO:%.*]] = icmp eq i32 [[LEN_ADD_1]], 0
 ; CHECK-NEXT:    br i1 [[LEN_ADD_1_IS_ZERO]], label [[LEAVE:%.*]], label [[LOOP_PREHEADER:%.*]]
@@ -517,7 +517,7 @@
 define void @func_16(i32* %len.ptr) {
 ; CHECK-LABEL: @func_16(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[LEN_ADD_5:%.*]] = add i32 [[LEN]], 5
 ; CHECK-NEXT:    [[ENTRY_COND_0:%.*]] = icmp slt i32 [[LEN]], 2147483643
 ; CHECK-NEXT:    [[ENTRY_COND_1:%.*]] = icmp slt i32 4, [[LEN_ADD_5]]
@@ -624,7 +624,7 @@
 define i1 @func_18(i16* %tmp20, i32* %len.addr) {
 ; CHECK-LABEL: @func_18(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_ADDR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LEN:%.*]] = load i32, i32* [[LEN_ADDR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[TMP18:%.*]] = icmp eq i32 [[LEN]], 0
 ; CHECK-NEXT:    br i1 [[TMP18]], label [[BB2:%.*]], label [[BB0_PREHEADER:%.*]]
 ; CHECK:       bb0.preheader:
@@ -686,7 +686,7 @@
 define void @func_19(i32* %length.ptr) {
 ; CHECK-LABEL: @func_19(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[LENGTH_IS_NONZERO:%.*]] = icmp ne i32 [[LENGTH]], 0
 ; CHECK-NEXT:    br i1 [[LENGTH_IS_NONZERO]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]]
 ; CHECK:       loop.preheader:
@@ -774,7 +774,7 @@
 define void @func_21(i32* %length.ptr) {
 ; CHECK-LABEL: @func_21(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[LIM:%.*]] = sub i32 [[LENGTH]], 1
 ; CHECK-NEXT:    [[ENTRY_COND:%.*]] = icmp sgt i32 [[LENGTH]], 1
 ; CHECK-NEXT:    br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]]
@@ -819,7 +819,7 @@
 define void @func_22(i32* %length.ptr) {
 ; CHECK-LABEL: @func_22(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[ENTRY_COND:%.*]] = icmp sgt i32 [[LENGTH]], 1
 ; CHECK-NEXT:    br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]]
 ; CHECK:       loop.preheader:
@@ -861,7 +861,7 @@
 define void @func_23(i32* %length.ptr) {
 ; CHECK-LABEL: @func_23(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[ENTRY_COND:%.*]] = icmp ult i32 4, [[LENGTH]]
 ; CHECK-NEXT:    br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]]
 ; CHECK:       loop.preheader:
@@ -902,7 +902,7 @@
 define void @func_24(i32* %init.ptr) {
 ; CHECK-LABEL: @func_24(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[INIT:%.*]] = load i32, i32* [[INIT_PTR:%.*]], align 4, [[RNG0]]
+; CHECK-NEXT:    [[INIT:%.*]] = load i32, i32* [[INIT_PTR:%.*]], align 4, !range [[RNG0]]
 ; CHECK-NEXT:    [[ENTRY_COND:%.*]] = icmp ugt i32 [[INIT]], 4
 ; CHECK-NEXT:    br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]]
 ; CHECK:       loop.preheader:
@@ -951,11 +951,9 @@
 ; CHECK-NEXT:    [[C1:%.*]] = icmp ne i32 [[IV]], 0
 ; CHECK-NEXT:    br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]]
 ; CHECK:       checked.1:
-; CHECK-NEXT:    [[C2:%.*]] = icmp ne i32 [[IV]], 0
-; CHECK-NEXT:    br i1 [[C2]], label [[CHECKED_2:%.*]], label [[FAIL]]
+; CHECK-NEXT:    br i1 true, label [[CHECKED_2:%.*]], label [[FAIL]]
 ; CHECK:       checked.2:
-; CHECK-NEXT:    [[C3:%.*]] = icmp ne i32 [[IV]], 0
-; CHECK-NEXT:    br i1 [[C3]], label [[BACKEDGE]], label [[FAIL]]
+; CHECK-NEXT:    br i1 true, label [[BACKEDGE]], label [[FAIL]]
 ; CHECK:       backedge:
 ; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 758394
 ; CHECK-NEXT:    [[LOOP_COND:%.*]] = call i1 @cond_func()
@@ -1003,11 +1001,9 @@
 ; CHECK-NEXT:    [[C1:%.*]] = icmp slt i32 [[IV]], 0
 ; CHECK-NEXT:    br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]]
 ; CHECK:       checked.1:
-; CHECK-NEXT:    [[C2:%.*]] = icmp slt i32 [[IV]], 1
-; CHECK-NEXT:    br i1 [[C2]], label [[CHECKED_2:%.*]], label [[FAIL]]
+; CHECK-NEXT:    br i1 true, label [[CHECKED_2:%.*]], label [[FAIL]]
 ; CHECK:       checked.2:
-; CHECK-NEXT:    [[C3:%.*]] = icmp slt i32 [[IV]], 2
-; CHECK-NEXT:    br i1 [[C3]], label [[BACKEDGE]], label [[FAIL]]
+; CHECK-NEXT:    br i1 true, label [[BACKEDGE]], label [[FAIL]]
 ; CHECK:       backedge:
 ; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 758394
 ; CHECK-NEXT:    [[LOOP_COND:%.*]] = call i1 @cond_func()
Index: llvm/test/Transforms/IndVarSimplify/scev-expander-preserve-lcssa.ll
===================================================================
--- llvm/test/Transforms/IndVarSimplify/scev-expander-preserve-lcssa.ll
+++ llvm/test/Transforms/IndVarSimplify/scev-expander-preserve-lcssa.ll
@@ -116,7 +116,7 @@
 ; CHECK-NEXT:    [[C_2:%.*]] = call i1 @cond()
 ; CHECK-NEXT:    br i1 [[C_2]], label [[IF_END106:%.*]], label [[RETURN_LOOPEXIT:%.*]]
 ; CHECK:       if.end106:
-; CHECK-NEXT:    br i1 false, label [[FOR_BODY84]], label [[RETURN_LOOPEXIT]]
+; CHECK-NEXT:    br i1 true, label [[FOR_BODY84]], label [[RETURN_LOOPEXIT]]
 ; CHECK:       return.loopexit:
 ; CHECK-NEXT:    br label [[RETURN]]
 ; CHECK:       return.loopexit1: