diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -4539,6 +4539,21 @@
   auto *CastOp0 = dyn_cast<CastInst>(ICmp.getOperand(0));
   if (!CastOp0)
     return nullptr;
+
+  // icmp (inttoptr (ptrtoint p1)), p2 --> icmp p1, p2.
+  if (CastOp0->getOpcode() == Instruction::IntToPtr) {
+    if (auto *I = dyn_cast<PtrToIntInst>(CastOp0->getOperand(0))) {
+      Value *P = I->getOperand(0);
+      Type *Op0Ty = CastOp0->getDestTy();
+      Value *NewOp0 = nullptr;
+      if (I->getSrcTy() != Op0Ty)
+        NewOp0 = Builder.CreateBitCast(P, Op0Ty);
+      else
+        NewOp0 = P;
+      return new ICmpInst(ICmp.getPredicate(), NewOp0, ICmp.getOperand(1));
+    }
+  }
+
   if (!isa<Constant>(ICmp.getOperand(1)) && !isa<CastInst>(ICmp.getOperand(1)))
     return nullptr;
 
diff --git a/llvm/test/Transforms/InstCombine/ptr-int-ptr-icmp.ll b/llvm/test/Transforms/InstCombine/ptr-int-ptr-icmp.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/ptr-int-ptr-icmp.ll
@@ -0,0 +1,37 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -instcombine -S  < %s | FileCheck %s
+
+define i1 @func(i8* %X, i8* %Y) {
+; CHECK-LABEL: @func(
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8* [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %i = ptrtoint i8* %X to i64
+  %p = inttoptr i64 %i to i8*
+  %cmp = icmp eq i8* %p, %Y
+  ret i1 %cmp
+}
+
+define i1 @func2(i16* %X, i8* %Y) {
+; CHECK-LABEL: @func2(
+; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i16* [[X:%.*]] to i8*
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8* [[TMP1]], [[Y:%.*]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %i = ptrtoint i16* %X to i64
+  %p = inttoptr i64 %i to i8*
+  %cmp = icmp eq i8* %p, %Y
+  ret i1 %cmp
+}
+
+define i1 @func3(i16* %X, i8* %Y) {
+; CHECK-LABEL: @func3(
+; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i16* [[X:%.*]] to i8*
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8* [[TMP1]], [[Y:%.*]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %i = ptrtoint i16* %X to i64
+  %p = inttoptr i64 %i to i8*
+  %cmp = icmp eq i8* %Y, %p
+  ret i1 %cmp
+}