diff --git a/test/Transforms/InstCombine/assoc-cast-assoc.ll b/test/Transforms/InstCombine/assoc-cast-assoc.ll
new file mode 100644
index 00000000000..ee193112bd6
--- /dev/null
+++ b/test/Transforms/InstCombine/assoc-cast-assoc.ll
@@ -0,0 +1,82 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+define i5 @XorZextXor(i3 %a) {
+; CHECK-LABEL: @XorZextXor(
+; CHECK-NEXT:    [[OP1:%.*]] = xor i3 %a, 3
+; CHECK-NEXT:    [[CAST:%.*]] = zext i3 [[OP1]] to i5
+; CHECK-NEXT:    [[OP2:%.*]] = xor i5 [[CAST]], 12
+; CHECK-NEXT:    ret i5 [[OP2]]
+;
+  %op1 = xor i3 %a, 3
+  %cast = zext i3 %op1 to i5
+  %op2 = xor i5 %cast, 12
+  ret i5 %op2
+}
+
+define <2 x i32> @XorZextXorVec(<2 x i1> %a) {
+; CHECK-LABEL: @XorZextXorVec(
+; CHECK-NEXT:    [[OP1:%.*]] = xor <2 x i1> %a, <i1 true, i1 false>
+; CHECK-NEXT:    [[CAST:%.*]] = zext <2 x i1> [[OP1]] to <2 x i32>
+; CHECK-NEXT:    [[OP2:%.*]] = xor <2 x i32> [[CAST]], <i32 3, i32 1>
+; CHECK-NEXT:    ret <2 x i32> [[OP2]]
+;
+  %op1 = xor <2 x i1> %a, <i1 true, i1 false>
+  %cast = zext <2 x i1> %op1 to <2 x i32>
+  %op2 = xor <2 x i32> %cast, <i32 3, i32 1>
+  ret <2 x i32> %op2
+}
+
+define i5 @OrZextOr(i3 %a) {
+; CHECK-LABEL: @OrZextOr(
+; CHECK-NEXT:    [[OP1:%.*]] = or i3 %a, 3
+; CHECK-NEXT:    [[CAST:%.*]] = zext i3 [[OP1]] to i5
+; CHECK-NEXT:    [[OP2:%.*]] = or i5 [[CAST]], 8
+; CHECK-NEXT:    ret i5 [[OP2]]
+;
+  %op1 = or i3 %a, 3
+  %cast = zext i3 %op1 to i5
+  %op2 = or i5 %cast, 8
+  ret i5 %op2
+}
+
+define <2 x i32> @OrZextOrVec(<2 x i2> %a) {
+; CHECK-LABEL: @OrZextOrVec(
+; CHECK-NEXT:    [[OP1:%.*]] = or <2 x i2> %a, <i2 -2, i2 0>
+; CHECK-NEXT:    [[CAST:%.*]] = zext <2 x i2> [[OP1]] to <2 x i32>
+; CHECK-NEXT:    [[OP2:%.*]] = or <2 x i32> [[CAST]], <i32 1, i32 5>
+; CHECK-NEXT:    ret <2 x i32> [[OP2]]
+;
+  %op1 = or <2 x i2> %a, <i2 2, i2 0>
+  %cast = zext <2 x i2> %op1 to <2 x i32>
+  %op2 = or <2 x i32> %cast, <i32 1, i32 5>
+  ret <2 x i32> %op2
+}
+
+; Unlike the rest, this case is handled by SimplifyDemandedBits / ShrinkDemandedConstant.
+
+define i5 @AndZextAnd(i3 %a) {
+; CHECK-LABEL: @AndZextAnd(
+; CHECK-NEXT:    [[CAST:%.*]] = zext i3 %a to i5
+; CHECK-NEXT:    [[OP2:%.*]] = and i5 [[CAST]], 2
+; CHECK-NEXT:    ret i5 [[OP2]]
+;
+  %op1 = and i3 %a, 3
+  %cast = zext i3 %op1 to i5
+  %op2 = and i5 %cast, 14
+  ret i5 %op2
+}
+
+define <2 x i32> @AndZextAndVec(<2 x i8> %a) {
+; CHECK-LABEL: @AndZextAndVec(
+; CHECK-NEXT:    [[OP1:%.*]] = and <2 x i8> %a, <i8 7, i8 0>
+; CHECK-NEXT:    [[CAST:%.*]] = zext <2 x i8> [[OP1]] to <2 x i32>
+; CHECK-NEXT:    [[OP2:%.*]] = and <2 x i32> [[CAST]], <i32 261, i32 1>
+; CHECK-NEXT:    ret <2 x i32> [[OP2]]
+;
+  %op1 = and <2 x i8> %a, <i8 7, i8 0>
+  %cast = zext <2 x i8> %op1 to <2 x i32>
+  %op2 = and <2 x i32> %cast, <i32 261, i32 1>
+  ret <2 x i32> %op2
+}
+