--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse4.1 | FileCheck %s --check-prefix=SSE
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2 | FileCheck %s --check-prefix=AVX
+
+; fold (add x, 0) -> x
+define <4 x i32> @combine_vec_add_to_zero(<4 x i32> %a) {
+; SSE-LABEL: combine_vec_add_to_zero:
+; SSE: # BB#0:
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_to_zero:
+; AVX: # BB#0:
+; AVX-NEXT: retq
+ %1 = add <4 x i32> %a, zeroinitializer
+ ret <4 x i32> %1
+}
+
+; fold ((c1-A)+c2) -> (c1+c2)-A
+define <4 x i32> @combine_vec_add_constant_sub(<4 x i32> %a) {
+; SSE-LABEL: combine_vec_add_constant_sub:
+; SSE: # BB#0:
+; SSE-NEXT: movdqa {{.*#+}} xmm2 = [0,1,2,3]
+; SSE-NEXT: movdqa %xmm2, %xmm1
+; SSE-NEXT: psubd %xmm0, %xmm1
+; SSE-NEXT: paddd %xmm2, %xmm1
+; SSE-NEXT: movdqa %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_constant_sub:
+; AVX: # BB#0:
+; AVX-NEXT: vmovdqa {{.*#+}} xmm1 = [0,1,2,3]
+; AVX-NEXT: vpsubd %xmm0, %xmm1, %xmm0
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> <i32 0, i32 1, i32 2, i32 3>, %a
+ %2 = add <4 x i32> <i32 0, i32 1, i32 2, i32 3>, %1
+ ret <4 x i32> %2
+}
+
+; fold ((0-A) + B) -> B-A
+define <4 x i32> @combine_vec_add_neg0(<4 x i32> %a, <4 x i32> %b) {
+; SSE-LABEL: combine_vec_add_neg0:
+; SSE: # BB#0:
+; SSE-NEXT: pxor %xmm2, %xmm2
+; SSE-NEXT: psubd %xmm0, %xmm2
+; SSE-NEXT: paddd %xmm1, %xmm2
+; SSE-NEXT: movdqa %xmm2, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_neg0:
+; AVX: # BB#0:
+; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
+; AVX-NEXT: vpsubd %xmm0, %xmm2, %xmm0
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> zeroinitializer, %a
+ %2 = add <4 x i32> %1, %b
+ ret <4 x i32> %2
+}
+
+; fold (A + (0-B)) -> A-B
+define <4 x i32> @combine_vec_add_neg1(<4 x i32> %a, <4 x i32> %b) {
+; SSE-LABEL: combine_vec_add_neg1:
+; SSE: # BB#0:
+; SSE-NEXT: pxor %xmm2, %xmm2
+; SSE-NEXT: psubd %xmm1, %xmm2
+; SSE-NEXT: paddd %xmm2, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_neg1:
+; AVX: # BB#0:
+; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
+; AVX-NEXT: vpsubd %xmm1, %xmm2, %xmm1
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> zeroinitializer, %b
+ %2 = add <4 x i32> %a, %1
+ ret <4 x i32> %2
+}
+
+; fold (A+(B-A)) -> B
+define <4 x i32> @combine_vec_add_sub0(<4 x i32> %a, <4 x i32> %b) {
+; SSE-LABEL: combine_vec_add_sub0:
+; SSE: # BB#0:
+; SSE-NEXT: movaps %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub0:
+; AVX: # BB#0:
+; AVX-NEXT: vmovaps %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> %b, %a
+ %2 = add <4 x i32> %a, %1
+ ret <4 x i32> %2
+}
+
+; fold ((B-A)+A) -> B
+define <4 x i32> @combine_vec_add_sub1(<4 x i32> %a, <4 x i32> %b) {
+; SSE-LABEL: combine_vec_add_sub1:
+; SSE: # BB#0:
+; SSE-NEXT: movaps %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub1:
+; AVX: # BB#0:
+; AVX-NEXT: vmovaps %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> %b, %a
+ %2 = add <4 x i32> %1, %a
+ ret <4 x i32> %2
+}
+
+; fold (A+(B-(A+C))) to (B-C)
+define <4 x i32> @combine_vec_add_sub_add0(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+; SSE-LABEL: combine_vec_add_sub_add0:
+; SSE: # BB#0:
+; SSE-NEXT: psubd %xmm2, %xmm1
+; SSE-NEXT: movdqa %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub_add0:
+; AVX: # BB#0:
+; AVX-NEXT: vpsubd %xmm2, %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = add <4 x i32> %a, %c
+ %2 = sub <4 x i32> %b, %1
+ %3 = add <4 x i32> %a, %2
+ ret <4 x i32> %3
+}
+
+; fold (A+(B-(C+A))) to (B-C)
+define <4 x i32> @combine_vec_add_sub_add1(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+; SSE-LABEL: combine_vec_add_sub_add1:
+; SSE: # BB#0:
+; SSE-NEXT: psubd %xmm2, %xmm1
+; SSE-NEXT: movdqa %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub_add1:
+; AVX: # BB#0:
+; AVX-NEXT: vpsubd %xmm2, %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = add <4 x i32> %c, %a
+ %2 = sub <4 x i32> %b, %1
+ %3 = add <4 x i32> %a, %2
+ ret <4 x i32> %3
+}
+
+; fold (A+((B-A)+C)) to (B+C)
+define <4 x i32> @combine_vec_add_sub_add2(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+; SSE-LABEL: combine_vec_add_sub_add2:
+; SSE: # BB#0:
+; SSE-NEXT: paddd %xmm2, %xmm1
+; SSE-NEXT: movdqa %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub_add2:
+; AVX: # BB#0:
+; AVX-NEXT: vpaddd %xmm2, %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> %b, %a
+ %2 = add <4 x i32> %1, %c
+ %3 = add <4 x i32> %a, %2
+ ret <4 x i32> %3
+}
+
+; fold (A+((B-A)-C)) to (B-C)
+define <4 x i32> @combine_vec_add_sub_add3(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+; SSE-LABEL: combine_vec_add_sub_add3:
+; SSE: # BB#0:
+; SSE-NEXT: psubd %xmm2, %xmm1
+; SSE-NEXT: movdqa %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub_add3:
+; AVX: # BB#0:
+; AVX-NEXT: vpsubd %xmm2, %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> %b, %a
+ %2 = sub <4 x i32> %1, %c
+ %3 = add <4 x i32> %a, %2
+ ret <4 x i32> %3
+}
+
+; fold (A-B)+(C-D) to (A+C)-(B+D) when A or C is constant
+define <4 x i32> @combine_vec_add_sub_sub(<4 x i32> %a, <4 x i32> %b, <4 x i32> %d) {
+; SSE-LABEL: combine_vec_add_sub_sub:
+; SSE: # BB#0:
+; SSE-NEXT: psubd %xmm1, %xmm0
+; SSE-NEXT: movdqa {{.*#+}} xmm1 = [0,1,2,3]
+; SSE-NEXT: psubd %xmm2, %xmm1
+; SSE-NEXT: paddd %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sub_sub:
+; AVX: # BB#0:
+; AVX-NEXT: vpsubd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: vmovdqa {{.*#+}} xmm1 = [0,1,2,3]
+; AVX-NEXT: vpsubd %xmm2, %xmm1, %xmm1
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> %a, %b
+ %2 = sub <4 x i32> <i32 0, i32 1, i32 2, i32 3>, %d
+ %3 = add <4 x i32> %1, %2
+ ret <4 x i32> %3
+}
+
+; fold (a+b) -> (a|b) iff a and b share no bits.
+define <4 x i32> @combine_vec_add_uniquebits(<4 x i32> %a, <4 x i32> %b) {
+; SSE-LABEL: combine_vec_add_uniquebits:
+; SSE: # BB#0:
+; SSE-NEXT: pand {{.*}}(%rip), %xmm0
+; SSE-NEXT: pand {{.*}}(%rip), %xmm1
+; SSE-NEXT: paddd %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_uniquebits:
+; AVX: # BB#0:
+; AVX-NEXT: vpbroadcastd {{.*}}(%rip), %xmm2
+; AVX-NEXT: vpand %xmm2, %xmm0, %xmm0
+; AVX-NEXT: vpbroadcastd {{.*}}(%rip), %xmm2
+; AVX-NEXT: vpand %xmm2, %xmm1, %xmm1
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = and <4 x i32> %a, <i32 61680, i32 61680, i32 61680, i32 61680>
+ %2 = and <4 x i32> %b, <i32 3855, i32 3855, i32 3855, i32 3855>
+ %3 = add <4 x i32> %1, %2
+ ret <4 x i32> %3
+}
+
+; fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n))
+define <4 x i32> @combine_vec_add_shl_neg0(<4 x i32> %x, <4 x i32> %y) {
+; SSE-LABEL: combine_vec_add_shl_neg0:
+; SSE: # BB#0:
+; SSE-NEXT: pxor %xmm2, %xmm2
+; SSE-NEXT: psubd %xmm1, %xmm2
+; SSE-NEXT: pslld $5, %xmm2
+; SSE-NEXT: paddd %xmm2, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_shl_neg0:
+; AVX: # BB#0:
+; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
+; AVX-NEXT: vpsubd %xmm1, %xmm2, %xmm1
+; AVX-NEXT: vpslld $5, %xmm1, %xmm1
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> zeroinitializer, %y
+ %2 = shl <4 x i32> %1, <i32 5, i32 5, i32 5, i32 5>
+ %3 = add <4 x i32> %x, %2
+ ret <4 x i32> %3
+}
+
+; fold (add shl(0 - y, n), x) -> sub(x, shl(y, n))
+define <4 x i32> @combine_vec_add_shl_neg1(<4 x i32> %x, <4 x i32> %y) {
+; SSE-LABEL: combine_vec_add_shl_neg1:
+; SSE: # BB#0:
+; SSE-NEXT: pxor %xmm2, %xmm2
+; SSE-NEXT: psubd %xmm1, %xmm2
+; SSE-NEXT: pslld $5, %xmm2
+; SSE-NEXT: paddd %xmm2, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_shl_neg1:
+; AVX: # BB#0:
+; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
+; AVX-NEXT: vpsubd %xmm1, %xmm2, %xmm1
+; AVX-NEXT: vpslld $5, %xmm1, %xmm1
+; AVX-NEXT: vpaddd %xmm0, %xmm1, %xmm0
+; AVX-NEXT: retq
+ %1 = sub <4 x i32> zeroinitializer, %y
+ %2 = shl <4 x i32> %1, <i32 5, i32 5, i32 5, i32 5>
+ %3 = add <4 x i32> %2, %x
+ ret <4 x i32> %3
+}
+
+; (add z, (and (sbbl x, x), 1)) -> (sub z, (sbbl x, x))
+; and similar xforms where the inner op is either ~0 or 0.
+define <4 x i32> @combine_vec_add_and_compare(<4 x i32> %a0, <4 x i32> %a1, <4 x i32> %a2) {
+; SSE-LABEL: combine_vec_add_and_compare:
+; SSE: # BB#0:
+; SSE-NEXT: pcmpeqd %xmm2, %xmm1
+; SSE-NEXT: psrld $31, %xmm1
+; SSE-NEXT: paddd %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_and_compare:
+; AVX: # BB#0:
+; AVX-NEXT: vpcmpeqd %xmm2, %xmm1, %xmm1
+; AVX-NEXT: vpsrld $31, %xmm1, %xmm1
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = icmp eq <4 x i32> %a1, %a2
+ %2 = sext <4 x i1> %1 to <4 x i32>
+ %3 = and <4 x i32> %2, <i32 1, i32 1, i32 1, i32 1>
+ %4 = add <4 x i32> %a0, %3
+ ret <4 x i32> %4
+}
+
+; add (sext i1), X -> sub X, (zext i1)
+define <4 x i32> @combine_vec_add_sext(<4 x i1> %a0, <4 x i32> %a1) {
+; SSE-LABEL: combine_vec_add_sext:
+; SSE: # BB#0:
+; SSE-NEXT: pslld $31, %xmm0
+; SSE-NEXT: psrad $31, %xmm0
+; SSE-NEXT: paddd %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sext:
+; AVX: # BB#0:
+; AVX-NEXT: vpslld $31, %xmm0, %xmm0
+; AVX-NEXT: vpsrad $31, %xmm0, %xmm0
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = sext <4 x i1> %a0 to <4 x i32>
+ %2 = add <4 x i32> %1, %a1
+ ret <4 x i32> %2
+}
+
+; add (sext i1), X -> sub X, (zext i1)
+define <4 x i32> @combine_vec_add_sextinreg(<4 x i32> %a0, <4 x i32> %a1) {
+; SSE-LABEL: combine_vec_add_sextinreg:
+; SSE: # BB#0:
+; SSE-NEXT: pslld $31, %xmm0
+; SSE-NEXT: psrad $31, %xmm0
+; SSE-NEXT: paddd %xmm1, %xmm0
+; SSE-NEXT: retq
+;
+; AVX-LABEL: combine_vec_add_sextinreg:
+; AVX: # BB#0:
+; AVX-NEXT: vpslld $31, %xmm0, %xmm0
+; AVX-NEXT: vpsrad $31, %xmm0, %xmm0
+; AVX-NEXT: vpaddd %xmm1, %xmm0, %xmm0
+; AVX-NEXT: retq
+ %1 = shl <4 x i32> %a0, <i32 31, i32 31, i32 31, i32 31>
+ %2 = ashr <4 x i32> %1, <i32 31, i32 31, i32 31, i32 31>
+ %3 = add <4 x i32> %2, %a1
+ ret <4 x i32> %3
+}