llvm/llvm/test/CodeGen/X86/combine-sub-ssat.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse2 | FileCheck %s --check-prefixes=CHECK,SSE
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse4.1 | FileCheck %s --check-prefixes=CHECK,SSE
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse4.2 | FileCheck %s --check-prefixes=CHECK,SSE
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx | FileCheck %s --check-prefixes=CHECK,AVX
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2 | FileCheck %s --check-prefixes=CHECK,AVX
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512f | FileCheck %s --check-prefixes=CHECK,AVX
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512bw | FileCheck %s --check-prefixes=CHECK,AVX

declare  i32 @llvm.ssub.sat.i32  (i32, i32)
declare  i64 @llvm.ssub.sat.i64  (i64, i64)
declare  <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16>, <8 x i16>)

; fold (ssub_sat x, undef) -> 0
define i32 @combine_undef_i32(i32 %a0) {
; CHECK-LABEL: combine_undef_i32:
; CHECK:       # %bb.0:
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    retq
  %res = call i32 @llvm.ssub.sat.i32(i32 %a0, i32 undef)
  ret i32 %res
}

define <8 x i16> @combine_undef_v8i16(<8 x i16> %a0) {
; SSE-LABEL: combine_undef_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    xorps %xmm0, %xmm0
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_undef_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vxorps %xmm0, %xmm0, %xmm0
; AVX-NEXT:    retq
  %res = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> undef, <8 x i16> %a0)
  ret <8 x i16> %res
}

; fold (ssub_sat c1, c2) -> c3
define i32 @combine_constfold_i32() {
; CHECK-LABEL: combine_constfold_i32:
; CHECK:       # %bb.0:
; CHECK-NEXT:    movl $-2147483547, %eax # imm = 0x80000065
; CHECK-NEXT:    retq
  %res = call i32 @llvm.ssub.sat.i32(i32 100, i32 2147483647)
  ret i32 %res
}

define <8 x i16> @combine_constfold_v8i16() {
; SSE-LABEL: combine_constfold_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    movaps {{.*#+}} xmm0 = [65535,2,254,0,65534,65282,32786,2]
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_constfold_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vmovaps {{.*#+}} xmm0 = [65535,2,254,0,65534,65282,32786,2]
; AVX-NEXT:    retq
  %res = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> <i16 0, i16 1, i16 255, i16 65535, i16 -1, i16 -255, i16 -32760, i16 1>, <8 x i16> <i16 1, i16 65535, i16 1, i16 65535, i16 1, i16 65535, i16 -10, i16 65535>)
  ret <8 x i16> %res
}

define <8 x i16> @combine_constfold_undef_v8i16() {
; SSE-LABEL: combine_constfold_undef_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    movaps {{.*#+}} xmm0 = [0,0,0,0,65534,65282,32786,2]
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_constfold_undef_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vmovaps {{.*#+}} xmm0 = [0,0,0,0,65534,65282,32786,2]
; AVX-NEXT:    retq
  %res = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> <i16 undef, i16 1, i16 undef, i16 65535, i16 -1, i16 -255, i16 -32760, i16 1>, <8 x i16> <i16 1, i16 undef, i16 undef, i16 65535, i16 1, i16 65535, i16 -10, i16 65535>)
  ret <8 x i16> %res
}

; fold (ssub_sat x, 0) -> x
define i32 @combine_zero_i32(i32 %a0) {
; CHECK-LABEL: combine_zero_i32:
; CHECK:       # %bb.0:
; CHECK-NEXT:    movl %edi, %eax
; CHECK-NEXT:    retq
  %1 = call i32 @llvm.ssub.sat.i32(i32 %a0, i32 0)
  ret i32 %1
}

define <8 x i16> @combine_zero_v8i16(<8 x i16> %a0) {
; CHECK-LABEL: combine_zero_v8i16:
; CHECK:       # %bb.0:
; CHECK-NEXT:    retq
  %1 = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> %a0, <8 x i16> zeroinitializer)
  ret <8 x i16> %1
}

; fold (ssub_sat x, x) -> 0
define i32 @combine_self_i32(i32 %a0) {
; CHECK-LABEL: combine_self_i32:
; CHECK:       # %bb.0:
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    retq
  %1 = call i32 @llvm.ssub.sat.i32(i32 %a0, i32 %a0)
  ret i32 %1
}

define <8 x i16> @combine_self_v8i16(<8 x i16> %a0) {
; SSE-LABEL: combine_self_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    xorps %xmm0, %xmm0
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_self_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vxorps %xmm0, %xmm0, %xmm0
; AVX-NEXT:    retq
  %1 = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> %a0, <8 x i16> %a0)
  ret <8 x i16> %1
}

; fold (ssub_sat x, y) -> (sub x, y) iff no overflow
define i32 @combine_no_overflow_i32(i32 %a0, i32 %a1) {
; CHECK-LABEL: combine_no_overflow_i32:
; CHECK:       # %bb.0:
; CHECK-NEXT:    movl %edi, %eax
; CHECK-NEXT:    sarl $16, %eax
; CHECK-NEXT:    shrl $16, %esi
; CHECK-NEXT:    subl %esi, %eax
; CHECK-NEXT:    retq
  %1 = ashr i32 %a0, 16
  %2 = lshr i32 %a1, 16
  %3 = call i32 @llvm.ssub.sat.i32(i32 %1, i32 %2)
  ret i32 %3
}

define <8 x i16> @combine_no_overflow_v8i16(<8 x i16> %a0, <8 x i16> %a1) {
; SSE-LABEL: combine_no_overflow_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    psraw $10, %xmm0
; SSE-NEXT:    psrlw $10, %xmm1
; SSE-NEXT:    psubw %xmm1, %xmm0
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_no_overflow_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vpsraw $10, %xmm0, %xmm0
; AVX-NEXT:    vpsrlw $10, %xmm1, %xmm1
; AVX-NEXT:    vpsubw %xmm1, %xmm0, %xmm0
; AVX-NEXT:    retq
  %1 = ashr <8 x i16> %a0, <i16 10, i16 10, i16 10, i16 10, i16 10, i16 10, i16 10, i16 10>
  %2 = lshr <8 x i16> %a1, <i16 10, i16 10, i16 10, i16 10, i16 10, i16 10, i16 10, i16 10>
  %3 = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> %1, <8 x i16> %2)
  ret <8 x i16> %3
}

; fold (ssub_sat (shuffle x, u, m), (shuffle y, u, m)) -> (shuffle (ssub_sat x, y), u, m)
define <8 x i16> @combine_shuffle_shuffle_v8i16(<8 x i16> %x0, <8 x i16> %y0) {
; SSE-LABEL: combine_shuffle_shuffle_v8i16:
; SSE:       # %bb.0:
; SSE-NEXT:    psubsw %xmm1, %xmm0
; SSE-NEXT:    pshuflw {{.*#+}} xmm0 = xmm0[3,2,1,0,4,5,6,7]
; SSE-NEXT:    retq
;
; AVX-LABEL: combine_shuffle_shuffle_v8i16:
; AVX:       # %bb.0:
; AVX-NEXT:    vpsubsw %xmm1, %xmm0, %xmm0
; AVX-NEXT:    vpshuflw {{.*#+}} xmm0 = xmm0[3,2,1,0,4,5,6,7]
; AVX-NEXT:    retq
  %x1= shufflevector <8 x i16> %x0, <8 x i16> poison, <8 x i32> <i32 3, i32 2, i32 1, i32 0, i32 4, i32 5, i32 6, i32 7>
  %y1 = shufflevector <8 x i16> %y0, <8 x i16> poison, <8 x i32> <i32 3, i32 2, i32 1, i32 0, i32 4, i32 5, i32 6, i32 7>
  %res = tail call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> %x1, <8 x i16> %y1)
  ret <8 x i16> %res
}