llvm/test/Transforms/InstCombine/icmp-fsh.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s

declare i8 @llvm.fshl.i8(i8, i8, i8)
declare i8 @llvm.fshr.i8(i8, i8, i8)
declare <2 x i5> @llvm.fshl.v2i5(<2 x i5>, <2 x i5>, <2 x i5>)
declare void @use(i8)

define i1 @rotl_eq_0(i8 %x, i8 %y) {
; CHECK-LABEL: @rotl_eq_0(
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshl.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp eq i8 %rot, 0
  ret i1 %r
}

; Extra use is ok.

define i1 @rotl_ne_0(i8 %x, i8 %y) {
; CHECK-LABEL: @rotl_ne_0(
; CHECK-NEXT:    [[ROT:%.*]] = tail call i8 @llvm.fshl.i8(i8 [[X:%.*]], i8 [[X]], i8 [[Y:%.*]])
; CHECK-NEXT:    call void @use(i8 [[ROT]])
; CHECK-NEXT:    [[R:%.*]] = icmp ne i8 [[X]], 0
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshl.i8(i8 %x, i8 %x, i8 %y)
  call void @use(i8 %rot)
  %r = icmp ne i8 %rot, 0
  ret i1 %r
}

define i1 @rotl_eq_n1(i8 %x, i8 %y) {
; CHECK-LABEL: @rotl_eq_n1(
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[X:%.*]], -1
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshl.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp eq i8 %rot, -1
  ret i1 %r
}

; Vectors work too.

define <2 x i1> @rotl_ne_n1(<2 x i5> %x, <2 x i5> %y) {
; CHECK-LABEL: @rotl_ne_n1(
; CHECK-NEXT:    [[R:%.*]] = icmp ne <2 x i5> [[X:%.*]], <i5 -1, i5 -1>
; CHECK-NEXT:    ret <2 x i1> [[R]]
;
  %rot = tail call <2 x i5> @llvm.fshl.v2i5(<2 x i5>%x, <2 x i5> %x, <2 x i5> %y)
  %r = icmp ne <2 x i5> %rot, <i5 -1, i5 -1>
  ret <2 x i1> %r
}

; TODO: We filter out vector constants with undef elts, but that isn't needed for this transform.

define <2 x i1> @rotl_ne_n1_undef(<2 x i5> %x, <2 x i5> %y) {
; CHECK-LABEL: @rotl_ne_n1_undef(
; CHECK-NEXT:    [[ROT:%.*]] = tail call <2 x i5> @llvm.fshl.v2i5(<2 x i5> [[X:%.*]], <2 x i5> [[X]], <2 x i5> [[Y:%.*]])
; CHECK-NEXT:    [[R:%.*]] = icmp ne <2 x i5> [[ROT]], <i5 -1, i5 undef>
; CHECK-NEXT:    ret <2 x i1> [[R]]
;
  %rot = tail call <2 x i5> @llvm.fshl.v2i5(<2 x i5>%x, <2 x i5> %x, <2 x i5> %y)
  %r = icmp ne <2 x i5> %rot, <i5 -1, i5 undef>
  ret <2 x i1> %r
}

define i1 @rotr_eq_0(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_eq_0(
; CHECK-NEXT:    [[ROT:%.*]] = tail call i8 @llvm.fshr.i8(i8 [[X:%.*]], i8 [[X]], i8 [[Y:%.*]])
; CHECK-NEXT:    call void @use(i8 [[ROT]])
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[X]], 0
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  call void @use(i8 %rot)
  %r = icmp eq i8 %rot, 0
  ret i1 %r
}

define i1 @rotr_ne_0(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_ne_0(
; CHECK-NEXT:    [[R:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp ne i8 %rot, 0
  ret i1 %r
}

define i1 @rotr_eq_n1(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_eq_n1(
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[X:%.*]], -1
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp eq i8 %rot, -1
  ret i1 %r
}

define i1 @rotr_ne_n1(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_ne_n1(
; CHECK-NEXT:    [[R:%.*]] = icmp ne i8 [[X:%.*]], -1
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp ne i8 %rot, -1
  ret i1 %r
}

; negative test - wrong constant value

define i1 @rotr_ne_1(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_ne_1(
; CHECK-NEXT:    [[ROT:%.*]] = tail call i8 @llvm.fshr.i8(i8 [[X:%.*]], i8 [[X]], i8 [[Y:%.*]])
; CHECK-NEXT:    [[R:%.*]] = icmp ne i8 [[ROT]], 1
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp ne i8 %rot, 1
  ret i1 %r
}

; negative test - wrong predicate

define i1 @rotr_sgt_n1(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_sgt_n1(
; CHECK-NEXT:    [[ROT:%.*]] = tail call i8 @llvm.fshr.i8(i8 [[X:%.*]], i8 [[X]], i8 [[Y:%.*]])
; CHECK-NEXT:    [[R:%.*]] = icmp sgt i8 [[ROT]], -1
; CHECK-NEXT:    ret i1 [[R]]
;
  %rot = tail call i8 @llvm.fshr.i8(i8 %x, i8 %x, i8 %y)
  %r = icmp sgt i8 %rot, -1
  ret i1 %r
}

; negative test - must be a rotate, not general funnel shift

define i1 @fshr_sgt_n1(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @fshr_sgt_n1(
; CHECK-NEXT:    [[FSH:%.*]] = tail call i8 @llvm.fshr.i8(i8 [[X:%.*]], i8 [[Y:%.*]], i8 [[Z:%.*]])
; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[FSH]], -1
; CHECK-NEXT:    ret i1 [[R]]
;
  %fsh = tail call i8 @llvm.fshr.i8(i8 %x, i8 %y, i8 %z)
  %r = icmp eq i8 %fsh, -1
  ret i1 %r
}