llvm/test/Transforms/SimplifyCFG/switch-range-to-icmp.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt %s -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-range-to-icmp -S | FileCheck %s

declare i32 @f(i32)

define i32 @basic(i32 %x) {
; CHECK-LABEL: @basic(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT:    br i1 [[SWITCH]], label [[A:%.*]], label [[DEFAULT:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[DEFAULT]] ], [ [[TMP1:%.*]], [[A]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       default:
; CHECK-NEXT:    [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       a:
; CHECK-NEXT:    [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;

entry:
  switch i32 %x, label %default [
  i32 5, label %a
  i32 6, label %a
  i32 7, label %a
  ]
default:
  %0 = call i32 @f(i32 0)
  ret i32 %0
a:
  %1 = call i32 @f(i32 1)
  ret i32 %1
}


define i32 @unreachable(i32 %x) {
; CHECK-LABEL: @unreachable(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT:    br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[A]] ], [ [[TMP1:%.*]], [[B]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       a:
; CHECK-NEXT:    [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       b:
; CHECK-NEXT:    [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;

entry:
  switch i32 %x, label %unreachable [
  i32 5, label %a
  i32 6, label %a
  i32 7, label %a
  i32 10, label %b
  i32 20, label %b
  i32 30, label %b
  i32 40, label %b
  ]
unreachable:
  unreachable
a:
  %0 = call i32 @f(i32 0)
  ret i32 %0
b:
  %1 = call i32 @f(i32 1)
  ret i32 %1
}


define i32 @unreachable2(i32 %x) {
; CHECK-LABEL: @unreachable2(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT:    br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[A]] ], [ [[TMP1:%.*]], [[B]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       a:
; CHECK-NEXT:    [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       b:
; CHECK-NEXT:    [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;

entry:
  ; Note: folding the most popular case destination into the default
  ; would prevent switch-to-icmp here.
  switch i32 %x, label %unreachable [
  i32 5, label %a
  i32 6, label %a
  i32 7, label %a
  i32 10, label %b
  i32 20, label %b
  ]
unreachable:
  unreachable
a:
  %0 = call i32 @f(i32 0)
  ret i32 %0
b:
  %1 = call i32 @f(i32 1)
  ret i32 %1
}

; This would crash because we did not clean up the
; default block of the switch before removing the switch.

define void @PR42737(ptr %a, i1 %c) {
; CHECK-LABEL: @PR42737(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    unreachable
;
entry:
  br i1 %c, label %switch, label %else

else:
  store i32 2, ptr %a
  br label %switch

switch:
  %cleanup.dest1 = phi i32 [ 0, %else ], [ 3, %entry ]
  switch i32 %cleanup.dest1, label %unreach1 [
  i32 0, label %cleanup1
  i32 3, label %cleanup2
  ]

cleanup1:
  br label %unreach2

cleanup2:
  br label %unreach2

unreach1:
  %phi2 = phi i32 [ %cleanup.dest1, %switch ]
  unreachable

unreach2:
  unreachable
}


define void @pr53208_single_reachable_dest(i8 %sw, ptr %p0) {
; CHECK-LABEL: @pr53208_single_reachable_dest(
; CHECK-NEXT:  exit:
; CHECK-NEXT:    call void @bar(ptr [[P0:%.*]])
; CHECK-NEXT:    ret void
;
  switch i8 %sw, label %group3 [
  i8 0, label %group1
  i8 1, label %group1
  i8 2, label %group1
  i8 3, label %group1
  i8 11, label %group1
  i8 12, label %group1
  i8 13, label %group1
  i8 7, label %group1
  i8 17, label %group1
  i8 14, label %group1
  i8 15, label %group1
  i8 4, label %group2
  i8 5, label %group2
  i8 6, label %group2
  i8 8, label %group2
  i8 9, label %group2
  i8 10, label %group2
  ]

group1:
  br label %exit

group2:
  br label %exit

group3:
  br label %exit

exit:
  %phi = phi ptr [ null, %group3 ], [ %p0, %group2 ], [ null, %group1 ]
  call void @bar(ptr %phi)
  ret void
}

define i32 @wrapping_known_range(i8 range(i8 0, 6) %arg) {
; CHECK-LABEL: @wrapping_known_range(
; CHECK-NEXT:    [[ARG_OFF:%.*]] = add i8 [[ARG:%.*]], -1
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i8 [[ARG_OFF]], 3
; CHECK-NEXT:    br i1 [[SWITCH]], label [[ELSE:%.*]], label [[IF:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[I0:%.*]], [[IF]] ], [ [[I1:%.*]], [[ELSE]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       if:
; CHECK-NEXT:    [[I0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       else:
; CHECK-NEXT:    [[I1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
  switch i8 %arg, label %else [
  i8 0, label %if
  i8 4, label %if
  i8 5, label %if
  ]

if:
  %i0 = call i32 @f(i32 0)
  ret i32 %i0

else:
  %i1 = call i32 @f(i32 1)
  ret i32 %i1
}

define i32 @wrapping_known_range_2(i8 range(i8 0, 6) %arg) {
; CHECK-LABEL: @wrapping_known_range_2(
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp eq i8 [[ARG:%.*]], 1
; CHECK-NEXT:    br i1 [[SWITCH]], label [[ELSE:%.*]], label [[IF:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[I0:%.*]], [[IF]] ], [ [[I1:%.*]], [[ELSE]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       if:
; CHECK-NEXT:    [[I0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       else:
; CHECK-NEXT:    [[I1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
  switch i8 %arg, label %else [
  i8 0, label %if
  i8 2, label %if
  i8 3, label %if
  i8 4, label %if
  i8 5, label %if
  ]

if:
  %i0 = call i32 @f(i32 0)
  ret i32 %i0

else:
  %i1 = call i32 @f(i32 1)
  ret i32 %i1
}

define i32 @wrapping_range(i8 %arg) {
; CHECK-LABEL: @wrapping_range(
; CHECK-NEXT:    [[ARG_OFF:%.*]] = add i8 [[ARG:%.*]], -1
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i8 [[ARG_OFF]], -4
; CHECK-NEXT:    br i1 [[SWITCH]], label [[ELSE:%.*]], label [[IF:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[I0:%.*]], [[IF]] ], [ [[I1:%.*]], [[ELSE]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       if:
; CHECK-NEXT:    [[I0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       else:
; CHECK-NEXT:    [[I1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
  switch i8 %arg, label %else [
  i8 0, label %if
  i8 -3, label %if
  i8 -2, label %if
  i8 -1, label %if
  ]

if:
  %i0 = call i32 @f(i32 0)
  ret i32 %i0

else:
  %i1 = call i32 @f(i32 1)
  ret i32 %i1
}

define i8 @wrapping_range_phi(i8 %arg) {
; CHECK-LABEL: @wrapping_range_phi(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ARG_OFF:%.*]] = add i8 [[ARG:%.*]], -1
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp ult i8 [[ARG_OFF]], -2
; CHECK-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[SWITCH]], i8 0, i8 1
; CHECK-NEXT:    ret i8 [[SPEC_SELECT]]
;
entry:
  switch i8 %arg, label %else [
  i8 0, label %if
  i8 -1, label %if
  ]

if:
  %i = phi i8 [ 0, %else ], [ 1, %entry ], [ 1, %entry ]
  ret i8 %i

else:
  br label %if
}

define i32 @no_continuous_wrapping_range(i8 %arg) {
; CHECK-LABEL: @no_continuous_wrapping_range(
; CHECK-NEXT:    switch i8 [[ARG:%.*]], label [[ELSE:%.*]] [
; CHECK-NEXT:      i8 0, label [[IF:%.*]]
; CHECK-NEXT:      i8 -3, label [[IF]]
; CHECK-NEXT:      i8 -1, label [[IF]]
; CHECK-NEXT:    ]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[I0:%.*]], [[IF]] ], [ [[I1:%.*]], [[ELSE]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       if:
; CHECK-NEXT:    [[I0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       else:
; CHECK-NEXT:    [[I1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
  switch i8 %arg, label %else [
  i8 0, label %if
  i8 -3, label %if
  i8 -1, label %if
  ]

if:
  %i0 = call i32 @f(i32 0)
  ret i32 %i0

else:
  %i1 = call i32 @f(i32 1)
  ret i32 %i1
}

define i32 @one_case_1(i32 %x) {
; CHECK-LABEL: @one_case_1(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp eq i32 [[X:%.*]], 10
; CHECK-NEXT:    br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[B]] ], [ [[TMP1:%.*]], [[A]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       a:
; CHECK-NEXT:    [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       b:
; CHECK-NEXT:    [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
entry:
  switch i32 %x, label %unreachable [
  i32 5, label %a
  i32 6, label %a
  i32 7, label %a
  i32 10, label %b
  ]

unreachable:
  unreachable
a:
  %0 = call i32 @f(i32 0)
  ret i32 %0
b:
  %1 = call i32 @f(i32 1)
  ret i32 %1
}

define i32 @one_case_2(i32 %x) {
; CHECK-LABEL: @one_case_2(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[SWITCH:%.*]] = icmp eq i32 [[X:%.*]], 5
; CHECK-NEXT:    br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK:       common.ret:
; CHECK-NEXT:    [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[A]] ], [ [[TMP1:%.*]], [[B]] ]
; CHECK-NEXT:    ret i32 [[COMMON_RET_OP]]
; CHECK:       a:
; CHECK-NEXT:    [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT:    br label [[COMMON_RET:%.*]]
; CHECK:       b:
; CHECK-NEXT:    [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT:    br label [[COMMON_RET]]
;
entry:
  switch i32 %x, label %unreachable [
  i32 5, label %a
  i32 10, label %b
  i32 11, label %b
  i32 12, label %b
  i32 13, label %b
  ]

unreachable:
  unreachable
a:
  %0 = call i32 @f(i32 0)
  ret i32 %0
b:
  %1 = call i32 @f(i32 1)
  ret i32 %1
}

define i32 @else_will_be_unreachable(i1 %arg) {
; CHECK-LABEL: @else_will_be_unreachable(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[I:%.*]] = select i1 [[ARG:%.*]], i32 0, i32 1
; CHECK-NEXT:    ret i32 [[I]]
;
entry:
  switch i1 %arg, label %else [
  i1 false, label %if
  i1 true, label %if
  ]

if:
  br i1 %arg, label %else, label %bb

bb:
  br label %else

else:
  %i = phi i32 [ 0, %entry ], [ 0, %if ], [ 1, %bb ]
  ret i32 %i
}

declare void @bar(ptr nonnull dereferenceable(4))