; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
; RUN: opt -passes=loop-idiom -mtriple=aarch64 < %s -S | FileCheck %s

; Recognize CTLZ builtin pattern.
; Here we'll just convert loop to countable,
; so do not insert builtin if CPU do not support CTLZ
;
; int ctlz_and_other(int n, char *a)
; {
;   n = n >= 0 ? n : -n;
;   int i = 0, n0 = n;
;   while(n >>= 1) {
;     a[i] = (n0 & (1 << i)) ? 1 : 0;
;     i++;
;   }
;   return i;
; }
;

; Function Attrs: norecurse nounwind uwtable
define i32 @ctlz_and_other(i32 %n, ptr nocapture %a) {
; CHECK-LABEL: define i32 @ctlz_and_other(
; CHECK-SAME: i32 [[N:%.*]], ptr captures(none) [[A:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS_N:%.*]] = call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[SHR8:%.*]] = lshr i32 [[ABS_N]], 1
; CHECK-NEXT:    [[TOBOOL9:%.*]] = icmp eq i32 [[SHR8]], 0
; CHECK-NEXT:    br i1 [[TOBOOL9]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = call i32 @llvm.ctlz.i32(i32 [[SHR8]], i1 true)
; CHECK-NEXT:    [[TMP1:%.*]] = sub i32 32, [[TMP0]]
; CHECK-NEXT:    [[TMP2:%.*]] = zext i32 [[TMP1]] to i64
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP1]], [[WHILE_BODY_PREHEADER]] ], [ [[TCDEC:%.*]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR11:%.*]] = phi i32 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[SHR8]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[TMP3:%.*]] = trunc i64 [[INDVARS_IV]] to i32
; CHECK-NEXT:    [[SHL:%.*]] = shl i32 1, [[TMP3]]
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[SHL]], [[ABS_N]]
; CHECK-NEXT:    [[TOBOOL1:%.*]] = icmp ne i32 [[AND]], 0
; CHECK-NEXT:    [[CONV:%.*]] = zext i1 [[TOBOOL1]] to i8
; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT:    store i8 [[CONV]], ptr [[ARRAYIDX]], align 1
; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw i64 [[INDVARS_IV]], 1
; CHECK-NEXT:    [[SHR]] = ashr i32 [[SHR11]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INDVARS_IV_NEXT_LCSSA:%.*]] = phi i64 [ [[TMP2]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[TMP4:%.*]] = trunc i64 [[INDVARS_IV_NEXT_LCSSA]] to i32
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP4]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs_n = call i32 @llvm.abs.i32(i32 %n, i1 true)
  %shr8 = lshr i32 %abs_n, 1
  %tobool9 = icmp eq i32 %shr8, 0
  br i1 %tobool9, label %while.end, label %while.body.preheader

while.body.preheader:                             ; preds = %entry
  br label %while.body

while.body:                                       ; preds = %while.body.preheader, %while.body
  %indvars.iv = phi i64 [ %indvars.iv.next, %while.body ], [ 0, %while.body.preheader ]
  %shr11 = phi i32 [ %shr, %while.body ], [ %shr8, %while.body.preheader ]
  %0 = trunc i64 %indvars.iv to i32
  %shl = shl i32 1, %0
  %and = and i32 %shl, %abs_n
  %tobool1 = icmp ne i32 %and, 0
  %conv = zext i1 %tobool1 to i8
  %arrayidx = getelementptr inbounds i8, ptr %a, i64 %indvars.iv
  store i8 %conv, ptr %arrayidx, align 1
  %indvars.iv.next = add nuw i64 %indvars.iv, 1
  %shr = ashr i32 %shr11, 1
  %tobool = icmp eq i32 %shr, 0
  br i1 %tobool, label %while.end.loopexit, label %while.body

while.end.loopexit:                               ; preds = %while.body
  %1 = trunc i64 %indvars.iv.next to i32
  br label %while.end

while.end:                                        ; preds = %while.end.loopexit, %entry
  %i.0.lcssa = phi i32 [ 0, %entry ], [ %1, %while.end.loopexit ]
  ret i32 %i.0.lcssa
}

; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz_zero_check(int n)
; {
;   n = n >= 0 ? n : -n;
;   int i = 0;
;   while(n) {
;     n >>= 1;
;     i++;
;   }
;   return i;
; }
;

; Function Attrs: norecurse nounwind readnone uwtable
define i32 @ctlz_zero_check(i32 %n) {
; CHECK-LABEL: define i32 @ctlz_zero_check(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS_N:%.*]] = call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[TOBOOL4:%.*]] = icmp eq i32 [[ABS_N]], 0
; CHECK-NEXT:    br i1 [[TOBOOL4]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = call i32 @llvm.ctlz.i32(i32 [[ABS_N]], i1 true)
; CHECK-NEXT:    [[TMP1:%.*]] = sub i32 32, [[TMP0]]
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP1]], [[WHILE_BODY_PREHEADER]] ], [ [[TCDEC:%.*]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[I_06:%.*]] = phi i32 [ [[INC:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[N_ADDR_05:%.*]] = phi i32 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[ABS_N]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = ashr i32 [[N_ADDR_05]], 1
; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_06]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[TMP1]], [[WHILE_BODY]] ]
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC_LCSSA]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs_n = call i32 @llvm.abs.i32(i32 %n, i1 true)
  %tobool4 = icmp eq i32 %abs_n, 0
  br i1 %tobool4, label %while.end, label %while.body.preheader

while.body.preheader:                             ; preds = %entry
  br label %while.body

while.body:                                       ; preds = %while.body.preheader, %while.body
  %i.06 = phi i32 [ %inc, %while.body ], [ 0, %while.body.preheader ]
  %n.addr.05 = phi i32 [ %shr, %while.body ], [ %abs_n, %while.body.preheader ]
  %shr = ashr i32 %n.addr.05, 1
  %inc = add nsw i32 %i.06, 1
  %tobool = icmp eq i32 %shr, 0
  br i1 %tobool, label %while.end.loopexit, label %while.body

while.end.loopexit:                               ; preds = %while.body
  br label %while.end

while.end:                                        ; preds = %while.end.loopexit, %entry
  %i.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.end.loopexit ]
  ret i32 %i.0.lcssa
}

; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz(int n)
; {
;   n = n >= 0 ? n : -n;
;   int i = 0;
;   while(n >>= 1) {
;     i++;
;   }
;   return i;
; }
;

; Function Attrs: norecurse nounwind readnone uwtable
define i32 @ctlz(i32 %n) {
; CHECK-LABEL: define i32 @ctlz(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS_N:%.*]] = call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[TMP0:%.*]] = ashr i32 [[ABS_N]], 1
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[TMP0]], i1 false)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    br label [[WHILE_COND:%.*]]
; CHECK:       while.cond:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[ENTRY:%.*]] ], [ [[TCDEC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[ABS_N]], [[ENTRY]] ], [ [[SHR:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[SHR]] = ashr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END:%.*]], label [[WHILE_COND]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ [[TMP2]], [[WHILE_COND]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs_n = call i32 @llvm.abs.i32(i32 %n, i1 true)
  br label %while.cond

while.cond:                                       ; preds = %while.cond, %entry
  %n.addr.0 = phi i32 [ %abs_n, %entry ], [ %shr, %while.cond ]
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %while.cond ]
  %shr = ashr i32 %n.addr.0, 1
  %tobool = icmp eq i32 %shr, 0
  %inc = add nsw i32 %i.0, 1
  br i1 %tobool, label %while.end, label %while.cond

while.end:                                        ; preds = %while.cond
  ret i32 %i.0
}

; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; This test covers how instcombine may optimise the previous ctlz case.
;
; int ctlz(int n)
; {
;   n = n >= 0 ? n : -n;
;   int i = 0;
;   while(n >>= 1) {
;     i++;
;   }
;   return i;
; }

define i32 @ctlz_fold(i32 noundef %n) {
; CHECK-LABEL: define i32 @ctlz_fold(
; CHECK-SAME: i32 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[COND:%.*]] = tail call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[TOBOOL_NOT5:%.*]] = icmp ult i32 [[COND]], 2
; CHECK-NEXT:    br i1 [[TOBOOL_NOT5]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[COND]], i1 true)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = sub i32 [[TMP2]], 1
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[WHILE_BODY_PREHEADER]] ], [ [[TCDEC:%.*]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[I_07:%.*]] = phi i32 [ [[INC:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[N_ADDR_06:%.*]] = phi i32 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[COND]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = lshr i32 [[N_ADDR_06]], 1
; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_07]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[TOBOOL_NOT]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[TMP3]], [[WHILE_BODY]] ]
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC_LCSSA]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %cond = tail call i32 @llvm.abs.i32(i32 %n, i1 true)
  %tobool.not5 = icmp ult i32 %cond, 2
  br i1 %tobool.not5, label %while.end, label %while.body.preheader

while.body.preheader:                             ; preds = %entry
  br label %while.body

while.body:                                       ; preds = %while.body.preheader, %while.body
  %i.07 = phi i32 [ %inc, %while.body ], [ 0, %while.body.preheader ]
  %n.addr.06 = phi i32 [ %shr, %while.body ], [ %cond, %while.body.preheader ]
  %shr = lshr i32 %n.addr.06, 1
  %inc = add nuw nsw i32 %i.07, 1
  %tobool.not = icmp ult i32 %n.addr.06, 4
  br i1 %tobool.not, label %while.end.loopexit, label %while.body

while.end.loopexit:                               ; preds = %while.body
  %inc.lcssa = phi i32 [ %inc, %while.body ]
  br label %while.end

while.end:                                        ; preds = %while.end.loopexit, %entry
  %i.0.lcssa = phi i32 [ 0, %entry ], [ %inc.lcssa, %while.end.loopexit ]
  ret i32 %i.0.lcssa
}

; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz_add(int n, int i0)
; {
;   n = n >= 0 ? n : -n;
;   int i = i0;
;   while(n >>= 1) {
;     i++;
;   }
;   return i;
; }
;
;
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @ctlz_add(i32 %n, i32 %i0) {
; CHECK-LABEL: define i32 @ctlz_add(
; CHECK-SAME: i32 [[N:%.*]], i32 [[I0:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS_N:%.*]] = call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[TMP0:%.*]] = ashr i32 [[ABS_N]], 1
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[TMP0]], i1 false)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    [[TMP4:%.*]] = add i32 [[TMP2]], [[I0]]
; CHECK-NEXT:    br label [[WHILE_COND:%.*]]
; CHECK:       while.cond:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[ENTRY:%.*]] ], [ [[TCDEC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[ABS_N]], [[ENTRY]] ], [ [[SHR:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ [[I0]], [[ENTRY]] ], [ [[INC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[SHR]] = ashr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END:%.*]], label [[WHILE_COND]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ [[TMP4]], [[WHILE_COND]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs_n = call i32 @llvm.abs.i32(i32 %n, i1 true)
  br label %while.cond

while.cond:                                       ; preds = %while.cond, %entry
  %n.addr.0 = phi i32 [ %abs_n, %entry ], [ %shr, %while.cond ]
  %i.0 = phi i32 [ %i0, %entry ], [ %inc, %while.cond ]
  %shr = ashr i32 %n.addr.0, 1
  %tobool = icmp eq i32 %shr, 0
  %inc = add nsw i32 %i.0, 1
  br i1 %tobool, label %while.end, label %while.cond

while.end:                                        ; preds = %while.cond
  ret i32 %i.0
}


; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz_sub(int n, int i0)
; {
;   n = n >= 0 ? n : -n;
;   int i = i0;
;   while(n >>= 1) {
;     i--;
;   }
;   return i;
; }
;
;
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @ctlz_sub(i32 %n, i32 %i0) {
; CHECK-LABEL: define i32 @ctlz_sub(
; CHECK-SAME: i32 [[N:%.*]], i32 [[I0:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS_N:%.*]] = call i32 @llvm.abs.i32(i32 [[N]], i1 true)
; CHECK-NEXT:    [[TMP0:%.*]] = ashr i32 [[ABS_N]], 1
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[TMP0]], i1 false)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    [[TMP4:%.*]] = sub i32 [[I0]], [[TMP2]]
; CHECK-NEXT:    br label [[WHILE_COND:%.*]]
; CHECK:       while.cond:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[ENTRY:%.*]] ], [ [[TCDEC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[ABS_N]], [[ENTRY]] ], [ [[SHR:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ [[I0]], [[ENTRY]] ], [ [[INC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[SHR]] = ashr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], -1
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END:%.*]], label [[WHILE_COND]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ [[TMP4]], [[WHILE_COND]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs_n = call i32 @llvm.abs.i32(i32 %n, i1 true)
  br label %while.cond

while.cond:                                       ; preds = %while.cond, %entry
  %n.addr.0 = phi i32 [ %abs_n, %entry ], [ %shr, %while.cond ]
  %i.0 = phi i32 [ %i0, %entry ], [ %inc, %while.cond ]
  %shr = ashr i32 %n.addr.0, 1
  %tobool = icmp eq i32 %shr, 0
  %inc = add nsw i32 %i.0, -1
  br i1 %tobool, label %while.end, label %while.cond

while.end:                                        ; preds = %while.cond
  ret i32 %i.0
}


; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz_sext(short in)
; {
;   int n = in;
;   if (in < 0)
;     n = -n;
;   int i = 0;
;   while(n >>= 1) {
;     i++;
;   }
;   return i;
; }
;

; Function Attrs: norecurse nounwind readnone uwtable
define i32 @ctlz_sext(i16 %in) {
; CHECK-LABEL: define i32 @ctlz_sext(
; CHECK-SAME: i16 [[IN:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ABS:%.*]] = call i16 @llvm.abs.i16(i16 [[IN]], i1 false)
; CHECK-NEXT:    [[ABS_N:%.*]] = zext i16 [[ABS]] to i32
; CHECK-NEXT:    [[TMP0:%.*]] = ashr i32 [[ABS_N]], 1
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[TMP0]], i1 false)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    br label [[WHILE_COND:%.*]]
; CHECK:       while.cond:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[ENTRY:%.*]] ], [ [[TCDEC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[ABS_N]], [[ENTRY]] ], [ [[SHR:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC:%.*]], [[WHILE_COND]] ]
; CHECK-NEXT:    [[SHR]] = ashr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[WHILE_END:%.*]], label [[WHILE_COND]]
; CHECK:       while.end:
; CHECK-NEXT:    [[I_0_LCSSA:%.*]] = phi i32 [ [[TMP2]], [[WHILE_COND]] ]
; CHECK-NEXT:    ret i32 [[I_0_LCSSA]]
;
entry:
  %abs = call i16 @llvm.abs.i16(i16 %in, i1 false)
  %abs_n = zext i16 %abs to i32
  br label %while.cond

while.cond:                                       ; preds = %while.cond, %entry
  %n.addr.0 = phi i32 [ %abs_n, %entry ], [ %shr, %while.cond ]
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %while.cond ]
  %shr = ashr i32 %n.addr.0, 1
  %tobool = icmp eq i32 %shr, 0
  %inc = add nsw i32 %i.0, 1
  br i1 %tobool, label %while.end, label %while.cond

while.end:                                        ; preds = %while.cond
  ret i32 %i.0
}


; unsigned floor_log2(unsigned long n) {
;   unsigned result = 0;
;   while (n >>= 1) result++;
;   return result;
; }

define i32 @floor_log2_use_inc(i64 noundef %n) {
; CHECK-LABEL: define i32 @floor_log2_use_inc(
; CHECK-SAME: i64 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TOBOOL_NOT2:%.*]] = icmp ult i64 [[N]], 2
; CHECK-NEXT:    br i1 [[TOBOOL_NOT2]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP1:%.*]] = call i64 @llvm.ctlz.i64(i64 [[N]], i1 true)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i64 64, [[TMP1]]
; CHECK-NEXT:    [[TMP4:%.*]] = sub i64 [[TMP2]], 1
; CHECK-NEXT:    [[TMP3:%.*]] = trunc i64 [[TMP4]] to i32
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i64 [ [[TMP4]], [[WHILE_BODY_PREHEADER]] ], [ [[TCDEC:%.*]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[RESULT_04:%.*]] = phi i32 [ [[INC:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[N_ADDR_03:%.*]] = phi i64 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[N]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = lshr i64 [[N_ADDR_03]], 1
; CHECK-NEXT:    [[INC]] = add i32 [[RESULT_04]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i64 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp eq i64 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[TOBOOL_NOT]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[TMP3]], [[WHILE_BODY]] ]
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[RESULT_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC_LCSSA]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[RESULT_0_LCSSA]]
;
entry:
  %tobool.not2 = icmp ult i64 %n, 2
  br i1 %tobool.not2, label %while.end, label %while.body.preheader

while.body.preheader:
  br label %while.body

while.body:
  %result.04 = phi i32 [ %inc, %while.body ], [ 0, %while.body.preheader ]
  %n.addr.03 = phi i64 [ %shr, %while.body ], [ %n, %while.body.preheader ]
  %shr = lshr i64 %n.addr.03, 1
  %inc = add i32 %result.04, 1
  %tobool.not = icmp ult i64 %n.addr.03, 4
  br i1 %tobool.not, label %while.end.loopexit, label %while.body

while.end.loopexit:
  %inc.lcssa = phi i32 [ %inc, %while.body ]
  br label %while.end

while.end:
  %result.0.lcssa = phi i32 [ 0, %entry ], [ %inc.lcssa, %while.end.loopexit ]
  ret i32 %result.0.lcssa
}


define i32 @floor_log2_use_phi(i64 noundef %n) {
; CHECK-LABEL: define i32 @floor_log2_use_phi(
; CHECK-SAME: i64 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TOBOOL_NOT2:%.*]] = icmp ult i64 [[N]], 2
; CHECK-NEXT:    br i1 [[TOBOOL_NOT2]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[RESULT_04:%.*]] = phi i32 [ [[INC:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[N_ADDR_03:%.*]] = phi i64 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[N]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = lshr i64 [[N_ADDR_03]], 1
; CHECK-NEXT:    [[INC]] = add i32 [[RESULT_04]], 1
; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp ult i64 [[N_ADDR_03]], 4
; CHECK-NEXT:    br i1 [[TOBOOL_NOT]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[RESULT_04]], [[WHILE_BODY]] ]
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[RESULT_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC_LCSSA]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[RESULT_0_LCSSA]]
;
entry:
  %tobool.not2 = icmp ult i64 %n, 2
  br i1 %tobool.not2, label %while.end, label %while.body.preheader

while.body.preheader:
  br label %while.body

while.body:
  %result.04 = phi i32 [ %inc, %while.body ], [ 0, %while.body.preheader ]
  %n.addr.03 = phi i64 [ %shr, %while.body ], [ %n, %while.body.preheader ]
  %shr = lshr i64 %n.addr.03, 1
  %inc = add i32 %result.04, 1
  %tobool.not = icmp ult i64 %n.addr.03, 4
  br i1 %tobool.not, label %while.end.loopexit, label %while.body

while.end.loopexit:
  %inc.lcssa = phi i32 [ %result.04, %while.body ]
  br label %while.end

while.end:
  %result.0.lcssa = phi i32 [ 0, %entry ], [ %inc.lcssa, %while.end.loopexit ]
  ret i32 %result.0.lcssa
}


; unsigned floor_log2_dec(unsigned long n) {
;   unsigned result = 0;
;   while (n >>= 1) result--;
;   return result;
; }

define i32 @floor_log2_dec(i64 noundef %n) {
; CHECK-LABEL: define i32 @floor_log2_dec(
; CHECK-SAME: i64 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TOBOOL_NOT2:%.*]] = icmp ult i64 [[N]], 2
; CHECK-NEXT:    br i1 [[TOBOOL_NOT2]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = call i64 @llvm.ctlz.i64(i64 [[N]], i1 true)
; CHECK-NEXT:    [[TMP1:%.*]] = sub i64 64, [[TMP0]]
; CHECK-NEXT:    [[TMP2:%.*]] = sub i64 [[TMP1]], 1
; CHECK-NEXT:    [[TMP3:%.*]] = trunc i64 [[TMP2]] to i32
; CHECK-NEXT:    [[TMP4:%.*]] = sub i32 0, [[TMP3]]
; CHECK-NEXT:    br label [[WHILE_BODY:%.*]]
; CHECK:       while.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i64 [ [[TMP2]], [[WHILE_BODY_PREHEADER]] ], [ [[TCDEC:%.*]], [[WHILE_BODY]] ]
; CHECK-NEXT:    [[RESULT_04:%.*]] = phi i32 [ [[INC:%.*]], [[WHILE_BODY]] ], [ 0, [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[N_ADDR_03:%.*]] = phi i64 [ [[SHR:%.*]], [[WHILE_BODY]] ], [ [[N]], [[WHILE_BODY_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = lshr i64 [[N_ADDR_03]], 1
; CHECK-NEXT:    [[INC]] = add i32 [[RESULT_04]], -1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i64 [[TCPHI]], 1
; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp eq i64 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[TOBOOL_NOT]], label [[WHILE_END_LOOPEXIT:%.*]], label [[WHILE_BODY]]
; CHECK:       while.end.loopexit:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[TMP4]], [[WHILE_BODY]] ]
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    [[RESULT_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC_LCSSA]], [[WHILE_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[RESULT_0_LCSSA]]
;
entry:
  %tobool.not2 = icmp ult i64 %n, 2
  br i1 %tobool.not2, label %while.end, label %while.body.preheader

while.body.preheader:
  br label %while.body

while.body:
  %result.04 = phi i32 [ %inc, %while.body ], [ 0, %while.body.preheader ]
  %n.addr.03 = phi i64 [ %shr, %while.body ], [ %n, %while.body.preheader ]
  %shr = lshr i64 %n.addr.03, 1
  %inc = add i32 %result.04, -1
  %tobool.not = icmp ult i64 %n.addr.03, 4
  br i1 %tobool.not, label %while.end.loopexit, label %while.body

while.end.loopexit:
  %inc.lcssa = phi i32 [ %inc, %while.body ]
  br label %while.end

while.end:
  %result.0.lcssa = phi i32 [ 0, %entry ], [ %inc.lcssa, %while.end.loopexit ]
  ret i32 %result.0.lcssa
}


; unsigned int_log2_rec(unsigned x) {
;   return x == 0 ? 0 : int_log2_rec(x >> 1) + 1;
; }

define i32 @int_log2_rec(i32 noundef %x) {
; CHECK-LABEL: define i32 @int_log2_rec(
; CHECK-SAME: i32 noundef [[X:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_END:%.*]], label [[COND_FALSE_PREHEADER:%.*]]
; CHECK:       cond.false.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = call i32 @llvm.ctlz.i32(i32 [[X]], i1 true)
; CHECK-NEXT:    [[TMP1:%.*]] = sub i32 32, [[TMP0]]
; CHECK-NEXT:    br label [[COND_FALSE:%.*]]
; CHECK:       cond.false:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP1]], [[COND_FALSE_PREHEADER]] ], [ [[TCDEC:%.*]], [[COND_FALSE]] ]
; CHECK-NEXT:    [[X_TR4:%.*]] = phi i32 [ [[SHR:%.*]], [[COND_FALSE]] ], [ [[X]], [[COND_FALSE_PREHEADER]] ]
; CHECK-NEXT:    [[ACCUMULATOR_TR3:%.*]] = phi i32 [ [[ADD:%.*]], [[COND_FALSE]] ], [ 0, [[COND_FALSE_PREHEADER]] ]
; CHECK-NEXT:    [[SHR]] = lshr i32 [[X_TR4]], 1
; CHECK-NEXT:    [[ADD]] = add i32 [[ACCUMULATOR_TR3]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[CMP]], label [[COND_END_LOOPEXIT:%.*]], label [[COND_FALSE]]
; CHECK:       cond.end.loopexit:
; CHECK-NEXT:    [[ADD_LCSSA:%.*]] = phi i32 [ [[TMP1]], [[COND_FALSE]] ]
; CHECK-NEXT:    br label [[COND_END]]
; CHECK:       cond.end:
; CHECK-NEXT:    [[ACCUMULATOR_TR_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[ADD_LCSSA]], [[COND_END_LOOPEXIT]] ]
; CHECK-NEXT:    ret i32 [[ACCUMULATOR_TR_LCSSA]]
;
entry:
  %cmp2 = icmp eq i32 %x, 0
  br i1 %cmp2, label %cond.end, label %cond.false.preheader

cond.false.preheader:                             ; preds = %entry
  br label %cond.false

cond.false:                                       ; preds = %cond.false.preheader, %cond.false
  %x.tr4 = phi i32 [ %shr, %cond.false ], [ %x, %cond.false.preheader ]
  %accumulator.tr3 = phi i32 [ %add, %cond.false ], [ 0, %cond.false.preheader ]
  %shr = lshr i32 %x.tr4, 1
  %add = add i32 %accumulator.tr3, 1
  %cmp = icmp ult i32 %x.tr4, 2
  br i1 %cmp, label %cond.end.loopexit, label %cond.false

cond.end.loopexit:                                ; preds = %cond.false
  %add.lcssa = phi i32 [ %add, %cond.false ]
  br label %cond.end

cond.end:                                         ; preds = %cond.end.loopexit, %entry
  %accumulator.tr.lcssa = phi i32 [ 0, %entry ], [ %add.lcssa, %cond.end.loopexit ]
  ret i32 %accumulator.tr.lcssa
}


; We can't easily transform this loop. It returns 1 for an input of both
; 0 and 1.
; int ctlz_do_while_use_inc(unsigned n)
; {
;   int i = 0;
;   do {
;     i++;
;     n >>= 1;
;   } while(n != 0);
;   return i;
; }

define i32 @ctlz_do_while_use_inc(i32 noundef %n) {
; CHECK-LABEL: define i32 @ctlz_do_while_use_inc(
; CHECK-SAME: i32 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[DO_BODY:%.*]]
; CHECK:       do.body:
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[N]], [[ENTRY:%.*]] ], [ [[SHR:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_0]], 1
; CHECK-NEXT:    [[SHR]] = lshr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[CMP_NOT:%.*]] = icmp ult i32 [[N_ADDR_0]], 2
; CHECK-NEXT:    br i1 [[CMP_NOT]], label [[DO_END:%.*]], label [[DO_BODY]]
; CHECK:       do.end:
; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ [[INC]], [[DO_BODY]] ]
; CHECK-NEXT:    ret i32 [[INC_LCSSA]]
;
entry:
  br label %do.body

do.body:                                          ; preds = %do.body, %entry
  %n.addr.0 = phi i32 [ %n, %entry ], [ %shr, %do.body ]
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %do.body ]
  %inc = add nuw nsw i32 %i.0, 1
  %shr = lshr i32 %n.addr.0, 1
  %cmp.not = icmp ult i32 %n.addr.0, 2
  br i1 %cmp.not, label %do.end, label %do.body

do.end:                                           ; preds = %do.body
  %inc.lcssa = phi i32 [ %inc, %do.body ]
  ret i32 %inc.lcssa
}


; Recognize CTLZ builtin pattern.
; Here it will replace the loop -
; assume builtin is always profitable.
;
; int ctlz_do_while_use_phi(unsigned n)
; {
;   int phi;
;   int inc = 0;
;   do {
;     phi = inc;
;     inc++;
;     n >>= 1;
;   } while(n != 0);
;   return phi;
; }

define i32 @ctlz_do_while_use_phi(i32 noundef %n) {
; CHECK-LABEL: define i32 @ctlz_do_while_use_phi(
; CHECK-SAME: i32 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TMP0:%.*]] = lshr i32 [[N]], 1
; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.ctlz.i32(i32 [[TMP0]], i1 false)
; CHECK-NEXT:    [[TMP2:%.*]] = sub i32 32, [[TMP1]]
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    br label [[DO_BODY:%.*]]
; CHECK:       do.body:
; CHECK-NEXT:    [[TCPHI:%.*]] = phi i32 [ [[TMP3]], [[ENTRY:%.*]] ], [ [[TCDEC:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i32 [ [[N]], [[ENTRY]] ], [ [[SHR:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[INC_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC1:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[INC1]] = add nuw nsw i32 [[INC_0]], 1
; CHECK-NEXT:    [[SHR]] = lshr i32 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[TCDEC]] = sub nsw i32 [[TCPHI]], 1
; CHECK-NEXT:    [[CMP_NOT:%.*]] = icmp eq i32 [[TCDEC]], 0
; CHECK-NEXT:    br i1 [[CMP_NOT]], label [[DO_END:%.*]], label [[DO_BODY]]
; CHECK:       do.end:
; CHECK-NEXT:    [[INC_0_LCSSA:%.*]] = phi i32 [ [[TMP2]], [[DO_BODY]] ]
; CHECK-NEXT:    ret i32 [[INC_0_LCSSA]]
;
entry:
  br label %do.body

do.body:                                          ; preds = %do.body, %entry
  %n.addr.0 = phi i32 [ %n, %entry ], [ %shr, %do.body ]
  %inc.0 = phi i32 [ 0, %entry ], [ %inc1, %do.body ]
  %inc1 = add nuw nsw i32 %inc.0, 1
  %shr = lshr i32 %n.addr.0, 1
  %cmp.not = icmp ult i32 %n.addr.0, 2
  br i1 %cmp.not, label %do.end, label %do.body

do.end:                                           ; preds = %do.body
  ret i32 %inc.0
}

; Check that we correctly bail on analysis when the ult comparison is with a
; constant that exceeds the (unsigned) range of a 64-bit integer, as we currently
; only handle loopback condition ult 2 or 4.

define i128 @large_constant(i128 noundef %n) {
; CHECK-LABEL: define i128 @large_constant(
; CHECK-SAME: i128 noundef [[N:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[DO_BODY:%.*]]
; CHECK:       do.body:
; CHECK-NEXT:    [[N_ADDR_0:%.*]] = phi i128 [ [[N]], [[ENTRY:%.*]] ], [ [[SHR:%.*]], [[DO_BODY]] ]
; CHECK-NEXT:    [[SHR]] = lshr i128 [[N_ADDR_0]], 1
; CHECK-NEXT:    [[CMP_NOT:%.*]] = icmp ult i128 [[N_ADDR_0]], 18446744073709551616
; CHECK-NEXT:    br i1 [[CMP_NOT]], label [[DO_END:%.*]], label [[DO_BODY]]
; CHECK:       do.end:
; CHECK-NEXT:    [[SHR_LCSSA:%.*]] = phi i128 [ [[SHR]], [[DO_BODY]] ]
; CHECK-NEXT:    ret i128 [[SHR_LCSSA]]
;
entry:
  br label %do.body

do.body:                                          ; preds = %do.body, %entry
  %n.addr.0 = phi i128 [ %n, %entry ], [ %shr, %do.body ]
  %shr = lshr i128 %n.addr.0, 1
  %cmp.not = icmp ult i128 %n.addr.0, 18446744073709551616
  br i1 %cmp.not, label %do.end, label %do.body

do.end:                                           ; preds = %do.body
  ret i128 %shr
}


declare i32 @llvm.abs.i32(i32, i1)
declare i16 @llvm.abs.i16(i16, i1)