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rust / rust-lang / llvm-project / e8a2ffcf322f45b8dce82c65ab27a3e2430a6b51 / . / llvm / test / Transforms / LoopIdiom / AArch64 / ctlz.ll
blob: 5a182745399beedcc9e3134f1602b7e7cee93104 [file] [log] [blame]
; 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 nocapture [[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)