zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/lib/libssl/openssl-1.1.1o/crypto/modes/asm/ghash-armv4.pl b/ap/lib/libssl/openssl-1.1.1o/crypto/modes/asm/ghash-armv4.pl
new file mode 100644
index 0000000..d84ac6f
--- /dev/null
+++ b/ap/lib/libssl/openssl-1.1.1o/crypto/modes/asm/ghash-armv4.pl
@@ -0,0 +1,551 @@
+#! /usr/bin/env perl
+# Copyright 2010-2020 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the OpenSSL license (the "License"). You may not use
+# this file except in compliance with the License. You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+#
+# ====================================================================
+# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
+# project. The module is, however, dual licensed under OpenSSL and
+# CRYPTOGAMS licenses depending on where you obtain it. For further
+# details see http://www.openssl.org/~appro/cryptogams/.
+# ====================================================================
+#
+# April 2010
+#
+# The module implements "4-bit" GCM GHASH function and underlying
+# single multiplication operation in GF(2^128). "4-bit" means that it
+# uses 256 bytes per-key table [+32 bytes shared table]. There is no
+# experimental performance data available yet. The only approximation
+# that can be made at this point is based on code size. Inner loop is
+# 32 instructions long and on single-issue core should execute in <40
+# cycles. Having verified that gcc 3.4 didn't unroll corresponding
+# loop, this assembler loop body was found to be ~3x smaller than
+# compiler-generated one...
+#
+# July 2010
+#
+# Rescheduling for dual-issue pipeline resulted in 8.5% improvement on
+# Cortex A8 core and ~25 cycles per processed byte (which was observed
+# to be ~3 times faster than gcc-generated code:-)
+#
+# February 2011
+#
+# Profiler-assisted and platform-specific optimization resulted in 7%
+# improvement on Cortex A8 core and ~23.5 cycles per byte.
+#
+# March 2011
+#
+# Add NEON implementation featuring polynomial multiplication, i.e. no
+# lookup tables involved. On Cortex A8 it was measured to process one
+# byte in 15 cycles or 55% faster than integer-only code.
+#
+# April 2014
+#
+# Switch to multiplication algorithm suggested in paper referred
+# below and combine it with reduction algorithm from x86 module.
+# Performance improvement over previous version varies from 65% on
+# Snapdragon S4 to 110% on Cortex A9. In absolute terms Cortex A8
+# processes one byte in 8.45 cycles, A9 - in 10.2, A15 - in 7.63,
+# Snapdragon S4 - in 9.33.
+#
+# Câmara, D.; Gouvêa, C. P. L.; López, J. & Dahab, R.: Fast Software
+# Polynomial Multiplication on ARM Processors using the NEON Engine.
+#
+# http://conradoplg.cryptoland.net/files/2010/12/mocrysen13.pdf
+
+# ====================================================================
+# Note about "528B" variant. In ARM case it makes lesser sense to
+# implement it for following reasons:
+#
+# - performance improvement won't be anywhere near 50%, because 128-
+# bit shift operation is neatly fused with 128-bit xor here, and
+# "538B" variant would eliminate only 4-5 instructions out of 32
+# in the inner loop (meaning that estimated improvement is ~15%);
+# - ARM-based systems are often embedded ones and extra memory
+# consumption might be unappreciated (for so little improvement);
+#
+# Byte order [in]dependence. =========================================
+#
+# Caller is expected to maintain specific *dword* order in Htable,
+# namely with *least* significant dword of 128-bit value at *lower*
+# address. This differs completely from C code and has everything to
+# do with ldm instruction and order in which dwords are "consumed" by
+# algorithm. *Byte* order within these dwords in turn is whatever
+# *native* byte order on current platform. See gcm128.c for working
+# example...
+
+$flavour = shift;
+if ($flavour=~/\w[\w\-]*\.\w+$/) { $output=$flavour; undef $flavour; }
+else { while (($output=shift) && ($output!~/\w[\w\-]*\.\w+$/)) {} }
+
+if ($flavour && $flavour ne "void") {
+ $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
+ ( $xlate="${dir}arm-xlate.pl" and -f $xlate ) or
+ ( $xlate="${dir}../../perlasm/arm-xlate.pl" and -f $xlate) or
+ die "can't locate arm-xlate.pl";
+
+ open STDOUT,"| \"$^X\" $xlate $flavour $output";
+} else {
+ open STDOUT,">$output";
+}
+
+$Xi="r0"; # argument block
+$Htbl="r1";
+$inp="r2";
+$len="r3";
+
+$Zll="r4"; # variables
+$Zlh="r5";
+$Zhl="r6";
+$Zhh="r7";
+$Tll="r8";
+$Tlh="r9";
+$Thl="r10";
+$Thh="r11";
+$nlo="r12";
+################# r13 is stack pointer
+$nhi="r14";
+################# r15 is program counter
+
+$rem_4bit=$inp; # used in gcm_gmult_4bit
+$cnt=$len;
+
+sub Zsmash() {
+ my $i=12;
+ my @args=@_;
+ for ($Zll,$Zlh,$Zhl,$Zhh) {
+ $code.=<<___;
+#if __ARM_ARCH__>=7 && defined(__ARMEL__)
+ rev $_,$_
+ str $_,[$Xi,#$i]
+#elif defined(__ARMEB__)
+ str $_,[$Xi,#$i]
+#else
+ mov $Tlh,$_,lsr#8
+ strb $_,[$Xi,#$i+3]
+ mov $Thl,$_,lsr#16
+ strb $Tlh,[$Xi,#$i+2]
+ mov $Thh,$_,lsr#24
+ strb $Thl,[$Xi,#$i+1]
+ strb $Thh,[$Xi,#$i]
+#endif
+___
+ $code.="\t".shift(@args)."\n";
+ $i-=4;
+ }
+}
+
+$code=<<___;
+#include "arm_arch.h"
+
+.text
+#if defined(__thumb2__) || defined(__clang__)
+.syntax unified
+#define ldrplb ldrbpl
+#define ldrneb ldrbne
+#endif
+#if defined(__thumb2__)
+.thumb
+#else
+.code 32
+#endif
+
+.type rem_4bit,%object
+.align 5
+rem_4bit:
+.short 0x0000,0x1C20,0x3840,0x2460
+.short 0x7080,0x6CA0,0x48C0,0x54E0
+.short 0xE100,0xFD20,0xD940,0xC560
+.short 0x9180,0x8DA0,0xA9C0,0xB5E0
+.size rem_4bit,.-rem_4bit
+
+.type rem_4bit_get,%function
+rem_4bit_get:
+#if defined(__thumb2__)
+ adr $rem_4bit,rem_4bit
+#else
+ sub $rem_4bit,pc,#8+32 @ &rem_4bit
+#endif
+ b .Lrem_4bit_got
+ nop
+ nop
+.size rem_4bit_get,.-rem_4bit_get
+
+.global gcm_ghash_4bit
+.type gcm_ghash_4bit,%function
+.align 4
+gcm_ghash_4bit:
+#if defined(__thumb2__)
+ adr r12,rem_4bit
+#else
+ sub r12,pc,#8+48 @ &rem_4bit
+#endif
+ add $len,$inp,$len @ $len to point at the end
+ stmdb sp!,{r3-r11,lr} @ save $len/end too
+
+ ldmia r12,{r4-r11} @ copy rem_4bit ...
+ stmdb sp!,{r4-r11} @ ... to stack
+
+ ldrb $nlo,[$inp,#15]
+ ldrb $nhi,[$Xi,#15]
+.Louter:
+ eor $nlo,$nlo,$nhi
+ and $nhi,$nlo,#0xf0
+ and $nlo,$nlo,#0x0f
+ mov $cnt,#14
+
+ add $Zhh,$Htbl,$nlo,lsl#4
+ ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
+ add $Thh,$Htbl,$nhi
+ ldrb $nlo,[$inp,#14]
+
+ and $nhi,$Zll,#0xf @ rem
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
+ add $nhi,$nhi,$nhi
+ eor $Zll,$Tll,$Zll,lsr#4
+ ldrh $Tll,[sp,$nhi] @ rem_4bit[rem]
+ eor $Zll,$Zll,$Zlh,lsl#28
+ ldrb $nhi,[$Xi,#14]
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ eor $Zhl,$Thl,$Zhl,lsr#4
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+ eor $Zhh,$Thh,$Zhh,lsr#4
+ eor $nlo,$nlo,$nhi
+ and $nhi,$nlo,#0xf0
+ and $nlo,$nlo,#0x0f
+ eor $Zhh,$Zhh,$Tll,lsl#16
+
+.Linner:
+ add $Thh,$Htbl,$nlo,lsl#4
+ and $nlo,$Zll,#0xf @ rem
+ subs $cnt,$cnt,#1
+ add $nlo,$nlo,$nlo
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
+ eor $Zll,$Tll,$Zll,lsr#4
+ eor $Zll,$Zll,$Zlh,lsl#28
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ ldrh $Tll,[sp,$nlo] @ rem_4bit[rem]
+ eor $Zhl,$Thl,$Zhl,lsr#4
+#ifdef __thumb2__
+ it pl
+#endif
+ ldrplb $nlo,[$inp,$cnt]
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+ eor $Zhh,$Thh,$Zhh,lsr#4
+
+ add $Thh,$Htbl,$nhi
+ and $nhi,$Zll,#0xf @ rem
+ eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
+ add $nhi,$nhi,$nhi
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
+ eor $Zll,$Tll,$Zll,lsr#4
+#ifdef __thumb2__
+ it pl
+#endif
+ ldrplb $Tll,[$Xi,$cnt]
+ eor $Zll,$Zll,$Zlh,lsl#28
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ ldrh $Tlh,[sp,$nhi]
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ eor $Zhl,$Thl,$Zhl,lsr#4
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+#ifdef __thumb2__
+ it pl
+#endif
+ eorpl $nlo,$nlo,$Tll
+ eor $Zhh,$Thh,$Zhh,lsr#4
+#ifdef __thumb2__
+ itt pl
+#endif
+ andpl $nhi,$nlo,#0xf0
+ andpl $nlo,$nlo,#0x0f
+ eor $Zhh,$Zhh,$Tlh,lsl#16 @ ^= rem_4bit[rem]
+ bpl .Linner
+
+ ldr $len,[sp,#32] @ re-load $len/end
+ add $inp,$inp,#16
+ mov $nhi,$Zll
+___
+ &Zsmash("cmp\t$inp,$len","\n".
+ "#ifdef __thumb2__\n".
+ " it ne\n".
+ "#endif\n".
+ " ldrneb $nlo,[$inp,#15]");
+$code.=<<___;
+ bne .Louter
+
+ add sp,sp,#36
+#if __ARM_ARCH__>=5
+ ldmia sp!,{r4-r11,pc}
+#else
+ ldmia sp!,{r4-r11,lr}
+ tst lr,#1
+ moveq pc,lr @ be binary compatible with V4, yet
+ bx lr @ interoperable with Thumb ISA:-)
+#endif
+.size gcm_ghash_4bit,.-gcm_ghash_4bit
+
+.global gcm_gmult_4bit
+.type gcm_gmult_4bit,%function
+gcm_gmult_4bit:
+ stmdb sp!,{r4-r11,lr}
+ ldrb $nlo,[$Xi,#15]
+ b rem_4bit_get
+.Lrem_4bit_got:
+ and $nhi,$nlo,#0xf0
+ and $nlo,$nlo,#0x0f
+ mov $cnt,#14
+
+ add $Zhh,$Htbl,$nlo,lsl#4
+ ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
+ ldrb $nlo,[$Xi,#14]
+
+ add $Thh,$Htbl,$nhi
+ and $nhi,$Zll,#0xf @ rem
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
+ add $nhi,$nhi,$nhi
+ eor $Zll,$Tll,$Zll,lsr#4
+ ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
+ eor $Zll,$Zll,$Zlh,lsl#28
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ eor $Zhl,$Thl,$Zhl,lsr#4
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+ eor $Zhh,$Thh,$Zhh,lsr#4
+ and $nhi,$nlo,#0xf0
+ eor $Zhh,$Zhh,$Tll,lsl#16
+ and $nlo,$nlo,#0x0f
+
+.Loop:
+ add $Thh,$Htbl,$nlo,lsl#4
+ and $nlo,$Zll,#0xf @ rem
+ subs $cnt,$cnt,#1
+ add $nlo,$nlo,$nlo
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
+ eor $Zll,$Tll,$Zll,lsr#4
+ eor $Zll,$Zll,$Zlh,lsl#28
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ ldrh $Tll,[$rem_4bit,$nlo] @ rem_4bit[rem]
+ eor $Zhl,$Thl,$Zhl,lsr#4
+#ifdef __thumb2__
+ it pl
+#endif
+ ldrplb $nlo,[$Xi,$cnt]
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+ eor $Zhh,$Thh,$Zhh,lsr#4
+
+ add $Thh,$Htbl,$nhi
+ and $nhi,$Zll,#0xf @ rem
+ eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
+ add $nhi,$nhi,$nhi
+ ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
+ eor $Zll,$Tll,$Zll,lsr#4
+ eor $Zll,$Zll,$Zlh,lsl#28
+ eor $Zlh,$Tlh,$Zlh,lsr#4
+ ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
+ eor $Zlh,$Zlh,$Zhl,lsl#28
+ eor $Zhl,$Thl,$Zhl,lsr#4
+ eor $Zhl,$Zhl,$Zhh,lsl#28
+ eor $Zhh,$Thh,$Zhh,lsr#4
+#ifdef __thumb2__
+ itt pl
+#endif
+ andpl $nhi,$nlo,#0xf0
+ andpl $nlo,$nlo,#0x0f
+ eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
+ bpl .Loop
+___
+ &Zsmash();
+$code.=<<___;
+#if __ARM_ARCH__>=5
+ ldmia sp!,{r4-r11,pc}
+#else
+ ldmia sp!,{r4-r11,lr}
+ tst lr,#1
+ moveq pc,lr @ be binary compatible with V4, yet
+ bx lr @ interoperable with Thumb ISA:-)
+#endif
+.size gcm_gmult_4bit,.-gcm_gmult_4bit
+___
+{
+my ($Xl,$Xm,$Xh,$IN)=map("q$_",(0..3));
+my ($t0,$t1,$t2,$t3)=map("q$_",(8..12));
+my ($Hlo,$Hhi,$Hhl,$k48,$k32,$k16)=map("d$_",(26..31));
+
+sub clmul64x64 {
+my ($r,$a,$b)=@_;
+$code.=<<___;
+ vext.8 $t0#lo, $a, $a, #1 @ A1
+ vmull.p8 $t0, $t0#lo, $b @ F = A1*B
+ vext.8 $r#lo, $b, $b, #1 @ B1
+ vmull.p8 $r, $a, $r#lo @ E = A*B1
+ vext.8 $t1#lo, $a, $a, #2 @ A2
+ vmull.p8 $t1, $t1#lo, $b @ H = A2*B
+ vext.8 $t3#lo, $b, $b, #2 @ B2
+ vmull.p8 $t3, $a, $t3#lo @ G = A*B2
+ vext.8 $t2#lo, $a, $a, #3 @ A3
+ veor $t0, $t0, $r @ L = E + F
+ vmull.p8 $t2, $t2#lo, $b @ J = A3*B
+ vext.8 $r#lo, $b, $b, #3 @ B3
+ veor $t1, $t1, $t3 @ M = G + H
+ vmull.p8 $r, $a, $r#lo @ I = A*B3
+ veor $t0#lo, $t0#lo, $t0#hi @ t0 = (L) (P0 + P1) << 8
+ vand $t0#hi, $t0#hi, $k48
+ vext.8 $t3#lo, $b, $b, #4 @ B4
+ veor $t1#lo, $t1#lo, $t1#hi @ t1 = (M) (P2 + P3) << 16
+ vand $t1#hi, $t1#hi, $k32
+ vmull.p8 $t3, $a, $t3#lo @ K = A*B4
+ veor $t2, $t2, $r @ N = I + J
+ veor $t0#lo, $t0#lo, $t0#hi
+ veor $t1#lo, $t1#lo, $t1#hi
+ veor $t2#lo, $t2#lo, $t2#hi @ t2 = (N) (P4 + P5) << 24
+ vand $t2#hi, $t2#hi, $k16
+ vext.8 $t0, $t0, $t0, #15
+ veor $t3#lo, $t3#lo, $t3#hi @ t3 = (K) (P6 + P7) << 32
+ vmov.i64 $t3#hi, #0
+ vext.8 $t1, $t1, $t1, #14
+ veor $t2#lo, $t2#lo, $t2#hi
+ vmull.p8 $r, $a, $b @ D = A*B
+ vext.8 $t3, $t3, $t3, #12
+ vext.8 $t2, $t2, $t2, #13
+ veor $t0, $t0, $t1
+ veor $t2, $t2, $t3
+ veor $r, $r, $t0
+ veor $r, $r, $t2
+___
+}
+
+$code.=<<___;
+#if __ARM_MAX_ARCH__>=7
+.arch armv7-a
+.fpu neon
+
+.global gcm_init_neon
+.type gcm_init_neon,%function
+.align 4
+gcm_init_neon:
+ vld1.64 $IN#hi,[r1]! @ load H
+ vmov.i8 $t0,#0xe1
+ vld1.64 $IN#lo,[r1]
+ vshl.i64 $t0#hi,#57
+ vshr.u64 $t0#lo,#63 @ t0=0xc2....01
+ vdup.8 $t1,$IN#hi[7]
+ vshr.u64 $Hlo,$IN#lo,#63
+ vshr.s8 $t1,#7 @ broadcast carry bit
+ vshl.i64 $IN,$IN,#1
+ vand $t0,$t0,$t1
+ vorr $IN#hi,$Hlo @ H<<<=1
+ veor $IN,$IN,$t0 @ twisted H
+ vstmia r0,{$IN}
+
+ ret @ bx lr
+.size gcm_init_neon,.-gcm_init_neon
+
+.global gcm_gmult_neon
+.type gcm_gmult_neon,%function
+.align 4
+gcm_gmult_neon:
+ vld1.64 $IN#hi,[$Xi]! @ load Xi
+ vld1.64 $IN#lo,[$Xi]!
+ vmov.i64 $k48,#0x0000ffffffffffff
+ vldmia $Htbl,{$Hlo-$Hhi} @ load twisted H
+ vmov.i64 $k32,#0x00000000ffffffff
+#ifdef __ARMEL__
+ vrev64.8 $IN,$IN
+#endif
+ vmov.i64 $k16,#0x000000000000ffff
+ veor $Hhl,$Hlo,$Hhi @ Karatsuba pre-processing
+ mov $len,#16
+ b .Lgmult_neon
+.size gcm_gmult_neon,.-gcm_gmult_neon
+
+.global gcm_ghash_neon
+.type gcm_ghash_neon,%function
+.align 4
+gcm_ghash_neon:
+ vld1.64 $Xl#hi,[$Xi]! @ load Xi
+ vld1.64 $Xl#lo,[$Xi]!
+ vmov.i64 $k48,#0x0000ffffffffffff
+ vldmia $Htbl,{$Hlo-$Hhi} @ load twisted H
+ vmov.i64 $k32,#0x00000000ffffffff
+#ifdef __ARMEL__
+ vrev64.8 $Xl,$Xl
+#endif
+ vmov.i64 $k16,#0x000000000000ffff
+ veor $Hhl,$Hlo,$Hhi @ Karatsuba pre-processing
+
+.Loop_neon:
+ vld1.64 $IN#hi,[$inp]! @ load inp
+ vld1.64 $IN#lo,[$inp]!
+#ifdef __ARMEL__
+ vrev64.8 $IN,$IN
+#endif
+ veor $IN,$Xl @ inp^=Xi
+.Lgmult_neon:
+___
+ &clmul64x64 ($Xl,$Hlo,"$IN#lo"); # H.lo·Xi.lo
+$code.=<<___;
+ veor $IN#lo,$IN#lo,$IN#hi @ Karatsuba pre-processing
+___
+ &clmul64x64 ($Xm,$Hhl,"$IN#lo"); # (H.lo+H.hi)·(Xi.lo+Xi.hi)
+ &clmul64x64 ($Xh,$Hhi,"$IN#hi"); # H.hi·Xi.hi
+$code.=<<___;
+ veor $Xm,$Xm,$Xl @ Karatsuba post-processing
+ veor $Xm,$Xm,$Xh
+ veor $Xl#hi,$Xl#hi,$Xm#lo
+ veor $Xh#lo,$Xh#lo,$Xm#hi @ Xh|Xl - 256-bit result
+
+ @ equivalent of reduction_avx from ghash-x86_64.pl
+ vshl.i64 $t1,$Xl,#57 @ 1st phase
+ vshl.i64 $t2,$Xl,#62
+ veor $t2,$t2,$t1 @
+ vshl.i64 $t1,$Xl,#63
+ veor $t2, $t2, $t1 @
+ veor $Xl#hi,$Xl#hi,$t2#lo @
+ veor $Xh#lo,$Xh#lo,$t2#hi
+
+ vshr.u64 $t2,$Xl,#1 @ 2nd phase
+ veor $Xh,$Xh,$Xl
+ veor $Xl,$Xl,$t2 @
+ vshr.u64 $t2,$t2,#6
+ vshr.u64 $Xl,$Xl,#1 @
+ veor $Xl,$Xl,$Xh @
+ veor $Xl,$Xl,$t2 @
+
+ subs $len,#16
+ bne .Loop_neon
+
+#ifdef __ARMEL__
+ vrev64.8 $Xl,$Xl
+#endif
+ sub $Xi,#16
+ vst1.64 $Xl#hi,[$Xi]! @ write out Xi
+ vst1.64 $Xl#lo,[$Xi]
+
+ ret @ bx lr
+.size gcm_ghash_neon,.-gcm_ghash_neon
+#endif
+___
+}
+$code.=<<___;
+.asciz "GHASH for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
+.align 2
+___
+
+foreach (split("\n",$code)) {
+ s/\`([^\`]*)\`/eval $1/geo;
+
+ s/\bq([0-9]+)#(lo|hi)/sprintf "d%d",2*$1+($2 eq "hi")/geo or
+ s/\bret\b/bx lr/go or
+ s/\bbx\s+lr\b/.word\t0xe12fff1e/go; # make it possible to compile with -march=armv4
+
+ print $_,"\n";
+}
+close STDOUT or die "error closing STDOUT: $!"; # enforce flush