lib/crypto/mips/poly1305-mips.pl

Source file repositories/reference/linux-study-clean/lib/crypto/mips/poly1305-mips.pl

File Facts

System
Linux kernel
Corpus path
lib/crypto/mips/poly1305-mips.pl
Extension
.pl
Size
24359 bytes
Lines
1270
Domain
Kernel Services
Bucket
lib
Inferred role
Kernel Services: lib
Status
atlas-only

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

#!/usr/bin/env perl
# SPDX-License-Identifier: GPL-1.0+ OR BSD-3-Clause
#
# ====================================================================
# Written by Andy Polyakov, @dot-asm, originally for the OpenSSL
# project.
# ====================================================================

# Poly1305 hash for MIPS.
#
# May 2016
#
# Numbers are cycles per processed byte with poly1305_blocks alone.
#
#		IALU/gcc
# R1x000	~5.5/+130%	(big-endian)
# Octeon II	2.50/+70%	(little-endian)
#
# March 2019
#
# Add 32-bit code path.
#
# October 2019
#
# Modulo-scheduling reduction allows to omit dependency chain at the
# end of inner loop and improve performance. Also optimize MIPS32R2
# code path for MIPS 1004K core. Per René von Dorst's suggestions.
#
#		IALU/gcc
# R1x000	~9.8/?		(big-endian)
# Octeon II	3.65/+140%	(little-endian)
# MT7621/1004K	4.75/?		(little-endian)
#
######################################################################
# There is a number of MIPS ABI in use, O32 and N32/64 are most
# widely used. Then there is a new contender: NUBI. It appears that if
# one picks the latter, it's possible to arrange code in ABI neutral
# manner. Therefore let's stick to NUBI register layout:
#
($zero,$at,$t0,$t1,$t2)=map("\$$_",(0..2,24,25));
($a0,$a1,$a2,$a3,$a4,$a5,$a6,$a7)=map("\$$_",(4..11));
($s0,$s1,$s2,$s3,$s4,$s5,$s6,$s7,$s8,$s9,$s10,$s11)=map("\$$_",(12..23));
($gp,$tp,$sp,$fp,$ra)=map("\$$_",(3,28..31));
#
# The return value is placed in $a0. Following coding rules facilitate
# interoperability:
#
# - never ever touch $tp, "thread pointer", former $gp [o32 can be
#   excluded from the rule, because it's specified volatile];
# - copy return value to $t0, former $v0 [or to $a0 if you're adapting
#   old code];
# - on O32 populate $a4-$a7 with 'lw $aN,4*N($sp)' if necessary;
#
# For reference here is register layout for N32/64 MIPS ABIs:
#
# ($zero,$at,$v0,$v1)=map("\$$_",(0..3));
# ($a0,$a1,$a2,$a3,$a4,$a5,$a6,$a7)=map("\$$_",(4..11));
# ($t0,$t1,$t2,$t3,$t8,$t9)=map("\$$_",(12..15,24,25));
# ($s0,$s1,$s2,$s3,$s4,$s5,$s6,$s7)=map("\$$_",(16..23));
# ($gp,$sp,$fp,$ra)=map("\$$_",(28..31));
#
# <appro@openssl.org>
#
######################################################################

$flavour = shift || "64"; # supported flavours are o32,n32,64,nubi32,nubi64

$v0 = ($flavour =~ /nubi/i) ? $a0 : $t0;

if ($flavour =~ /64|n32/i) {{{

Annotation

Implementation Notes