Initial import

libc/nexgen32e/ktolower.S

@@ -0,0 +1,61 @@
+/*-*- mode:asm; indent-tabs-mode:t; tab-width:8; coding:utf-8               -*-│
+│vi: set et ft=asm ts=8 sw=8 fenc=utf-8                                     :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ This program is free software; you can redistribute it and/or modify         │
+│ it under the terms of the GNU General Public License as published by         │
+│ the Free Software Foundation; version 2 of the License.                      │
+│                                                                              │
+│ This program is distributed in the hope that it will be useful, but          │
+│ WITHOUT ANY WARRANTY; without even the implied warranty of                   │
+│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU             │
+│ General Public License for more details.                                     │
+│                                                                              │
+│ You should have received a copy of the GNU General Public License            │
+│ along with this program; if not, write to the Free Software                  │
+│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
+│ 02110-1301 USA                                                               │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/macros.h"
+
+/	ASCII uppercase → lowercase translation tables.
+/
+/		char kToLower[256];
+/		char16_t kToLower16[256];
+/
+/	@note	kToLower16 saves 128kb; CMOVcc can't even 8-bit
+	.initbss 300,_init_kToLower
+kToLower:
+	.rept	256
+	.byte	0
+	.endr
+	.endobj	kToLower,globl,hidden
+kToLower16:
+	.rept	256
+	.short	0
+	.endr
+	.endobj	kToLower16,globl,hidden
+	.previous
+
+	.init.start 300,_init_kToLower
+	push	%rdi
+	call	imapxlatab
+	xchg	%rsi,(%rsp)
+	xor	%ecx,%ecx
+0:	inc	%ecx
+	addb	$0x20,'A-1(%rsi,%rcx)
+	cmp	$'Z-'A,%ecx
+	jne	0b
+	xor	%eax,%eax
+	mov	$256,%ecx
+0:	lodsb
+	stosw
+	loop	0b
+	pop	%rsi
+	.init.end 300,_init_kToLower
+
+	.type	gperf_downcase,@object
+	.globl	gperf_downcase
+	gperf_downcase = kToLower
+	.yoink	__FILE__