ref: 13ca2581f9f18d441ce911e42c2bd93e387cee4d
dir: /code/unix/linux_common.c/
/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
This file is part of Quake III Arena source code.
Quake III Arena source code 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; either version 2 of the License,
or (at your option) any later version.
Quake III Arena source code 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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
===========================================================================
*/
/**
* GAS syntax equivalents of the MSVC asm memory calls in common.c
*
* The following changes have been made to the asm:
* 1. Registers are loaded by the inline asm arguments when possible
* 2. Labels have been changed to local label format (0,1,etc.) to allow inlining
*
* HISTORY:
* AH - Created on 08 Dec 2000
*/
#include <unistd.h> // AH - for size_t
#include <string.h>
// bk001207 - we need something under Linux, too. Mac?
#if 1 // defined(C_ONLY) // bk010102 - dedicated?
void Com_Memcpy (void* dest, const void* src, const size_t count) {
memcpy(dest, src, count);
}
void Com_Memset (void* dest, const int val, const size_t count) {
memset(dest, val, count);
}
#else
typedef enum {
PRE_READ, // prefetch assuming that buffer is used for reading only
PRE_WRITE, // prefetch assuming that buffer is used for writing only
PRE_READ_WRITE // prefetch assuming that buffer is used for both reading and writing
} e_prefetch;
void Com_Prefetch (const void *s, const unsigned int bytes, e_prefetch type);
void _copyDWord (unsigned int* dest, const unsigned int constant, const unsigned int count) {
// MMX version not used on standard Pentium MMX
// because the dword version is faster (with
// proper destination prefetching)
__asm__ __volatile__ (" \
//mov eax,constant // eax = val \
//mov edx,dest // dest \
//mov ecx,count \
movd %%eax, %%mm0 \
punpckldq %%mm0, %%mm0 \
\
// ensure that destination is qword aligned \
\
testl $7, %%edx // qword padding?\
jz 0f \
movl %%eax, (%%edx) \
decl %%ecx \
addl $4, %%edx \
\
0: movl %%ecx, %%ebx \
andl $0xfffffff0, %%ecx \
jz 2f \
jmp 1f \
.align 16 \
\
// funny ordering here to avoid commands \
// that cross 32-byte boundaries (the \
// [edx+0] version has a special 3-byte opcode... \
1: movq %%mm0, 8(%%edx) \
movq %%mm0, 16(%%edx) \
movq %%mm0, 24(%%edx) \
movq %%mm0, 32(%%edx) \
movq %%mm0, 40(%%edx) \
movq %%mm0, 48(%%edx) \
movq %%mm0, 56(%%edx) \
movq %%mm0, (%%edx)\
addl $64, %%edx \
subl $16, %%ecx \
jnz 1b \
2: \
movl %%ebx, %%ecx // ebx = cnt \
andl $0xfffffff0, %%ecx // ecx = cnt&~15 \
subl %%ecx, %%ebx \
jz 6f \
cmpl $8, %%ebx \
jl 3f \
\
movq %%mm0, (%%edx) \
movq %%mm0, 8(%%edx) \
movq %%mm0, 16(%%edx) \
movq %%mm0, 24(%%edx) \
addl $32, %%edx \
subl $8, %%ebx \
jz 6f \
\
3: cmpl $4, %%ebx \
jl 4f \
\
movq %%mm0, (%%edx) \
movq %%mm0, 8(%%edx) \
addl $16, %%edx \
subl $4, %%ebx \
\
4: cmpl $2, %%ebx \
jl 5f \
movq %%mm0, (%%edx) \
addl $8, %%edx \
subl $2, %%ebx \
\
5: cmpl $1, %%ebx \
jl 6f \
movl %%eax, (%%edx) \
6: \
emms \
"
: : "a" (constant), "c" (count), "d" (dest)
: "%ebx", "%edi", "%esi", "cc", "memory");
}
// optimized memory copy routine that handles all alignment
// cases and block sizes efficiently
void Com_Memcpy (void* dest, const void* src, const size_t count) {
Com_Prefetch (src, count, PRE_READ);
__asm__ __volatile__ (" \
pushl %%edi \
pushl %%esi \
//mov ecx,count \
cmpl $0, %%ecx // count = 0 check (just to be on the safe side) \
je 6f \
//mov edx,dest \
movl %0, %%ebx \
cmpl $32, %%ecx // padding only? \
jl 1f \
\
movl %%ecx, %%edi \
andl $0xfffffe00, %%edi // edi = count&~31 \
subl $32, %%edi \
\
.align 16 \
0: \
movl (%%ebx, %%edi, 1), %%eax \
movl 4(%%ebx, %%edi, 1), %%esi \
movl %%eax, (%%edx, %%edi, 1) \
movl %%esi, 4(%%edx, %%edi, 1) \
movl 8(%%ebx, %%edi, 1), %%eax \
movl 12(%%ebx, %%edi, 1), %%esi \
movl %%eax, 8(%%edx, %%edi, 1) \
movl %%esi, 12(%%edx, %%edi, 1) \
movl 16(%%ebx, %%edi, 1), %%eax \
movl 20(%%ebx, %%edi, 1), %%esi \
movl %%eax, 16(%%edx, %%edi, 1) \
movl %%esi, 20(%%edx, %%edi, 1) \
movl 24(%%ebx, %%edi, 1), %%eax \
movl 28(%%ebx, %%edi, 1), %%esi \
movl %%eax, 24(%%edx, %%edi, 1) \
movl %%esi, 28(%%edx, %%edi, 1) \
subl $32, %%edi \
jge 0b \
\
movl %%ecx, %%edi \
andl $0xfffffe00, %%edi \
addl %%edi, %%ebx // increase src pointer \
addl %%edi, %%edx // increase dst pointer \
andl $31, %%ecx // new count \
jz 6f // if count = 0, get outta here \
\
1: \
cmpl $16, %%ecx \
jl 2f \
movl (%%ebx), %%eax \
movl %%eax, (%%edx) \
movl 4(%%ebx), %%eax \
movl %%eax, 4(%%edx) \
movl 8(%%ebx), %%eax \
movl %%eax, 8(%%edx) \
movl 12(%%ebx), %%eax \
movl %%eax, 12(%%edx) \
subl $16, %%ecx \
addl $16, %%ebx \
addl $16, %%edx \
2: \
cmpl $8, %%ecx \
jl 3f \
movl (%%ebx), %%eax \
movl %%eax, (%%edx) \
movl 4(%%ebx), %%eax \
subl $8, %%ecx \
movl %%eax, 4(%%edx) \
addl $8, %%ebx \
addl $8, %%edx \
3: \
cmpl $4, %%ecx \
jl 4f \
movl (%%ebx), %%eax // here 4-7 bytes \
addl $4, %%ebx \
subl $4, %%ecx \
movl %%eax, (%%edx) \
addl $4, %%edx \
4: // 0-3 remaining bytes \
cmpl $2, %%ecx \
jl 5f \
movw (%%ebx), %%ax // two bytes \
cmpl $3, %%ecx // less than 3? \
movw %%ax, (%%edx) \
jl 6f \
movb 2(%%ebx), %%al // last byte \
movb %%al, 2(%%edx) \
jmp 6f \
5: \
cmpl $1, %%ecx \
jl 6f \
movb (%%ebx), %%al \
movb %%al, (%%edx) \
6: \
popl %%esi \
popl %%edi \
"
: : "m" (src), "d" (dest), "c" (count)
: "%eax", "%ebx", "%edi", "%esi", "cc", "memory");
}
void Com_Memset (void* dest, const int val, const size_t count)
{
unsigned int fillval;
if (count < 8)
{
__asm__ __volatile__ (" \
//mov edx,dest \
//mov eax, val \
movb %%al, %%ah \
movl %%eax, %%ebx \
andl $0xffff, %%ebx \
shll $16, %%eax \
addl %%ebx, %%eax // eax now contains pattern \
//mov ecx,count \
cmpl $4, %%ecx \
jl 0f \
movl %%eax, (%%edx) // copy first dword \
addl $4, %%edx \
subl $4, %%ecx \
0: cmpl $2, %%ecx \
jl 1f \
movw %%ax, (%%edx) // copy 2 bytes \
addl $2, %%edx \
subl $2, %%ecx \
1: cmpl $0, %%ecx \
je 2f \
movb %%al, (%%edx) // copy single byte \
2: \
"
: : "d" (dest), "a" (val), "c" (count)
: "%ebx", "%edi", "%esi", "cc", "memory");
return;
}
fillval = val;
fillval = fillval|(fillval<<8);
fillval = fillval|(fillval<<16); // fill dword with 8-bit pattern
_copyDWord ((unsigned int*)(dest),fillval, count/4);
__asm__ __volatile__ (" // padding of 0-3 bytes \
//mov ecx,count \
movl %%ecx, %%eax \
andl $3, %%ecx \
jz 1f \
andl $0xffffff00, %%eax \
//mov ebx,dest \
addl %%eax, %%edx \
movl %0, %%eax \
cmpl $2, %%ecx \
jl 0f \
movw %%ax, (%%edx) \
cmpl $2, %%ecx \
je 1f \
movb %%al, 2(%%edx) \
jmp 1f \
0: \
cmpl $0, %%ecx\
je 1f\
movb %%al, (%%edx)\
1: \
"
: : "m" (fillval), "c" (count), "d" (dest)
: "%eax", "%ebx", "%edi", "%esi", "cc", "memory");
}
void Com_Prefetch (const void *s, const unsigned int bytes, e_prefetch type)
{
// write buffer prefetching is performed only if
// the processor benefits from it. Read and read/write
// prefetching is always performed.
switch (type)
{
case PRE_WRITE : break;
case PRE_READ:
case PRE_READ_WRITE:
__asm__ __volatile__ ("\
//mov ebx,s\
//mov ecx,bytes\
cmpl $4096, %%ecx // clamp to 4kB\
jle 0f\
movl $4096, %%ecx\
0:\
addl $0x1f, %%ecx\
shrl $5, %%ecx // number of cache lines\
jz 2f\
jmp 1f\
\
.align 16\
1: testb %%al, (%%edx)\
addl $32, %%edx\
decl %%ecx\
jnz 1b\
2:\
"
: : "d" (s), "c" (bytes)
: "%eax", "%ebx", "%edi", "%esi", "memory", "cc");
break;
}
}
#endif