mirror of
https://gitea.wildfiregames.com/0ad/0ad
synced 2026-07-09 16:35:47 -07:00
ffdff6888d
enable most of IA-32 specific code to be used in amd64 (resides in directory lib/sysdep/x86_x64) bits: add IsBitSet remove mem_PageSize (use os_cpu_PageSize instead) cpuid: change interface to allow gracefully supporting later subfunctions that require input parameters amd64_asm.asm: add amd64 implementation of cpuid cpu: move functions provided by OS to sysdep/os_cpu.cpp cpu topology: avoid trouble when process affinity is set by remapping processor numbers to 0..PopulationCount(processAffinity) topology.cpp: move ex-ia32 topology code here. This was SVN commit r5945.
113 lines
3.8 KiB
C++
113 lines
3.8 KiB
C++
/**
|
|
* =========================================================================
|
|
* File : ia32.cpp
|
|
* Project : 0 A.D.
|
|
* Description : routines specific to IA-32
|
|
* =========================================================================
|
|
*/
|
|
|
|
// license: GPL; see lib/license.txt
|
|
|
|
#include "precompiled.h"
|
|
#include "ia32.h"
|
|
|
|
#include "lib/sysdep/cpu.h"
|
|
#include "ia32_memcpy.h"
|
|
#include "ia32_asm.h"
|
|
|
|
|
|
LibError ia32_GetCallTarget(void* ret_addr, void** target)
|
|
{
|
|
*target = 0;
|
|
|
|
// points to end of the CALL instruction (which is of unknown length)
|
|
const u8* c = (const u8*)ret_addr;
|
|
// this would allow for avoiding exceptions when accessing ret_addr
|
|
// close to the beginning of the code segment. it's not currently set
|
|
// because this is really unlikely and not worth the trouble.
|
|
const size_t len = ~0u;
|
|
|
|
// CALL rel32 (E8 cd)
|
|
if(len >= 5 && c[-5] == 0xE8)
|
|
{
|
|
*target = (u8*)ret_addr + *(i32*)(c-4);
|
|
return INFO::OK;
|
|
}
|
|
|
|
// CALL r/m32 (FF /2)
|
|
// .. CALL [r32 + r32*s] => FF 14 SIB
|
|
if(len >= 3 && c[-3] == 0xFF && c[-2] == 0x14)
|
|
return INFO::OK;
|
|
// .. CALL [disp32] => FF 15 disp32
|
|
if(len >= 6 && c[-6] == 0xFF && c[-5] == 0x15)
|
|
{
|
|
void* addr_of_target = *(void**)(c-4);
|
|
// there are no meaningful checks we can perform: we're called from
|
|
// the stack trace code, so ring0 addresses may be legit.
|
|
// even if the pointer is 0, it's better to pass its value on
|
|
// (may help in tracking down memory corruption)
|
|
*target = *(void**)addr_of_target;
|
|
return INFO::OK;
|
|
}
|
|
// .. CALL [r32] => FF 00-3F(!14/15)
|
|
if(len >= 2 && c[-2] == 0xFF && c[-1] < 0x40 && c[-1] != 0x14 && c[-1] != 0x15)
|
|
return INFO::OK;
|
|
// .. CALL [r32 + r32*s + disp8] => FF 54 SIB disp8
|
|
if(len >= 4 && c[-4] == 0xFF && c[-3] == 0x54)
|
|
return INFO::OK;
|
|
// .. CALL [r32 + disp8] => FF 50-57(!54) disp8
|
|
if(len >= 3 && c[-3] == 0xFF && (c[-2] & 0xF8) == 0x50 && c[-2] != 0x54)
|
|
return INFO::OK;
|
|
// .. CALL [r32 + r32*s + disp32] => FF 94 SIB disp32
|
|
if(len >= 7 && c[-7] == 0xFF && c[-6] == 0x94)
|
|
return INFO::OK;
|
|
// .. CALL [r32 + disp32] => FF 90-97(!94) disp32
|
|
if(len >= 6 && c[-6] == 0xFF && (c[-5] & 0xF8) == 0x90 && c[-5] != 0x94)
|
|
return INFO::OK;
|
|
// .. CALL r32 => FF D0-D7
|
|
if(len >= 2 && c[-2] == 0xFF && (c[-1] & 0xF8) == 0xD0)
|
|
return INFO::OK;
|
|
|
|
WARN_RETURN(ERR::CPU_UNKNOWN_OPCODE);
|
|
}
|
|
|
|
|
|
void cpu_ConfigureFloatingPoint()
|
|
{
|
|
// no longer set 24 bit (float) precision by default: for
|
|
// very long game uptimes (> 1 day; e.g. dedicated server),
|
|
// we need full precision when calculating the time.
|
|
// if there's a spot where we want to speed up divides|sqrts,
|
|
// we can temporarily change precision there.
|
|
//ia32_asm_control87(IA32_PC_24, IA32_MCW_PC);
|
|
|
|
// to help catch bugs, enable as many floating-point exceptions as
|
|
// possible. unfortunately SpiderMonkey triggers all of them.
|
|
// note: passing a flag *disables* that exception.
|
|
ia32_asm_control87(IA32_EM_ZERODIVIDE|IA32_EM_INVALID|IA32_EM_DENORMAL|IA32_EM_OVERFLOW|IA32_EM_UNDERFLOW|IA32_EM_INEXACT, IA32_MCW_EM);
|
|
|
|
// no longer round toward zero (truncate). changing this setting
|
|
// resulted in much faster float->int casts, because the compiler
|
|
// could be told (via /QIfist) to use FISTP while still truncating
|
|
// the result as required by ANSI C. however, FPU calculation
|
|
// results were changed significantly, so it had to be disabled.
|
|
//ia32_asm_control87(IA32_RC_CHOP, IA32_MCW_RC);
|
|
}
|
|
|
|
|
|
void cpu_AtomicAdd(volatile intptr_t* location, intptr_t increment)
|
|
{
|
|
ia32_asm_AtomicAdd(location, increment);
|
|
}
|
|
|
|
|
|
bool cpu_CAS(volatile uintptr_t* location, uintptr_t expected, uintptr_t new_value)
|
|
{
|
|
return ia32_asm_CAS(location, expected, new_value);
|
|
}
|
|
|
|
|
|
void* cpu_memcpy(void* RESTRICT dst, const void* RESTRICT src, size_t size)
|
|
{
|
|
return ia32_memcpy(dst, src, size);
|
|
}
|