Intel ISA Extensions

Parallel instructions for detecting MSB in array of bytes

First time posting, not sure if correct forum, but...

I have a large array of bytes, max up to 1600, but mostly up to 128.

Bytes are typically 7-bit of information, and the MSB is used as a sentinel, so the MSB is set in a small portion of the bytes.

Currently I'm looping through them in a loop, but is there a better way to use SSEx to process 128 bytes in parallel and get back a SSE vector with bits set for each byte?

Any suggestions?

Thank you,

[smp] processor disabled

I am trying to manage the multiprocessor initialization.

I found a little program [1] that implements the multiprocessor specification [2]. but in the processor entries([2] page 4-7) I get that the APs are disabled.

How can I enable the processors??
Is it a SW or HW problem ?


Thank you.
Daniel M.

LZCNT on Core i7

Let me start with: I know that LZCNT is not supported on the Core i7.

However when I run theinstruction on my Core i7 I do not as I expect get an illegal instruction exception.
Instead it performs a BSR instruction.
This is while working in 64 bit mode and using 64 bit registers.

Is this a bug, expected behaior or is running unsupported instructions undefined (and this is therefore OK)?

For reference the opcodes are:
LZCNT: 0xBD (Same as BSR but has a prefix of 0xF3)

Any feedback would be helpful.


How to multiply __m128 by a scaler?

I am just starting to work with the SSE intrinsic functions. Is there a better way to mupltiply a vector V by a scalar A than what I am doing below?

I would like to do the following u = u + (v*1.5 - vold*0.5)*delta_t;

where u, v, and vold are a vector with x, y, z, coordinates represented in a __m128.

Is there a better way to do this than to create the a, b and c values as I do in the below code? I am running on an Intel i7 computer so any options would be appreciated.

#include "stdafx.h"

CPU Serial Enable Support on Intel Processor

As per the intel documents the CPU Intel III onwards does contain the CPU Serial number.

I have tried most of the things and on multiple PC's could not able to read the serial

with EAX =3 and CPUID instruction on all PCs the CPUID is disabled ie EAX =1 and CPUID

and the EDX 18 the bit is always "0".

Does any body have any Idea how to enable the cpu serial ?

About the override of core frequency

In the datasheet of Intel CoreTM i7 Processor Extreme Edition and Intel CoreTM i7 Processor(2.4 Processor Clocking (BCLK_DP, BCLK_DN)), it says that we can override the processor core frequency setting using software. This permits operation at lower core frequencies than the factory set maximum core frequency. But I do not know how to override. Could you please tell me? vy changing the multiplier? Thanks

Why only CS, IP and EFLAGS are saved while interrupt??

I am new to assembly programming. I was reading about 386 Interrupt. I came to know that only CS, IP and EFLAGS are saved as a part of interrupt, they pop back when we have iret. But I am wondering, why they didnt save all the visible registers, segments register etc.,???

Please excuse me, if I understood something wrong.

Thanks for your effort in helping me...

E8400 with Gigabyte G41M-ES2L Motherboard

I have an E8400 with Gigabyte G41M-ES2L Motherboard I have tried to load window xp (preferred OS)on it and I get a message that there is not enough memory and windows has stopped installation. I then tried to load Windows Vista Home Basic and it worked but then after only 2 - 5 days it would crash and come back up with Windows has encountered a serious error. Then after a day or 2 it would crash and not even come up in Safe Mode. I would then reload Vista and it would repeat the same process. What is wrong? I have downloaded all the Windows Updates.

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