Intel ISA Extensions

PUSH and POP of XMM/YMM registers


I have written a function in that AVX2 instructions are using XMM/YMM registers. Due to use of some of these registers in this function, causing other part of application is crashing. I have observed strange behavior is that If these registers are pushed and popped as like non-volatile general purpose registers are pushed and popped.

Please help me whether, we need to push and pop the SIMD registers also. If so all XMM/YMM registers are needs to be saved and how?

instructional change __m128i

Hi, good afternoon.

I am using a __m128i for store 16 elements of 8 bits

__m128i s0 = _mm_set_epi8(pixelsTemp[95], pixelsTemp[94], pixelsTemp[93], pixelsTemp[92], pixelsTemp[91], pixelsTemp[90], pixelsTemp[89], pixelsTemp[88], pixelsTemp[87], pixelsTemp[86], pixelsTemp[85], pixelsTemp[84], pixelsTemp[83], pixelsTemp[82], pixelsTemp[81], pixelsTemp[224]);

SDE emulation issue

I am using the SDE emulator with AVX2 instruction set, I have written some simple program but it is crashing in RELEASE mode with SDE emulator.

Please let me know whether SDE emulates the stack related operations or not.  YASM synatxed assembly programming

section .txt
 global dummy_asm

    push rbp
    mov  rbp, rsp
    sub rsp, 1024
    push rbx ;no need to push in this program, but in actual program using this register
    vmovdqu [rsp], xmm0 ;xmm0 is dummy value

    pop rbx

Broken links for MPX GCC version on the Intel server?

I'm not sure where else to post issues with downloads so I'm just posting it here. At the following URL I'm trying to download the patched version of GCC. The download, however, stops before it is finished. I have tried to download these files from different physical systems, using e.g. Firefox and wget; just to exclude issues on my side. Is there any more recent static version of GCC with MPX available?

AVX _mm256_store_ps


I am wanting to run the following code using the AVX instruction set,

 I compile without any problem but generates an error when I run:


"Segmentation fault (core dumped)"

Reviewing the code the problem is in the instruction: 

  _mm256_store_ps(&total,acc); //Error

Could someone point me to to be.

Thank you


I compile with the following command: 

gcc -O3 vec_avx.c -mavx -o vec_avx.x

And the main code is as follows:

Intel MPX, unable to reproduce results in example

In trying to reproduce the example given by Ady Tal at I encounter the following problem:

Terminal 1:

$ ../sde-external-6.22.0-2014-03-06-lin/sde64 -mpx-mode -debug -- ./mpx_test3
Application stopped until continued from debugger.
Start GDB, then issue this command at the (gdb) prompt:
  target remote :44736

Terminal 2:

SIGILL on AVX instruction


I have a very simple test program that I'm using to play around with AVX instruction sets. It works perfectly fine on my MacBook Pro, however, the same piece of code will fire off a SIGILL on my Linux workstation. I check cpuid before invoking the instructions and /proc/cpuinfo is also has the AVX flag set. I'm using clang with the -mavx command line switch. The instructions throwing the exception are any _mm256_xxx ones. I'm not using the FMA instructions. /proc/cpuinfo says I have 12 cores of Intel(R) Xeon(R) CPU E5-1660 0 @ 3.30GHz.



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