I'm developing an application in C for ConnectCore 6UL and I use some third-party libraries already compiled for ARM7.
The execution environment of the application is linux created with yocto and I have also compiled gcc to run directly on the iMX6UL.
Everything compiles correctly but when executing I get the following error and the program aborts. Illegal instruction
After checking with dgb in disassembly I see that the instruction that gives problems is the following:
0x0003e2f0 <+1112>: vabs.f32 s8, s13
0x0003e2f4 <+1116>: vdiv.f32 s14, s12, s13
0x0003e2f8 <+1120>: vdiv.f32 s15, s9, s8
0x0003e2fc <+1124>: vstr s14, [r3]
=> 0x0003e300 <+1128>: vrintz.f32 s15, s15
0x0003e304 <+1132>: vmul.f32 s15, s15, s8
0x0003e308 <+1136>: vcvt.s32.f32 s15, s15
0x0003e30c <+1140>: vmov r12, s15
0x0003e310 <+1144>: cmp r12, #1
This instruction is located within the memory space of the library that I have commented on previously.
I have created this little program:
#include <stdio.h>
int main ()
{
printf ("1\n");
asm ("vrintz.f32 s15, s15");
printf ("2\n");
return 1;
}
And gcc tells me the following:
# gcc test.c
/tmp/ccEGrRl1.s: Assembler messages:
/tmp/ccEGrRl1.s:45: Error: selected processor does not support `vrintz.f32 s15,s15' in ARM mode
Is it possible that this instruction is not supported by iMX6UL? do i need any additional flag for compiling?
I have also tried from the cross compiler using the following flags obtaining the same result:
arm-dey-linux-gnueabi-gcc -mthumb -mfpu=neon -mfloat-abi=hard -mcpu=cortex-a7 -fstack-protector-strong -Wformat -Wformat-security -Werror=format-security - -sysroot=/opt/dey/3.2-r1/ccimx6ulsbc/sysroots/cortexa7t2hf-neon-dey-linux-gnueabi
As additional information, I have tested the same source code and compiled library for a raspberry pi 4b and it works perfectly.
Any suggestion?
