Error while using HDL coder: variable-size matrix type is not supported for HDL code generation

please help!!

function [alphaijVHDL]=Inter_func(betaijVHDL,alphaijVHDL,EN_sp_i,sgn,pas,s2,sp,threshold)

temp1=0;

betaijSP=zeros(1,1152);

alphaijSP=zeros(1,1152);

for isp=0:sp-1

betaijSP=betaijVHDL(1+(pas+pas*(isp-1)) : pas+pas*isp);

coder.varsize('betaijSP',[1 1152]);

val1=betaijSP(betaijSP~=0);

dlin2=length(val1);

val3=zeros(1,dlin2);

if dlin2>=1

for j=1:dlin2

val2=val1;

val2=abs(val2);

val2(j)=10000;

min_local=min(val2);

%******************************************

if isp==0

if min_local<=threshold

val3(j)=s2*sgn(j+temp1)*min(val2);

elseif EN_sp_i(isp+2)==1

val3(j)=s2*sgn(j+temp1)*threshold;

else

val3(j)=s2*sgn(j+temp1)*min(val2);

end

else

if min_local<=threshold

val3(j)=s2*sgn(j+temp1)*min(val2);

elseif EN_sp_i(isp)==1

val3(j)=s2*sgn(j+temp1)*threshold;

else

val3(j)=s2*sgn(j+temp1)*min(val2);

end

end

end

alphaijSP=alphaijVHDL(1+(pas+pas*(isp-1)) : pas+isp*pas);

alphaijSP(betaijSP~=0)=val3;

alphaijVHDL(1+(pas+pas*(isp-1)) : pas+isp*pas)=alphaijSP;

end

temp1=dlin2+temp1;

end

end

Answer 1

[Bilal MEJMAA]

Thank you so much for your answer

In general I need to split an Input vector into two partitions and process each partition inside the "for isp=0:sp-1" boucle (Line5) according to the other input parameters, then fed the output with the same size of the input vector.

[Kiran Kintali]

Thanks for sharing the design and the testbench.

for ii=1:n
% body of the loop
end

for such loops 'n' needs to be compile time constant. In your example 'sp' variable is defined as a variable (not a coder.Constant). You can change the variable 'sp' to an example constant in the input variable table and choose define as Constant.

If you keep this loop bound as a variable the number of iterations are not fixed and hence not synthesizable to hardware.

Similarly betaijSP is defined as a variable sized variable. Such dynamic sized variables are not currently supported for HDL code generation as they not synthesizable.

[Bilal MEJMAA]

Thank you for your support Mr Kiran ,

I defined 'sp' as coder.Constant but I still have the Error that coder.Constant type does not support the parameter ':' I am still wondering how can I set loops in the program.

Answer 2

[Kiran Kintali]

Can you please share design (Inter_func.m) and testbench (Inter_func_tb.m) driving the design with valid inputs and the HDL Coder project file (.prj) with code generation settings?

HDL Code generation requires static matrix types (i.e., variable assignments should not change sizes dynamically) for successful hardware synthesis. The design seem to be changing variable sizes between multiple assignments or output sizes are not determinable with input sizes to operators and depend on the run time values of the variables.

[Achala G]

HDL Conformance check complete with 23 errors, 0 warnings, and 4 messages.

Function LocationLevelDescription

eucleds_verilog_fixpt:55Error'var1' : HDL code generation does not support variable-size matrix type

eucleds_verilog_fixpt:55Error'res' : HDL code generation does not support variable-size matrix type

eucleds_verilog_fixpt:55Error'hfi' : HDL code generation does not support variable-size matrix type.

I have defined some of variables like

coder.varsize('X',[1 10]);

coder.varsize('Y',[1 10]);

inside the matlab code. Still i get above error while running HDL code generation part.

Could you please help me in solving above issue?

Since I have written code for polynomial devision and hence each time quotient and reminder polynomial size varies.

[Kiran Kintali]

Can you share your model?

You would need to review the data type inference related issues. You can use code generation report for the MATLAB constructs in question and remove unsynthesizable variable matrix types. The code generation report is accessible in MATLAB function block and MATLAB to HDL workflows.