What happens when you use comma in if/while statement [duplicate]

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• What does the comma operator , do? 8 answers

I came across following if statement which confused me. This is the output of an autogenerated .c file and compiles.

ex: while ( ( rvs_tmp_k_363=0,  RVS_DM(363,&rvs_tmp_k_363,(unsigned int)(Idx < (uint16*)&nvHist_QData[0x00FF]))))

ex: if ( ( rvs_tmp_k_362=0,  RVS_DM(362,&rvs_tmp_k_362,(unsigned int)(RVS_CM(&rvs_tmp_k_362,2,(unsigned int)((nvHist_Queue.DataPtr != (uint8*)&nvHist_QData)))