Issue mentioned: https://github.com/riscv/riscv-code-size-reduction/issues/182
The order of callee-saved registers stored by Zcmp push in memory is reversed.
Pseudo code for cm.push in https://github.com/riscv/riscv-code-size-reduction/releases/download/v1.0.4-1/Zc.1.0.4-1.pdf
if (XLEN==32) bytes=4; else bytes=8; addr=sp-bytes; for(i in 27,26,25,24,23,22,21,20,19,18,9,8,1) { //if register i is in xreg_list if (xreg_list[i]) { switch(bytes) { 4: asm("sw x[i], 0(addr)"); 8: asm("sd x[i], 0(addr)"); } addr-=bytes; } }
The placement order for push is s11, s10, ..., ra.
CFI offset should be calculed as reversed order for correct stack unwinding.