In RV64, all values read-from-mem and write-to-mem can be viewed as 64bit because GPR and FPR are all 64bit wide. For lw/sw and flw/fsw, the simulator helper for this 4 instruction would handle the upper 32bit to a proper value.
However, for RV32, we should distinguish 32bit GPR rd/wr, 32bit FPR rd/wr and 64bit FPR rd/wr.
We can no longer depend on the templated TraceMemRd and TraceMemWr function. Because the value reg_value int 64bit for fld/fsd.
Error would happen as following picture shows, the upper 32bit would be displayed as all zeros. This would bring misunderstanding when debugging.
qjivy
commented
2 years ago 
In RV64, all values read-from-mem and write-to-mem can be viewed as 64bit because GPR and FPR are all 64bit wide. For lw/sw and flw/fsw, the simulator helper for this 4 instruction would handle the upper 32bit to a proper value.
However, for RV32, we should distinguish 32bit GPR rd/wr, 32bit FPR rd/wr and 64bit FPR rd/wr. We can no longer depend on the templated TraceMemRd and TraceMemWr function. Because the value reg_value int 64bit for fld/fsd.
Error would happen as following picture shows, the upper 32bit would be displayed as all zeros. This would bring misunderstanding when debugging.