Steinar H. Gunderson: Decompilation patterns, part 10: return var_v0

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Key Architectural Takeaway

The v0 register on MIPS is special in that it is the return register (like rax is on x86-64), so when you see code like this: if (x == 3) { var_v0 = 1; } else if (y == 4) { ...

Executive Summary

The v0 register on MIPS is special in that it is the return register (like rax is on x86-64), so when you see code like this: if (x == 3) { var_v0 = 1; } else if (y == 4) { ... var_v0 = 3; } var_v0 = 5; return var_v0; then you have to consider the possibility that the intended match is: if (x == 3) { return 1; } else if (y == 4) { ... return 3; } else { return 5; } Whether you put the last return in an else block or not is irrelevant for the match, of course, it's purely a matter of taste.

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