Unnecessary mov eax, eax generated only if there is a conditional branch. #167795
Description
https://godbolt.org/z/48scbhEKo
Code
int eax(); unsigned long long x(int in) { in |= eax(); if (in < 0) { while (true) {} } return (unsigned long long)(unsigned)in; } unsigned long long y(int in) { in |= eax(); return (unsigned long long)(unsigned)in; }Assembly
x(int): push rbx mov ebx, edi call eax()@PLT or eax, ebx js .LBB0_1 mov eax, eax ; <--- pop rbx ret .LBB0_1: jmp .LBB0_1 y(int): push rbx mov ebx, edi call eax()@PLT or eax, ebx pop rbx ret```