These optimizations were already present, but only when d == a. They
also make sense when this condition does not hold.
- imm == 0
Before:
41 BB 00 00 00 00 mov r11d,0
45 2B DF sub r11d,r15d
After:
45 8B DF mov r11d,r15d
41 F7 DB neg r11d
- imm == -1
Before:
41 BD FF FF FF FF mov r13d,0FFFFFFFFh
44 2B EE sub r13d,esi
0F 93 45 68 setae byte ptr [rbp+68h]
After:
44 8B EE mov r13d,esi
41 F7 D5 not r13d
C6 45 68 01 mov byte ptr [rbp+68h],1
18aaf488b0