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Use a shorter insruction on x86 for loading unsigned 32-bit immediates into 64-bit registers. #487

Merged
merged 1 commit into from
Apr 5, 2023
Merged

Use a shorter insruction on x86 for loading unsigned 32-bit immediates into 64-bit registers. #487

merged 1 commit into from
Apr 5, 2023

Commits on Apr 4, 2023

  1. Use a shorter insruction on x86 for loading unsigned 32-bit immediate… 

    …s into 64-bit registers.

Writing into a 32-bit register erases the upper 32 bits of a 64-bit
register. This is the shortest instruction for loading unsigned
32-bit immediates. The length of those instructions is:
- movl: 5 bytes
- movq: 7 bytes
- movabsq: 10 bytes

Note: Most assemblers will choose the proper instruction by themselves;
this commit just makes this explicit.
    @valoran-M
    valoran-M committed Apr 4, 2023
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