What does this instruction do? Does it change the value of edx to 0?
lea edx, 0[0+rax*4]
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1No, read the manual for `LEA`. It's a copy-and-shift. – Peter Cordes Apr 05 '20 at 06:06
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No, it's putting rax*4 into edx. Very similiar to `mov edx,eax; lsh edx,2;`, but the flags might be different. – Robert McKee Apr 05 '20 at 06:33
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1@Robert McKee: It is called `shl`. And `lea` does not alter any of the status flags. – ecm Apr 05 '20 at 10:56
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No, it doesn't. The lea (load effective address) instruction is used to put a memory address into the destination.
For example, here, you are going to put 0[0+rax*4] in edx.
Syntax:
lea destination, source
This will help you: https://www.aldeid.com/wiki/X86-assembly/Instructions/lea
Also this: What do the brackets mean in x86 asm?
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