Displaying 2 results from an estimated 2 matches for "jump_destination1".
2013 Jun 28
3
[LLVMdev] Question regarding the x86 SBB instruction.
Hi,
I have the x86 SBB instruction. how should I represent this in LLVM
IR. (as part of a decompiler from binary to LLVM IR)
Pre-conditions:
%eax = 0xffffffff
%edx = 0xffffffff
%carry = 1
SBB %eax, %edx // %edx is the destination doing %edx = %edx -
(%eax + carry)
JC jump_destination1 // If the Carry flag is set, jump to jump_destination1
How do I represent this correctly in LLVM IR?
In the above case, the carry flag should be set by the SBB because:
%eax + carry == 0x100000000 (33 bits) or 0x0 (32 bits)
%edx - (%eax + carry) == %edx with Carry set.
If I use LLVM IR:...
2013 Jun 28
0
[LLVMdev] Question regarding the x86 SBB instruction.
...uction. how should I represent this in LLVM
> IR. (as part of a decompiler from binary to LLVM IR)
>
> Pre-conditions:
> %eax = 0xffffffff
> %edx = 0xffffffff
> %carry = 1
>
> SBB %eax, %edx // %edx is the destination doing %edx = %edx -
> (%eax + carry)
> JC jump_destination1 // If the Carry flag is set, jump to jump_destination1
>
> How do I represent this correctly in LLVM IR?
> In the above case, the carry flag should be set by the SBB because:
> %eax + carry == 0x100000000 (33 bits) or 0x0 (32 bits)
> %edx - (%eax + carry) == %edx with Carr...