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vmt / udis86

Disassembler Library for x86 and x86-64
http://udis86.sourceforge.net
BSD 2-Clause "Simplified" License
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ATT syntax decode is ambiguous #113

Open robertwhitton opened 8 years ago

robertwhitton commented 8 years ago

In the function ud_translate_att "size" is initialised to zero and isn't subsequently set. Consequently some instructions decode ambiguously and it isn't possible to determine the size of the operation. For example a "mov" instruction with operands of the following type:

mov UD_OP_IMM, UD_OP_MEM

For cases such as this size of the operation is ambiguous in the disassembly.

I suggest that udis86 takes a lead from objdump and for such ambiguous cases appends b, w, l, q to the mnemonic as appropriate. For the case above (and I don't know if there are other similar cases) the attached patch appears to be helpful:

patch.txt

robertwhitton commented 8 years ago

Another set of cases are the single operand instructions such as "not" with an operand of type UD_OP_MEM, New patch attached.

patch2.txt

robertwhitton commented 8 years ago

Yet more cases come to light. All candidate changes attached:

patch3.txt