Fix disassembly error in issue #193 #195
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…ass at disasm/disasm.c:1519 Incorrect ordering led to specific encoding for implicit shift by one (M1 - UNITY from include/opflags.h & x86/insnsd.c) being skipped over in disasm.c:1519. The skip over the UNITY block would lead to the code ending up at disasm.c:1569, adding 0x0 to the end of the instruction and moving onwards having emitted the incorrect instruction. The correction of is_class is consistent with other usage of is_class in the disasm.c file and its signature in include/opflags.h ( static inline bool is_class(opflags_t class, opflags_t op) ); the error was placement of t in class and unity in op respectively.
…the branch runs through the test workflow.
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The specific issue was caused by incorrect placement of operands in is_class in disasm.c
The issue fixes the specific bug shown in the issue as well as for the same instructions with a larger register size. The initial push itself has a commit with more technical details:
3ec5afd
"Fixed issue #193 by switching operand order of is_class at disasm/disasm.c:1519
Incorrect ordering led to specific encoding for implicit shift by one (M1 - UNITY from include/opflags.h & x86/insnsd.c) being skipped over in disasm.c:1519.
The skip over the UNITY block would lead to the code ending up at disasm.c:1569, adding 0x0 to the end of the instruction and moving onwards having emitted the incorrect instruction.
The correction of is_class is consistent with other usage of is_class in the disasm.c file and its signature in include/opflags.h ( static inline bool is_class(opflags_t class, opflags_t op) ); the error was placement of t in class and unity in op respectively."
Thank you for reading this and let me know if you need any changes or anything else involving this. I did forget to turn on the workflow runner when I forked this repository so I needed to just make a push to the branch so it would run and test the changes, so those are the extra two commits after the first commit.