Questions tagged [bytecode]
"bytecode" is a blanket term for opcodes that are consumed by a virtual machine. For example, the JVM runs bytecode stored in .class files and the CPython interpreter runs bytecode stored in .pyc files.
bytecode
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Python bytecode, does compare_op pop the stack?
I'm working with the following bytecode:
6 10 LOAD_FAST 0 (x)
12 LOAD_CONST 3 (255)
14 COMPARE_OP 2 (<)
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Assistance Needed with eBPF Conformance Test: Understanding Offset Calculations for ldxh and ldxw Operations [closed]
I'm currently working on an eBPF specification and have encountered some issues due to the lack of documentation. I'm using the conformance tests available in the https://github.com/Alan-Jowett/...
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Why is the eBPF compiler behaving differently when not using bpf_map_update_element()
I have eBPF code where I lookup a certain structure from a map, and then access a field inside that structure, and make modifications to the values inside the structure. eBPF generates the following ...
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Where to find jdk sources for JNI_CreateJavaVM?
I'm trying to understand better how jvm works, and I was trying to find the main function that really interested me - the JNI_CreateJavaVM function. I wonder how it parses java bytecode, but I can't ...
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How to change result type id while reserving the literal value of OpConstant in Spir-V?
I am writing a Spir-v processor, which is intended to create a new OpTypeFloat with a width of 16 bits and then change the result type ids of the existing OpConstants to the result id of the created, ...
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How to print out the literal value of a Spir-V OpConstant?
I am have a Spir-V parser from Github, which is capable of processing and modifying the Spir-V binary. At the moment, I just would like to print out the literal value of the OpConstant variables.
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What is the use of __pycache__ bytecode version of my file when the file itself is deleted?
I am playing around with import mechanism. Here's what happened:
dir/b.py -> Prints "hello"
dir/a.py --> Imports b.py
For the first time, when I imported b (from a.py), a directory ...
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How to decode packet length from variable number of bytes?
I am intercepting data from one application, it accepts binary data in the form of packets of information. At the beginning of each packet, depending on the length of the packet, there are 1, 2 or 3 ...
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Unexpected `NoClassDefFoundError` when optional library is not on classpath, but related code is not executed
I am trying to use the Google Closure Compiler from Java code, but want it to be an optional dependency (present at build time, but may not be around when deployed).
The problem I'm having is that I'm ...
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How to get the result id type of an OpConstant in Spir-V?
I am writing a Spir-V parser, which will be capable of iterating through the bytecode and change the Result Type id of float variables. Actually I want to convert fp32 variables to fp16.
I wrote this ...
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Python virtual machine and bytecode
I am trying to fully understand the structure of PYC file. But I can't understand how FLAG_REF works and what it affects, its meaning.
https://github.com/python/cpython/blob/3.6/Python/marshal.c#L952
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How does one disassemble Python graal bytecode?
I have been considering extending the cross-version python disassembler xdis for Python Graal.
GraalPython provides a Python Code type that is similar to Python's Code type, but the underlying ...
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Decompiling Lua Issue
I'm working with the game GeminiLost from playfirst, they have an assets.pfp file that can be extracted using a BMS Script
After extraction it is possible to see lua scripts that were compiled using ...
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What's this error and how can I fix it? - java.lang.VerifyError: Bad local variable type
I'm implementing a YamlParser in Kotlin with Cojen Maker and we've stumbled upon a roadblock and have no idea of what this error is or why it's happening
We think it has something to do with the type ...
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Can a Java inner class have static initialization in bytecode?
This is NOT the same question as:
Why can't an inner class use static initializer?
or other similar ones, since it's unrelated to the Java language semantics and relates purely to bytecode and the ...
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