feat: Baseline JIT implementation

[xxuejie]

NOTE: this PR is quite huge but there are certain files(which contribute to more than half the changes here) we don't need to review:

• Files in dynasm folder are pulled directly from official LuaJIT, there's no modification by us.
• src/jit/asm.x64.compiled.c is translated from src/jit/asm.x64.c. Ideally, we might want to exclude this file and only generate it in build steps. But the problem is the translator here is written in Lua, and requires a real Lua binary to run it. As of now, there's no easy way to build a binary, then execute it in build.rs. Hence for simplicity reason, I just included src/jit/asm.x64.compiled.c here, in the future we might want to build a separate crate packaging Lua binary and dynasm translator here to handle this task.

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Closes #20

[doitian]

For src/jit/asm.x64.compiled.c, I think we can add a Makefile rule to compile it using the system Lua to ease maintenance. E.g.

LUA := lua

src/jit/asm.x64.compiled.c: src/jit/x.lua src/jit/asm.x64.c
	$LUA $+

[xxuejie]

For src/jit/asm.x64.compiled.c, I think we can add a Makefile rule to compile it using the system Lua to ease maintenance. E.g.

LUA := lua

src/jit/asm.x64.compiled.c: src/jit/x.lua src/jit/asm.x64.c
	$LUA $+

Yeah this would work(and we can actually just submodule LuaJIT this way as well), but my question is: is it common practice to require a Makefile and gcc(yeah I think it's better for us to require gcc and compile Lua as needed instead of requiring system Lua) for a Rust crate? Also that means we won't be able to compile this crate with cargo alone, is that gonna be a concern?

Also, should we choose to go forward with it, this new Makefile-based process is gonna affect CKB as well.

[doitian]

Yeah this would work(and we can actually just submodule LuaJIT this way as well), but my question is: is it common practice to require a Makefile and gcc(yeah I think it's better for us to require gcc and compile Lua as needed instead of requiring system Lua) for a Rust crate? Also that means we won't be able to compile this crate with cargo alone, is that gonna be a concern?

Also, should we choose to go forward with it, this new Makefile-based process is gonna affect CKB as well.

No, the compilation does not depend on GCC and Lua, just keep src/jit/asm.x64.compiled.c in the repo. The command just helps developers to update the file. It also can be added in CI to ensure the two files are synchronized.

[xxuejie]

Yeah this would work(and we can actually just submodule LuaJIT this way as well), but my question is: is it common practice to require a Makefile and gcc(yeah I think it's better for us to require gcc and compile Lua as needed instead of requiring system Lua) for a Rust crate? Also that means we won't be able to compile this crate with cargo alone, is that gonna be a concern?
Also, should we choose to go forward with it, this new Makefile-based process is gonna affect CKB as well.

No, the compilation does not depend on GCC and Lua, just keep src/jit/asm.x64.compiled.c in the repo. The command just helps developers to update the file. It also can be added in CI to ensure the two files are synchronized.

This is a very neat idea 👍 , already added Makefile rules and CI target.

Wrong comment