Does V8 engine know how to print generated machine code using Intel syntax?

Question

I'm using D8 shell and the flag --print-opt-code to print the code TurboFan generates.

However, the code is printed using AT&T syntax. I'm not familiar with it, but with Intel syntax. I searched in d8 --help and didn't find an option for this. Does V8 have an option to print the assembly using Intel syntax? If not, is there a workaround, such as a program that I can run together with D8 to convert the AT&T to Intel syntax?

score 1 · Accepted Answer · answered Nov 16 '20 at 19:16

1

(V8 developer here.)

V8 supports only one syntax for printing disassembly. It's very close to Intel syntax: destination before source (e.g. movl eax, 2), indirect memory addresses like [eax+ebx*2+1].

Looking at https://en.wikipedia.org/wiki/X86_assembly_language#Syntax for reference, I suppose you could say that the one convention V8 takes from AT&T syntax is that operation width is encoded as a suffix of the instruction name, e.g. movl is a 4-byte move, movq is an 8-byte move, testb is a 1-byte test.

answered Nov 16 '20 at 19:16

jmrk

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After I asked the question, I noticed the similarities to Intel syntax, but the suffixes confused me... So are you saying that this is a distinct syntax? – Chayim Friedman Nov 16 '20 at 19:19
I'd call it "Intel syntax", you can call it whatever you like if you don't agree with that description :-) – jmrk Nov 16 '20 at 20:06
Why do the V8 developers complicate simple things :P – Chayim Friedman Nov 16 '20 at 20:07

Does V8 engine know how to print generated machine code using Intel syntax?

1 Answers1