Is it possible to get this SSA IR of an Elixir module?
jackalcooper
al2o3cr
It’s possible to generate it for an Elixir file using @compile (tip from this issue):
# in foo.ex
defmodule Foo do
@compile :dprecg
def foo(a, b) do
a + b
end
end
then compiling with elixir foo.ex complains:
$ elixir foo.ex
** (CompileError) foo.ex: could not compile module Foo. We expected the compiler to return a .beam binary but got something else. This usually happens because ERL_COMPILER_OPTIONS or @compile was set to change the compilation outcome in a way that is incompatible with Elixir
but does produce a foo.ex.precodegen file:
# foo.ex.precodegen
module 'Elixir.Foo'.
exports [{'__info__',1},{foo,2},{module_info,0},{module_info,1}].
attributes [].
%% Counter = 16
function `'Elixir.Foo'`:`'__info__'`(x0/_0) {
%% _0: 0..1 0..2 10..11 14..15
0:
[1] switch x0/_0, ^3, [
{ `attributes`, ^13 },
{ `compile`, ^13 },
{ `deprecated`, ^8 },
{ `exports_md5`, ^10 },
{ `functions`, ^9 },
{ `macros`, ^8 },
{ `md5`, ^13 },
{ `module`, ^7 }
]
7:
[3] ret `'Elixir.Foo'`
9:
[5] ret `[{foo,2}]`
10:
[7] ret `<<63,179,243,139,216,207,23,209,142,119,33,235,17,74,57,60>>`
8:
[9] ret `[]`
13:
%% @ssa_ret:6: 11..13
[11] x0/@ssa_ret:6 = call (`erlang`:`get_module_info`/2), `'Elixir.Foo'`, x0/_0
[13] ret x0/@ssa_ret:6
3:
%% @ssa_ret:14: 15..17
[15] x0/@ssa_ret:14 = match_fail `function_clause`, x0/_0
[17] ret x0/@ssa_ret:14
}
%% foo.ex:4
%% Counter = 4
function `'Elixir.Foo'`:`foo`(x0/_0, x1/_1) {
%% _0: 0..1
%% _1: 0..1
0:
%% foo.ex:5
%% _2: 1..7
[1] x0/_2 = bif:'+' x0/_0, x1/_1
%% @ssa_bool: 3..5
[3] z0/@ssa_bool = succeeded x0/_2
[5] br z0/@ssa_bool, ^3, ^1
3:
[7] ret x0/_2
1:
%% @ssa_ret: 9..11
[9] x0/@ssa_ret = call (`erlang`:`error`/1), `badarg`
[11] ret x0/@ssa_ret
}
%% Counter = 4
function `'Elixir.Foo'`:`module_info`() {
0:
%% @ssa_ret:3: 1..3
[1] x0/@ssa_ret:3 = call (`erlang`:`get_module_info`/1), `'Elixir.Foo'`
[3] ret x0/@ssa_ret:3
}
%% Counter = 4
function `'Elixir.Foo'`:`module_info`(x0/_0) {
%% _0: 0..1
0:
%% @ssa_ret:3: 1..3
[1] x0/@ssa_ret:3 = call (`erlang`:`get_module_info`/2), `'Elixir.Foo'`, x0/_0
[3] ret x0/@ssa_ret:3
}
1
olafura
Of course but the further you get away from something similar to Erlang the harder it is to have Elixir code that makes sense. That is why I choose to translate the Erlang AST to Elixir and even then there are some things that is hard to create nice code from.
0
jackalcooper
Agree. What I want to explore is to represent the Erlang SSA IR in MLIR. So that I can lower it to LLVM and further anything LLVM supports.
0