Move rewriting of bs_match from beam_clean to beam_z

The actual bs_match_string instruction has four operands:

   bs_match_string {f,Lbl} Ctxt NumBits {string,ListOfBytes}

However, v3_codegen emits a more compact representation where
the bits to match are packaged in a bitstring:

   bs_match_string {f,Lbl} Ctxt Bitstring

Currently, beam_clean:clean_labels/1 will rewrite the compact
representation to the final representation. That is unfortunate
since clean_labels/1 is called by beam_dead, which means that
the less compact representation will be introduced long before
it is actually needed by beam_asm. It will also complicate any
optimizations that we might want to do.

Move the rewriting of bs_match_string from beam_clean:clean_labels/1
to the beam_z pass, which is the last pass executed before
beam_validator and beam_asm.

1 files changed, 0 insertions, 8 deletions

diff --git a/lib/compiler/src/beam_clean.erl b/lib/compiler/src/beam_clean.erl
index b68b8702e0..1d26993103 100644
--- a/lib/compiler/src/beam_clean.erl
+++ b/lib/compiler/src/beam_clean.erl
@@ -184,14 +184,6 @@ function_replace([{function,Name,Arity,Entry,Asm0}|Fs], Dict, Acc) ->
     function_replace(Fs, Dict, [{function,Name,Arity,Entry,Asm}|Acc]);
 function_replace([], _, Acc) -> Acc.
 
-replace([{test,bs_match_string=Op,{f,Lbl},[Ctx,Bin0]}|Is], Acc, D) ->
-    Bits = bit_size(Bin0),
-    Bin = case Bits rem 8 of
-	      0 -> Bin0;
-	      Rem -> <<Bin0/bitstring,0:(8-Rem)>>
-	  end,
-    I = {test,Op,{f,label(Lbl, D)},[Ctx,Bits,{string,binary_to_list(Bin)}]},
-    replace(Is, [I|Acc], D);
 replace([{test,Test,{f,Lbl},Ops}|Is], Acc, D) ->
     replace(Is, [{test,Test,{f,label(Lbl, D)},Ops}|Acc], D);
 replace([{test,Test,{f,Lbl},Live,Ops,Dst}|Is], Acc, D) ->