From 4ad250c85a1abb80b6e0a30855c8982d174b369c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Fri, 19 Jan 2018 12:37:49 +0100
Subject: Optimize matching of empty binaries

Extend an existing optimization in beam_dead to avoid
creating a match context when matching an empty binary.
---
 lib/compiler/test/bs_match_SUITE.erl | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'lib/compiler/test')

diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl
index 4bd5e8e2e1..235956a714 100644
--- a/lib/compiler/test/bs_match_SUITE.erl
+++ b/lib/compiler/test/bs_match_SUITE.erl
@@ -678,6 +678,10 @@ coverage(Config) when is_list(Config) ->
     <<>> = coverage_per_key(<<4:32>>),
     <<$a,$b,$c>> = coverage_per_key(<<7:32,"abc">>),
 
+    binary = coverage_bitstring(<<>>),
+    binary = coverage_bitstring(<<7>>),
+    bitstring = coverage_bitstring(<<7:4>>),
+    other = coverage_bitstring([a]),
     ok.
 
 coverage_fold(Fun, Acc, <<H,T/binary>>) ->
@@ -768,6 +772,10 @@ coverage_per_key(<<BinSize:32,Bin/binary>> = B) ->
     true = (byte_size(B) =:= BinSize),
     Bin.
 
+coverage_bitstring(Bin) when is_binary(Bin) -> binary;
+coverage_bitstring(<<_/bitstring>>) -> bitstring;
+coverage_bitstring(_) -> other.
+
 multiple_uses(Config) when is_list(Config) ->
     {344,62879,345,<<245,159,1,89>>} = multiple_uses_1(<<1,88,245,159,1,89>>),
     true = multiple_uses_2(<<0,0,197,18>>),
-- 
cgit v1.2.3


From 1781ebe6cd61d0bbd1f8c4e55b42edebfdc45734 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Fri, 19 Jan 2018 14:38:54 +0100
Subject: beam_type: Optimize away unnecessary test_unit instructions

Optimize away unnecessary test_unit instructions that verify that
binaries are byte-aligned. In a tight loop, eliminating an
instruction can have a small but measurable improvement of the
execution time.
---
 lib/compiler/test/beam_type_SUITE.erl | 42 +++++++++++++++++++++++++++++++++--
 1 file changed, 40 insertions(+), 2 deletions(-)

(limited to 'lib/compiler/test')

diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl
index fe856b12b6..dfbf2aa4a0 100644
--- a/lib/compiler/test/beam_type_SUITE.erl
+++ b/lib/compiler/test/beam_type_SUITE.erl
@@ -23,7 +23,7 @@
 	 init_per_group/2,end_per_group/2,
 	 integers/1,coverage/1,booleans/1,setelement/1,cons/1,
 	 tuple/1,record_float/1,binary_float/1,float_compare/1,
-	 arity_checks/1]).
+	 arity_checks/1,elixir_binaries/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
@@ -42,7 +42,8 @@ groups() ->
        record_float,
        binary_float,
        float_compare,
-       arity_checks
+       arity_checks,
+       elixir_binaries
       ]}].
 
 init_per_suite(Config) ->
@@ -199,5 +200,42 @@ do_tuple_arity_check(RGB) when is_tuple(RGB),
         _ -> ok
     end.
 
+elixir_binaries(_Config) ->
+    <<"foo blitzky baz">> = elixir_binary_1(<<"blitzky">>),
+    <<"foo * baz">> = elixir_binary_2($*),
+    <<7:4,755:10>> = elixir_bitstring_3(<<755:10>>),
+    ok.
+
+elixir_binary_1(Bar) when is_binary(Bar) ->
+    <<"foo ",
+      case Bar of
+          Rewrite when is_binary(Rewrite) ->
+              Rewrite;
+          Rewrite ->
+              list_to_binary(Rewrite)
+      end/binary,
+      " baz">>.
+
+elixir_binary_2(Arg) ->
+    Bin = <<Arg>>,
+    <<"foo ",
+      case Bin of
+          Rewrite when is_binary(Rewrite) ->
+              Rewrite;
+          Rewrite ->
+              list_to_binary:to_string(Rewrite)
+      end/binary,
+      " baz">>.
+
+elixir_bitstring_3(Bar) when is_bitstring(Bar) ->
+    <<7:4,
+      case Bar of
+          Rewrite when is_bitstring(Rewrite) ->
+              Rewrite;
+          Rewrite ->
+              list_to_bitstring(Rewrite)
+      end/bitstring>>.
+
+
 id(I) ->
     I.
-- 
cgit v1.2.3