Merge branch 'bjorn/compiler/ssa'

* bjorn/compiler/ssa:
  Travis CI: Run the SSA linter in the Linux64SmokeTest build
  Remove retired compiler passes
  Introduce a new SSA-based intermediate format
  hipe_beam_to_icode: Correct translation of get_map_elements
  beam_dead: Remove shortcut of binary matching instruction
  beam_bs: Remove optimizations that are easier done on SSA format
  Don't run unsafe compiler passes
  Simplify optimizations by introducing is_nil late
  beam_utils: Make is_tagged_tuple a pure test
  beam_except: Enhance recognition of function_clause exceptions
  beam_validator: Infer the types of copies in a smarter way
  beam_validator: Improve merge of cons and literal list
  beam_validator: Strengthen validation of func_info
  beam_validator: Allow get_tuple_element before dsetelement
  beam_validator: Don't transfer state to labels that can't be reached
  beam_validator: Improve type analysis for tuples
  beam_validator: Be more careful when updating try/catch state
  beam_trim: Handle an empty list of instructions
  v3_core: Number argument variables in ascending order
  Teach binary instructions to use Y registers as destination

OTP-14894

1 files changed, 38 insertions, 0 deletions

diff --git a/lib/compiler/test/receive_SUITE_data/ref_opt/no_5.erl b/lib/compiler/test/receive_SUITE_data/ref_opt/no_5.erl
new file mode 100644
index 0000000000..4fbde3a83d
--- /dev/null
+++ b/lib/compiler/test/receive_SUITE_data/ref_opt/no_5.erl
@@ -0,0 +1,38 @@
+-module(no_5).
+-compile([export_all,nowarn_export_all]).
+
+?MODULE() ->
+    ok.
+
+%% Nested receives were not handled properly.
+
+confusing_recv_mark(Pid) ->
+    Ref = make_ref(),
+    %% There would be a recv_mark here.
+    MRef = erlang:monitor(process, Pid),
+    receive
+        Ref ->
+            %% And a recv_set here.
+            receive
+                MRef -> gurka
+            end;
+        MRef ->
+            gaffel
+    end.
+
+%% The optimization could potentially be improved to
+%% handle matching of multiple refs, like this:
+
+proper_recv_mark(Pid) ->
+    %% Place the recv_mark before the creation of both refs.
+    Ref = make_ref(),
+    MRef = erlang:monitor(process, Pid),
+    %% Place the recv_set here.
+    receive
+        Ref ->
+            receive
+                MRef -> gurka
+            end;
+        MRef ->
+            gaffel
+    end.