Add the beam_except pass to optimize exceptions

In order to save space, rewrite suitable calls to erlang:error/{1,2}
to special BEAM instructions.

This code is probably longer than the code taken out of v3_life and
v3_codegen in the previous commit, but it is much easier to
understand and maintain since the BEAM assembler format is better
understood than the v3_life format.

3 files changed, 87 insertions, 2 deletions

diff --git a/lib/compiler/test/Makefile b/lib/compiler/test/Makefile
index b90adaf917..2ea50b9112 100644
--- a/lib/compiler/test/Makefile
+++ b/lib/compiler/test/Makefile
@@ -10,6 +10,7 @@ MODULES= \
 	apply_SUITE \
 	beam_validator_SUITE \
 	beam_disasm_SUITE \
+	beam_expect_SUITE \
 	bs_bincomp_SUITE \
 	bs_bit_binaries_SUITE \
 	bs_construct_SUITE \
@@ -39,6 +40,7 @@ MODULES= \
 NO_OPT= \
 	andor \
 	apply \
+	beam_expect \
 	bs_construct \
         bs_match \
 	bs_utf \
diff --git a/lib/compiler/test/beam_expect_SUITE.erl b/lib/compiler/test/beam_expect_SUITE.erl
new file mode 100644
index 0000000000..6f216eac4f
--- /dev/null
+++ b/lib/compiler/test/beam_expect_SUITE.erl
@@ -0,0 +1,67 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2011. All Rights Reserved.
+%%
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(beam_expect_SUITE).
+
+-export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1,
+	 init_per_group/2,end_per_group/2,
+	 coverage/1]).
+
+suite() -> [{ct_hooks,[ts_install_cth]}].
+
+all() ->
+    [coverage].
+
+groups() ->
+    [].
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_GroupName, Config) ->
+    Config.
+
+end_per_group(_GroupName, Config) ->
+    Config.
+
+coverage(_) ->
+    File = {file,"fake.erl"},
+    ok = fc(a),
+    {'EXIT',{function_clause,
+	     [{?MODULE,fc,[[x]],[File,{line,2}]}|_]}} =
+	(catch fc([x])),
+    {'EXIT',{function_clause,
+	     [{?MODULE,fc,[y],[File,{line,2}]}|_]}} =
+	(catch fc(y)),
+    {'EXIT',{function_clause,
+	     [{?MODULE,fc,[[a,b,c]],[File,{line,6}]}|_]}} =
+	(catch fc([a,b,c])),
+
+    {'EXIT',{undef,[{erlang,error,[a,b,c],_}|_]}} =
+	(catch erlang:error(a, b, c)),
+    ok.
+
+-file("fake.erl", 1).
+fc(a) ->	                                %Line 2
+    ok;						%Line 3
+fc(L) when length(L) > 2 ->			%Line 4
+    %% Not the same as a "real" function_clause error.
+    error(function_clause, [L]).		%Line 6
diff --git a/lib/compiler/test/misc_SUITE.erl b/lib/compiler/test/misc_SUITE.erl
index 9b414cade6..5e13a93c52 100644
--- a/lib/compiler/test/misc_SUITE.erl
+++ b/lib/compiler/test/misc_SUITE.erl
@@ -190,6 +190,15 @@ silly_coverage(Config) when is_list(Config) ->
 		     {label,2}|non_proper_list]}],99},
     ?line expect_error(fun() -> beam_block:module(BlockInput, []) end),
 
+    %% beam_except
+    ExceptInput = {?MODULE,[{foo,0}],[],
+		   [{function,foo,0,2,
+		     [{label,1},
+		      {line,loc},
+		      {func_info,{atom,?MODULE},{atom,foo},0},
+		      {label,2}|non_proper_list]}],99},
+    expect_error(fun() -> beam_except:module(ExceptInput, []) end),
+
     %% beam_bool
     BoolInput = {?MODULE,[{foo,0}],[],
 		  [{function,foo,0,2,
@@ -253,8 +262,15 @@ expect_error(Fun) ->
 	    io:format("~p", [Any]),
 	    ?t:fail(call_was_supposed_to_fail)
     catch
-	_:_ ->
-	    io:format("~p\n", [erlang:get_stacktrace()])
+	Class:Reason ->
+	    Stk = erlang:get_stacktrace(),
+	    io:format("~p:~p\n~p\n", [Class,Reason,Stk]),
+	    case {Class,Reason} of
+		{error,undef} ->
+		    ?t:fail(not_supposed_to_fail_with_undef);
+		{_,_} ->
+		    ok
+	    end
     end.
 
 confused_literals(Config) when is_list(Config) ->