compile: Add the {eprof,Pass} option for easy eprof running

To run eprof for a compiler pass:

  erlc +'{eprof,beam_asm}' file.erl

The name of the compiler pass is the name as printed when
'time' option is used. It is usually, but not always, the module
name for the compiler pass.

2 files changed, 26 insertions, 5 deletions

diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index f4ef6fcebf..0b021073db 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -285,11 +285,20 @@ internal_comp(Passes, File, Suffix, St0) ->
     St1 = St0#compile{filename=File, dir=Dir, base=Base,
 		      ifile=erlfile(Dir, Base, Suffix),
 		      ofile=objfile(Base, St0)},
-    Run = case member(time, St1#compile.options) of
-	      true  ->
-		  io:format("Compiling ~tp\n", [File]),
-		  fun run_tc/2;
-	      false -> fun({_Name,Fun}, St) -> catch Fun(St) end
+    Opts = St1#compile.options,
+    Run0 = case member(time, Opts) of
+	       true  ->
+		   io:format("Compiling ~tp\n", [File]),
+		   fun run_tc/2;
+	       false -> fun({_Name,Fun}, St) -> catch Fun(St) end
+	   end,
+    Run = case keyfind(eprof, 1, Opts) of
+	      {eprof,EprofPass} ->
+		  fun(P, St) ->
+			  run_eprof(P, EprofPass, St)
+		  end;
+	      false ->
+		  Run0
 	  end,
     case fold_comp(Passes, Run, St1) of
 	{ok,St2} -> comp_ret_ok(St2);
@@ -331,6 +340,16 @@ run_tc({Name,Fun}, St) ->
 	      [Name,(After_c-Before_c) / 1000,Mem]),
     Val.
 
+run_eprof({Name,Fun}, Name, St) ->
+    io:format("~p: Running eprof\n", [Name]),
+    eprof:start_profiling([self()]),
+    Val = (catch Fun(St)),
+    eprof:stop_profiling(),
+    eprof:analyze(),
+    Val;
+run_eprof({_,Fun}, _, St) ->
+    catch Fun(St).
+
 comp_ret_ok(#compile{code=Code,warnings=Warn0,module=Mod,options=Opts}=St) ->
     case werror(St) of
         true ->
diff --git a/lib/compiler/test/compile_SUITE.erl b/lib/compiler/test/compile_SUITE.erl
index 1c96abe017..6d4fde662b 100644
--- a/lib/compiler/test/compile_SUITE.erl
+++ b/lib/compiler/test/compile_SUITE.erl
@@ -102,6 +102,8 @@ file_1(Config) when is_list(Config) ->
     ?line compile_and_verify(Simple, Target, [debug_info]),
     ?line {ok,simple} = compile:file(Simple, [no_line_info]), %Coverage
 
+    {ok,simple} = compile:file(Simple, [{eprof,beam_z}]), %Coverage
+
     ?line ok = file:set_cwd(Cwd),
     ?line true = exists(Target),
     ?line passed = run(Target, test, []),