[build] Separate _bin/shwrap/mycpp_main and _bin/shwrap/mycpp_main_so…

…uffle

Now we can build mos things without a C++ 17 compiler, which Souffle
requires.

I introduced a new wrapper _bin/shwrap/mycpp_main_souffle, and it
depends on:

- _bin/shwrap/mycpp_main
- _bin/datalog/dataflow - the binary derived from a datalog program

bin/NINJA_subgraph.py

@@ -80,14 +80,15 @@ def NinjaGraph(ru):
                 ('translator', translator),
                 ('preamble', 'cpp/preamble.h'),
             ]
-            if translator == 'mycpp-souffle':
-                variables.append(
-                    ('extra_mycpp_opts', '--minimize-stack-roots'))
+            if translator == 'mycpp':
+                shwrap_path = '_bin/shwrap/mycpp_main'
+            else:
+                shwrap_path = '_bin/shwrap/mycpp_main_souffle'
 
             n.build(outputs,
                     'gen-oils-for-unix',
                     deps,
-                    implicit=['_bin/shwrap/mycpp_main', RULES_PY],
+                    implicit=[shwrap_path, RULES_PY],
                     variables=variables)
 
             if main_name == 'oils_for_unix':

build/dynamic-deps.sh

@@ -196,9 +196,6 @@ write-mycpp() {
     | mysort \
     | tee $deps
 
-  # EXTRA FILE
-  echo '_bin/datalog/dataflow' >> $deps
-
   echo
   echo $dir/*
 }

build/ninja-rules-py.sh

@@ -18,6 +18,11 @@ source build/dev-shell.sh  # python2 in $PATH
 #source devtools/types.sh  # typecheck-files
 source $REPO_ROOT/test/tsv-lib.sh  # time-tsv
 
+die() {
+  echo "$@" >& 2
+  exit 1
+}
+
 example-main-wrapper() {
   ### Used by mycpp/examples
 
@@ -133,13 +138,13 @@ print-wrap-cc() {
 
    # main() function
    case $translator in
-     mycpp)
+     mycpp_main|mycpp_main_souffle)
        example-main-wrapper $main_module
        ;;
-     yaks)
+     yaks_main)
        main-wrapper $main_module
        ;;
-     pea)
+     pea_main)
        main-wrapper $main_module
        #echo '#include <stdio.h>'
        #echo 'int main() { printf("stub\n"); return 1; }'
@@ -303,6 +308,17 @@ exit $status
 EOF
 }
 
+shwrap-mycpp-souffle() {
+  cat <<'EOF'
+MYPYPATH=$1    # e.g. $REPO_ROOT/mycpp
+out=$2
+shift 2
+
+# Add an extra flag, and also depends on _bin/datalog
+exec _bin/shwrap/mycpp_main $MYPYPATH $out --minimize-stack-roots "$@"
+EOF
+}
+
 shwrap-pea() {
   ### Part of shell template for pea executable
 
@@ -353,6 +369,9 @@ EOF
     mycpp)
       shwrap-mycpp
       ;;
+    mycpp-souffle)
+      shwrap-mycpp-souffle
+      ;;
     pea)
       shwrap-pea
       ;;

build/ninja_lib.py

@@ -518,21 +518,28 @@ def asdl_library(self,
         )
 
     def py_binary(self, main_py, deps_base_dir='_build/NINJA', template='py'):
-        """
-        Wrapper for Python script with dynamically discovered deps
+        """Wrapper for Python script with dynamically discovered deps
+
+        Args:
+          template: py, mycpp, or pea
+
+        Example:
+          _bin/shwrap/mycpp_main wraps mycpp/mycpp_main.py
+            - using dependencies from prebuilt/ninja/mycpp.mycpp_main/deps.txt
+            - with the 'shwrap-mycpp' template defined in build/ninja-lib.sh
         """
         rel_path, _ = os.path.splitext(main_py)
-        py_module = rel_path.replace(
-            '/', '.')  # asdl/asdl_main.py -> asdl.asdl_main
+        # asdl/asdl_main.py -> asdl.asdl_main
+        py_module = rel_path.replace('/', '.')
 
         deps_path = os.path.join(deps_base_dir, py_module, 'deps.txt')
         with open(deps_path) as f:
             deps = [line.strip() for line in f]
 
         deps.remove(main_py)  # raises ValueError if it's not there
 
-        basename = os.path.basename(rel_path)
-        self.n.build('_bin/shwrap/%s' % basename,
+        shwrap_name = os.path.basename(rel_path)
+        self.n.build('_bin/shwrap/%s' % shwrap_name,
                      'write-shwrap', [main_py] + deps,
                      variables=[('template', template)])
         self.n.newline()

mycpp/NINJA_subgraph.py

@@ -14,10 +14,20 @@
 
 def DefineTargets(ru):
 
+    # Creates _bin/shwrap/mycpp_main
     ru.py_binary('mycpp/mycpp_main.py',
                  deps_base_dir='prebuilt/ninja',
                  template='mycpp')
 
+    # mycpp wrapper that depends on _bin/datalog/dataflow, a binary created
+    # from Souffle datalog!
+    ru.n.build(
+        '_bin/shwrap/mycpp_main_souffle',
+        'write-shwrap',
+        implicit=['_bin/shwrap/mycpp_main', '_bin/datalog/dataflow'],
+        variables=[('template', 'mycpp-souffle')],
+    )
+
     ru.cc_library(
         '//mycpp/runtime',
         # Could separate into //mycpp/runtime_{marksweep,bumpleak}
@@ -170,18 +180,21 @@ def TranslatorSubgraph(ru, translator, ex):
         # Note: build/ninja-rules-py.sh writes this 'shwrap'
         # It depends on MYPY_WEDGE and PY3_LIBS_WEDGE
         translator_wrapper = '_bin/shwrap/pea_main'
-        base_translator = 'pea'
         translate_rule = 'translate-pea'
-    else:
+    elif translator == 'mycpp':
         translate_rule = 'translate-mycpp'
-        base_translator = 'mycpp'
         translator_wrapper = '_bin/shwrap/mycpp_main'
+    elif translator == 'mycpp-souffle':
+        translate_rule = 'translate-mycpp-souffle'
+        translator_wrapper = '_bin/shwrap/mycpp_main_souffle'
+    else:
+        raise AssertionError('translator = %r' % translator)
 
     translator_vars = [
         ('mypypath', '$NINJA_REPO_ROOT/mycpp:$NINJA_REPO_ROOT/pyext'),
     ]
-    if translator == 'mycpp-souffle':
-        translator_vars.append(('extra_mycpp_opts', '--minimize-stack-roots'))
+    #if translator == 'mycpp-souffle':
+    #    translator_vars.append(('extra_mycpp_opts', '--minimize-stack-roots'))
 
     n.build(
         raw,
@@ -198,12 +211,17 @@ def TranslatorSubgraph(ru, translator, ex):
     main_cc_src = '_gen/mycpp/examples/%s.%s.cc' % (ex, translator)
 
     # Make a translation unit
-    n.build(main_cc_src,
-            'wrap-cc',
-            raw,
-            implicit=[RULES_PY],
-            variables=[('name', ex), ('preamble_path', preamble_path),
-                       ('translator', base_translator)])
+    n.build(
+        main_cc_src,
+        'wrap-cc',
+        raw,
+        implicit=[RULES_PY],
+        variables=[
+            ('name', ex),
+            ('preamble_path', preamble_path),
+            # translator is used to determine wrap-cc
+            ('translator', os.path.basename(translator_wrapper))
+        ])
 
     n.newline()
 
@@ -260,10 +278,14 @@ def NinjaGraph(ru):
     n.newline()
 
     # mycpp and pea have the same interface
-    n.rule(
-        'translate-mycpp',
-        command='_bin/shwrap/mycpp_main $mypypath $out $in $extra_mycpp_opts',
-        description='mycpp $mypypath $out $in')
+    n.rule('translate-mycpp',
+           command='_bin/shwrap/mycpp_main $mypypath $out $in',
+           description='mycpp $mypypath $out $in')
+    n.newline()
+
+    n.rule('translate-mycpp-souffle',
+           command='_bin/shwrap/mycpp_main_souffle $mypypath $out $in',
+           description='mycpp-souffle $mypypath $out $in')
     n.newline()
 
     n.rule('translate-pea',

prebuilt/ninja/mycpp.mycpp_main/deps.txt

@@ -10,4 +10,3 @@ mycpp/translate.py
 mycpp/util.py
 mycpp/virtual_pass.py
 mycpp/visitor.py
-_bin/datalog/dataflow

yaks/NINJA_subgraph.py

@@ -35,7 +35,7 @@ def NinjaGraph(ru):
             deps,
             implicit=['_bin/shwrap/mycpp_main', RULES_PY],
             variables=[('out_prefix', prefix), ('main_name', main_name),
-                       ('translator', 'yaks'),
+                       ('translator', 'yaks_main'),
                        ('preamble', 'yaks/preamble.h')])
 
     ru.cc_binary(
@@ -82,7 +82,7 @@ def NinjaGraph(ru):
             'wrap-cc', [raw_cc],
             implicit=[RULES_PY],
             variables=[('name', 'hello'), ('preamble_path', '""'),
-                       ('translator', 'yaks')])
+                       ('translator', 'yaks_main')])
     n.newline()
 
     ru.cc_binary(