Add emcc option "--split <size>" to split javascript file.

Splits the resulting javascript file into pieces to ease debugging.
This option only works if Javascript is generated (target -o <name>.js).

Files with function declarations must be loaded before main file upon execution.

Without "-g" option:
Creates files with function declarations up to the given size with the suffix "_functions.partxxx.js" and a main file with the suffix ".js".

With "-g" option:
Recreates the directory structure of the C source files and stores function declarations in their respective C files with the suffix ".js". If such a file exceeds the given size, files with the suffix ".partxxx.js" are created. The main file resides in the base directory and has the suffix ".js".

1 files changed, 36 insertions, 2 deletions

diff --git a/emcc b/emcc
index 97bc2f68..1dc9b756 100755
--- a/emcc
+++ b/emcc
@@ -268,6 +268,27 @@ Options that are modified or new in %s include:
                               will not minify the code (closure does
                               that)
 
+  --split <size>           Splits the resulting javascript file into pieces
+                           to ease debugging. This option only works if
+                           Javascript is generated (target -o <name>.js).
+                           Files with function declarations must be loaded
+                           before main file upon execution.
+
+                           Without "-g" option:
+                              Creates files with function declarations up
+                              to the given size with the suffix
+                              "_functions.partxxx.js" and a main file with
+                              the suffix ".js".
+
+                           With "-g" option:
+                              Recreates the directory structure of the C
+                              source files and stores function declarations
+                              in their respective C files with the suffix
+                              ".js". If such a file exceeds the given size,
+                              files with the suffix ".partxxx.js" are created.
+                              The main file resides in the base directory and
+                              has the suffix ".js".
+
   --ignore-dynamic-linking Normally emcc will treat dynamic linking like
                            static linking, by linking in the code from
                            the dynamic library. This fails if the same
@@ -471,6 +492,7 @@ try:
   pre_js = ''
   post_js = ''
   minify_whitespace = None
+  split_js_file = None
   preload_files = []
   embed_files = []
   compression = None
@@ -527,6 +549,11 @@ try:
       minify_whitespace = int(newargs[i+1])
       newargs[i] = ''
       newargs[i+1] = ''
+    elif newargs[i].startswith('--split'):
+      check_bad_eq(newargs[i])
+      split_js_file = int(newargs[i+1])
+      newargs[i] = ''
+      newargs[i+1] = ''      
     elif newargs[i].startswith('--embed-file'):
       check_bad_eq(newargs[i])
       embed_files.append(newargs[i+1])
@@ -601,6 +628,9 @@ try:
       newargs[i+1] = ''
   newargs = [ arg for arg in newargs if arg is not '' ]
 
+  if split_js_file:
+      settings_changes.append("PRINT_SPLIT_FILE_MARKER=1")
+
   # Find input files
 
   input_files = []
@@ -1071,8 +1101,12 @@ try:
 
     html.close()
   else:
-    # copy final JS to output
-    shutil.move(final, target)
+    if split_js_file:
+        from tools.split import split_javascript_file
+        split_javascript_file(final, unsuffixed(target), split_js_file)
+    else:
+        # copy final JS to output
+        shutil.move(final, target)
 
 finally:
   if not TEMP_DIR: