void assert_fail (const char* a, const char* file, int line) { // Used (optionally) in ASSERT macro in src/c/h/runtime-base.h
//
//
// Print an assertion failure message.
fprintf (stderr, "%s: Fatal error: Assertion failure (%s) at \"%s:%d\"\n", mythryl_program_name__global, a, file, line);
fflush (stderr);
pth__shut_down ();
print_stats_and_exit( 2 );
}
void die (char *fmt, ...) {
// ===
//
// Print an error message and then exit.
va_list ap;
va_start (ap, fmt);
fprintf (stderr, "%s: Fatal error: ", mythryl_program_name__global);
vfprintf (stderr, fmt, ap);
fprintf (stderr, "\n");
va_end(ap);
fflush(stderr);
// Release any platform-specific multicore-support
// resources such as kernel locks or mmapped segments:
//
pth__shut_down (); // pth__shut_down defined in src/c/hostthread/hostthread-on-posix-threads.c
print_stats_and_exit( 1 );
}
static void load_compiled_file__may_heapclean (
// =================================
//
Task* task,
char* filename,
Roots* extra_roots
){
///////////////////////////////////////////////////////
// Loading an compiledfile is a five-step process:
//
// 1. Read the header, which holds various
// numbers we need such as the number of
// code segments in the compiledfile.
//
// 2. Locate all the values imported by this
// compiledfile from the export lists of
// previously loaded compiled_files.
// For subsequent ease of access, we
// construct an 'import record' (a vector)
// holding all these values packed
// consecutively.
//
///////////////////////////////////////////////////////
FILE* file;
int i;
int bytes_of_code_remaining;
int bytes_of_exports = 0;
Compiledfile_Header header;
Picklehash export_picklehash;
Int1 segment_bytesize;
Int1 entrypoint_offset_in_bytes;
size_t archive_offset;
char* compiledfile_filename = filename;
// If 'filename' is a "library@offset:compiledfile" triple,
// parse it into its three parts:
//
{ char* at_ptr
=
strchr (filename, '@');
if (!at_ptr) {
archive_offset = 0; // We're loading a bare .compiled, not one packed within a library archive.
} else {
char* colon_ptr = strchr (at_ptr + 1, ':');
if (colon_ptr) {
*colon_ptr = '\0';
compiledfile_filename = colon_ptr + 1;
}
archive_offset = strtoul (at_ptr + 1, NULL, 0); // XXX SUCKO FIXME Needs more sanity checking.
*at_ptr = '\0';
}
}
// Log all files loaded, for diagnostic/information purposes:
//
if (!archive_offset) {
//
fprintf (
log_fd ? log_fd : stderr,
" load-compiledfiles.c: Loading object file %s\n",
filename
);
} else {
fprintf (
log_fd ? log_fd : stderr,
" load-compiledfiles.c: Loading offset %8d in lib %s \tnamely object file %s\n",
archive_offset,
filename,
compiledfile_filename
);
}
// Open the file:
//
file = open_file( filename, TRUE ); if (!file) print_stats_and_exit( 1 );
// If an offset is given (which is to say, if we are loading
// an compiledfile packed within a library archive) then
// then seek to the beginning of the section that contains
// the image of our compiledfile:
//
if (archive_offset) {
//
if (fseek (file, archive_offset, SEEK_SET) == -1) {
//
die ("Cannot seek on archive file \"%s@%ul\": %s", filename, (unsigned long) archive_offset, strerror(errno) );
}
}
// Get the header:
//
read_n_bytes_from_file( file, &header, sizeof(Compiledfile_Header), filename );
// The integers in the header are kept in big-endian byte
// order, so convert them if we're on a little-endian box:
//
header.number_of_imported_picklehashes = BIGENDIAN_TO_HOST( header.number_of_imported_picklehashes );
header.number_of_exported_picklehashes = BIGENDIAN_TO_HOST( header.number_of_exported_picklehashes );
header.bytes_of_import_tree = BIGENDIAN_TO_HOST( header.bytes_of_import_tree );
header.bytes_of_dependency_info = BIGENDIAN_TO_HOST( header.bytes_of_dependency_info );
header.bytes_of_inlinable_code = BIGENDIAN_TO_HOST( header.bytes_of_inlinable_code );
header.reserved = BIGENDIAN_TO_HOST( header.reserved );
header.pad = BIGENDIAN_TO_HOST( header.pad );
header.bytes_of_compiled_code = BIGENDIAN_TO_HOST( header.bytes_of_compiled_code );
header.bytes_of_symbolmapstack = BIGENDIAN_TO_HOST( header.bytes_of_symbolmapstack );
// XXX SUCKO FIXME These days 99% of the market is little-endian,
// so should either change to always little-endian, or else
// (better) always use host system's native byte ordering.
// Ideally we should be able to just mmap the .compiledfile into
// memory and be ready to go, with no bit-fiddling needed at all.
// Read the 'import tree' and locate all the thus-specified
// needed values located in the export tree of previously-
// loaded compiled_files:
//
int imports_record_slot_count
=
header.number_of_imported_picklehashes + 1;
// Make sure we have enough free heap space to allocate
// our 'import record' vector of imported values:
//
if (need_to_call_heapcleaner (task, REC_BYTESIZE(imports_record_slot_count))) {
//
call_heapcleaner_with_extra_roots (task, 0, extra_roots );
}
// Write the header for our 'import record', which will be
// a Mythryl record with 'imports_record_slot_count' slots:
//
set_slot_in_nascent_heapchunk (task, 0, MAKE_TAGWORD(imports_record_slot_count, PAIRS_AND_RECORDS_BTAG));
// Locate all the required import values and
// save them in our nascent on-heap 'import record':
//
{ int next_imports_record_slot_to_fill = 1;
// Over all previously loaded .compiled files
// from which we import values:
//
while (next_imports_record_slot_to_fill < imports_record_slot_count) {
//
Picklehash picklehash_naming_previously_loaded_compiled_file;
read_n_bytes_from_file( file, &picklehash_naming_previously_loaded_compiled_file, sizeof(Picklehash), filename );
// Locate all needed imports exported by that
// particular pre-loaded compiledfile:
//
next_imports_record_slot_to_fill
=
fetch_imports (
task,
file,
filename,
next_imports_record_slot_to_fill,
picklehash_to_exports_tree( &picklehash_naming_previously_loaded_compiled_file )
);
}
}
// Put a dummy valid value (NIL) in the last slot,
// just so the cleaner won't go bananas if it
// looks at that slot:
//
set_slot_in_nascent_heapchunk( task, imports_record_slot_count, HEAP_NIL );
// Complete the above by actually allocating
// the 'import record' on the Mythryl heap:
//
Val import_record = commit_nascent_heapchunk( task, imports_record_slot_count ); // Contains all the values we import from other compiled_files.
Roots roots1 = { &import_record, extra_roots };
// Get the export picklehash for this compiledfile.
// This is the name by which other compiled_files will
// refer to us in their turn as they are loaded.
//
// Some compiled_files may not have such a name, in
// which case they have no directly visible exported
// values. (This typically means that they are a
// plug-in which installs pointers to itself in some
// other module's datastructures, as a side-effect
// during loading.)
//
if (header.number_of_exported_picklehashes == 1) {
bytes_of_exports = sizeof( Picklehash );
read_n_bytes_from_file( file, &export_picklehash, bytes_of_exports, filename );
} else if (header.number_of_exported_picklehashes != 0) {
die ("Number of exported picklehashes is %d (should be 0 or 1)",
(int)header.number_of_exported_picklehashes
);
}
// Seek to the first "code segment" within our compiledfile image.
// This contains bytecoded instructions interpretable by
// make-package-literals-via-bytecode-interpreter.c which construct all the needed constant
// lists etc for this compiledfile. (If we stored them as actual
// lists, we'd have to do relocations on all the pointers in
// those structures at this point. The bytecode solution seems
// simpler.)
{
// XXX BUGGO FIXME A 'long' is 32 bits on 32-bit Linux,
// but files longer than 2GB (signed long!) are often
// supported. We probably should use fseeko in those
// cases and then
// #define _FILE_OFFSET_BITS 64
// so as to support large (well, *huge* :) library files.
// See the manpage for details.
// This probably won't be a frequent problem in practice
// for a few years yet, and by then we'll probably be
// running 64-bit Linux anyhow, so not a high priority.
//
long file_offset = archive_offset
+ sizeof(Compiledfile_Header)
+ header.bytes_of_import_tree
+ bytes_of_exports
+ header.bytes_of_dependency_info
+ header.bytes_of_inlinable_code
+ header.reserved
+ header.pad;
if (fseek(file, file_offset, SEEK_SET) == -1) {
//
die ("cannot seek on .compiled file \"%s\": %s", filename, strerror(errno) );
}
}
////////////////////////////////////////////////////////////////
// In principle, a .compiled file can contain any number of
// code segments, so we track the number of bytes of code
// left to process: When it hits zero, we've done all
// the code segments.
//
// In practice, we currently always have exactly two
// code segments, the first of which contains the byte-
// coded logic constructing our literals (constants
// -- see src/c/heapcleaner/make-package-literals-via-bytecode-interpreter.c)
// and the second of which contains all our compiled
// native code for the compiledfile, including that
// which constructs our tree of exported (directly externally
// visible) values.
////////////////////////////////////////////////////////////////
bytes_of_code_remaining
=
header.bytes_of_compiled_code;
// Read the size and the dummy entry point for the
// first code segment (literal-constructing bytecodes).
// The entrypoint offset of this first segment is always
// zero, which is why we ignore it here:
//
read_n_bytes_from_file( file, &segment_bytesize, sizeof(Int1), filename );
//
segment_bytesize = BIGENDIAN_TO_HOST( segment_bytesize );
//
read_n_bytes_from_file( file, &entrypoint_offset_in_bytes, sizeof(Int1), filename );
//
// entrypoint_offset_in_bytes = BIGENDIAN_TO_HOST( entrypoint_offset_in_bytes );
bytes_of_code_remaining -= segment_bytesize + 2 * sizeof(Int1);
//
if (bytes_of_code_remaining < 0) {
//
die ("format error (data size mismatch) in .compiled file \"%s\"", filename);
}
Val mythryl_result = HEAP_VOID;
if (segment_bytesize > 0) {
//
Unt8* data_chunk = MALLOC_VEC( Unt8, segment_bytesize );
read_n_bytes_from_file( file, data_chunk, segment_bytesize, filename );
mythryl_result = make_package_literals_via_bytecode_interpreter__may_heapclean (task, data_chunk, segment_bytesize, &roots1);
FREE(data_chunk);
}
// Do a functional update of the last element of the import_record:
//
for (i = 0; i < imports_record_slot_count; i++) {
//
set_slot_in_nascent_heapchunk(task, i, PTR_CAST(Val*, import_record)[i-1]); // <============ last use of import_record
}
set_slot_in_nascent_heapchunk( task, imports_record_slot_count, mythryl_result );
mythryl_result = commit_nascent_heapchunk( task, imports_record_slot_count );
Roots roots2 = { &mythryl_result, extra_roots }; // 'extra_roots' not '&roots1' because import_record is dead here.
// Do a garbage collection, if necessary:
//
if (need_to_call_heapcleaner( task, PICKLEHASH_BYTES + REC_BYTESIZE(5)) ) {
//
call_heapcleaner_with_extra_roots (task, 0, &roots2 );
}
while (bytes_of_code_remaining > 0) { // In practice, we always execute this loop exactly once.
//
// Read the size and entry point for this code chunk:
read_n_bytes_from_file( file, &segment_bytesize, sizeof(Int1), filename );
segment_bytesize = BIGENDIAN_TO_HOST( segment_bytesize );
read_n_bytes_from_file( file, &entrypoint_offset_in_bytes, sizeof(Int1), filename );
entrypoint_offset_in_bytes = BIGENDIAN_TO_HOST( entrypoint_offset_in_bytes );
// How much more?
//
bytes_of_code_remaining -= segment_bytesize + 2 * sizeof(Int1);
//
if (bytes_of_code_remaining < 0) die ("format error (code size mismatch) in .compiled file \"%s\"", filename);
// Allocate heap space and read code chunk:
//
Val code_chunk = allocate_nonempty_code_chunk (task, segment_bytesize);
//
read_n_bytes_from_file( file, PTR_CAST(char*, code_chunk), segment_bytesize, filename );
// Flush the instruction cache, so CPU will see
// our newly loaded code. (To gain speed, and
// simplify the hardware design, most modern CPUs
// assume that code is never modified on the fly,
// or at least not without manually flushing the
// instruction cache this way.)
//
flush_instruction_cache (PTR_CAST(char*, code_chunk), segment_bytesize);
// Create closure, taking entry point into account:
//
{ Val closure = make_one_slot_record( task, PTR_CAST( Val, PTR_CAST (char*, code_chunk) + entrypoint_offset_in_bytes) );
// Apply the closure to the import picklehash vector.
//
// This actually executes all the top-level code for
// the compile unit, which is to say that if the
// source for our compiledfile looked something like
//
// package my_pkg {
// my _ = file::print "Hello, world!\n";
// };
//
// then when we do the following 'apply' call, you'd see
//
// Hello, world!
//
// printed on the standard output.
//
// In addition, invisible compiler-generated code
// constructs and returns the tree of exports from
// our compiledfile.
//
save_c_state (task, extra_roots); // We do NOT want mythryl_result on the extra_roots list here.
mythryl_result = run_mythryl_function__may_heapclean (task, closure, mythryl_result, TRUE, NULL); // run_mythryl_function__may_heapclean def in src/c/main/run-mythryl-code-and-runtime-eventloop.c
restore_c_state (task, extra_roots);
}
if (need_to_call_heapcleaner (task, PICKLEHASH_BYTES+REC_BYTESIZE(5))) {
//
call_heapcleaner_with_extra_roots (task, 0, &roots2 );
}
}
// Publish this compiled_file's exported-values tree
// for the benefit of compiled_files loaded later:
//
if (bytes_of_exports) {
//
register_compiled_file_exports__may_heapclean (
task,
&export_picklehash, // key -- the 16-byte picklehash naming this compiledfile.
mythryl_result, // val -- the tree of exported Mythryl values.
extra_roots
);
}
fclose( file );
} // load_compiled_file__may_heapclean
