On Wed, Jan 27, 2010 at 9:34 AM, Bert Freudenberg bert@freudenbergs.dewrote:
On 27.01.2010, at 09:28, Eliot Miranda wrote:
On Wed, Jan 27, 2010 at 7:26 AM, Bert Freudenberg bert@freudenbergs.dewrote:
On 27.01.2010, at 05:37, K. K. Subramaniam wrote:
On Tuesday 26 January 2010 11:09:26 pm Bert Freudenberg wrote:
Well, there is a source for this of course (in the VMMaker Squeak
package).
Generating the C code is a manual, interactive process and requires a running Squeak installation. Making that scriptable is possible, but so far nobody has done it AFAIK
That is because most of the builds so far have been one target (which is
also
the host). Batch builds are needed for multiple variants (e.g
debug/release)
or when cross-compiling (say to ARM targets).
Ian does batched cross-builds. But the source is still only generated once. All targets use the same generated sources.
Ditto. We changed to a single src tree for Mac OS, win32 & linux very recently. The VMMaker per platform strikes me as absurd. All Microsoft and Mac compilers I've ever used are happy with LF line endings. The only significant difference between the platforms is whether to use the struct for interpreter variables and with a little macrology the choice can be left up to the platform's makefiles. In the Teleplace VMs the structure declaration looks like:
/*** Variables ***/ #if SQ_USE_GLOBAL_STRUCT # define _iss /* define in-struct static as void */ struct foo { #else # define _iss static #endif _iss char * stackPointer; _iss sqInt primFailCode; _iss sqInt specialObjectsOop; _iss char * framePointer; _iss StackPage * stackPage; _iss sqInt nilObj;
...
_iss char * stackMemory; _iss sqInt theUnknownShort; #undef _iss #if SQ_USE_GLOBAL_STRUCT } fum; # define DECL_MAYBE_SQ_GLOBAL_STRUCT register struct foo * foo = &fum; # define DECL_MAYBE_VOLATILE_SQ_GLOBAL_STRUCT volatile register struct foo
- foo = &fum;
# define GIV(interpreterInstVar) (foo->interpreterInstVar) #else # define DECL_MAYBE_SQ_GLOBAL_STRUCT /* oh, no mr bill! */ # define DECL_MAYBE_VOLATILE_SQ_GLOBAL_STRUCT /* oh no, mr bill! */ # define GIV(interpreterInstVar) interpreterInstVar #endif #if SQ_USE_GLOBAL_STRUCT static struct foo * foo = &fum; #endif
and then a function that uses global variables looks like
EXPORT(sqInt) addGCRoot(sqInt *varLoc) { DECL_MAYBE_SQ_GLOBAL_STRUCT if (GIV(extraRootCount) >= ExtraRootSize) { return 0; } GIV(extraRoots)[GIV(extraRootCount) += 1] = varLoc; return 1; }
And for us whether to use the global struct or not on Mac OS depends on whether we're using the Intel compiler or gcc. The Intel compiler produces an interpreter (not a JIT) that is 10% faster if it uses the global struct, whereas gcc produces one that is slightly slower. So making the choice depend on platform is a mistake anyway. It depends on platform and compiler.
- Bert -
Sounds cool. I'd love to have the generated sources to be identical across platforms, plus have the plugin sources be the same for internal and external plugins. For each plugin I'd like to choose to build it internally or externally or not at all, without regenerating.
Yes, that's what we do. Basically plugins.int plugins.ext and sqNamedPrims.h are part of the platform's makefiles (although sqNamedPrims.h should be generated), and so one pushes out a superset of the plugins and decides in the platform makefiles which to include and which are internal or external. As soon as my Feb deliverable is done I'll put some energy into getting Cog released.
best Eliot
- Bert -