On Wed, 25 Jun 2003 10:18:17 +0100
Alastair Reid
| It is sad that the usage of libraries containing polymorphic code | [...] | seems to imply runtime overheads, by preventing specialisation.
I agree that it is sad. The only way around it is to ship libraries with *all* their source code (perhaps hidden in the interface file). That could be done, but it'd be Real Work
One way of tackling it would be to change ghc so that compilation doesn't produce .o files containing machine code but, rather, files containing a concise encoding of STG code. One possible concise encoding would be as bytecodes. (With just a little care over their design, you can easily uncompile bytecodes to recover the original code so we're not losing any information.)
Something similar was proposed by the gcc folk at their recent conference. The idea is that when you gcc -O4 your .c files, you get .o files containing an intermediate typed SSA form. Upon linking the program, gcc invokes a 'smart linker' which runs another pass on the whole program. This allows for all kinds of cross-module inlining, specialisation etc. http://www.linux.org.uk/~ajh/gcc/gccsummit-2003-proceedings.pdf pg 121, Architecture for a Next-Generation GCC Duncan