Change the way module initialisation is done (#3252, #4417) Previously the code generator generated small code fragments labelled with __stginit_M for each module M, and these performed whatever initialisation was necessary for that module and recursively invoked the initialisation functions for imported modules. This appraoch had drawbacks: - FFI users had to call hs_add_root() to ensure the correct initialisation routines were called. This is a non-standard, and ugly, API. - unless we were using -split-objs, the __stginit dependencies would entail linking the whole transitive closure of modules imported, whether they were actually used or not. In an extreme case (#4387, #4417), a module from GHC might be imported for use in Template Haskell or an annotation, and that would force the whole of GHC to be needlessly linked into the final executable. So now instead we do our initialisation with C functions marked with __attribute__((constructor)), which are automatically invoked at program startup time (or DSO load-time). The C initialisers are emitted into the stub.c file. This means that every time we compile with -prof or -hpc, we now get a stub file, but thanks to #3687 that is now invisible to the user. There are some refactorings in the RTS (particularly for HPC) to handle the fact that initialisers now get run earlier than they did before. The __stginit symbols are still generated, and the hs_add_root() function still exists (but does nothing), for backwards compatibility.
Merge in new code generator branch. This changes the new code generator to make use of the Hoopl package for dataflow analysis. Hoopl is a new boot package, and is maintained in a separate upstream git repository (as usual, GHC has its own lagging darcs mirror in http://darcs.haskell.org/packages/hoopl). During this merge I squashed recent history into one patch. I tried to rebase, but the history had some internal conflicts of its own which made rebase extremely confusing, so I gave up. The history I squashed was: - Update new codegen to work with latest Hoopl - Add some notes on new code gen to cmm-notes - Enable Hoopl lag package. - Add SPJ note to cmm-notes - Improve GC calls on new code generator. Work in this branch was done by: - Milan Straka <fox@ucw.cz> - John Dias <dias@cs.tufts.edu> - David Terei <davidterei@gmail.com> Edward Z. Yang <ezyang@mit.edu> merged in further changes from GHC HEAD and fixed a few bugs.
* Refactor CLabel.RtsLabel to CLabel.CmmLabel The type of the CmmLabel ctor is now CmmLabel :: PackageId -> FastString -> CmmLabelInfo -> CLabel - When you construct a CmmLabel you have to explicitly say what package it is in. Many of these will just use rtsPackageId, but I've left it this way to remind people not to pretend labels are in the RTS package when they're not. - When parsing a Cmm file, labels that are not defined in the current file are assumed to be in the RTS package. Labels imported like import label are assumed to be in a generic "foreign" package, which is different from the current one. Labels imported like import "package-name" label are marked as coming from the named package. This last one is needed for the integer-gmp library as we want to refer to labels that are not in the same compilation unit, but are in the same non-rts package. This should help remove the nasty #ifdef __PIC__ stuff from integer-gmp/cbits/gmp-wrappers.cmm
Merge RtsLabelInfo.Rts* with RtsLabelInfo.Rts*FS
RTS tidyup sweep, first phase The first phase of this tidyup is focussed on the header files, and in particular making sure we are exposinng publicly exactly what we need to, and no more. - Rts.h now includes everything that the RTS exposes publicly, rather than a random subset of it. - Most of the public header files have moved into subdirectories, and many of them have been renamed. But clients should not need to include any of the other headers directly, just #include the main public headers: Rts.h, HsFFI.h, RtsAPI.h. - All the headers needed for via-C compilation have moved into the stg subdirectory, which is self-contained. Most of the headers for the rest of the RTS APIs have moved into the rts subdirectory. - I left MachDeps.h where it is, because it is so widely used in Haskell code. - I left a deprecated stub for RtsFlags.h in place. The flag structures are now exposed by Rts.h. - Various internal APIs are no longer exposed by public header files. - Various bits of dead code and declarations have been removed - More gcc warnings are turned on, and the RTS code is more warning-clean. - More source files #include "PosixSource.h", and hence only use standard POSIX (1003.1c-1995) interfaces. There is a lot more tidying up still to do, this is just the first pass. I also intend to standardise the names for external RTS APIs (e.g use the rts_ prefix consistently), and declare the internal APIs as hidden for shared libraries.
Remove unused imports
Fix warnings in CgProf
Merging in the new codegen branch This merge does not turn on the new codegen (which only compiles a select few programs at this point), but it does introduce some changes to the old code generator. The high bits: 1. The Rep Swamp patch is finally here. The highlight is that the representation of types at the machine level has changed. Consequently, this patch contains updates across several back ends. 2. The new Stg -> Cmm path is here, although it appears to have a fair number of bugs lurking. 3. Many improvements along the CmmCPSZ path, including: o stack layout o some code for infotables, half of which is right and half wrong o proc-point splitting
replace Cmm 'hint' with 'kind' C-- no longer has 'hints'; to guide parameter passing, it has 'kinds'. Renamed type constructor, data constructor, and record fields accordingly
(F)SLIT -> (f)sLit in CgProf
change CmmActual, CmmFormal to use a data CmmHinted rather than tuple (#1405) This allows the instance of UserOfLocalRegs to be within Haskell98, and IMHO makes the code a little cleaner generally. This is one small (though tedious) step towards making GHC's code more portable...
Move OPTIONS pragmas above comments Fixes building with -Werror (i.e. validate) and GHC < 6.6
Fix CodingStyle#Warnings URLs
Use OPTIONS rather than OPTIONS_GHC for pragmas Older GHCs can't parse OPTIONS_GHC. This also changes the URL referenced for the -w options from WorkingConventions#Warnings to CodingStyle#Warnings for the compiler modules.
Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modules
Pointer Tagging This patch implements pointer tagging as per our ICFP'07 paper "Faster laziness using dynamic pointer tagging". It improves performance by 10-15% for most workloads, including GHC itself. The original patches were by Alexey Rodriguez Yakushev <mrchebas@gmail.com>, with additions and improvements by me. I've re-recorded the development as a single patch. The basic idea is this: we use the low 2 bits of a pointer to a heap object (3 bits on a 64-bit architecture) to encode some information about the object pointed to. For a constructor, we encode the "tag" of the constructor (e.g. True vs. False), for a function closure its arity. This enables some decisions to be made without dereferencing the pointer, which speeds up some common operations. In particular it enables us to avoid costly indirect jumps in many cases. More information in the commentary: http://hackage.haskell.org/trac/ghc/wiki/Commentary/Rts/HaskellExecution/PointerTagging
Implemented and fixed bugs in CmmInfo handling
Added pointerhood to LocalReg This version should compile but is still incomplete as it introduces potential bugs at the places marked 'TODO FIXME NOW'. It is being recorded to help keep track of changes.
Module header tidyup, phase 1 This patch is a start on removing import lists and generally tidying up the top of each module. In addition to removing import lists: - Change DATA.IOREF -> Data.IORef etc. - Change List -> Data.List etc. - Remove $Id$ - Update copyrights - Re-order imports to put non-GHC imports last - Remove some unused and duplicate imports
Don't include the package name in a cost centre's module name This is mainly to restore the old behaviour, but also we shouldn't normally need the package name in a cost centre because only the "main" package normally has cost centres.