Perl 4's special variable $* controls multi-line matching; it's been
  deprecated from Perl 5's inception, and is finally removed in Perl
  versions 5.9 (soon to be 5.10).

  Since GHC depends on Perl 5.6+ anyway, this patch introduces an
  equivalent effect to $* without using that special variable, by
  hooking into Perl's regex parsing process to add the /m flag.

Save/restore two more registers in StgCRun().  The extra 
registers are used by ffi009.hs, when compiling with gcc 4.1.2.

Gcc 4 is doing more clever optimizations than earlier gccs. 
These changes let ghc compile and run on ia64 with gcc 4.0.3.

Register stack frames are enlarged so that all functions use the 
same size stack frame.
The code to mangle tail calls has been cleaned up and made more 
general.
Additional floating-point and special-purpose registers used by 
GCC are saved upon entering the STG runtime.
More general handling of NOP instructions.
Handling of functions with multiple epilogues or no epilogue.

Info tables, like everything else in the text section, MUST NOT contain
pointers. A pointer is, by definition, position dependent and is therefore
fundamentally incompatible with generating position independent code.

Therefore, we have to store an offset from the info label to the string
instead of the pointer, just as we already did for other things referred
to by the info table (SRTs, large bitmaps, etc.)

From heatsink, in trac #1150.

This has the undesitrable effect that stg_gc_gen_hp in the RTS was
caught as an HPC symbol and put in the data segment.

Patch by Ferris McCormick <fmccor@gentoo.org>
This patch has been tested with GHC-6.4.2 where it fixes a
huge number of testsuite failures (down from 406 to 17)

Basic -fvia-C code generation is there, not much testing.

This large checkin is the new ghc version of Haskell
Program Coverage, an expression-level coverage tool for Haskell.

Parts:

 - Hpc.[ch] - small runtime support for Hpc; reading/writing *.tix files.
 - Coverage.lhs - Annotates the HsSyn with coverage tickboxes.
  - New Note's in Core,
      - TickBox      -- ticked on entry to sub-expression
      - BinaryTickBox  -- ticked on exit to sub-expression, depending
	       	     -- on the boolean result.

  - New Stg level TickBox (no BinaryTickBoxes, though) 

You can run the coverage tool with -fhpc at compile time. 
Main must be compiled with -fhpc. 
				      

Most of the other users of the fptools build system have migrated to
Cabal, and with the move to darcs we can now flatten the source tree
without losing history, so here goes.

The main change is that the ghc/ subdir is gone, and most of what it
contained is now at the top level.  The build system now makes no
pretense at being multi-project, it is just the GHC build system.

No doubt this will break many things, and there will be a period of
instability while we fix the dependencies.  A straightforward build
should work, but I haven't yet fixed binary/source distributions.
Changes to the Building Guide will follow, too.

Linux/PPC64: remove some dead code that accidentally slipped in.

MERGE TO STABLE

Discard various ways in which gcc zeroes stack slots in the prologue.
So far in my investigations these have always been unnecessary, they
appear to be the result of missed optimisations by gcc, so cross
fingers and discard them.  New variants have just shown up because I
started compiling the RTS with -optc-O2.

clean up more junk generated by gcc

x86_64: catch and fix one kind of crappy code generated by gcc

	    #    movq -4(%rbp), %rax
	    #    jmp  *%rax

==>

	    #    jmp  *-4(%rbp)

Update for Sparc/Solaris from Christian Meader.  This might fix GHCi
on Sparc.

Darwin/x86:
Instead of aligning all literals at 16 bytes, reuse the hack from x86-64.

Darwin/x86:
Fix two causes for crashes:
*) align literals to 16 bytes, because Apple's GCC likes to use
   SSE instructions which require this alignment.
*) In print_doctored, recognize global jumps that masquerade as
   local jumps by going via Lfoo$stub or Lfoo$non_lazy_ptr.

Registerised support for Darwin/x86, both NCG and mangled.

*) -fPIC doesn't work yet with -fvia-C.
*) Apple officially requires the stack to be 16-byte-aligned,
   GHC ignores this for now.

Allow calls to __alloca in the prologue on mingw32 (previously only
allowed for cygwin32, I guess it hasn't happened for a while).

Check for reserved stack space blown.

Mangler support for GNU/Hurd.

From: Thomas Schwinge

More Mac OS X Tiger / GCC 4.0 fixes.

MERGE TO STABLE

Mac OS X (Tiger): Fix the Mangler for (Apple's version of) GCC 4.0

MERGE TO STABLE

HACK HACK HACK on x86_64

we need 16-byte aligned constants on this platform sometimes.  Don't
just 16-byte align everything, but try to detect 16-byte constants and
align just those.

All the codegen tests now go through on registerised x86_64, I'm
building a stage2 GHC now.

x86_64: the assembler doesn't like generating 8-byte relative
relocations between text and rodata symbols.  Hack around this by
putting SRTs in the text segment for now.

Sparc: allow whitespace before .section directive.  Should fix
linking problems on sparc/solaris.

Fix previous commit. Got distracted, thought I had already tested.

Fix Mac OS X-specific breakage introduced by rev. 1.67 of ghc/includes/Stg.h.
Adding the used attribute to static functions caused gcc to emit
Apple-specific .no_dead_strip directives, which messed things up.