Add support for emitting external and .bss symbols.

llvm-svn: 22358

module to the ELF file.  Test it by adding support for emitting common
symbols.  This allows us to compile this:

%X = weak global int 0
%Y = weak global int 0
%Z = weak global int 0

to an elf file that 'readelf's this:

Symbol table '.symtab' contains 4 entries:
   Num:    Value  Size Type    Bind   Vis      Ndx Name
     0: 00000000     0 NOTYPE  LOCAL  DEFAULT  UND
     1: 00000004     4 OBJECT  GLOBAL DEFAULT  COM X
     2: 00000004     4 OBJECT  GLOBAL DEFAULT  COM Y
     3: 00000004     4 OBJECT  GLOBAL DEFAULT  COM Z

llvm-svn: 22343

1. Pass Value*'s into lowering methods so that the proper pointers can be
   added to load/stores from the valist
2. Intrinsics that return void should only return a token chain, not a token
   chain/retval pair.
3. Rename LowerVAArgNext -> LowerVAArg, because VANext is long gone.

llvm-svn: 22338

1: Legalize operand in UINT_TO_FP expanision

2: SRA x, const i8 was not promoting the constant to shift amount type.
llvm-svn: 22337

and legalizing the extload.  Strange.  Should fix most alpha regressions.

llvm-svn: 22329

llvm-svn: 22320

llvm-svn: 22319

llvm-svn: 22315

tracking the instructions causing loads and stores provides more information than just the pointer being loaded or stored

llvm-svn: 22311

handling it in the 64 bit case.  The two code paths should probably be merged.

llvm-svn: 22302

For now, the elf writer is only capable of emitting an empty elf file, with
a section table and a section table string table.  This will be enhanced
in the future :)

llvm-svn: 22291

See last commit for LangRef, this implements it on all targets.

llvm-svn: 22273

llvm-svn: 22254

integer types.  Add a couple checks to not perform these kinds of transform
on floating point values.

llvm-svn: 22228

llvm-svn: 22053

long %bar(long %X) {
  %Y = mul long %X, 4294967297
  ret long %Y
}

to this:

l1_bar:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EDX, %EAX
        add %EDX, DWORD PTR [%ESP + 8]
        ret

instead of:

l1_bar:
        mov %ECX, DWORD PTR [%ESP + 4]
        mov %EDX, 1
        mov %EAX, %ECX
        mul %EDX
        add %EDX, %ECX
        add %EDX, DWORD PTR [%ESP + 8]
        mov %EAX, %ECX
        ret

llvm-svn: 22044

terminator instructions before the 'ret' in case the target has a
multi-instruction return sequence.

llvm-svn: 22041

llvm-svn: 22026

llvm-svn: 22020

codepath

llvm-svn: 22019

llvm-svn: 22018

llvm-svn: 22016

llvm-svn: 22015

special case hacks.

llvm-svn: 22014

llvm-svn: 22011

llvm-svn: 22010

llvm-svn: 22009

llvm-svn: 22004

llvm-svn: 22002

llvm-svn: 22001

llvm-svn: 21993

llvm-svn: 21992

llvm-svn: 21982

llvm-svn: 21958

llvm-svn: 21957

llvm-svn: 21931

llvm-svn: 21930

llvm-svn: 21927

llvm-svn: 21923

I can actually remember which one is which now!

llvm-svn: 21922