Add an example program that utilizes multiple threads in the JIT to process
work. This was used by Evan Jones as the original test case for ensuring
that the ExecutionEngine was thread safe.

Original source by Evan Jones (adapted from other LLVM JIT examples) and
made LLVM style compliant by Reid Spencer.

llvm-svn: 22411

working before modifying the asm printer to use the subtarget info.

llvm-svn: 22408

llvm-svn: 22407

llvm-svn: 22405

This patch completes the changes for making lli thread-safe. Here's the list
of changes:
* The Support/ThreadSupport* files were removed and replaced with the
  MutexGuard.h file since all ThreadSupport* declared was a Mutex Guard.
  The implementation of MutexGuard.h is now based on sys::Mutex which hides
  its implementation and makes it unnecessary to have the -NoSupport.h and
  -PThreads.h versions of ThreadSupport.

* All places in ExecutionEngine that previously referred to "Mutex" now
  refer to sys::Mutex

* All places in ExecutionEngine that previously referred to "MutexLocker"
  now refer to MutexGuard (this is frivolous but I believe the technically
  correct name for such a class is "Guard" not a "Locker").

These changes passed all of llvm-test. All we need now are some test cases
that actually use multiple threads.

llvm-svn: 22404

Add a Mutex class for thread synchronization in a platform-independent way.
The current implementation only supports pthreads. Win32 use of Critical
Sections will be added later. The design permits other threading models to
be used if (and only if) pthreads is not available.

llvm-svn: 22403

* Add check for pthread.h
* Make sure -lpthread gets added to LIBS if its available

llvm-svn: 22402

Make sure that -lpthread gets added to LIBS variable which puts it at the
end of the tools' link commands, if libpthread.a is found.

Add a test for pthread.h so we can use #ifdef HAVE_PTHREAD_H

llvm-svn: 22401

llvm-svn: 22400

llvm-svn: 22399

llvm-svn: 22398

llvm-svn: 22397

llvm-svn: 22396

llvm-svn: 22395

llvm-svn: 22394

llvm-svn: 22393

to the constructor.

llvm-svn: 22392

llvm-svn: 22391

llvm-svn: 22390

Implement the X86 Subtarget.

This consolidates the checks for target triple, and setting options based
on target triple into one place.  This allows us to convert the asm printer
and isel over from being littered with "forDarwin", "forCygwin", etc. into
just having the appropriate flags for each subtarget feature controlling
the code for that feature.

This patch also implements indirect external and weak references in the
X86 pattern isel, for darwin.  Next up is to convert over the asm printers
to use this new interface.

llvm-svn: 22389

llvm-svn: 22388

Instead of emitting a JIT stub that looks like this:

internal void %l1_main_entry_2E_ce_wrapper(int) {
header:
        %resolver = call sbyte* %getPointerToNamedFunction( sbyte* getelementptr ([20 x sbyte]* %l1_main_entry_2E_ce_name, int 0, int 0) )           ; <sbyte*> [#uses=1]
        %resolverCast = cast sbyte* %resolver to void (int)*            ; <void (int)*> [#uses=1]
        call void %resolverCast( int %0 )
        ret void
}

Emit one that looks like this:

internal void %l1_main_entry_2E_ce_wrapper(int) {
Entry:
	%fpcache = load void (int)** %l1_main_entry_2E_ce.fpcache               ; <void (int)*> [#uses=2]
        %isNull = seteq void (int)* %fpcache, null              ; <bool> [#uses=1]
        br bool %isNull, label %lookupfp, label %usecache

usecache:               ; preds = %lookupfp, %Entry
        %fp = phi void (int)* [ %resolverCast, %lookupfp ], [ %fpcache, %Entry ]            ; <void (int)*> [#uses=1]
        call void %fp( int %0 )
        ret void

lookupfp:               ; preds = %Entry
        %resolver = call sbyte* %getPointerToNamedFunction( sbyte* getelementptr ([20 x sbyte]* %l1_main_entry_2E_ce_name, int 0, int 0) )           ; <sbyte*> [#uses=1]
        %resolverCast = cast sbyte* %resolver to void (int)*            ; <void (int)*> [#uses=2]
        store void (int)* %resolverCast, void (int)** %l1_main_entry_2E_ce.fpcache
        br label %usecache
}


This makes the JIT debugger *MUCH* faster on large programs, as
getPointerToNamedFunction takes time linear with the size of the program, and
before we would call it every time a function in the text module was called from
the safe module (ouch!).

llvm-svn: 22387

llvm-svn: 22386

llvm-svn: 22385

llvm-svn: 22384

#   define errno (*__errno_location ())

*shakes head

llvm-svn: 22383

llvm-svn: 22382

llvm-svn: 22381

llvm-svn: 22380

llvm-svn: 22379

allows objdump to know which function we are emitting to:

00000000 <foo>:     <----
   0:   b8 01 00 00 00          mov    $0x1,%eax
   5:   03 44 24 04             add    0x4(%esp,1),%eax
   9:   c3                      ret

... and allows .o files to be useful for linking :)

llvm-svn: 22378

llvm-svn: 22377

after itself.

llvm-svn: 22376

Add a *VERY INITIAL* machine code emitter class.  This is enough to take
this C function:
int foo(int X) { return X +1; }

and make objdump produce the following:

$ objdump -d t-llvm.o

t-llvm.o:     file format elf32-i386

Disassembly of section .text:

00000000 <.text>:
   0:   b8 01 00 00 00          mov    $0x1,%eax
   5:   03 44 24 04             add    0x4(%esp,1),%eax
   9:   c3                      ret


Anything using branches or refering to the constant pool or requiring
relocations will not work yet.

llvm-svn: 22375

llvm-svn: 22374

llvm-svn: 22373

llvm-svn: 22372

characters from them.

llvm-svn: 22371

llvm-svn: 22370

llvm-svn: 22369