dragonegg self-host build.  I reverted 96640 in order to revert
96556 (96640 goes on top of 96556), but it also looks like with
both of them applied the breakage happens even earlier.  The
symptom of the 96556 miscompile is the following crash:

  llvm[3]: Compiling AlphaISelLowering.cpp for Release build
  cc1plus: /home/duncan/tmp/tmp/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4982: void llvm::SelectionDAG::ReplaceAllUsesWith(llvm::SDNode*, llvm::SDNode*, llvm::SelectionDAG::DAGUpdateListener*): Assertion `(!From->hasAnyUseOfValue(i) || From->getValueType(i) == To->getValueType(i)) && "Cannot use this version of ReplaceAllUsesWith!"' failed.
  Stack dump:
  0.	Running pass 'X86 DAG->DAG Instruction Selection' on function '@_ZN4llvm19AlphaTargetLowering14LowerOperationENS_7SDValueERNS_12SelectionDAGE'
  g++: Internal error: Aborted (program cc1plus)

This occurs when building LLVM using LLVM built by LLVM (via
dragonegg).  Probably LLVM has miscompiled itself, though it
may have miscompiled GCC and/or dragonegg itself: at this point
of the self-host build, all of GCC, LLVM and dragonegg were built
using LLVM.  Unfortunately this kind of thing is extremely hard
to debug, and while I did rummage around a bit I didn't find any
smoking guns, aka obviously miscompiled code.

Found by bisection.

r96556 | evancheng | 2010-02-18 03:13:50 +0100 (Thu, 18 Feb 2010) | 5 lines

Some dag combiner goodness:
Transform br (xor (x, y)) -> br (x != y)
Transform br (xor (xor (x,y), 1)) -> br (x == y)
Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm"

r96640 | evancheng | 2010-02-19 01:34:39 +0100 (Fri, 19 Feb 2010) | 16 lines

Transform (xor (setcc), (setcc)) == / != 1 to
(xor (setcc), (setcc)) != / == 1.

e.g. On x86_64
  %0 = icmp eq i32 %x, 0
  %1 = icmp eq i32 %y, 0
  %2 = xor i1 %1, %0
  br i1 %2, label %bb, label %return
=>
	testl   %edi, %edi
	sete    %al
	testl   %esi, %esi
	sete    %cl
	cmpb    %al, %cl
	je      LBB1_2

llvm-svn: 96672

Transform br (xor (x, y)) -> br (x != y)
Transform br (xor (xor (x,y), 1)) -> br (x == y)
Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm"

llvm-svn: 96556

If there exists a use of a build_vector that's the bitwise complement of the mask,
then transform the node to
(and (xor x, (build_vector -1,-1,-1,-1)), (build_vector ~c1,~c2,~c3,~c4)).

Since this transformation is only useful when 1) the given build_vector will
become a load from constpool, and 2) (and (xor x -1), y) matches to a single
instruction, I decided this is appropriate as a x86 specific transformation.
rdar://7323335

llvm-svn: 96389

Preliminary patch to improve dwarf EH generation - Hooks to return Personality / FDE / LSDA / TType encoding depending on target / options (e.g. code model / relocation model) - MCIzation of Dwarf EH printer to use encoding information - Stub generation for ELF target (needed for indirect references) - Some other small changes here and there

llvm-svn: 96285

Remove an assumption of default arguments.  This is in anticipation of a
change to SelectionDAG build APIs.

llvm-svn: 96228

isInteger, we now have isFloatTy and isIntegerTy.  Requested by Chris!

llvm-svn: 96223

This should fix alot of problems we saw so far, e.g. PRs 5851 & 2936

llvm-svn: 95980

use a multipattern that generates both the 1-byte and 4-byte 
versions from the same defm

llvm-svn: 95901

lowering and requires that certain types exist in ValueTypes.h.  Modified widening to
check if an op can trap and if so, the widening algorithm will apply only the op on
the defined elements.  It is safer to do this in widening because the optimizer can't
guarantee removing unused ops in some cases.

llvm-svn: 95823

llvm-svn: 95781

llvm-svn: 95593

its current purpose.

llvm-svn: 95564

Do not emit callseq instructions around sibcalls. This eliminated some unnecessary stack adjustments.

llvm-svn: 95475

llvm-svn: 95408

TSFlags directly instead of a TargetInstrDesc.

llvm-svn: 95405

llvm-svn: 95351

llvm-svn: 95295

Indirect tail call has to go through a call preserved register since it's after callee register pops. X86 isel lowering is using EAX / R11 and it was somehow adding that to function live out. That prevented the real function return register from being added to the function live out list and bad things happen.
This fixes 483.xalancbmk (with tail call opt).

llvm-svn: 95280

Speculatively disable x86 automatic tail call optimization while we track down a self-hosting issue.

llvm-svn: 95259

Allow all types of callee's to be tail called. But avoid automatic tailcall if the callee is a result of bitcast to avoid losing necessary zext / sext etc.

llvm-svn: 95195

ByVal frame object size should be that of the byval argument, not the size of the type which is just a pointer. This is not known to break stuff but is wrong nevertheless.

llvm-svn: 95163

llvm-svn: 95160

llvm-svn: 95130

where callee's arguments are already in the caller's own caller's stack and
they line up perfectly. e.g.

extern int foo(int a, int b, int c);

int bar(int a, int b, int c) {
  return foo(a, b, c);
}

llvm-svn: 95053

llvm-svn: 95017

llvm-svn: 94970

llvm-svn: 94949

llvm-svn: 94946

llvm-svn: 94873

llvm-svn: 94804

Fix a bug introduced by r94490 where it created a X86ISD::CMP whose output type is different from its inputs.
This fixes PR6146.

llvm-svn: 94731

even when -tailcallopt is not specified and it does not require changing ABI.
First case is the most trivial one. Perform tail call optimization when both
the caller and callee do not return values and when the callee does not take
any input arguments.

llvm-svn: 94664

Target independent isel should always pass along the "tail call" property. Change
target hook LowerCall's parameter "isTailCall" into a refernce. If the target
decides it's impossible to honor the tail call request, it should set isTailCall
to false to make target independent isel happy.

llvm-svn: 94626

llvm-svn: 94610

llvm-svn: 94583

llvm-svn: 94570

which is more convenient, and change getPICJumpTableRelocBaseExpr
to take a MachineFunction to match.

Next, move the X86 code that create a PICBase symbol to
X86TargetLowering::getPICBaseSymbol from 
X86MCInstLower::GetPICBaseSymbol, which was an asmprinter specific 
library.  This eliminates a 'gross hack', and allows us to
implement X86ISelLowering::getPICJumpTableRelocBaseExpr which now
calls it.

This in turn allows us to eliminate the 
X86AsmPrinter::printPICJumpTableSetLabel method, which was the
only overload of printPICJumpTableSetLabel.

llvm-svn: 94526

jump table entry kind, instead of overloading 
AsmPrinter::printPICJumpTableEntry.

This has a pretty horrible and inefficient FIXME around how @GOTOFF
is currently smashed into the mcsymbol name, but otherwise this is
much cleaner.

llvm-svn: 94516

llvm-svn: 94490

entries with @GOTOFF whih is EK_GPRel32BlockAddress.

llvm-svn: 94474