XFAIL this test.  It only worked before because of a bug in the spill point selection code.  Not deleting because 
it should be possible to enhance the selection code to handle this in the future.

llvm-svn: 63340

Local register allocator shouldn't assume only the entry and landing pad basic blocks have live-ins.

llvm-svn: 63323

the element indices may be equal if either one is not a
constant.

llvm-svn: 63311

llvm-svn: 63267

dagcombines that help it match in several more cases. Add
several more cases to test/CodeGen/X86/bt.ll. This doesn't
yet include matching for BT with an immediate operand, it
just covers more register+register cases.

llvm-svn: 63266

llvm-svn: 63252

llvm-svn: 63247

The memory alignment requirement on some of the mov{h|l}p{d|s} patterns are 16-byte. That is overly strict. These instructions read / write f64 memory locations without alignment requirement.

llvm-svn: 63195

llvm-svn: 63194

llvm-svn: 63149

llvm-svn: 63090

llvm-svn: 63075

checking logic.  Rather than make the checking more
complicated, I've tweaked some logic to make things
conform to how the checking thought things ought to
be, since this results in a simpler "mental model".

llvm-svn: 63048

llvm-svn: 63042

Enhance logic in X86DAGToDAGISel::PreprocessForRMW which move load inside callseq_start to allow it to be folded into a call. It was not considering the cases where a token factor is between the load and the callseq_start.

llvm-svn: 63022

other x86 segments.  address space 0 is stack/default, 1-255 are reserved for
client use.

llvm-svn: 62980

for example in the case of va-args. XFAIL associated tests.

llvm-svn: 62972

llvm-svn: 62967

Teach 2addr pass to be do more commuting. If both uses of a two-address instruction are killed, but the first operand has a use before and after the def, commute if the second operand does not suffer from the same issue.
%reg1028<def> = EXTRACT_SUBREG %reg1027<kill>, 1                                                                                                                                     
%reg1029<def> = MOV8rr %reg1028                                                                                                                                                      
%reg1029<def> = SHR8ri %reg1029, 7, %EFLAGS<imp-def,dead>                                                                                                                            
insert => %reg1030<def> = MOV8rr %reg1028                                                                                                                                            
%reg1030<def> = ADD8rr %reg1028<kill>, %reg1029<kill>, %EFLAGS<imp-def,dead>                                                                                                         

In this case, it might not be possible to coalesce the second MOV8rr                                                                                                                 
instruction if the first one is coalesced. So it would be profitable to                                                                                                              
commute it:                                                                                                                                                                          
%reg1028<def> = EXTRACT_SUBREG %reg1027<kill>, 1                                                                                                                                     
%reg1029<def> = MOV8rr %reg1028                                                                                                                                                      
%reg1029<def> = SHR8ri %reg1029, 7, %EFLAGS<imp-def,dead>                                                                                                                            
insert => %reg1030<def> = MOV8rr %reg1029                                                                                                                                            
%reg1030<def> = ADD8rr %reg1029<kill>, %reg1028<kill>, %EFLAGS<imp-def,dead>

llvm-svn: 62954

llvm-svn: 62921

llvm-svn: 62836

Simplify x+0 to x in unsafe-fp-math mode. This avoids a bunch of
redundant work in many cases, because in unsafe-fp-math mode,
ISD::FADD with a constant is considered free to negate, so the
DAGCombiner often negates x+0 to -0-x thinking it's free, when
in reality the end result is -x, which is more expensive than x.

Also, combine x*0 to 0.

This fixes PR3374.

llvm-svn: 62789

llvm-svn: 62770

llvm-svn: 62716

llvm-svn: 62714

special cases after producing the new reduced-width load, because the
new load already has the needed adjustments built into it. This fixes
several bugs due to the special cases, including PR3317.

llvm-svn: 62692

we want to clear %ah to zero before a division, just use a
zero-extending mov to %al. This fixes PR3366.

llvm-svn: 62691

unsigned test(unsigned a) {
  return ~a;
}
llvm used to generate:
movl    $4294967295, %eax
xorl    4(%esp), %eax

Now it generates:
movl      4(%esp), %eax
notl      %eax

It's 3 bytes shorter.

llvm-svn: 62661

llvm-svn: 62639

Fix PR3243: a LiveVariables bug. When HandlePhysRegKill is checking whether the last reference is also the last def (i.e. dead def), it should also check if last reference is the current machine instruction being processed. This can happen when it is processing a physical register use and setting the current machine instruction as sub-register's last ref.

llvm-svn: 62617

llvm-svn: 62604

llvm-svn: 62572

as its comment says, even in the case where it will be generating
extending loads. This fixes PR3216.

llvm-svn: 62557

llvm-svn: 62547

llvm-svn: 62538

uses are added to the From node while it is processing From's
use list, because of automatic local CSE. The fix is to avoid
visiting any new uses.

Fix a few places in the DAGCombiner that assumed that after
a RAUW call, the From node has no users and may be deleted.

This fixes PR3018.

llvm-svn: 62533

llvm-svn: 62528

DIVREM isel deficiency: If sign bit is known zero, zero out DX/EDX/RDX instead of sign extending the low part (in AX/EAX/RAX) into it.

llvm-svn: 62519

optimize it to a SINT_TO_FP when the sign bit is known zero. X86 isel should perform the optimization itself.

llvm-svn: 62504

llvm-svn: 62470