llvm-svn: 45838

x86 backend where instructions were not marked maystore/mayload, and perf issues where
instructions were not marked neverHasSideEffects.  It would be really nice if we could
write patterns for copy instructions.

I have audited all the x86 instructions down to MOVDQAmr.  The flags on others and on
other targets are probably not right in all cases, but no clients currently use this
info that are enabled by default.

llvm-svn: 45829

llvm-svn: 45826

inferred from the instr patterns.

llvm-svn: 45824

llvm-svn: 45821

or being side-effect free.

llvm-svn: 45816

llvm-svn: 45813

because assembler/linker can't cope with weak absolutes.
PR 1880.

llvm-svn: 45811

Do not use the stack pointer directly, issue a copyfromreg instead. Otherwise we can end up with something like ADD32ri %esp, x which two-address pass won't like.

llvm-svn: 45798

llvm-svn: 45792

llvm-svn: 45768

on 64-bit builds.  Analysis and original patch
by Török Edwin.  Code audit found another place
with the same problem, also fixed here.

llvm-svn: 45746

llvm-svn: 45734

llvm-svn: 45733

llvm-svn: 45731

llvm-svn: 45725

llvm-svn: 45723

llvm-svn: 45703

llvm-svn: 45701

llvm-svn: 45699

Make MachineInstr::getDesc return a reference instead
of a pointer, since it can never be null.

llvm-svn: 45695

Evan, please review the comments I added to getNumDefs to make sure
that they are accurate, thx.

llvm-svn: 45687

llvm-svn: 45680

llvm-svn: 45679

over to using them, instead of diddling Flags directly.  Change the
various flags from const variables to enums.

llvm-svn: 45677

that it is cheap and efficient to get.

Move a variety of predicates from TargetInstrInfo into 
TargetInstrDescriptor, which makes it much easier to query a predicate
when you don't have TII around.  Now you can use MI->getDesc()->isBranch()
instead of going through TII, and this is much more efficient anyway. Not
all of the predicates have been moved over yet.

Update old code that used MI->getInstrDescriptor()->Flags to use the
new predicates in many places.

llvm-svn: 45674

Some day I'll get it all moved over...

llvm-svn: 45672

llvm-svn: 45668

llvm-svn: 45667

llvm-svn: 45638

the target independent legalizer.

llvm-svn: 45631

unifying the copied algorithms and saving over 500 LOC. There should
be no functionality change, but please test on your favorite x86
target.

llvm-svn: 45627

checking that there was a from a global instead of a load from the stub
for a global, which is the one that's safe to hoist.

Consider this program:

volatile char G[100];
int B(char *F, int N) {
  for (; N > 0; --N)
    F[N] = G[N];
}

In static mode, we shouldn't be hoisting the load from G:

$ llc -relocation-model=static -o - a.bc -march=x86 -machine-licm

LBB1_1: # bb.preheader
        leal    -1(%eax), %edx
        testl   %edx, %edx
        movl    $1, %edx
        cmovns  %eax, %edx
        xorl    %esi, %esi
LBB1_2: # bb
        movb    _G(%eax), %bl
        movb    %bl, (%ecx,%eax)

llvm-svn: 45626

for remat, but can't due to an RA bug.

llvm-svn: 45623

llvm-svn: 45622

llvm-svn: 45621

isReallySideEffectFree and isReallyTriviallyReMaterializable.  Why is a load from
a global considered side-effect-free but not rematable?

llvm-svn: 45620

llvm-svn: 45618

llvm-svn: 45616

llvm-svn: 45605