1. Legalize now always promotes truncstore of i1 to i8. 
2. Remove patterns and gunk related to truncstore i1 from targets.
3. Rename the StoreXAction stuff to TruncStoreAction in TLI.
4. Make the TLI TruncStoreAction table a 2d table to handle from/to conversions.
5. Mark a wide variety of invalid truncstores as such in various targets, e.g.
   X86 currently doesn't support truncstore of any of its integer types.
6. Add legalize support for truncstores with invalid value input types.
7. Add a dag combine transform to turn store(truncate) into truncstore when
   safe.

The later allows us to compile CodeGen/X86/storetrunc-fp.ll to:

_foo:
	fldt	20(%esp)
	fldt	4(%esp)
	faddp	%st(1)
	movl	36(%esp), %eax
	fstps	(%eax)
	ret

instead of:

_foo:
	subl	$4, %esp
	fldt	24(%esp)
	fldt	8(%esp)
	faddp	%st(1)
	fstps	(%esp)
	movl	40(%esp), %eax
	movss	(%esp), %xmm0
	movss	%xmm0, (%eax)
	addl	$4, %esp
	ret

llvm-svn: 46140

  and switch various codegen pieces and the X86 backend over
  to using it.

* Add some comments to SelectionDAGNodes.h

* Introduce a second argument to FP_ROUND, which indicates
  whether the FP_ROUND changes the value of its input. If
  not it is safe to xform things like fp_extend(fp_round(x)) -> x.

llvm-svn: 46125

it should work, but I have no machine to test
it on.  Committed because it will at least
cause no harm, and maybe someone can test it
for me!

llvm-svn: 46098

llvm-svn: 46058

some code.  No functionality change.

llvm-svn: 46055

make the 'fp return in ST(0)' optimization smart enough to
look through token factor nodes.  THis allows us to compile 
testcases like CodeGen/X86/fp-stack-retcopy.ll into:

_carg:
	subl	$12, %esp
	call	L_foo$stub
	fstpl	(%esp)
	fldl	(%esp)
	addl	$12, %esp
	ret

instead of:

_carg:
	subl	$28, %esp
	call	L_foo$stub
	fstpl	16(%esp)
	movsd	16(%esp), %xmm0
	movsd	%xmm0, 8(%esp)
	fldl	8(%esp)
	addl	$28, %esp
	ret

Still not optimal, but much better and this is a trivial patch.  Fixing 
the rest requires invasive surgery that is is not llvm 2.2 material.

llvm-svn: 46054

look through token factor

llvm-svn: 46053

llvm-svn: 46052

ShortenEHDataFor64Bits as a not-very-accurate
abstraction to cover all the changes in DwarfWriter.
Some cosmetic changes to Darwin assembly code for
gcc testsuite compatibility.

llvm-svn: 46029

Move definition of 'trap' sdnode up from x86 instrinfo to targetselectiondag.td.

llvm-svn: 46017

llvm-svn: 46015

llvm-svn: 46012

as well as PPC codegen

llvm-svn: 46001

Rename CCIfStruct to CCIfByVal and CCStructAssign to CCPassByVal. Remove unused parameters of CCStructAssign and add size and alignment requirement info.

llvm-svn: 45997

llvm-svn: 45996

an instruction kills a register or not.  This is cheap and 
easy to do now that instructions record this on their flags,
and this eliminates the second pass of LiveVariables from the
x86 backend.  This speeds up a release llc by ~2.5%.

llvm-svn: 45955

llvm-svn: 45940

llvm-svn: 45898

llvm-svn: 45896

This allows us to sink things like:
	cvtsi2sd	32(%esp), %xmm1
when reading from the argument area, for example.

llvm-svn: 45895

llvm-svn: 45871

llvm-svn: 45870

llvm-svn: 45869

Actually were not riding any arguments. Sadly there is no semantic spell checker that is going to safe you from such a mistake.

llvm-svn: 45868

commit all arguments where moved to the stack slot where they would
reside on a normal function call before the lowering to the tail call
stack slot. This was done to prevent arguments overwriting each other.
Now only arguments sourcing from a FORMAL_ARGUMENTS node or a
CopyFromReg node with virtual register (could also be a caller's
argument) are lowered indirectly.

 --This line, and those below, will be ignored--

M    X86/X86ISelLowering.cpp
M    X86/README.txt

llvm-svn: 45867

llvm-svn: 45865

llvm-svn: 45861

llvm-svn: 45860

llvm-svn: 45859

Cosmetic changes to spacing to match gcc (some dejagnu
tests actually care).

llvm-svn: 45848

both work right according to the new flags.

This removes the TII::isReallySideEffectFree predicate, and adds
TII::isInvariantLoad. 

It removes NeverHasSideEffects+MayHaveSideEffects and adds
UnmodeledSideEffects as machine instr flags.  Now the clients
can decide everything they need.

I think isRematerializable can be implemented in terms of the
flags we have now, though I will let others tackle that.

llvm-svn: 45843

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