llvm-svn: 46930

has no stores between the load and the end of block.  This works 
great and sinks hundreds of stores, but we can't turn it on because
machineinstrs don't have volatility information and we don't want to
sink volatile stores :(

llvm-svn: 45894

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: 45841

llvm-svn: 45625

llvm-svn: 45617

llvm-svn: 45614

It is missing validity checks, so it is known broken.  However, it is powerful enough
to compile this contrived code:

void test1(int C, double A, double B, double *P) {
  double Tmp = A*A+B*B;
  *P = C ? Tmp : A;
}

into:

_test1:
	movsd	8(%esp), %xmm0
	cmpl	$0, 4(%esp)
	je	LBB1_2	# entry
LBB1_1:	# entry
	movsd	16(%esp), %xmm1
	mulsd	%xmm1, %xmm1
	mulsd	%xmm0, %xmm0
	addsd	%xmm1, %xmm0
LBB1_2:	# entry
	movl	24(%esp), %eax
	movsd	%xmm0, (%eax)
	ret

instead of:

_test1:
	movsd	16(%esp), %xmm0
	mulsd	%xmm0, %xmm0
	movsd	8(%esp), %xmm1
	movapd	%xmm1, %xmm2
	mulsd	%xmm2, %xmm2
	addsd	%xmm0, %xmm2
	cmpl	$0, 4(%esp)
	je	LBB1_2	# entry
LBB1_1:	# entry
	movapd	%xmm2, %xmm1
LBB1_2:	# entry
	movl	24(%esp), %eax
	movsd	%xmm1, (%eax)
	ret

woo.

llvm-svn: 45570