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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62789 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62692 91177308-0d34-0410-b5e6-96231b3b80d8
we want to clear %ah to zero before a division, just use a
zero-extending mov to %al. This fixes PR3366.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62691 91177308-0d34-0410-b5e6-96231b3b80d8
as its comment says, even in the case where it will be generating
extending loads. This fixes PR3216.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62557 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62533 91177308-0d34-0410-b5e6-96231b3b80d8
optimize it to a SINT_TO_FP when the sign bit is known zero. X86 isel should perform the optimization itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62504 91177308-0d34-0410-b5e6-96231b3b80d8
simple %prcontext which doesn't find what it's looking for
if the scheduler has rearranged the instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62363 91177308-0d34-0410-b5e6-96231b3b80d8
to Eli for pointing out that these forms don't ignore the high bits of
their index operands, and as such are not immediately suitable for use
by isel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62194 91177308-0d34-0410-b5e6-96231b3b80d8
via two paths, process it once not twice, d'oh!
Analysis, testcase and original patch thanks to
Mon Ping Wang.
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Also future proof the scheduler to handle "normal" physical register dependencies. The code is not exercised yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62074 91177308-0d34-0410-b5e6-96231b3b80d8
v1024 = EDI // not killed
=
= EDI
One possible solution is for the coalescer to examine the sub-register live intervals in the same manner as the physical register. Another possibility is to examine defs and uses (when needed) of sub-registers. Both solutions are too expensive. For now, look for "short virtual intervals" and scan instructions to look for conflict instead.
This is a small win on x86-64. e.g. It shaves 403.gcc by ~80 instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61847 91177308-0d34-0410-b5e6-96231b3b80d8
into their left operand, rather than their right. Do this
by commuting the operands and inverting the condition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61842 91177308-0d34-0410-b5e6-96231b3b80d8
avoid the need for spilling, add a new testcase that tests that the
pcmpeqd used for V_SETALLONES is changed to a constant-pool load as
needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61831 91177308-0d34-0410-b5e6-96231b3b80d8
converted to LEA64_32r in x86's convertToThreeAddress. This
replaces code like this:
movl %esi, %edi
inc %edi
with this:
lea 1(%rsi), %edi
which appears to be beneficial.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61830 91177308-0d34-0410-b5e6-96231b3b80d8
AddPseudoTwoAddrDeps. This lets the scheduling infrastructure
avoid recalculating node heights. In very large testcases this
was a major bottleneck. Thanks to Roman Levenstein for finding
this!
As a side effect, fold-pcmpeqd-0.ll is now scheduled better
and it no longer requires spilling on x86-32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61778 91177308-0d34-0410-b5e6-96231b3b80d8
