This is a step towards removing the rampant undefined behaviour in
SelectionDAG, which is a part of llvm.org/PR26808.
We rename SelectionDAGISel::Select to SelectImpl and update targets to
match, and then change Select to return void and consolidate the
sketchy behaviour we're trying to get away from there.
Next, we'll update backends to implement `void Select(...)` instead of
SelectImpl and eventually drop the base Select implementation.
llvm-svn: 268693
Both Linux and kFreeBSD use glibc, so follow similiar code paths.
Add isTargetGlibc to check for this, and use it instead of isTargetLinux
in a few places.
Fixes PR22248 for kFreeBSD.
Differential Revision: http://reviews.llvm.org/D19104
llvm-svn: 268624
The result type of setcc is dependent on whether or not AVX512 is
present.
We had an X86-specific DAG-combine which assumed that the result type
should be i8 when it could be i1.
This meant that we would generate illegal setccs which LowerSETCC did
not like.
Instead, use an appropriate type and zero extend to i8.
Also, there were some scenarios where the fold should have fired but
didn't because we were overly cautious about the types. This meant that
we generated:
shrl $31, %edi
andl $1, %edi
kmovw %edi, %k0
kxnorw %k0, %k0, %k1
kshiftrw $15, %k1, %k1
kxorw %k1, %k0, %k0
kmovw %k0, %eax
instead of:
testl %edi, %edi
setns %al
This fixes PR27638.
llvm-svn: 268609
The new register classes allow to tell the machine verifier that it is
fine to use RIP for address accesses in x32 mode. Prior to that patch,
we would complain that we are using a GR64 in place of GR32, whereas it
is actually fine to use GR64 for x32 as long as the 32 high bits are 0s.
RIP has this property and is used for RIP-relative addressing.
This partially fixes http://llvm.org/PR27481.
llvm-svn: 268567
i1 is now a legal type for X86 with AVX512.
There were some paths in X86FastISel which were not quite ready to see
an i1 value: they were not quite sure how to deal with sign/zero extends
for call arguments.
DTRT by extending to i8 for zeroext and bailing out of FastISel for
signext.
This fixes PR27591.
llvm-svn: 268470
Remove the AddPristinesAndCSRs parameters from
addLiveIns()/addLiveOuts().
We need to respect pristine registers after prologue epilogue insertion,
Seeing that we got this wrong in at least two commits already, we should
rather pay the small price to query MachineFrameInfo for it.
There are three cases that did not set AddPristineAndCSRs to true even
after register allocation:
- ExecutionDepsFix: live-out registers are used as a hint that the
register is used soon. This is not true for pristine registers so
use the new addLiveOutsNoPristines() to maintain this behaviour.
- SystemZShortenInst: Not setting AddPristineAndCSRs to true looks like
a bug, should do the right thing automatically now.
- StackMapLivenessAnalysis: Not adding pristine registers looks like a
bug to me. Added a FIXME comment but maintain the current behaviour
as a change may need to get coordinated with GC runtimes.
llvm-svn: 268336
This operation may branch to the handler block and we do not want it
to happen anywhere within the basic block.
Moreover, by marking it "terminator and branch" the machine verifier
does not wrongly assume (because of AnalyzeBranch not knowing better)
the branch is analyzable. Indeed, the target was seeing only the
unconditional branch and not the faulting load op and thought it was
a simple unconditional block.
The machine verifier was complaining because of that and moreover,
other optimizations could have done wrong transformation!
In the process, simplify the representation of the handler block in
the faulting load op. Now, we directly reference the handler block
instead of using a label. This has the benefits of:
1. MC knows how to issue a label for a BB, so leave that to it.
2. Accessing the target BB from its label is painful, whereas it is
direct from a MBB operand.
Note: The 2 bytes offset in implicit-null-check.ll comes from the
fact the unconditional jumps are not removed anymore, as the whole
terminator sequence is not analyzable anymore.
Will fix it in a subsequence commit.
llvm-svn: 268327
This didn't cause a bug because the order of the patterns ensured that the 64-bit instructions with 32-bit immediates were selected first.
llvm-svn: 268212
Summary:
Historically, we had a switch in the Makefiles for turning on "expensive
checks". This has never been ported to the cmake build, but the
(dead-ish) code is still around.
This will also make it easier to turn it on in buildbots.
Reviewers: chandlerc
Subscribers: jyknight, mzolotukhin, RKSimon, gberry, llvm-commits
Differential Revision: http://reviews.llvm.org/D19723
llvm-svn: 268050
For compilations with no explicit cpu specified, this exhibits
nice gains on Silvermont, with neutral performance on big cores.
Differential Revision: http://reviews.llvm.org/D19138
llvm-svn: 267809
The callseq_end node must be glued with the TLS calls, otherwise,
the generic code will miss the uses of the returned value and will
mark it dead.
Moreover, TLSCall 64-bit pseudo must not set an implicit-use on RDI,
the pseudo uses the symbol address at this point not RDI and the
lowering will do the right thing.
llvm-svn: 267797
We run after PEI, so we need to AddPristinesAndCSRs.
In practice, that makes no difference here, because we only ask about
liveness of super-registers of defined GR8/GR16 registers, so they
can't be pristine. Still, it's the correct thing to do.
Thanks to Quentin for noticing!
Follow-up to r267495.
llvm-svn: 267658
This effectively adds back the extractelt combine removed by r262358:
the direct case can still occur (because x86_mmx is special, see
r262446), but it's the indirect case that's now superseded by the
generic combine.
llvm-svn: 267651
the prologue.
Do not use basic blocks that have EFLAGS live-in as prologue if we need
to realign the stack. Realigning the stack uses AND instruction and this
clobbers EFLAGS.
An other alternative would have been to save and restore EFLAGS around
the stack realignment code, but this is likely inefficient.
Fixes PR27531.
llvm-svn: 267634
Justin Bogner