This adds some comments and splits the flag calculation on type boundaries to
make the table more readable. Addresses some post-commit review comments to SVN
r227603. NFC.
llvm-svn: 227670
type erased interface and a single analysis pass rather than an
extremely complex analysis group.
The end result is that the TTI analysis can contain a type erased
implementation that supports the polymorphic TTI interface. We can build
one from a target-specific implementation or from a dummy one in the IR.
I've also factored all of the code into "mix-in"-able base classes,
including CRTP base classes to facilitate calling back up to the most
specialized form when delegating horizontally across the surface. These
aren't as clean as I would like and I'm planning to work on cleaning
some of this up, but I wanted to start by putting into the right form.
There are a number of reasons for this change, and this particular
design. The first and foremost reason is that an analysis group is
complete overkill, and the chaining delegation strategy was so opaque,
confusing, and high overhead that TTI was suffering greatly for it.
Several of the TTI functions had failed to be implemented in all places
because of the chaining-based delegation making there be no checking of
this. A few other functions were implemented with incorrect delegation.
The message to me was very clear working on this -- the delegation and
analysis group structure was too confusing to be useful here.
The other reason of course is that this is *much* more natural fit for
the new pass manager. This will lay the ground work for a type-erased
per-function info object that can look up the correct subtarget and even
cache it.
Yet another benefit is that this will significantly simplify the
interaction of the pass managers and the TargetMachine. See the future
work below.
The downside of this change is that it is very, very verbose. I'm going
to work to improve that, but it is somewhat an implementation necessity
in C++ to do type erasure. =/ I discussed this design really extensively
with Eric and Hal prior to going down this path, and afterward showed
them the result. No one was really thrilled with it, but there doesn't
seem to be a substantially better alternative. Using a base class and
virtual method dispatch would make the code much shorter, but as
discussed in the update to the programmer's manual and elsewhere,
a polymorphic interface feels like the more principled approach even if
this is perhaps the least compelling example of it. ;]
Ultimately, there is still a lot more to be done here, but this was the
huge chunk that I couldn't really split things out of because this was
the interface change to TTI. I've tried to minimize all the other parts
of this. The follow up work should include at least:
1) Improving the TargetMachine interface by having it directly return
a TTI object. Because we have a non-pass object with value semantics
and an internal type erasure mechanism, we can narrow the interface
of the TargetMachine to *just* do what we need: build and return
a TTI object that we can then insert into the pass pipeline.
2) Make the TTI object be fully specialized for a particular function.
This will include splitting off a minimal form of it which is
sufficient for the inliner and the old pass manager.
3) Add a new pass manager analysis which produces TTI objects from the
target machine for each function. This may actually be done as part
of #2 in order to use the new analysis to implement #2.
4) Work on narrowing the API between TTI and the targets so that it is
easier to understand and less verbose to type erase.
5) Work on narrowing the API between TTI and its clients so that it is
easier to understand and less verbose to forward.
6) Try to improve the CRTP-based delegation. I feel like this code is
just a bit messy and exacerbating the complexity of implementing
the TTI in each target.
Many thanks to Eric and Hal for their help here. I ended up blocked on
this somewhat more abruptly than I expected, and so I appreciate getting
it sorted out very quickly.
Differential Revision: http://reviews.llvm.org/D7293
llvm-svn: 227669
Now that -mstack-probe-size is piped through to the backend via the function
attribute as on Windows x86, honour the value to permit handling of non-default
values for stack probes. This is needed /Gs with the clang-cl driver or
-mstack-probe-size with the clang driver when targeting Windows on ARM.
llvm-svn: 227667
Also revert r227489 since it didn't actually fix the thing I thought I
was fixing (since the test case was targeting the wrong architecture
initially). The change might be correct & demonstrated by other test
cases, but it's not a priority for me to find those test cases right
now.
Filed PR22417 for the failure.
llvm-svn: 227632
MSDN's x64 software conventions page says that this is one of the fixed
list of legal epilogues:
https://msdn.microsoft.com/en-us/library/tawsa7cb.aspx
Presumably this is how the unwinder distinguishes epilogue jumps from
in-function control flow.
Also normalize the way we place "## TAILCALL" comments on such jumps.
llvm-svn: 227611
Add tie breaker to colorChainSet() sort so that processing order doesn't
depend on std::set order, which depends on pointer order, which is
unstable from run to run.
No test case as this is nearly impossible to reproduce.
Phabricator Review: http://reviews.llvm.org/D7265
Patch by Geoff Berry <gberry@codeaurora.org>!
llvm-svn: 227606
If the original FPU specification involved a restricted VFP unit (d16), ensure
that we reset the functionality when we encounter a new FPU type. In
particular, if the user specified vfpv3-d16, but switched to a VFPv3 (which has
32 double precision registers), we would fail to reset the D16 feature, and
treat it as being equivalent to vfpv3-d16.
llvm-svn: 227603
The FPU directive permits the user to switch the target FPU, enabling
instructions that would be otherwise unavailable. However, when configuring the
new subtarget features, we would not enable the implied functions for newer
FPUs. This would result in invalid rejection of valid input. Ensure that we
inherit the implied FPU functionality when enabling newer versions of the FPU.
Fortunately, these are mostly hierarchical, unlike the CPUs.
Addresses PR22395.
llvm-svn: 227584
Summary:
This is needed by the .cprestore assembler directive.
This directive needs to be able to insert an LW instruction after every JALR replacement of a JAL pseudo-instruction
(and never after a JALR which has NOT been a result of a pseudo-instruction replacement).
The problem with using InstAlias for these is that after it replaces the pseudo-instruction, we can't find out if the resulting JALR instruction
was generated by an InstAlias or not, so we don't know whether or not to insert our LW instruction.
By replacing it manually, we know when the pseudo-instruction replacement happens and we can insert the LW instruction correctly.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D5601
llvm-svn: 227568
In the large code model, we now put __chkstk in %r11 before calling it.
Refactor the code so that we only do this once. Simplify things by using
__chkstk_ms instead of __chkstk on cygming. We already use that symbol
in the prolog emission, and it simplifies our logic.
Second half of PR18582.
llvm-svn: 227519
calls that don't take a Function argument from Mips. Notable
exceptions: the AsmPrinter and MipsTargetObjectFile. The
latter needs to be fixed, and the former will be fixed when the
general AsmPrinter changes happen.
llvm-svn: 227512
These are needed so this pass will produce output when
e.g. -print-after-all is used.
Phabricator Review: http://reviews.llvm.org/D7264
Patch by Geoff Berry <gberry@codeaurora.org>!
llvm-svn: 227506
