Not folding these cases tends to avoid partial register updates:
sqrtss (%eax), %xmm0
Has a partial update of %xmm0, while
movss (%eax), %xmm0
sqrtss %xmm0, %xmm0
Has a clobber of the high lanes immediately before the partial update,
avoiding a potential stall.
Given this, we only want to fold when optimizing for size.
This is consistent with the patterns we already have for some of
the fp/int converts, and in X86InstrInfo::foldMemoryOperandImpl()
Differential Revision: http://reviews.llvm.org/D15741
llvm-svn: 256671
This restores the previous behavior of not including the mnemonic in the classes table for every target that starts instruction lines with the mnemonic. Not only did the table size increase by 1 entry, but the class enum increased in size which caused every class in the array to increase in size. It also grew the size of the function that parsers tokens into classes by a substantial amount.
This adds a new HasMnemonicFirst flag to all AsmParsers. It's set to 1 by default and Hexagon target overrides it to 0.
For the X86 target alone this recovers 324KB of size on the llvm-mc executable.
I believe the current state is still a bad design choice for the Hexagon target as it causes most of the parsing to do a linear search through the entire match table to comparing operands against every instruction until it finds one that works. At least for the other targets we do a binary search based on mnemonic over which to do the linear scan.
llvm-svn: 256669
This is part of the effort/prepration to reduce the size
instr-pgo (object, binary, memory footprint, and raw data).
The functionality is currently off by default and not yet
used by any clients.
llvm-svn: 256667
This reverts commit r256642 and restores r256620 now that Tobias has
updated Polly.
There are still some potential problems with the code in Polly that I've
sent post-commit review about, but they're unlikely to break anything in
practice, and I'd like to avoid the rest of LLVM and Clang regressing
here.
llvm-svn: 256656
As suggested in review for r255909, rename MDMaterialized to AllowTemps,
and identify the name of the boolean flag being set in calls to
saveMetadataList.
llvm-svn: 256653
As suggested in review for r255909, add a way to ensure that temporary
MD used as keys in the MetadataToID map during ThinLTO importing are not
RAUWed.
Add support for marking an MDNode as not replaceable. Clear the new
CanReplace flag when adding a temporary MD node to the MetadataToID map
and clear it when destroying the map.
llvm-svn: 256648
Add an assert suggested in review for r255909 to ensure that MDNodes
saved in the map used for metadata linking are either temporary or
resolved.
Also add a comment clarifying why we may need to save off non-MDNode
metadata.
llvm-svn: 256646
The commit we revert is rather small, but it enables a larger piece of new
infrastructure that allows to detected misuses of pointer-traits at compile
time. Unfortunately, this change breaks with the use of incomplete types (e.g.
in Polly). As I am not aware of a simple fix on the Polly side, I temporarely
revert this commit to clean the bots and sync-up with Chandler how to best
adapt to these recent changes.
This reverts commit https://llvm.org/svn/llvm-project/llvm/trunk@256620.
llvm-svn: 256642
alignment of the pointee type!
This is the culmination of the ptr-traits work. Now the compiler will
catch me if I try to use a pointer to an empty struct as a key in
a dense map or inside a PointerIntPair or PointerUnion! This is much,
much better than sometimes corrupting data (and other times working
fine) due to insufficient alignment.
It also means that we will be much more diligent about rejecting other
uses of these constructs that aren't safe.
It also means that we can now be more aggressive with the constructs
when we actually have guaranteed higher alignment without specializing
stuff. I'll be going through and cleaning up all the current overrides
of these traits which are no longer necessary.
Many thanks to Richard, David, and others who helped me get all of this
together.
llvm-svn: 256620
to isolate it in a dependent helper class.
Without doing this, we end up requiring all of the pointer traits the
moment you even define a PointerIntPair. That makes them *incredibly*
hard to use, for example you can't use them at all inside a class for
pointers to that class!
This change sinks all the logic into a helper template class that only
needs to be fully instantiated when *using* the PointerIntPair. We still
get compile-time checking, but it is deferred long enough to make
tradition out-of-line method definitions (or just the normal deferred
method body parsing) sufficient to handle cycling references.
llvm-svn: 256618
If running the PlaceSafepoints pass on a module which doesn't have the
gc.safepoint_poll function without disabling entry and backedge safepoints,
previously the pass crashed with an obscure error because of a null pointer.
Now it fails the assert instead.
llvm-svn: 256580
The code that was meant to adjust the duplication cost based on the
terminator opcode was not being executed in cases where the initial
threshold was hit inside the loop.
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D15536
llvm-svn: 256568
This is necessary to use them as part of pointer traits and is generally
useful. I've added unit test coverage to isolate and ensure this works
correctly.
I'll watch the build bots to try to see if any compilers can't tolerate
this bit of magic (and much credit goes to Richard Smith for coming up
with this magical production!) but give a shout if you see issues.
llvm-svn: 256553
of casting the integer '4' to such a pointer. There is no reason to
expect '4' to be a portable or reliable pointer of this form. The only
reason this ever worked is because the PointerIntPair that this actually
gets used with has an artificially *low* presumed alignment that allowed
it to work. When the alignment of PointerIntPair is derived from the
actual type's alignment, the asserts start firing on this pointer. I'm
amazed we never managed to do anything that triggered the alignment
sanitizer with it, as this is just flat out UB.
If folks dislike this approach to providing a sentinel fragment address,
there are a myriad of other alternatives, suggestions welcome. But this
one has the distinct advantage of not requiring the friend dance of
ilist's sentinel (which I'll point out is *also* in play for
MCFragment!) and seems to be using a nicely provided facility in
MCFragment to establish just such dummy nodes.
This is part of a series of patches to allow LLVM to check for complete
pointee types when computing its pointer traits. This is absolutely
necessary to get correct (or reproducible) results for things like how
many low bits are guaranteed to be zero.
llvm-svn: 256552
inline definitions after the mutually recursive pair of types have been
defined. The two types mutually recurse specifically through
abstractions that require pointer traits which makes this kind of mutual
recursion especially tricky to get right in terms of ordering.
This is part of a series of patches to allow LLVM to check for complete
pointee types when computing its pointer traits. This is absolutely
necessary to get correct (or reproducible) results for things like how
many low bits are guaranteed to be zero.
llvm-svn: 256551
missing includes so that the pointee types for DenseMap pointer keys and
such are complete prior to us querying the pointer traits for them.
This is part of a series of patches to allow LLVM to check for complete
pointee types when computing its pointer traits. This is absolutely
necessary to get correct (or reproducible) results for things like how
many low bits are guaranteed to be zero.
llvm-svn: 256550
