They are as much trouble as aliases to declarations. They are requiring
the code generator to define a symbol with the same value as another
symbol, but the second symbol is undefined.
If representing this is important for some optimization, we could add
support for available_externally aliases. They would be *required* to
point to a declaration (or available_externally definition).
llvm-svn: 254170
This patch implements a minimum spanning tree (MST) based instrumentation for
PGO. The use of MST guarantees minimum number of CFG edges getting
instrumented. An addition optimization is to instrument the less executed
edges to further reduce the instrumentation overhead. The patch contains both the
instrumentation and the use of the profile to set the branch weights.
Differential Revision: http://reviews.llvm.org/D12781
llvm-svn: 254021
We had two code paths. One would create names like "foo.1" and the other
names like "foo1".
For globals it is important to use "foo.1" to help C++ name demangling.
For locals there is no strong reason to go one way or the other so I
kept the most common mangling (foo1).
llvm-svn: 253804
Summary:
Several fixes to the handling of bitcode files without function summary
sections so that they are skipped during ThinLTO processing in llvm-lto
and the gold plugin when appropriate instead of aborting.
1 Don't assert when trying to add a FunctionInfo that doesn't have
a summary attached.
2 Skip FunctionInfo structures that don't have attached function summary
sections when trying to create the combined function summary.
3 In both llvm-lto and gold-plugin, check whether a bitcode file has
a function summary section before trying to parse the index, and skip
the bitcode file if it does not.
4 Fix hasFunctionSummaryInMemBuffer in BitcodeReader, which had a bug
where we returned to early while looking for the summary section.
Also added llvm-lto and gold-plugin based tests for cases where we
don't have function summaries in the bitcode file. I verified that
either the first couple fixes described above are enough to avoid the
crashes, or fixes 1,3,4. But have combined them all here for added
robustness.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D14903
llvm-svn: 253796
Terrifyingly, one of them is a mishandling of floating point vectors
in Constant::isZero(). How exactly this issue survived this long
is beyond me.
llvm-svn: 253655
The masked intrinsics support all integer and floating point data types. I added the pointer type to this list.
Added tests for CodeGen and for Loop Vectorizer.
Updated the Language Reference.
Differential Revision: http://reviews.llvm.org/D14150
llvm-svn: 253544
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.
This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.
There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe. For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.
For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)
For out of tree owners, I was able to strip alignment from calls using sed by replacing:
(call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
$1i1 false)
and similarly for memmove and memcpy.
I then added back in alignment to test cases which needed it.
A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.
In IRBuilder itself, a new argument was added. Instead of calling:
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)
There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool. This is to prevent isVolatile here from passing its default
parameter to the source alignment.
Note, changes in future can now be made to codegen. I didn't change anything here, but this
change should enable better memcpy code sequences.
Reviewed by Hal Finkel.
llvm-svn: 253511
Summary:
This change teaches LLVM's inliner to track and suitably adjust
deoptimization state (tracked via deoptimization operand bundles) as it
inlines through call sites. The operation is described in more detail
in the LangRef changes.
Reviewers: reames, majnemer, chandlerc, dexonsmith
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14552
llvm-svn: 253438
The way prelink used to work was
* The compiler decides if a given section only has relocations that
are know to point to the same DSO. If so, it names it
.data.rel.ro.local<something>.
* The static linker puts all of these together.
* The prelinker program assigns addresses to each library and resolves
the local relocations.
There are many problems with this:
* It is incompatible with address space randomization.
* The information passed by the compiler is redundant. The linker
knows if a given relocation is in the same DSO or not. If could sort
by that if so desired.
* There are newer ways of speeding up DSO (gnu hash for example).
* Even if we want to implement this again in the compiler, the previous
implementation is pretty broken. It talks about relocations that are
"resolved by the static linker". If they are resolved, there are none
left for the prelinker. What one needs to track is if an expression
will require only dynamic relocations that point to the same DSO.
At this point it looks like the prelinker is an historical curiosity.
For example, fedora has retired it because it failed to build for two
releases
(http://pkgs.fedoraproject.org/cgit/prelink.git/commit/?id=eb43100a8331d91c801ee3dcdb0a0bb9babfdc1f)
This patch removes support for it. That is, it stops printing the
".local" sections.
llvm-svn: 253280
Summary: Since we're passing references to dbg.value as pointers,
we need to have the frontend properly declare their sizes and
alignments (as it already does for regular pointers) in preparation
for my upcoming patch to have the verifer check that the sizes agree.
Also augment the backend logic that skips actually emitting this
information into DWARF such that it also handles reference types.
Reviewers: aprantl, dexonsmith, dblaikie
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D14275
llvm-svn: 253186
Summary: The Old personality function gets copied over, but the
Materializer didn't have a chance to inspect it (e.g. to fix up
references to the correct module for the target function).
Also add a verifier check that makes sure the personality routine
is in the same module as the function whose personality it is.
Reviewers: majnemer
Subscribers: jevinskie, llvm-commits
Differential Revision: http://reviews.llvm.org/D14474
llvm-svn: 253183
This reapplies r252949. I've changed the type of FuncName to be
std::string instead of StringRef in emitFnAttrCompatCheck.
Original commit message for r252949:
Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 252990
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 252949
When working with tokens, it is often the case that one has instructions
which consume a token and produce a new token. Currently, we have no
mechanism to represent an initial token state.
Instead, we can create a notional "empty token" by inventing a new
constant which captures the semantics we would like. This new constant
is called ConstantTokenNone and is written textually as "token none".
Differential Revision: http://reviews.llvm.org/D14581
llvm-svn: 252811
Summary:
This change introduces the notion of "deoptimization" operand bundles.
LLVM can recognize and optimize these in more precise ways than it can a
generic "unknown" operand bundles.
The current form of this special recognition / optimization is an enum
entry in LLVMContext, a LangRef blurb and a verifier rule. Over time we
will teach LLVM to do more aggressive optimization around deoptimization
operand bundles, exploiting known facts about kinds of state
deoptimization operand bundles are allowed to track.
Reviewers: reames, majnemer, chandlerc, dexonsmith
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14551
llvm-svn: 252806
This is a step towards consolidating some of the information regarding
attributes in a single place.
This patch moves the enum attributes in Attributes.h to the table-gen
file. Additionally, it adds definitions of target independent string
attributes that will be used in follow-up commits by the inliner to
check attribute compatibility.
rdar://problem/19836465
llvm-svn: 252796
This was an omission in the patch that landed initial support for
operand bundles. So far we haven't hit this, but we will once the
inliner is able to inline calls to functions that contain calls with
operand bundles.
llvm-svn: 252645
This marker prevents optimization passes from adding 'tail' or
'musttail' markers to a call. Is is used to prevent tail call
optimization from being performed on the call.
rdar://problem/22667622
Differential Revision: http://reviews.llvm.org/D12923
llvm-svn: 252368
This attribute allows the compiler to assume that the function never recurses into itself, either directly or indirectly (transitively). This can be used among other things to demote global variables to locals.
llvm-svn: 252282
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.
For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.
This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.
Since this is an IR change, a bitcode upgrade has been provided.
Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.
Differential Revision: http://reviews.llvm.org/D14265
llvm-svn: 252219
Summary:
Data operands of a call or invoke consist of the call arguments, and
the bundle operands associated with the `call` (or `invoke`)
instruction. The motivation for this change is that we'd like to be
able to query "argument attributes" like `readonly` and `nocapture`
for bundle operands naturally.
This change also provides a conservative "implementation" for these
attributes for any bundle operand, and an extension point for future
work.
Reviewers: chandlerc, majnemer, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14305
llvm-svn: 252077
Summary:
This is intended to make a later change simpler.
Note: adding this bounds checking required fixing `X86FastISel`. As
far I can tell I've preserved original behavior but a careful review
will be appreciated.
Reviewers: reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14304
llvm-svn: 252073
XOP has the VPCMOV instruction that performs the common vector bit select operation OR( AND( SRC1, SRC3 ), AND( SRC2, ~SRC3 ) )
This patch adds tablegen pattern matching for this instruction.
Differential Revision: http://reviews.llvm.org/D8841
llvm-svn: 251975
Summary:
An unsigned comparision is equivalent to is corresponding signed version
if both the operands being compared are positive. Teach SCEV to use
this fact when profitable.
Reviewers: atrick, hfinkel, reames, nlewycky
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13687
llvm-svn: 251051
Summary: This will be used in a future change to ScalarEvolution.
Reviewers: hfinkel, reames, nlewycky
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13612
llvm-svn: 250975
Summary:
This makes attribute accessors on `CallInst` and `InvokeInst` do the
(conservatively) right thing. This essentially involves, in some
cases, *not* falling back querying the attributes on the called
`llvm::Function` when operand bundles are present.
Attributes locally present on the `CallInst` or `InvokeInst` will still
override operand bundle semantics. The LangRef has been amended to
reflect this. Note: this change does not do anything prevent
`-function-attrs` from inferring `CallSite` local attributes after
inspecting the called function -- that will be done as a separate
change.
I've used `-adce` and `-early-cse` to test these changes. There is
nothing special about these passes (and they did not require any
changes) except that they seemed be the easiest way to write the tests.
This change does not add deal with `argmemonly`. That's a later change
because alias analysis requires a related fix before `argmemonly` can be
tested.
Reviewers: reames, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13961
llvm-svn: 250973
Stop converting implicitly between iterators and pointers/references in
lib/IR. For convenience, I've added a `getIterator()` accessor to
`ilist_node` so that callers don't need to know how to spell the
iterator class (i.e., they can use `X.getIterator()` instead of
`Function::iterator(X)`).
I'll eventually disallow these implicit conversions entirely, but
there's a lot of code, so it doesn't make sense to do it all in one
patch. One library or so at a time.
Why? To root out cases of `getNextNode()` and `getPrevNode()` being
used in iterator logic. The design of `ilist` makes that invalid when
the current node could be at the back of the list, but it happens to
"work" right now because of a bug where those functions never return
`nullptr` if you're using a half-node sentinel. Before I can fix the
function, I have to remove uses of it that rely on it misbehaving.
(Maybe the function should just be deleted anyway? But I don't want
deleting it -- potentially a huge project -- to block fixing
ilist/iplist.)
llvm-svn: 249782