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 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
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
Gets a bit tricky in the ValueMapper, of course - not sure if we should
just expose a list of explicit types for each Value so that the
ValueMapper can be neutral to these special cases (it's OK for things
like load, where the explicit type is the result type - but when that's
not the case, it means plumbing through another "special" type... )
llvm-svn: 245728
This is part of the work to devirtualize Value.
The old pattern was to call replaceUsesOfWithOnConstant which was overridden by
subclasses. Those could then call replaceUsesOfWithOnConstantImpl on Constant
to handle deleting the current value.
To be consistent with other parts of the code, this has been changed so that we
call the method on Constant, and that dispatches to an Impl on subclasses.
As part of this, it made sense to rename the methods to be more descriptive. The
new name is Constant::handleOperandChange, and it requires that all subclasses of
Constant implement handleOperandChangeImpl, even if they just throw an error if
they shouldn't be called.
Reviewed by Duncan Exon Smith.
llvm-svn: 240567
This reorganizes destroyConstant and destroyConstantImpl.
Now there is only destroyConstant in Constant itself, while
subclasses are required to implement destroyConstantImpl.
destroyConstantImpl no longer calls delete but is instead only
responsible for removing the constant from any maps in which it
is contained.
Reviewed by Duncan Exon Smith.
llvm-svn: 240471
We don't want anyone to access OperandList directly as its going to be removed
and computed instead. This uses getter's and setter's instead in which we
can later change the underlying implementation of OperandList.
Reviewed by Duncan Exon Smith.
llvm-svn: 239620
The raw non-instruction/constant form of this is still relying on being
able to access the pointee type from a pointer type - those will be
cleaned up later. For now, just focus on the cases where the pointee
type is easily accessible.
llvm-svn: 237958
Clang regressions were caused by more stringent assertion checking
introduced by this change. Small fix needed to clang has been committed
in r236751.
llvm-svn: 236752
Require the pointee type to be passed explicitly and assert that it is
correct. For now it's possible to pass nullptr here (and I've done so in
a few places in this patch) but eventually that will be disallowed once
all clients have been updated or removed. It'll be a long road to get
all the way there... but if you have the cahnce to update your callers
to pass the type explicitly without depending on a pointer's element
type, that would be a good thing to do soon and a necessary thing to do
eventually.
llvm-svn: 233938
This pushes the use of PointerType::getElementType up into several
callers - I'll essentially just have to keep pushing that up the stack
until I can eliminate every call to it...
llvm-svn: 233604
I'm just going to migrate these in a pretty ad-hoc & incremental way -
providing the backwards compatible API for now, then locally removing
it, fixing a few callers, adding it back in and commiting those callers.
Rinse, repeat.
The assertions should ensure that if I get this wrong we'll find out
about it and not just have one giant patch to revert, recommit, revert,
recommit, etc.
llvm-svn: 232240
We didn't properly handle the out-of-bounds case for
ConstantAggregateZero and UndefValue. This would manifest as a crash
when the constant folder was asked to fold a load of a constant global
whose struct type has no operands.
This fixes PR22595.
llvm-svn: 229352
Required some APInt massaging to get proper empty/tombstone values. Apart
from making the code a bit simpler this also reduces the bucket size of
the ConstantInt map from 32 to 24 bytes.
llvm-svn: 223478
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.
This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...
llvm-svn: 222334
Having two ways to do this doesn't seem terribly helpful and
consistently using the insert version (which we already has) seems like
it'll make the code easier to understand to anyone working with standard
data structures. (I also updated many references to the Entry's
key and value to use first() and second instead of getKey{Data,Length,}
and get/setValue - for similar consistency)
Also removes the GetOrCreateValue functions so there's less surface area
to StringMap to fix/improve/change/accommodate move semantics, etc.
llvm-svn: 222319
Windows defines NULL to 0, which when used as an argument to a variadic
function, is not a null pointer constant. As a result, Clang's
-Wsentinel fires on this code. Using '0' would be wrong on most 64-bit
platforms, but both MSVC and Clang make it work on Windows. Sidestep the
issue with nullptr.
llvm-svn: 221940
Change `ConstantExpr` to follow the model the other constants are using:
only malloc a replacement if it's going to be used. This fixes a subtle
bug where if an API user had used `ConstantExpr::get()` already to
create the replacement but hadn't given it any users, we'd delete the
replacement.
This relies on r216015 to thread `OnlyIfReduced` through
`ConstantExpr::getWithOperands()`.
llvm-svn: 216016
In order to change `ConstantExpr::replaceUsesOfWithOnConstant()` to work
like other constants (e.g., using `ConstantArray::getImpl()`), thread
`OnlyIfReduced` through as necessary. When `OnlyIfReduced` is false,
there's no functionality change. When it's true, if there's no constant
folding or type changes `nullptr` is returned instead of the new
constant.
`ConstantExpr::replaceUsesOfWithOnConstant()` will be updated to use the
"true" version in a follow-up commit.
llvm-svn: 216015
This reverts commit r215981, which reverted the above commits because
MSVC std::equal asserts on nullptr iterators, and thes commits
introduced an `ArrayRef::equals()` on empty ArrayRefs.
ArrayRef was changed not to use std::equal in r215986.
llvm-svn: 215987
Avoid creating a new `ConstantVector` on an RAUW of one of its members.
This reduces RAUW traffic on any containing constant.
This is part of PR20515.
llvm-svn: 215966
Previously, `ConstantArray::replaceUsesOfWithOnConstant()` neglected to
check whether it becomes a `ConstantDataArray`. Call
`ConstantArray::getImpl()` to check for that.
llvm-svn: 215965
Introduce `getImpl()` that tries the simplification logic from `get()`
and then gives up. This allows the logic to be reused elsewhere in a
follow-up commit.
llvm-svn: 215963
Avoid RAUW-ing `ConstantExpr` when an operand changes unless the new
`ConstantExpr` already has users. This prevents the RAUW from rippling
up the expression tree unnecessarily.
This commit indirectly adds test coverage for r215953 (this is how I
came across the bug).
This is part of PR20515.
llvm-svn: 215960
Rewrite `ConstantUniqueMap` to be more similar to
`ConstantAggrUniqueMap`.
- Use a `DenseMap` with custom MapInfo instead of a `std::map` with
linear lookups and deletion.
- Don't waste memory explicitly storing (heavyweight) keys.
Only `ConstantExpr` and `InlineAsm` actually use this data structure, so
I also updated them to use it.
This code cleanup is a precursor to reducing RAUW traffic on
`ConstantExpr` -- I felt badly adding a new (linear) call to
`ConstantUniqueMap::FindExistingKey`, so this designs away the concern.
A follow-up commit will transition the users of `ConstantAggrUniqueMap`
over.
llvm-svn: 215957
While *most* (X sdiv 1) operations will get caught by InstSimplify, it
is still possible for a sdiv to appear in the worklist which hasn't been
simplified yet.
This means that it is possible for 0 - (X sdiv 1) to get transformed
into (X sdiv -1); dividing by -1 can make the transform produce undef
values instead of the proper result.
Sorry for the lack of testcase, it's a bit problematic because it relies
on the exact order of operations in the worklist.
llvm-svn: 215818
We would previously put dllimport variables in switch lookup tables, which
doesn't work because the address cannot be used in a constant initializer.
This is basically the same problem that we have in PR19955.
Putting TLS variables in switch tables also desn't work, because the
address of such a variable is not constant.
Differential Revision: http://reviews.llvm.org/D4220
llvm-svn: 211331
As a follow-up to r210375 which canonicalizes addrspacecast
instructions, this patch canonicalizes addrspacecast constant
expressions.
Given clang uses ConstantExpr::getAddrSpaceCast to emit addrspacecast
cosntant expressions, this patch is also a step towards having the
frontend emit canonicalized addrspacecasts.
Piggyback a minor refactor in InstCombineCasts.cpp
Update three affected tests in addrspacecast-alias.ll,
access-non-generic.ll and constant-fold-gep.ll and added one new test in
constant-fold-address-space-pointer.ll
llvm-svn: 211004
Given the following C code llvm currently generates suboptimal code for
x86-64:
__m128 bss4( const __m128 *ptr, size_t i, size_t j )
{
float f = ptr[i][j];
return (__m128) { f, f, f, f };
}
=================================================
define <4 x float> @_Z4bss4PKDv4_fmm(<4 x float>* nocapture readonly %ptr, i64 %i, i64 %j) #0 {
%a1 = getelementptr inbounds <4 x float>* %ptr, i64 %i
%a2 = load <4 x float>* %a1, align 16, !tbaa !1
%a3 = trunc i64 %j to i32
%a4 = extractelement <4 x float> %a2, i32 %a3
%a5 = insertelement <4 x float> undef, float %a4, i32 0
%a6 = insertelement <4 x float> %a5, float %a4, i32 1
%a7 = insertelement <4 x float> %a6, float %a4, i32 2
%a8 = insertelement <4 x float> %a7, float %a4, i32 3
ret <4 x float> %a8
}
=================================================
shlq $4, %rsi
addq %rdi, %rsi
movslq %edx, %rax
vbroadcastss (%rsi,%rax,4), %xmm0
retq
=================================================
The movslq is uneeded, but is present because of the trunc to i32 and then
sext back to i64 that the backend adds for vbroadcastss.
We can't remove it because it changes the meaning. The IR that clang
generates is already suboptimal. What clang really should emit is:
%a4 = extractelement <4 x float> %a2, i64 %j
This patch makes that legal. A separate patch will teach clang to do it.
Differential Revision: http://reviews.llvm.org/D3519
llvm-svn: 207801
This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
detail
2) Change it to actually be a *Use* iterator rather than a *User*
iterator.
3) Add an adaptor which is a User iterator that always looks through the
Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
they wanted a use_iterator (and to explicitly dig out the User when
needed), or a user_iterator which makes the Use itself totally
opaque.
Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.
The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.
However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]
llvm-svn: 203364
name might indicate, it is an iterator over the types in an instruction
in the IR.... You see where this is going.
Another step of modularizing the support library.
llvm-svn: 202815
one, but not create one. This is useful in the verifier when we want to
query the constant if it exists but not create one. To be used in an
upcoming commit.
llvm-svn: 199568
A non-constant-foldable static initializer expression containing insertvalue or
extractvalue had been causing an assert:
Constants.cpp:1971: Assertion `FC && "ExtractValue constant expr couldn't be
folded!"' failed.
Now we report a more-sensible "Unsupported expression in static initializer"
error instead.
Fixes PR15417.
llvm-svn: 186044
This pass was assuming that if hasAddressTaken() returns false for a
function, the function's only uses are call sites. That's not true
because there can be references by BlockAddresses too.
Fix the pass to handle this case. Fix
BlockAddress::replaceUsesOfWithOnConstant() to allow a function's type
to be changed by RAUW'ing the function with a bitcast of the recreated
function.
Patch by Mark Seaborn.
llvm-svn: 183933
This is basically the same fix in three different places. We use a set to avoid
walking the whole tree of a big ConstantExprs multiple times.
For example: (select cmp, (add big_expr 1), (add big_expr 2))
We don't want to visit big_expr twice here, it may consist of thousands of
nodes.
The testcase exercises this by creating an insanely large ConstantExprs out of
a loop. It's questionable if the optimizer should ever create those, but this
can be triggered with real C code. Fixes PR15714.
llvm-svn: 179458
we weren't differntiating floating-point zeroinitializers from other zero-initializers)
which was causing problems for code relying upon a + (+0.0f) to, eg, flush denormals to
0. Make the scalar and vector cases have the same behaviour.
llvm-svn: 177279
Previously we tried to infer it from the bit width size, with an added
IsIEEE argument for the PPC/IEEE 128-bit case, which had a default
value. This default value allowed bugs to creep in, where it was
inappropriate.
llvm-svn: 173138
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.
There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.
The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.
I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).
I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.
llvm-svn: 171366
Aside from moving the actual files, this patch only updates the build
system and the source file comments under lib/... that are relevant.
I'll be updating other docs and other files in smaller subsequnet
commits.
While I've tried to test this, but it is entirely possible that there
will still be some build system fallout.
Also, note that I've not changed the library name itself: libLLVMCore.a
is still the library name. I'd be interested in others' opinions about
whether we should rename this as well (I think we should, just not sure
what it might break)
llvm-svn: 171359
Owen Anderson