BDCE is a bit-tracking dead code elimination pass. It is based on ADCE (the
"aggressive DCE" pass), with the added capability to track dead bits of integer
valued instructions and remove those instructions when all of the bits are
dead.
Currently, it does not actually do this all-bits-dead removal, but rather
replaces the instruction's uses with a constant zero, and lets instcombine (and
the later run of ADCE) do the rest. Because we essentially get a run of ADCE
"for free" while tracking the dead bits, we also do what ADCE does and removes
actually-dead instructions as well (this includes instructions newly trivially
dead because all bits were dead, but not all such instructions can be removed).
The motivation for this is a case like:
int __attribute__((const)) foo(int i);
int bar(int x) {
x |= (4 & foo(5));
x |= (8 & foo(3));
x |= (16 & foo(2));
x |= (32 & foo(1));
x |= (64 & foo(0));
x |= (128& foo(4));
return x >> 4;
}
As it turns out, if you order the bit-field insertions so that all of the dead
ones come last, then instcombine will remove them. However, if you pick some
other order (such as the one above), the fact that some of the calls to foo()
are useless is not locally obvious, and we don't remove them (without this
pass).
I did a quick compile-time overhead check using sqlite from the test suite
(Release+Asserts). BDCE took ~0.4% of the compilation time (making it about
twice as expensive as ADCE).
I've not looked at why yet, but we eliminate instructions due to having
all-dead bits in:
External/SPEC/CFP2006/447.dealII/447.dealII
External/SPEC/CINT2006/400.perlbench/400.perlbench
External/SPEC/CINT2006/403.gcc/403.gcc
MultiSource/Applications/ClamAV/clamscan
MultiSource/Benchmarks/7zip/7zip-benchmark
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229462 91177308-0d34-0410-b5e6-96231b3b80d8
This patch replaces most of the Orc indirection utils API with a new class:
JITCompileCallbackManager, which creates and manages JIT callbacks.
Exposing this functionality directly allows the user to create callbacks that
are associated with user supplied compilation actions. For example, you can
create a callback to lazyily IR-gen something from an AST. (A kaleidoscope
example demonstrating this will be committed shortly).
This patch also refactors the CompileOnDemand layer to use the
JITCompileCallbackManager API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229461 91177308-0d34-0410-b5e6-96231b3b80d8
While looking at a heap profile of a clang LTO bootstrap with -g, I
noticed that 2.2% of memory in an `llvm-lto` of clang is from calling
`DebugLoc::get()` in `collectVariableInfo()` (accounting for ~40% of
memory used for `MDLocation`s).
I suspect this was introduced by r226736, whose goal was to prevent
uniquing of `DebugLoc`s (goal achieved, if so).
There's no reason we need a `DebugLoc` here at all -- it was just being
used for (in)convenient API -- so the fix is to pass the scope and
inlined-at directly to `LexicalScopes::findInlinedScope()`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229459 91177308-0d34-0410-b5e6-96231b3b80d8
This required some minor API to be added to these types to avoid
needing temp files.
Also, I've used initializer lists in the tests, as MSVC 2013 claims to
support them. I'll redo this without them if the bots complain.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229455 91177308-0d34-0410-b5e6-96231b3b80d8
and LazyEmittingLayer of Orc.
This method allows you to immediately emit and finalize a module. It is required
by an upcoming refactor of the indirection utils and the compile-on-demand
layer.
I've filed http://llvm.org/PR22608 to write unit tests for this and other Orc
APIs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229451 91177308-0d34-0410-b5e6-96231b3b80d8
The other InstrProfReader::create factories were updated to return
ErrorOr in r221120, and it's odd for these APIs not to match.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229433 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a safe interface to the machine independent InputArg struct
for accessing the index of the original (IR-level) argument. When a
non-native return type is lowered, we generate the hidden
machine-level sret argument on-the-fly. Before this fix, we were
representing this argument as OrigArgIndex == 0, which is an outright
lie. In particular this crashed in the AArch64 backend where we
actually try to access the type of the original argument.
Now we use a sentinel value for machine arguments that have no
original argument index. AArch64, ARM, Mips, and PPC now check for this
case before accessing the original argument.
Fixes <rdar://19792160> Null pointer assertion in AArch64TargetLowering
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229413 91177308-0d34-0410-b5e6-96231b3b80d8
Remember if the node ever was in this state instead of checking just the
final state.
Reviewed by Arnaud de Grandmaison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229400 91177308-0d34-0410-b5e6-96231b3b80d8
classes. We can't use template aliases because on MSVC they don't appear
to work correctly in the common usage such as Format.h.
Many thanks to Zach for doing all the testing and debugging here. I just
slotted the fix into the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229362 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229352 91177308-0d34-0410-b5e6-96231b3b80d8
Introduces a subset of C++14 integer sequences in STLExtras. This is
just enough to support unpacking a std::tuple into the arguments of
snprintf, we can add more of it when it's actually needed.
Also removes an ancient macro hack that leaks a macro into the global
namespace. Clean up users that made use of the convenient hack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229337 91177308-0d34-0410-b5e6-96231b3b80d8
The "dereferenceable" attribute cannot be added via .addAttribute(),
since it also expects a size in bytes. AttrBuilder#addAttribute or
AttributeSet#addAttribute is wrapped by classes Function, InvokeInst,
and CallInst. Add corresponding wrappers to
AttrBuilder#addDereferenceableAttr.
Having done this, propagate the dereferenceable attribute via
gc.relocate, adding a test to exercise it. Note that -datalayout is
required during execution over and above -instcombine, because
InstCombine only optionally requires DataLayoutPass.
Differential Revision: http://reviews.llvm.org/D7510
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229265 91177308-0d34-0410-b5e6-96231b3b80d8
Dumping the global scope contains a lot of very uninteresting
things and is generally polluted with a lot of random junk.
Furthermore, it dumps values unsorted, making it hard to read.
This patch dumps known interesting types only, and as a side
effect sorts the list by symbol type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229232 91177308-0d34-0410-b5e6-96231b3b80d8
Canonicalize access to function attributes to use the simpler API.
getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
=> getFnAttribute(Kind)
getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
=> hasFnAttribute(Kind)
Also, add `Function::getFnStackAlignment()`, and canonicalize:
getAttributes().getStackAlignment(AttributeSet::FunctionIndex)
=> getFnStackAlignment()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229208 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r228939.
The commit broke something in the output of exception handling tables on
darwin x86-64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229203 91177308-0d34-0410-b5e6-96231b3b80d8
To be used in dsymutil (or any other client that wants to take
advantage of the fact that DIEs are stored in a vector).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229179 91177308-0d34-0410-b5e6-96231b3b80d8
Original commit message:
SmallVector: Resolve a long-standing fixme by using the existing unitialized_copy dispatch.
This makes append() use memcpy for trivially copyable types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229149 91177308-0d34-0410-b5e6-96231b3b80d8
This correctly prints the function pointers, and also prints
function signatures for symbols as opposed to just types. So
actual functions in your program will now be printed with full
name and signature, as opposed to just name as before.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229129 91177308-0d34-0410-b5e6-96231b3b80d8
Although such nodes are allocatable, the cost of spilling may be less than
allocating to register, so spilling the node may provide a better solution.
The assert does not account for this case, so remove it for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229103 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.
This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.
The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229094 91177308-0d34-0410-b5e6-96231b3b80d8
regressions for LLDB on Linux. Rafael indicated on lldb-dev that we
should just go ahead and revert these but that he wasn't at a computer.
The patches backed out are as follows:
r228980: Add support for having multiple sections with the name and ...
r228889: Invert the section relocation map.
r228888: Use the existing SymbolTableIndex intsead of doing a lookup.
r228886: Create the Section -> Rel Section map when it is first needed.
These patches look pretty nice to me, so hoping its not too hard to get
them re-instated. =D
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229080 91177308-0d34-0410-b5e6-96231b3b80d8
In particular this patch adds the ability to dump complete
function signature information including argument types as
correctly formatted strings. A side effect of this is that
almost all symbol and meta types are now formatted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229076 91177308-0d34-0410-b5e6-96231b3b80d8
No caller specifies anything different; these parameters are dead code
and probably always have been. The new hierarchy doesn't bother with
the fields at all (see r228607 and r228652).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229037 91177308-0d34-0410-b5e6-96231b3b80d8
