This is a patch to improve StringTableBuilder's performance. That class'
finalize function is very hot particularly in LLD because the function
does tail-merge strings in string tables or SHF_MERGE sections.
Generic std::sort-style sorter is not efficient for sorting strings.
The function implemented in this patch seems to be more efficient.
Here's a benchmark of LLD to link Clang with or without this patch.
The numbers are medians of 50 runs.
-O0
real 0m0.455s
real 0m0.430s (5.5% faster)
-O3
real 0m0.487s
real 0m0.452s (7.2% faster)
Since that is a benchmark of the whole linker, the speedup of
StringTableBuilder itself is much more than that.
http://reviews.llvm.org/D14053
llvm-svn: 251337
We should remove noalias along with dereference and dereference_or_null attributes
because statepoint could potentially touch the entire heap including noalias objects.
Differential Revision: http://reviews.llvm.org/D14032
llvm-svn: 251333
This adds a couple of optimization remarks to the SamplePGO
transformation. When it decides to inline a hot function (to mimic the
inline stack and repeat useful inline decisions in the original build).
It will also report branch destinations. For instance, given the code
fragment:
6 if (i < 1000)
7 sum -= i;
8 else
9 sum += -i * rand();
If the 'else' branch is taken most of the time, building this code with
-Rpass=sample-profile will produce:
a.cc:9:14: remark: most popular destination for conditional branches at small.cc:6:9 [-Rpass=sample-profile]
sum += -i * rand();
^
llvm-svn: 251330
Processing bitcode from a different LLVM version can lead to
unexpected behavior. The LLVM project guarantees autoupdating
bitcode from a previous minor revision for the same major, but
can't make any promise when reading bitcode generated from a
either a non-released LLVM, a vendor toolchain, or a "future"
LLVM release. This patch aims at being more user-friendly and
allows a bitcode produce to emit an optional block at the
beginning of the bitcode that will contains an opaque string
intended to describe the bitcode producer information. The
bitcode reader will dump this information alongside any error it
reports.
The optional block also includes an "epoch" number, monotonically
increasing when incompatible changes are made to the bitcode. The
reader will reject bitcode whose epoch is different from the one
expected.
Differential Revision: http://reviews.llvm.org/D13666
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 251325
Android libc provides a fixed TLS slot for the unsafe stack pointer,
and this change implements direct access to that slot on AArch64 via
__builtin_thread_pointer() + offset.
This change also moves more code into TargetLowering and its
target-specific subclasses to get rid of target-specific codegen
in SafeStackPass.
This change does not touch the ARM backend because ARM lowers
builting_thread_pointer as aeabi_read_tp, which is not available
on Android.
The previous iteration of this change was reverted in r250461. This
version leaves the generic, compiler-rt based implementation in
SafeStack.cpp instead of moving it to TargetLoweringBase in order to
allow testing without a TargetMachine.
llvm-svn: 251324
We were previously overflowing a 32-bit multiply operation when emitting large
(>512MB) bitcode files, resulting in corrupted bitcode. Fix by extending
one of the operands to 64 bits.
There are a few other 32-bit integer types in this code that seem like they
also ought to be extended to 64 bits; this will be done separately.
llvm-svn: 251323
In PIC mode we were previously computing global variable addresses (or GOT
entry addresses) by adding the PC, the PC-relative GOT displacement and
the GOT-relative symbol/GOT entry displacement. Because the latter two
displacements are fixed, we ended up performing one more addition than
necessary.
This change causes us to compute addresses using a single PC-relative
displacement, resulting in a shorter code sequence. This reduces code size
by about 4% in a recent build of Chromium for Android.
As a result of this change we no longer need to compute the GOT base address
in the ARM backend, which allows us to remove the Global Base Reg pass and
SDAG lowering for the GOT.
We also now no longer use the GOT when addressing a symbol which is known
to be defined in the same linkage unit. Specifically, the symbol must have
either hidden visibility or a strong definition in the current module in
order to not use the the GOT.
This is a change from the previous behaviour where we would use the GOT to
address externally visible symbols defined in the same module. I think the
only cases where this could matter are cases involving symbol interposition,
but we don't really support that well anyway.
Differential Revision: http://reviews.llvm.org/D13650
llvm-svn: 251322
This issue is triggered in PGO mode when bootstrapping LLVM. It seems that it is not guaranteed that edge weights are always greater than zero which are read from profile data.
llvm-svn: 251317
Instead of XFAIL-ing the tests with the wrong usage of the "interrupt"
attribute, we should check that we emit the correct error messages to
the user.
llvm-svn: 251295
Even though we may not know the value of the shifter operand, it's possible we know the shifter operand is non-zero. This can allow us to infer more known bits - for example:
%1 = load %p !range {1, 5}
%2 = shl %q, %1
We don't know %1, but we do know that it is nonzero so %2[0] is known zero, and importantly %2 is known non-zero.
Calling isKnownNonZero is nontrivially expensive so use an Optional to run it lazily and cache its result.
llvm-svn: 251294
Summary:
Replace (const SCEVAddRecExpr *) with cast<SCEVAddRecExpr>.
Rename SCEVApplyRewriter to SCEVLoopAddRecRewriter (which is a more
appropriate name) since the description is "takes a scalar evolution
expression and applies the Map (Loop -> SCEV) to all AddRecExprs."
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D14065
llvm-svn: 251292
Vectorization of memory instruction (Load/Store) is possible when the pointer is coming from GEP. The GEP analysis allows to estimate the profit.
In some cases we have a "bitcast" between GEP and memory instruction.
I added code that skips the "bitcast".
http://reviews.llvm.org/D13886
llvm-svn: 251291
Summary:
This patch adds support for using the "interrupt" attribute on Mips
for interrupt handling functions. At this time only mips32r2+ with the
o32 ABI with the static relocation model is supported. Unsupported
configurations will be rejected
Patch by Simon Dardis (+ clang-format & some trivial changes to follow the
LLVM coding standards by me).
Reviewers: mpf, dsanders
Subscribers: dsanders, vkalintiris, llvm-commits
Differential Revision: http://reviews.llvm.org/D10768
llvm-svn: 251286
Summary:
Add a SCEVRewriteVisitor class which contains the common
visiting patterns used when rewriting SCEVs.
SCEVParameterRewriter and SCEVApplyRewriter now inherit
from SCEVRewriteVisitor (and are therefore much simpler).
Reviewers: anemet, mzolotukhin, sanjoy
Subscribers: rengolin, llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D13242
llvm-svn: 251283
Summary:
InstCombine tries to transform GEP(PHI(GEP1, GEP2, ..)) into GEP(GEP(PHI(...))
when possible. However, this may leave the old PHI node around. Even if we
do end up folding the GEPs, having an extra PHI node might not be beneficial.
This change makes the transformation more conservative. We now only do this if
the PHI has only one use, and can therefore be removed after the transformation.
Reviewers: jmolloy, majnemer
Subscribers: mcrosier, mssimpso, llvm-commits
Differential Revision: http://reviews.llvm.org/D13887
llvm-svn: 251281
the module pointer type passed in by the user.
The previous ownership scheme, where the user pointer was always moved into a
std::shared_ptr, breaks if the user passes in a raw pointer.
Discovered while working on the Orc C API, which should be landing shortly.
I expect to include a test-case with that.
llvm-svn: 251273
GNU as and Darwin give the various binary operators different
precedence. LLVM's MC supported the Darwin semantics but not the GNU
semantics.
This fixes PR25311.
llvm-svn: 251271
We didn't validate that the .word directive was given a sane value,
leading to crashes when we attempt to write out the object file.
Instead, perform some validation and issue a diagnostic pointing at the
start of the diagnostic.
llvm-svn: 251270
Instead of playing around with dominance to verify if the possible expansion of
a scop region is indeed a single entry single exit region, we now distinguish
two cases. In case we only append a basic block, all edges entering this basic
block need to have come from within the region that is expanded. In case we join
two regions, the source basic blocks of the edges that end at the entry node of
the region that is appended most be part of either the original region or the
region that is appended.
This change will be tested through Polly.
This fixes llvm.org/PR25242
llvm-svn: 251267
Windows has two different mangling specifiers. `x` is used on x86 for the `_`
UserLabelPrefix. Others use `w` for the no UserLabelPrefix.
llvm-svn: 251260
When the target does not support these intrinsics they should be converted to a chain of scalar load or store operations.
If the mask is not constant, the scalarizer will build a chain of conditional basic blocks.
I added isLegalMaskedGather() isLegalMaskedScatter() APIs.
Differential Revision: http://reviews.llvm.org/D13722
llvm-svn: 251237
