part of getting started with LLVM.
The LLVM getting started document is in woeful need of attention. I may
get to some of this, but some random notes for folks interested:
1) We need to separate the getting started steps for folks who are
interested in the core LLVM libs and nothing else, folks interested
in a nifty C++ toolchain and nothing else, and folks interested in
both.
2) We should include documentation for both release archives, svn, and
git in equal portion, and we should document all of the various
repositories of interest: llvm, clang, clang-tools-extra,
compiler-rt, lld, libcxx, test-suite.
3) We should document the CMake build. We should probably document the
CMake build first, and give a fall-back set of docs for the Makefile
build for the use cases where that is still the preferred solution.
This would more closely match the use cases that folks in the open
source community are likely to have, and would remove a point of
discrepancy between Linux, Windows, and Mac instructions.
4) Probably a ton of other modernization stuff that I've not thought of
here.
Anyways, if anyone at all is interested, please help clean up this
document. It is much needed.
llvm-svn: 189732
implementation files. While doc generation systems don't need this,
humans do benefit from it. Not everyone reads all code through doxygen.
llvm-svn: 189704
This function attribute indicates that the function is not optimized
by any optimization or code generator passes with the
exception of interprocedural optimization passes.
llvm-svn: 189101
This adds a llvm.copysign intrinsic; We already have Libfunc recognition for
copysign (which is turned into the FCOPYSIGN SDAG node). In order to
autovectorize calls to copysign in the loop vectorizer, we need a corresponding
intrinsic as well.
In addition to the expected changes to the language reference, the loop
vectorizer, BasicTTI, and the SDAG builder (the intrinsic is transformed into
an FCOPYSIGN node, just like the function call), this also adds FCOPYSIGN to a
few lists in LegalizeVector{Ops,Types} so that vector copysigns can be
expanded.
In TargetLoweringBase::initActions, I've made the default action for FCOPYSIGN
be Expand for vector types. This seems correct for all in-tree targets, and I
think is the right thing to do because, previously, there was no way to generate
vector-values FCOPYSIGN nodes (and most targets don't specify an action for
vector-typed FCOPYSIGN).
llvm-svn: 188728
All libm floating-point rounding functions, except for round(), had their own
ISD nodes. Recent PowerPC cores have an instruction for round(), and so here I'm
adding ISD::FROUND so that round() can be custom lowered as well.
For the most part, this is straightforward. I've added an intrinsic
and a matching ISD node just like those for nearbyint() and friends. The
SelectionDAG pattern I've named frnd (because ISD::FP_ROUND has already claimed
fround).
This will be used by the PowerPC backend in a follow-up commit.
llvm-svn: 187926
This change makes test with RUN lines like
RUN: opt ... | FileCheck
fail if opt fails, even if it prints what FileCheck wants. Enabling this
found some interesting cases of broken tests that were not being noticed
because opt (or some other tool) was crashing late.
Pipefail is used when the shell supports it or when using the internal
python based tester.
llvm-svn: 187261
Back in r140220 we removed the autoconf code that would set LLVMCC_OPTION
since it was only used by the test-suite. This patch now removes code
that would only be used if LLVMCC_OPTION was set.
llvm-svn: 187154
CHECK-LABEL is meant to be used in place on CHECK on lines containing identifiers or other unique labels (they need not actually be labels in the source or output language, though.) This is used to break up the input stream into separate blocks delineated by CHECK-LABEL lines, each of which is checked independently. This greatly improves the accuracy of errors and fix-it hints in many cases, and allows for FileCheck to recover from errors in one block by continuing to subsequent blocks.
Some tests will be converted to use this new directive in forthcoming patches.
llvm-svn: 186162
"Writing an LLVM Compiler Backend" can be misinterpreted as meaning
"backend" in the sense of "using LLVM as a backend for your compiler for
your new language". This new name is less ambiguous.
As a bonus, this brings the title in line with the file name.
llvm-svn: 185377
The Builtin attribute is an attribute that can be placed on function call site that signal that even though a function is declared as being a builtin,
rdar://problem/13727199
llvm-svn: 185049
This patch modifies TableGen to generate a function in
${TARGET}GenInstrInfo.inc called getNamedOperandIdx(), which can be used
to look up indices for operands based on their names.
In order to activate this feature for an instruction, you must set the
UseNamedOperandTable bit.
For example, if you have an instruction like:
def ADD : TargetInstr <(outs GPR:$dst), (ins GPR:$src0, GPR:$src1)>;
You can look up the operand indices using the new function, like this:
Target::getNamedOperandIdx(Target::ADD, Target::OpName::dst) => 0
Target::getNamedOperandIdx(Target::ADD, Target::OpName::src0) => 1
Target::getNamedOperandIdx(Target::ADD, Target::OpName::src1) => 2
The operand names are case sensitive, so $dst and $DST are considered
different operands.
This change is useful for R600 which has instructions with a large number
of operands, many of which model single bit instruction configuration
values. These configuration bits are common across most instructions,
but may have a different operand index depending on the instruction type.
It is useful to have a convenient way to look up the operand indices,
so these bits can be generically set on any instruction.
llvm-svn: 184879
Archive files (.a) can have a symbol table indicating which object
files in them define which symbols. The purpose of this symbol table
is to speed up linking by allowing the linker the read only the .o
files it is actually going to use instead of having to parse every
object's symbol table.
LLVM's archive library currently supports a LLVM specific format for
such table. It is hard to see any value in that now that llvm-ld is
gone:
* System linkers don't use it: GNU ar uses the same plugin as the
linker to create archive files with a regular index. The OS X ar
creates no symbol table for IL files, I assume the linker just parses
all IL files.
* It doesn't interact well with archives having both IL and native objects.
* We probably don't want to be responsible for yet another archive
format variant.
This patch then:
* Removes support for creating and reading such index from lib/Archive.
* Remove llvm-ranlib, since there is nothing left for it to do.
We should in the future add support for regular indexes to llvm-ar for
both native and IL objects. When we do that, llvm-ranlib should be
reimplemented as a symlink to llvm-ar, as it is equivalent to "ar s".
llvm-svn: 184019
The effect of llvm.used is to introduce an invisible reference, so this seems
a reasonable restriction. It will be used to provide an easy ordering of
the entries in llvm.used.
llvm-svn: 183743
Several LLVM headers are moved. The code listings in
LLVM tutorial are not updated yet.
This CL removes the code replica in the .rst, and replace
them with a literalinclude directive, so that sphinx can
include the latest code automatically.
llvm-svn: 183607
This updates the debug info metadata schema documentation for various
schema changes made recently surrounding filename information for
scopes and the representation of imported entities.
llvm-svn: 182817
- llvm.loop.parallel metadata has been renamed to llvm.loop to be more generic
by making the root of additional loop metadata.
- Loop::isAnnotatedParallel now looks for llvm.loop and associated
llvm.mem.parallel_loop_access
- document llvm.loop and update llvm.mem.parallel_loop_access
- add support for llvm.vectorizer.width and llvm.vectorizer.unroll
- document llvm.vectorizer.* metadata
- add utility class LoopVectorizerHints for getting/setting loop metadata
- use llvm.vectorizer.width=1 to indicate already vectorized instead of
already_vectorized
- update existing tests that used llvm.loop.parallel and
llvm.vectorizer.already_vectorized
Reviewed by: Nadav Rotem
llvm-svn: 182802
Other than recognizing the attribute, the patch does little else.
It changes the branch probability analyzer so that edges into
blocks postdominated by a cold function are given low weight.
Added analysis and code generation tests. Added documentation for the
new attribute.
llvm-svn: 182638
This implements the @llvm.readcyclecounter intrinsic as the specific
MRC instruction specified in the ARM manuals for CPUs with the Power
Management extensions.
Older CPUs had slightly different methods which may also have to be
implemented eventually, but this should cover all v7 cases.
rdar://problem/13939186
llvm-svn: 182603
Chandler Carruth